Enhancing Power System Reliability

Chapter 1: Introduction

This chapter focus on background of the study that include the power reliability and availability, approaches taken to improve such as availability and reliability, and design of the modern power systems and networks. Importantly, it captures the mechanism adopted within various power networks to enhance power quality, reliability, and availability to the end users. Additionally, it outlines the basic of IEC 61850 and its application in power transmission system in recent years coupled with background information on the IEC 61850 in modern power networks. It also present the problems, aim, and objective of this research project works a thesis outline.

1.1 Background of the study

Over the past decade, demand of power reliability and availability coupled with efficiency and cheaper sources have dominated the energy sector that includes generation, transmission, and distribution. According to Nair et al. (2009) and Bouhafs et al. (2011), advancement of technology that heavily depend on electrical power such as in the hospitals, nuclear power plants, data centres, communication centres, and base stations have forced power generating, transmitting, and distributing companies to seeking of ways ensuring availability and reliability. This increasing demand for power by manufacturing sector, computers power, and constant supply in critical facilities such as nuclear power plants and hospitals, push mean load density and consumption to critical thresholds (Niyato et al., 2011; Amjady, and Daraeepour, 2010). As such, unplanned interruptions due power outages and system failures may results in heavy losses, failure of critical services, loss of lives, safety, and economic viability and production process. In power systems and networks, the biggest challenge is meeting expanding demand while ensuring efficiency, availability, and reliability are maintained. Importance of power availability, quality, and reliability particularly to the critical power environments has led to emphasis and demand innovation and adoption of new approaches to mitigate the issues. Such technologies as smart grids, use of artificial intelligence, and adoption of communication protocols are common technologies collectively driven by attempt to improve power maintainability, manageability, reliability, and quality. Recently, in attempt to close the gap of the challenge, energy intelligence has been incorporated into power networks and systems without compromising on its supply stability. Zhang et al. (2010) indicates that such intelligent systems captures and reports current system status, performance indicators, load forecasting, and provides data analytics. Some technologies such as PowerLogic software allow tracking of real-time power information to enhance efficiency and maintain reliability (Hu et al., 2011). Fundamentally to this new invention in the industry is incorporate planning, monitoring, analysis, and implementation of approaches guided by eliminating unplanned interruption and improving power availability and reliability. (RFE) described power availability as the mean time taken per year when the power is present at the load terminals. On the other hand, power reliability can be taken as a probability of the system and services providers to provide quality and reliable power over a given period. Studies indicate poor maintenance practices are the leading cause of low reliability and availability of power at load end (Besnard et al., 2010; Yssaad et al., 2014). Fischer et al. (2014) indicated that availability could be improved through implementing factors geared towards improving maximizing uptime (reliability) while reducing downtime high maintainability of a system. Prominently, artificial intelligence and automation have become very common in maintenance of power networks and systems that include power lines and substations.

In 1995, International Electrotechnical Commission (IEC), a 60 member group, created a IEC61850 standard aimed at standardizing protocols to deal with different data in a substations, and promote higher inter-operability between power networks and different players in the field. Additionally, the protocols define basic services shared by different substations and whole network, shared data storage system, and common testing procedure as defined by set guideline. According to Kaneda et al. (2008), ccommunication in IEC61850-based substation automation allows for a new type of solution that delivers efficient performance. This efficiency is introduced by exchanging information in real-time, reducing the cost of the lifecycle and the interoperability identified as the main drivers for its use. In recent years, the growing demand in the typical IEC61850 reason there next to increased numbers of research papers and practical projects. Georgilakis and Hatziargyriou (2015) argued that the future of substations would face a more robust demand because of new laws, taxes, and deregulations. For example, Sweden, issue a new law that does not allow interruptions of more than 24 hours after 2011 (Forouzan, 2007). Essentially, engineers in the substations have many opportunities to develop fail-safe mechanism reliability by enabling relays to exchange messages in bus protection, breaker failure or many other protection schemes. Direct relay connection allows the different protection schemes to be significantly reduced overall cost. Around the same time, they reduce overall protection operating time for any liability within the protection region (Apostolov, 2013).

1.2 Synchronization level required for IEC 61850 by application is SAS

In a substation consisting of many other distributed Intelligent Electronic Devices (IEDs) such as control devices, sensors and actuators linked by a power infrastructure can be regarded as a traditional connected control system. Through designing and support of innovative all-digital protection, the incorporation of peer-to-peer IEC 61850-9-2 sampled values (SVs) and IEC 61850-8-1 GOOSE with other IEDs enabling information-exchange have enhanced systems and network protections. According to Ali et al. (2015), reliability in transmission include instantaneous performance of the Generic Object-Oriented Substation Event (GOOSE) and SVs data and information over a network play a core role in determining protection of IEC 61850 Substation Automation Systems (SAS). The applications for security, automation, and control that can be introduced in SAS have an efficiency that depends exclusively on the precision of the distributed systems for synchronization. Different architecture such as substation communication network (SCN) currently exist designed to address the need of reliability, availability, and deterministic performance (Ali et al., 2015). Some applicants can benefit from precise synchronizing, while others cannot solely be performed without cautious time reference allocation: Differential privileges that measure current can be introduced within the affected stations, but the sensors must be synchronized with 100μs (De Dominicis, 2011).

The failure of the power network is determined by measuring the time required to reach the halfway point by the travelling wave; a synchro precision below 1μs is needed to determine the situation with adequate accuracy certainly. Martin (2014) pointed out that the standard IEEE C37.118 for measuring the synchrophasor defines the total vector error (TVE) that is the total difference between the real and measured phasors. The measurement equipment has to guarantee a TVE lower than 1% to satisfy the standard requirements, which means a synchronization accuracy on the order of 1μs.

1.3 Research problem

The IEC 61850 technology drawn up by Technical Commission Working Group 10 57 has had a profound influence on interconnectivity and data sharing between different power substation and related networks. However, critical issues related to smart grid technologies mainly about challenges and opportunities related to information and communication technology (ICT) and complexity of the distributions and substation of electrical power networks. Currently, due to industries demand reliability and availability of power with little leeway of unplanned interruption connection through sharing of data and information among different substations and networks, communication protocols outline standardised structures, guidelines, and storage systems have become paramount. The design of IEC 61850 protocols are intended to reduce bandwidth-free data management. Fast travel communication schemes using IEC 61850 results in high delay, network flooding, and reduced network security. The research offers spreading features of extra high-speed busbar communication travelling wave following the IEC 61850 technology. In this research, different connection methods are compared in simulation and compare their results with verified sources to get better connection method. It may be possible to reduce failure rates through measures such as the use of higher-strength materials, increasing the quality components, moderating extreme environmental conditions, or shortened maintenance, inspection, or overhaul intervals. Design analyses may include mechanical stress, corrosion, and radiation analyses for mechanical components, thermal analyses for mechanical and electrical components, and Electromagnetic Interference (EMI) analyses or measurements for electrical components and subsystems.

1.4 Research aim

The aim of the study is to analysis the power availability and reliability in modern power networks using IEC 61850 protocol. This paper is projected to provide a better considerate of the smart grid's technologies, potential benefits, and research challenges, and to generate interest among the research community in further exploring this promising area of research.

1.5 Research objective

This project is guided by the following objectives:

To critically review network topology, standards, and protocols implemented in the power system and network and smart grid technologies

To evaluate IEC 61850 communication protocol as applied to power reliability and availability in modern power system and network

To investigate the difficulties and benefits of each technique based on the simulation results using Optimized Network Engineering Tool (OPNET) software or Riverbed

To appraise the data collected from simulation and make recommendation on the implementation of IEC 61850 in power network aimed at enhancing reliability and availability of power.

1.6 Thesis outline

Chapter 1 is the introduction of this project planning and background of the use of IEC 61850 capturing the structures and interconnectivity of power networks and substation as well as their automation. It also the present research problem, justification, aim, and objective of this research project. The chapter 2 presents a literature review of topologies, interconnectivity, communication protocols, and current network technologies. Current usage of IEC 61850 in power system to improve availability and reliability. This chapter reviews the importance and applications of installed IEC 61850 systems. Relevant operating system example is also discussed in this chapter. In the third chapter, it captures methodology employed in data collection and thinking behind taking simulation as way of address the objectives and problems to the availability and reliability of the transmission system using IEC 61850. Riverbed software is used for system connection and results. Chapter 4 captures the simulation and sample results from previous verified researches. Furthermore, the chapter links the findings from simulation to the existing literature. Lastly, chapter 5 presents the overall summary of the research and the concluding remarks. It also includes further recommendations for improving system stability and topology connections for better results.

Literature review

2.1 Introduction

This chapter is a literature review of this research project aimed at critically reviewing existing texts on the power reliability, availability, power network communication protocols, and modern electrical power systems that include distribution, transmission lines, and substation. In addition, it evaluates the current usage of IEC 61850 in power system to improve availability and reliability. This chapter delve deep in the importance and applicability of installed IEC 61850 systems. Relevant operating system example is also discussed in this chapter. This review exhibited in this chapter is a part of the exploration as described in which proposes a standard based framework to differentiate covered in communication settings. Maintenance of a power network system is essential in ensuring reliability and availability, takes several forms that include preventive, reactive, preventive/condition-based, and reliability-centred maintenance. Also referred to as ‘run to failure’, Fischer et al. (2011) highlighted that reactive maintenance as a ignoring the system components or equipment until it fails in operation. According to Khosrojerdi et al. (2016), this approach works best in the non-critical scenarios. Preventive maintenance, on the other hand, is done on schedule. According to Phoothong et al. (2008), the idea is rooted on the concept that equipment or system failure is directly related to the usage and age. The biggest concerns with this approach is one cannot predict a failure rate of a system or equipment. Khosrojerdi et al. (2016) and Mijailovic (2008) argued that probability of a failure does not only necessarily correlate to the system age but also excess maintenance enhances chance of human error as well as shortening machine/system life.

2.2 IEC 61850 Standard

Since 1995, three groups of an International Electrotechnical Commission (IEC) project group comprised of approximately 60 members from different countries addressed all issues and aims and developed IEC 61850 standard. Developed in 2004 and update in 2011, IEC 61850 is a standard that enhance communication and automation in the power networks and substations. The protocol is a global norm for the definition of communications procedures in electrical substations for smart digital appliances and is a component of the IEC's 57 Electric power System Reference Architecture (Mackiewicz, 2006; Zhabelova, and Vyatkin, 2011). It allows devices from different substations and vendors to share data and information directly over the Ethernet connection. Similar to ordinary Local Area Network (LAN), the protocol is structured in a manner that it has separate section dealing with issues related to data, communications, and compliance working together to advance distributed automation and sharing of information. In a smart grids, this interconnectivity and automation is core to its rollout. According to Baoyi et al. (2013), a range of protocols is available for mapping the abstract information models described in IEC 61850 that include Manufacturing Message Specification (MMS), Generic Object-Oriented Substation Event (GOOSE), and Sampled Measured Values (SMV) are currently used in conventional mappings. The Technical Committee 57 (TC57) belongs to the International Electro-technical Commission has discharged the IEC 61850 standard that authorises interoperability between SAS gadgets such as IEDs, and empowers deliberation of correspondence administrations (IEC TC 57) (Elgargouri et al., 2015; Youssef et al., 2016). As stated by Higgins et al. (2010), it gives correspondence administrations models to station level, process and bay level equipment, as shown in Fig. 2.

As a general rule, the substation should still be operational when there is a failure in the SAS. According to Kanabar and Sidhu (2009), IEC61850 does not require the use of a specific power station architecture or redundancy for primary substation functions. In planning to assess the consistent quality of station transport IEC 61850 correspondences (Network protection & automation guide, 2011), GOOSE is chosen as an informing administration for the test setup. As captured by IEC 61850, GOOSE is a control model that enables transfer of event data that include value and status of the entire substation network. The GOOSE messages received by broadcast or multicast services with multiple physical devices can be utilised for interlocking, unsettling influence recording cross-activating, breaker disappointment assurance stumbling, directional correlation transport insurance, and numerous other propelled applications, along these lines wiping out broad designing in gear straights thus decreasing the expense of actualising, progressed conveyed security and control plans (Zhang et al., 2009). In 2004, another typical correspondence pattern was presented in projects for substation computerisation system IEC 61850. The IEC 61850 Technical Committee 57 (IEC, Geneva) built up a gathering of makers (ABB, Alstom, Schneider, SEL, Siemens, Toshiba, and so on.) and electrical utilities (Electricité de France, Iberdrola, Hydro-Quebec, and so forth.) to improve hardware interoperability (Mekkanen et al., 2012).

2.3 Network architecture in IEC 61850 Substation

The network topology applies to the physical or logical layout of a network. As described by Donetti et al. (2005), it defines the placement and interconnection with each other of separate nodes. Alternatively, the network topology can describe how nodes convey info (Palmer, and Steffan, 2000). However, it is possible to consider both network and physical topologies as models below. In the study on the architecture of communication network in design of smart grids, Budka et al. (2010) observed the rise of the smart grids has to adoption peer-to-peer and smart communications as the new trend within and between power networks and substation. In implementation of communication network, number of topologies can be followed with the common one being bus, ring, star, and hybrid. The following diagrams outlines different topologies as adopted in IEC 61850 substation showing arrangement of different components.

Each bay has ES, PR IED, MU, CB&IED, CB components, and these bay components must work together in order to successfully perform communication functions under IEC 61850 SAS in its traditional architectures. Every switch is connected via one of its ports to the previous or next switch in the cascade. Therefore, all Ethernet switches are connected in series in RBD of the cascade architecture as shown in Figure 3. Because of the direct connection between IEDs, star architecture provides the least latency (Kanabar, and Sidhu, 2009; Georg et al., 2013). However, if a central switch fails, all bays are disconnected, thereby reducing their efficiency of transmission. Therefore, the central switch is connected in series to other critical components for Star Network RBD, as shown in Figure (b). The ring structure is like a cascade, but the last switch to the first switch forms a chain. This provides N-1 network redundancy against loss of communication links.

2.3.1: Cascading Topology

As shown in Figure 3, a communication network acts as the transmission format where all terminals are attached straight to the bus. The shared communication line (central core of bus) connects all links. Every IED is linked to the other in a cascading architecture with a direct link, and the architecture entirely resembles an open-loop chain (Das et al., 2014; Sidhu et al., 2008). According to Sidhu et al. (2008), the advantage of cascading topology is a straightforward hence easy in implementation and less costly construction. However, it would have a comparatively higher delay (latency) (Das et al., 2014; Pozzuoli, and Moore, 2006).

2.3.2: Ring Topology

Ring architecture is like the cascaded architecture but the circle is shut between the last switch and the first switch, as shown in Figure 2.6. As elaborated by Yang et al. (2013), the Ethernet Switches do not readily help circles. In architectural approach, fast crossing tree empowers working convention (802.1w) and utilisation of by microchip switches. As such, Zhang and Papachristodoulou (2013) outlined that it additionally enables topologies to respond rapidly in the event of a problem. As a result of the repetition of n-1, there is substantial potential for ring design to offer better dependability (Das et al., 2014). Along these lines, regardless of whether one of the ring associations or Ethernet switch (ESW) dissolves, IEDs can even now impart. However, the critics of the design argue that its design of transmitting data through all intermediate nodes presents a problem of failure of the entire network if single node fails. Importantly, any maintenance done to a node or a part of the large system means a overhauling the entire system because communication has to pass through all intermediate components. As such, it is largely contended on its applicability to the power network geared towards availability and reliability.

2.3.3: Star Topology

Figure 6 demonstrates an incorporated multimodal star-associated four-centre system comprising of 60 IEDs, four-channel centres, an Ethernet switch port, and a WIN framework server. All gadgets here are associated using a 1000-BaseT interface with a rate of 1000 parcels for each other exchange (Das et al., 2014). Each centre is associated with 15 different IEDs in this system. For this situation, in a coordinated power dispersion and transmission organise, customer Ethernet implanted workstations that could be a hand-off or shrewd controller. Considering this as a perfect case, every one of the four centre points is put in careful systems with a similar quality principle associated with an Ethernet passage switch, which thus makes an incorporated broad star-associated framework. According to Thatte & Mitra (2008) and Zhang & Papachristodoulou (2013), given the centralised nature of the architecture, its operation is easy, transfer of information is simple, fault detection is easy, and isolation of parts without interfering with the entire network is possible. Moreover, unlike ring setup, data packets do not pass all available nodes hence less data traffic. Nevertheless, the downside to this setup is reliance on functioning of the central hub. As argued by Thatte and Mitra (2008), any problem with central hub would render the entire system down. In addition to cost of setting up the system, adding a new node (part) depends on the capacity of the central systems. In large power substation or in the same sense, power grid, adding new feature such a substation to a grid demands upgrading the central hub or, in the substation case, expanding substation handling capacity like sampling adding a bigger transformer would mean restructuring to accommodate the new parts/ nodes.

3.3.3: Hybrid Topology

Hybrid architecture can combine several topologies depending on the need. According to Singh and Liu (2004), almost every IED in the design is associated with a hybrid topology switch connected to the Ethernet focal switch. Half and half topology give excess capacity and also shorten the length of the links. The exchange rate of information between the IEDs and the switches is much faster, and a negligible postponement occurs. Furthermore, as shown in Figure 2.8, each sub-switch of a star circle is associated with two additional adjacent sub-switches (centres). As pointed by hybrid topology combines the benefits of different topologies occasionally resulting in a very flexible, reliable, and scalable system. Studying a combination of star and centralised ring configuration, Nehrir et al. (2011) pointed that it offers benefits of both topologies such that power rating are centralised (central ring), fault can be isolated while ensuring power availability is at minimum, and minimizing the circuit lengths by connecting to the central ring.

3.3.4: Redundant Topology

Two redundant rings are associated with making repetitive ring design. The approach allows adding a counter-rotating ring where the data being transmitted is switched automatically across to the other ring in the event of failover of the primary ring. Scheer (1999) and Datta & Aberer (2006) highlight that such approach offers an extremely fast recovery. Figure 6 demonstrates that both of these rings are associated again in the ring of four key Ethernet switches. This kind of design gives normal inertness a total repetitive ring system. Quick spreading over tree empowered working convention (802.1w) oversaw microchip switches are hence required. This correspondence channel enables Ethernet centres to square and distinguishes rehashed circle messages from flowing on the up and up inside. It additionally empowers topologies to respond rapidly inside a data transmission problem. Given the n-1 redundancy; there is potential for ring design to offer better unwavering quality. Consequently, regardless of whether one of the ring associations or ESW comes up short, IEDs can even now impart (Das et al., 2014). According Datta and Aberer (2006), the design, in any case, is somewhat costly, muddled, and does not improve overall organise latency [IEC 60870-4].

2.4: Substation Automation Topology

In IEC 61850 substation, the communication standards is divided into three levels namely the process level, bay/unit level, and the substation level where data is shared within and between all components. The process level consists of IEDs, Ethernet switches, and input/output devices while the unit level comprises of control and protection devices. Substation level hold workstations, communication equipment, and interface as shown in the figure 9 below. The environment is designed over an object-oriented model supported by smaller units called Logical Nodes corresponding to physical devices (substation components) such as metering, transformers, circuit breakers, control, and monitoring functions.

Implementation substation automation topology can take configuration of Human-Machine Interface (HMI) based, Remote Terminal Unit (RTU) based, or Decentralised. Sayed and Gabbar (2017) indicated that in order to link the levels and remote SCADA system aimed attaining reliable sharing of data, powerful interconnection and communication protocols is paramount. In HMI based, the communication protocol is accompanied by powerful computer system particularly in a large substation to accommodate IEDs and data traffic. Practically, only one computer hardware is used in monitoring the IEDs, data handling issues, processing, and analysis. Essentially, as contended by Xu et al. (2014) and Cahn et al. (2013), this jeopardises the reliability and availability particularly when there is need to adequately and accurately predict such factors as maintenance. As such, most the approach is limited to the small substation accommodating limited number of IEDs and data traffic and computer failure can be handled simply. RTU based setting allows freeing the HMI computer to operate interface operations only rather than being tasked with automation process.

2.5: Interoperability and reliability of communication schemes using IEC 61850

In electrical power systems, the essential requirement for efficient operation is to improve the interoperability and availability of transmission of distribution protection schemes. Relay- to -relay communication allow a significant reduction in the overall cost of different protection schemes. According to Madan & Bollinger (1997) and Mellit et al. (2009), AI technologies in power systems has been a core aspects in advancing maintenance, fault detection, and load variation. Oualmakran et al. (2011) contended that the process ability of the AI to learning, acquire cognition, and self-correct has eased the load dispatch, optimisation of generation, scheduling, transmission capacity, and load forecasting. However, the heart of this success is largely grounded on the communication systems between parameters, sensors, and central analysing centre. Studying conventional communication system in smart grids, Bikmetov et al. (2014) found that implementation of an elaborate communication structure has grown into paramount aspect to support sophisticated computer systems, IEDs, and AI technologies. Currently, substation have communication data paths operating at more than 64kbits/s housed with data acquisition systems such as SCADA. Recently, according Kirrmann et al. (2011), implementation of High-availability Seamless Redundancy (HSR) allows power substation to have seamless failover against any failure.

2.6: Improve line guard schemes

Traditional protection is not valid for instantaneous tripping in all unsatisfactory situation, but the communication-based protection schemes allow to be tripping in more effective ways and reduce overall fault clearing timing. Doshi (2016) contended that during the period of fault does not require high-speed communication requirements, so these schemes signalling or transmit only on/off data from a local device to the main centre.

This scheme can be divided into three main groups (Apostolov, 2013).

Inter-tripping -breaker tripping work without any receiving end supervised. It requires to be secure. It is essential that any noise o the signalling channel is not seen as being a strong signal.

Permissive – command coincides with protection operation will give the tripping permission at the receiving end. As this is a second last step, it does not require much secure as inter-tripping.

It is blocking – in this system, tripping only permitted when the system does not receive any signal. A signal is used to prevent tripping, so it requires signals every time. It must be fast and dependable.

As pointed by Falahati et al. (2014), permissive is used under or overreaching schemes for distance element and directional comparison schemes for directional elements.

2.7: Implementation of accelerated schemes

Accelerated scheme is depended on the application requirements, available communication, and substation communication protocol. According to Ericsson (2010), serial communication line protection based on microprocessors has advantages such as comparing traditional ones such as improving performance and reliability by removing hardwire connections. An output of the communication device receiving the signal in the distant station is connected to the input relay receiving the exponential signal used by the protection system in the transmission network, as shown in Fig. 9 (Apostolov, 2013). In permissive schemes, fibre optic cable has used to accelerate data transfer speed between protection devices. However, only in the faulted phase, the non-judgmental signal is not going over.

In subsequent versions of the power system prevention relay based on microprocessors, rapid schemes were implemented without the use of a teleportation device. Figure 10 shows an expedited protection scheme for direct serial communication between the relays at both ends of the protected transmission line.

Implementation of an accelerated redundancy system to enhance the consistent reliability of the insurance system as shown in figure 11. Chakrabarti et al. (2008) argued that if there is a scheme for power line signalling between stations, the scheme logically is comparable to the one shown in Figure 2.11. Nevertheless, complicated cables between the protection devices relay outputs and the communication unit entries are substituted by GOOSE texts for virtual connections. Apostolov (2008) outlined that in the permissive directional comparison scheme above, the following GOOSE messages can be used as single communication:

The security IED must publish the guideline status to show the current state of the accelerated protection system.

The contact IED must report the receipt of the Permissive (Forward direction) signal from the remote end. This message is taken by the security IED to determine when the defect falls within the safety area.

The transmission line safety IED must publish changes in the state of the directional component. Send the communicational single to remote end to indicate communications device process.

The safety relay must report the maintenance comparison operation to signal to the breaker control device that the breaker must run.

The availability of fibre optic connections between stations allows for the use of goose texts between the safeguards that execute the scheme. Atienza (2010) reflected that the favoured decision for this considerate plan is because they do not have to hold onto a blocking signal from the far end, while the lenient flag does not pass the blame. As pointed out by Liu et al. (2011) and Falahati et al. (2014), this execution is accomplished by stretching out the substation LAN to the remote substation. This is characterised as "Tunnelling ". In the configuration in figure 12, every insurance 1 and assurance two gadget in the two substations, An and B buy into the tolerant messages from the remote stopping point. Zhang and Gunter (2010) lauded this arrangement because it enables the framework to deal with even a few instances of the disappointment of two insurance IEDs-one in substation An and one in substation B, accordingly, improving the dependability of the security framework.

2.8: Isolation of parameters

In this plan transmission and circulation lines, transformers capacitors every gear is secured by the defensive transfer which is intended to give essential assurance of individual substation hardware. According to Macwan et al. (2016), numerous defensive IEDs with IEC 61850 GOOSE can be connected to the LAN station and utilised for appropriation diverts in decentralised transmission of applications. The feeder assurance IED will see a deficiency in case of a flaw on any of the secured feeders (F1 in Figure 13). The transformer insurance IED will see a similar deficiency current. When the feeder transfer's overcurrent defensive component starts, the IED will send a GOOSE message showing an issue recognition on the feeder. In a distributed transport assurance application, different defensive IEDs with IEC61850 can be associated.

2.9: Switched Ethernet-based station-bus IN GOOSE messaging

GOOSE messages defined by an integrated power station prevention and control system centred on IEC 61850. Defined as the standard IF8 interface is used for fast interlocking in peer-to-peer communications. Study conducted by Vasel (2012) based on Ethernet architecture supported by GOOSE messaging systems demonstrated that, this can achieve 4ms for communication using state-of-the-art technology hence energy efficiency gains can be attained through frequency drives, improved power consumption, and substation visibility as well as faster problem diagnosis and solving. Zeynal asserted that networks communication have become part of interconnected control systems of the SAS. They have distributed handling and control benefits from networking capabilities in digital SAS systems, making it useful for local power protection and automation communications. Forouzan (2007) held that Ethernet’s first step in evolution was to use the bridging concept to increase bandwidth by 3 and separate collision domains. Switched Ethernet is a bridged LAN extension that eliminates collisions and enables faster transmission of Ethernet and full duplex.

The GOOSE message frame utilises an IEEE-characterized layer two casing expansion called 802.1Q, as appeared in Figure 2.20. The IEC61850 section 7-1 characterises the Conventional Item Arranged Substation Occasion. This message is ordered inside the execution of type1, which means quick message conveying changes in status and occasion. Among these characterised messages are Type 1-An, a primary mission requiring under four milliseconds of ETE delay. Along these lines, a reaction time inside under four milliseconds is required for a superior class of insurance (prospective relay) necessities (Choi et al., 2012). GOOSE has worked inconsistent quality originates from retransmitting the message edge as far as possible of its life utilising a predefined field called Time Allowed To Live (TATL property). The base and most final retransmission period will decide the transmission time of GOOSE. The most extreme edge measure relates to the most magnificent IEEE 802.1p/q exemplification Ethernet outline (Fig. 2.20), i.e., Ethernet measure rises to 1822 bytes with need labelling and VLAN fields. GOOSE correspondence will be influenced by individual variables, including switch texture and exchanging innovation, network media, available transmission capacity, traffic design (Xu, 2009; Altaher et al., 2015; Haffar et al., 2007). GOOSE administration would profit by the capacity to label Ethernet needs to upgrade time-basic need necessities. The standard suggests that GOOSE needs to be higher or equivalent to level four (up to seven). GOOSE outlines have an Ethernet-type (Fig. 2.20) that rises to hexadecimal number 0x88b8. System analysers perceive GOOSE outlines by their Ethernet type field.

2.10: Fault location, isolation, and service restoration (FLISR) technique using IEC61850 GOOSE

Applying distribution automation applications to improve situational awareness and reduce the financial penalties, which occur due to the system outage. Parikh et al. (2013) and Spalding et al. (2016) highlighted that Fault location, isolation, and service restoration (FLISR) system can expressively reduce the outages at the end customers. Once FLISR installed in the distribution system, it can reduce approximately 3-4 hours per outage as compared to without the FLISR and greatly enhance the distribution grid reliability by quick response restoring (Kanabar and Sidhu, 2009).

2.11: FLISR fault clear steps

Fault location- To find the fault first for the FLISR, which triggered by the substation protection devices. Once the fault location found, the feeder is referred to as a portion between two switches.

Fault Isolation- After the fault identification, both sides of fault need to be isolated using the switches.

Capability estimation- After Separation and before rebuilding capability estimation, the process needs to be carried out.

Service restoration- Capability estimation process, we will come to know that which feeder is capable of taking more load until healthy feeder. Service restoration process closes the switches and connects healthy feeder to faulty feeder.

2.12: FLISR Architectures

Centralised FLISR (C-FLISR): In this system, each switch needs to communicate control center directly; it requires a high bandwidth communication network.

De-Centralised FLISR (DC-FLISR): Device installed in each sub-station. This system is faster than C-FLISR with lower bandwidth requirement.

Distributed FLISR (D-FLISR): This process controls each switch location and determines the appropriate switching actions necessary for restoration. This requires a controller at each switch location.

2.13: Using IEC 61850 GOOSE Messaging: Transformer load tap changer control

According to Sichwart et al. (2013), Goose messages are utilised for multicast shared correspondence among IEDs and correspondence among IEDs and the substation PC. With goose messages, many information traits consolidated in a dataset can be conveyed (Yarza, and Cimadevilla, 2014; Ingram et al., 2013). Different gadgets buy in to and read the goose message to recover the data. In additional, LTC engine works by actuator module for get the order to do as such from the control unit utilising IEC 61850 GOOSE. However, Yarza and Cimadevilla (2014) pointed that voltage estimation ought to be contrasted and examined values messages. In this framework, every transformer has its IED for assurance and control, which likewise incorporates the LTC control. IED is legitimately associated with live wires yet proposed required information conveyed through IEC 61850 GOOSE messages.

2.14: Load tap changer

Load tap changer is a kind of system used to change the number of turns in a transformer winding. LTC fitted auxiliary side of the transformer to keep up the voltage level. As pointed by Sichwart et al. (2013), it may be constrained by the SCADA framework from a control focus. Variable LTC_R and LTC_L utilised as the controller. LTC_R control the upper capacity; it stays high for 0.5 seconds as dictated by the raise beat clock. LTC_L controls lower-tap capacities (Sevov et al., 2011; Yarza, and Cimadevilla, 2014; Zhao et al., 2011). Tap position number "tap pos" is determined to utilise a math variable SELogic Condition with condition TAP POS=8.00+UP COUNT- DOWN COUNT. The counter-programmed reset at whatever point the tap position check rises to 8 with the end goal that the quantity of tasks is not restricted.

Research Methodology

3.1: Introduction

This chapter explains the calculation of power system networks methodology to analyse the availability and reliability of the transmission system using IEC 61850. OPNET software or Riverbed Modeller was used for system configuration and obtained the results. The following architectures were simulated and analysed using the OPNET. Reliability block diagrams can be used to calculate the reliability and availability of the different communication topologies for substation automation. Reliability and availability are based on intelligent electronic devices (IEDs). Monitoring, controlling and protection in a substation system using fever devices had been possible in various implementations. A more straightforward design has some difficulties has been overcome in the modern microprocessor substation automation system to reduce hard wiring to reduce some cost. The key component of this research is ways in which IEC 61850 communication protocol had improve power network reliability and availability. The simulation focused on detection failure rate, isolation, and maintenance detection, and handling of transmitted data (GOOSE messages) collectively framed towards system reliability and availability. Communication for the Substation Automation System using Ethernet-based network and IEC 61850 were configured. Some of the critical signals need to be communicated within the required time, as stated in IEC61850 and incorporation of Ethernet enables fast communication to meet requirements such as a trip signal.

Substation automation model required a four-step connection to operate

Station level 2)

Bay level

Process level and

HV equipment.

3.2: Equipment required

The following equipment and tools were required to measure reliability and availability in power system based on IEC 61850 communication protocol.

Personal computer

IEC61850

Microprocessor-based controllers of power system equipment, e.g., circuit breaker, protective relay

OPNET software (Riverbed- new edition)

Riverbed Modeler helps to simulation and modelling environment for power network equipment and communication protocols. Riverbed used in power industries to design model of transmission Network technology and designer can model to analyse system cost and reliability. This software reduces the need for expensive hardware prototyping and time-intensive. A limited-feature version is available for pedagogical users who wish to use Networking classes with simulation software. Riverbed Modeler Academic Edition includes instruments for all research stages including model development, simulation, and information collection and information analysis. Modeler Academic Edition is a substitute for the IT Guru Academic Edition.

Figure 18 is laboratory setup for IEC61850. Hardwire cable connection used between distance relay and test set machine. Ethernet switch is used between operating pc and distance relay using fibre optic cable. This is a simple connection lay out of IEC61850 in Lab. On operating field, it is bit more complicated and more accurately connection required.

In data collection and analysis, several players were directly and indirectly involved.

Organisation (s) part of the project: Central Queensland University

Power industries in Australia are using IEC61850 for a communication system.

Power transmission companies. Bass link power transmission Vic, Transend Tasmanian transmission company, Direct link Queensland power Transmission Company.

3.3: IEC 61850 Goose Messages for the Proposed Flisr

Goose message accompanies two-level security controllers. Building from Parikh et al. (2013) assertion, on the off chance that the lock-out breaker is not quickly adjoining the issue, there is another downstream that sense the deficiency and lose control after lock-out. The associated number field (sqNum) and timeline (t) are recognized for the GOOSE outline. The ETE delay is regulated by the removal of time signals from the progressive distributor and endorser outlines with the corresponding amount and distinctive time signs. To ascertain the postponement, the accompanying formula is used:

Tdelay = Tdes – Ttr (1)

Where Tdelay is deferred time, Tdes is timestamp at endorser IED, and Ttr is timestamp at distributer IED. Delta time (dormancy), for caught outlines, is estimated inside microsecond accuracy. At long last, the standard deferral is figured by the quantity of caught outlines amid the test time frame. This healthy esteem is determined by partitioning the general postponement by various edges.

3.4: Analytical Calculation and Assumption

Surveying the productivity of substation control frameworks are centred around execution-related estimations and elucidation of accessible test information under certain or re-enacted conditions. The information is administered by a parametric appropriation of likelihood, which speaks to the probability of disappointment of the given framework inside a predetermined time. Disappointment rate λ is the estimation of the prompt disappointment rate per unit time. For the numerous physical parts, the ordinary disappointment rate bend has a bath bend shape that can be separated into three reigns. Because of assembling mistakes or inappropriate structure, Area I (consume in) is described by an alternate higher disappointment rate. The destroy period of region III shows a quickly expanding rate of disappointment after some time. Region II (valuable life) is a routine task portrayed by a steady rate of disappointment. The disappointments are free of one another, making Poisson and quickening conveyances substantial for both the count of dependability.

3.5: Testing

For testing used state sequencer feature of the Omicron test universal software and send that data to 3-phase voltage simulating line voltage and receive two binary inputs after a tap-raise and tap-lower operation using LTC-R AND LTC-L. A first operating timer was expected to be 30seconds and the second operating tap raise timer is set on 5 seconds is expected. LTC controls not a time-critical it includes 1.37 second on every expected time frame which we set in it. This delay occurs because of measuring and communicating the voltage value before it is available for the logic (Sichwart, Eltom and Kobet, 2013).The goal was to achieve full implementation control of IEC61850 in LTC control.

3.6: Description and scope

A classic technique for the methodology for modelling of IEC 61850 based assurance frameworks is introduced. Supports a far-reaching set of substation capacities. In this plan transmission and dissemination lines, transformers capacitors every gear is ensured by the defensive transfer which is intended to give essential security of individual substation hardware. In disseminated transport insurance application, numerous defensive IEDs with IEC61850 were connected. Nevertheless, choosing the components was based on the individual component failure rate measured over time. Failure rate, as captured by bath-tub curve shown in the diagram below, decreases for a while then remain constant before increasing as time goes.

In a reliability-Based Protection System Layout using IEC 61850, the integrated power transmission system consists of the physical components (transmission lines, transformers, circuit breakers, etc.) and Ethernet switches, merging units, protection IEDs, etc. These components have different failure rates as shown below.

In the following table, failure rate listings of the reliability data for individual components.

In this research, typical value of MTTF 100 years was chosen. The ES and protection IEDs on the same protection panel are combined into a single line protection unit in order to facilitate the analysis. Redundant protection IEDs are typically equipped for each protection unit. Thus reliability shown in the block diagram in Fig22, both the IED protective systems are displayed simultaneously and in series with the ES.

Based on the Ali and Hussain (2017) observation in that different topologies and network have different communication handling spend, components, packet sizing, and destination, the following table informed choosing on the topology and network to be used.

As per past research and current distribution system, hybrid topology has widely used the network, so implementation of this project will be on Hybrid network. IEC 61850 will use in hybrid topology power transmission connection to improve reliability and availability of power transmission line. GOOSE messages generally carry data about time-critical occurrences such as Trip, Close, Start, Stop etc. in IEC 61850, and are therefore mapped directly to the Ethernet layer. Likewise, SVs are a stream of MUs synchronized data packets. They will also be mapped effectively to the broadcast/multicast covering Ethernet layer.

Constraint

As this project is on simulation-based, it requires a knowledge of algorithm, OPNET (Riverbed) software, and the calculation. Using IEC61850 requires an Ethernet network. This system needs maintenance by a skilled person.

Simulation Results and Discussion

4.1: Introduction

This chapter concludes the simulation of the network system and sample results from previous verified researches. Furthermore, details will be discussed and simulate in the implementation part. Simulate different technique gives different output, so after measuring different component and using different connection can find improve transmission system. Taking all recreations for both simulations for both hybrid architectures, it was seen that for Star-ring open hybrid topology, the deferral in information transmission was around 0.8-1.4ms. As examined in this paper, the postponement is moderately lower than some other topology. As the crossover Star-ring open topology meets IEC 61850 similarity criteria including high repetition and proof of zero-point disappointment, it is the best fitting engineering for PSC between the SASs.

4.2: Line protection and isolation of components

Mean time to fail (MTTF), Mean time to repair (MTTR), Mean time between failures (MTBF) is used to represent or calculate the system reliability and availability. The accurate portrayal of the information should be possible utilising one of the likelihood conveyances works that have a place with the group of appropriation capacities varying just by the estimations of their parameters.

The system reliability and probability of failure are calculated from the below equations,

Qt=0tf(t)dt (1)

Rt=1-0tf(t) (2)

Qt=0te-λtdt=1-e-λt (3)

Rt=te-λtdt=e-λt (4)

Et=0(λ t.e-λtdt=1) (5)

In MTTF

Q(t) is the cumulative failure distribution function, E(t) is the mean time, and R(t) represents the reliability over time t.

Safety probability was as below

Normal operating state = V1

When an error happens, it happens with rate M, and it leads to state = V2

If IED installed in the system, it took the system to a safe place with rate B and it leads to state = V3

Coming back to the normal state with rate N

V1 and V3 is safe to state

V1+V3=1-V2 (6)

As V2 is an unsafe state probability of safety

S=V1+V3=1-V2 (7)

Expressing unsafety probability V2 as

V2 = 1S (8)

V2 = 1/1+BM+BN (9)

In the result of safety probability S as

S= 1/V2 (10)

S=1/1/1+BM+BN (11)

Based on the scheme below, figure 3.2, as the tripping signals must only pass through insulated wires for the CB, the implementation of Ethernet switches is without impact and will not be included in the estimates of reliability. Ideally, the quality of security will be influenced by the type of IED used. In the IEC 61850, the definition of multi-functional IEDs was implemented.

4.3: Simulation Setup

The tunnels were configured between routers by setting the correct attributes in the router nodes for OPNET simulation. Two routers informed various networks, for example, have a tunnel. The substation one and DER plant1 set the various router node attributes in the IP routing attributes. When a tunnel between two nodes is created, traffic is transmitted from one network to another without needing IP layers. The encapsulation and isolation of messages at the beginning and end of the tunnel leads to a large amount of ETE (END to END) lag.

As shown in figure 26, hybrid topology has two redundant Ethernet ports, each with two redundant bay switches in a star-setting configuration connecting all IEDs for every bay. Also, the ring configuration of all bay switches is related. This would mean that redundant ESs per bay are parallel and the ring configuration is shown to be associated with other essential components separately in sequence. Since each ring provides N-1 redundancy, for Interbay communications, only 6 out of 7 Ethernet switches are needed. We can, therefore, conclude that hybrid topology among them is good topology.

Figure 24 shows the hybrid architecture RBD, which suggests that all Ethernet bay switches are directly connected to both redundant Ethernet switches and central switches. Hereafter, all hub sub-switches are linked in series and simultaneously.

The redundant architecture of the ring provides an improved rate of data transfer, although absence a standard protocol and approach presents interconnection challenge and may result in data losses.

The MTTF star-ring and the A star-ring, respectively, are 15 years and 0.9999513 from the RBD calculations (Das, Modi and Islam, 2014). In combined Star-Ring architecture, each bay-level Ethernet switch is directly connected to two redundant primary Ethernet switches in the star-ring LAN architectural design. Figure 30 shows the connection in the ring of these main Ethernet switches, which gives both higher redundancy and low latency. However, the star-ring configuration requires two additional switches. Based on the argument posted by Kim et al. (2010), although the approach tries to accommodate the shortcomings of both the star and ring topologies, the increased cost of setting up that include the equipment and structure as well as different designs followed by different vendors makes implementation difficult.

4.4: Reliability in the Network

The reliability of the wide-range communications network depends not only on the reliability of the components but also on the detection and servicing levels; it would ensure smaller availability and higher CFPs (C form-factor Pluggable), with longer inspection time, which presents a drawback to the system's capacity to perform its sufficient function under the conditions indicated.

Reliability data after combination for protection unit shown in table 3.

Although the recovery time can be as low as 3ms and can tolerate failure from a single point node, absence of standardized design and protocol present a challenge of interconnecting independent layout such as substation to the grid or even different section of a substation. The findings by Das et al. (2014) show that the MTTF redundant-ring and its failure rate are 0.9999878 years and 16.89 years, respectively from Figure 2.8, the RBD calculations.

The multi-functional Key and Backup protection IEDs are presumably 100 years MTBF (Kasztenny at el.) (Z=1-1/100=0.99) and are connected in parallel. Protection function reliability in the result is 99.99% (X=0.9999), for an average downtime of 52.56 minutes.

As shown in table 5 from the RBD. The calculations for MTTF cascaded and a cascaded are 8.85 years and 0.9999330, respectively.

The simplified blocks are shown above. Assuming that the CB device has primary equipment reliability of MTBF = 1123 years (Y = 1-1/1123= 0.99911) (L.R. Castro Ferreira, 1999), the overall line protection scheme availability is 99.90% (X*Y). The average downtime per year is 8.67 hours. This project-based on topologies used as simulation with IEC 61850 and measured results. All topologies have different output and different costing. All this factor depends on power demands for consumer and supplier distribution system. Among those topologies cascading topology is simple and less cost-effective but its MTTF 8.85 years. A hybrid topology is more costly as compare other topology, but it gives more MTTF such as 12.63 years. These are the previously verified data; we need to improve more reliability and availability in the power transmission system. More different type of topology and other types of a communication system using IEC 61850 will be compared in the implementation part.

4.5: Network configuration with sample results.

Star architecture

From the star topology simulation, an average load on nodes, delay time was tested. This data helps to make the system more stable. Simulation in OPNET to get data for the system which will help to calculate MTTF and availability. Calculating the result from RBD MTTFstar and Astar is 6.92 years and 0.9999208 years, respectively.

Figure 32 shows the average load on the system time vs load as can see; it is increasing over time. The system was ran for 30 mins after a few minutes load rises suddenly and increasing continuously.

The reliability and the availability values for the Star architecture as follows,

MTTF= 6.923076923076923 y

A= 0.999920852285497

Ring Topology

It is likewise seen that ring engineering has a lower time delay for exchanging information messages than the falling design. From the RBD of ring engineering, the MTTF ring and A ring are determined to be ~12.17 years and 0.9999513, individually (Das, Modi and Islam, 2014). Figure 33 shows the average load on Ring topology system time vs load as can see. The simulation was ran for 3 mins after a few minutes load decreases suddenly and reducing continuously. The findings showed that system time vs load increases over time.

The reliability and the availability values for the ring architecture system as follows,

MTTF= 7.627118644067796 y

A= 0.999920852619063

As shown in Figure 22, ring topology, switching repeaters in a closed-loop connects together. Topology Ring LAN guarantees high reliability and fast isolation based on fault recovery. If the error occurs on one computer or cable, the communication system continues to work. The topology of the network modified into a topology of the stars. Ring topology is commonly fitted with repetitive devices that support large substations. The topology was found to be not appropriate for time-critical messages without priority marking. Generally, the Ethernet switch does not allow loops, in which a loop that affects the bandwidth of the transmission can still exchange messages. Therefore, a regulated switch should be used to detect loops and block messages internally from circulation via loops, using a related RSTP protocol specified in IEEE 802.3w. In the unsatisfactory case, it also permits the LAN configuration.

Hybrid configuration

As discussed in this research paper hybrid topology is much responsive and reliable but bit expensive while other discussed topology is easy to install and less expensive but have less reliability and availability. Hybrid topology was set up in simulation to get better results and try to improve the reliability and availability of the system.

Figure 35 shows the simulation setup for GOOSE messages for performance measurement. Where safety relay(s), a PC and experiment set are linked to an Ethernet switch to build a network of communication. The following steps are involved in an execution system for performance calculation of security relays based on IEC 61850 and the related privacy schemes. In addition, comparing Ethernet delay with the star topology shows that variation in delay is much less in a hybrid topology network system as the hybrid topology achieves required criteria for the IEC61850. This system is less failure and high redundancy rate.

As per figure 36, Average delay in a hybrid topology is less than other topology. Response time in hybrid topology is quicker as compare ring or star topology network system. After the simulation of hybrid topology, it indicates delays in data transmitting is between 0.7-0.9ms which is lower than all other topology used in this thesis. As compare previous hybrid topology results with this topology, we achieved more reliable and available topology. In this hybrid topology star, ring and tree connections used to get better reliable and stable power networks. Compare to the previously verified hybrid topology get 0.8-14ms for star-ring open hybrid topology (Das, N., Modi, H. and Islam, S. 2014).

Figure 37 indicates that the data transmission rate was higher in hybrid topology compare another topology. Respectively higher data transmission and less delay time indicate the system performance is better than another network system. Using hybrid topology data transmission rate is higher than start topology where hybrid topology and star topology data transmission is 42packet/sec and 30 packets/sec respectively.

These knowledge-based systems applied to the modern power systems that include Artificial Neural Network (ANNs), Expert System Techniques (XPSs), and Fuzzy Logic Systems (FL) improves proficiency and competence. High cost of putting up distribution lines and infrastructure in addition to regulations particularly in the era of diversifying electricity power mix (different sources connected to national grids) and rise of mini-grids have forced shared distributed generation. The major problem with distributed systems is that such structured were not designed to withstand current diversification and ‘peaker plants’. Therefore, as a solution to this heightening demand of power and need for reliability of power while avoiding a cascading catastrophe is implementation of automation and interconnection of various systems to the network such as ‘smart grid’. As a supporting structure, the interconnected systems from different vendors and mini-grids have to communicate with each other. Hence, grounds for developing and structuring communication protocol. According to findings, complexity, versatility, and data bulk as well as need for better data computation time period and accuracy in the power networks and systems have prompted increasing moving away from conventional techniques and adoption of new approaches such as AI and Automation.

Conclusion

In this chapter presents the overall summary of the research and the concluding remarks. It also includes further recommendations for improving system stability and topology connections for better results. Although, over the past decade, literature on IEC 61850 and automation of the power network including applicability, functionality, benefits, and drawbacks, there is still concerns on specifying the best standards in automation especially partnering the reliability and availability of power in a network. Due to these shortcomings in preventive and reactive maintenance approaches, condition-based was developed in 1980s. This founded on the idea of regular inspection but maintenance done only when needed based on the set standards. For instance, in a belt-driven equipment, a belt can only be replaced when it start squealing. Nevertheless, the approach relies heavily on the indicators set of need for and interval of the maintenance. Recently, due to the critically of some industries, there has been demand for an approached focused on more reliability and availability of service. Increasing reliability of electrical power by critical industries has forced power plant operators to take reliability- and availability-centred maintenance. In this technique, maintenance operations are taken based on the risks and on analytical processes. Its foundation on the analytic techniques and automation has led to adoption and perceived as a reliable technique. Such systems as Supervisory Control and Data Acquisition (SCADA) take a central role in monitoring state and operation of the equipment but need a compact communication structure to work smoothly. Through standardization of the communication and data sharing processes and structures, as pointed below, IEC 61850 protocol allows re-engineering of traditional monitoring, protection, and control as captured by implementation of SAS. Although, over the past decade, literature on IEC 61850 and automation of the power network including applicability, functionality, benefits, and drawbacks, there is still concerns on specifying the best standards in automation especially partnering the reliability and availability of power in a network. The usage of the IEC GOOSE gives a quicker start to finish interconnectivity than utilising designing. Displaying and recreation approaches were directed utilizing OPNET Modeler In where a straight feeder model was made, and a need plot was embraced. Findings show the block diagram and it analysed the communicating design of the test transmission scheme in OPNET software environment. The efficiency of the communication design is explored for different critical functions, essential tasks mentioned in the below table. Large IP networks (such as ATMs, SONET and Frame Relay) using tunnelling techniques and R-SV and R-GOOSE facilities. A couple of routers form a tunnel to each end of the WAN connection in the tunnelling method. They use TCP / IP protocols to wrap and unwrap GOOSE and SV messages. The tunnel can be used to convey any sort of message to another WAN end.

Project is about studying IEC61850 for the transmission system. With IEC 61850, a lot of copper cables has been saved and hence a lot of money, and at the same time, it makes the substation automation system more flexible, robust and more intelligent. Possible suggestions for future studies that will further improve the work undertaken in this thesis. The multilevel safety system can be enhanced with this study to improve the reliability and availability of the transmission system. Multi-vendor interoperability has been proved. IEC 61850 will be the choice protocol as utilities move to the substation and beyond network alternatives. Using the IEC61850 system is self-monitored; it makes the system more convenient and routine re-verification without system interruption. Experiments and various topology design will be done in the implementation part. Focus for study IEC61850 in Hybrid topology as this is a widely used networking system, and it required more to get a more stable network. This result clearly indicates which type of topology must be applied for the power transmission system to improve reliability and availability of automation functions. Ring topology connections connect nodes, which are arranged for one closed route in a ring topology. Information passes from node to node around the ring. Ring-topology installation is simple, and link failure can be recognized readily. A redundant networking environment and collision-free are provided by the ring topology. If one connection fails, the entire network falls in this topology. However, it may be complex to add a current device to a current physical ring network, as every new device must interface with modern appliances. Collision free and redundant networking environment is provided by Ring Topology. Due to its high cost, it is not as prevalent as other topologies. Communication protocols based on IEC 61850 standard provide substation automation with novel solutions that also offer efficient performance. This efficiency enables real-time data sharing, lifecycle costs reduction, as well as providing interoperability, which has been identified as one of the most important motives for using it. Serial asynchronous communication and traditional the protocols currently in use need reform. Substation research Discusses the lag of Ethernet interaction, effect factors, different network approaches and topologies that can be developed in real time. Using OPNET software, the network delivery process of the simulation design is implemented. Ethernet delays the golf process performance; the results of the network simulation are analysed based on which switch, share Ethernet or peer-to-peer network. New substation systems are equipped with IEDs that mainly consist of protective relays based on microprocessors, measuring devices, programmable logic controllers, fault recorders, event recorders, and so on. Automation of the power system using IEDs means that power systems are monitored continuously, including modular hardware design, programmable logic capabilities, built-in software relay tests and the availability of continuous increase in non-protective functions. It is essential to use a particular time reference in all SASs to handle complicated duties properly and to monitor compliance in the station. This breakthrough design of power transmission using IEC 61850 will help to get better performance and high successful fault clearance ratio. Easy to install and with specific design best and most economics well. This research project results depend on simulation and previously verified data sources. Simulation is performed using OPNET (Riverbed) software, it allowed full access in modeler 17.5 version, and it gives more accurate real-time results as compare the other simulation software.

5.2 Recommendation for Future Works

As per current power generation, IEC 61850 protocol is able to improve the reliability and availability of the power system networks in future. The IEC 61850 specification has many different parts, some of which even among field experts are extremely difficult to grasp and interpret. This intelligent device is used for improving communication only by part of the country or some businesses. Interactive between clients and markets in real-time communication and control functionality optimised to ensure maximum reliability, accessibility, effectiveness, effectiveness and financial performance against strikes and natural disruptions. Through this growth, intelligent transmission grid can provide sophisticated EMS (Electric-power Management System) and asset management. This system is not fully developed; it needs some more research and modification to achieve future demands. Using the Hybrid topology connection and proper protection system, this can be achieved.

Reference

Aftab, M., Roostaee, S., Suhail Hussain, S., Ali, I., Thomas, M. and Mehfuz, S. (2018). Performance evaluation of IEC 61850 GOOSE-based inter-substation communication for accelerated distance protection scheme. IET Generation, Transmission & Distribution, 12(18), pp.4089-4098.

Ali, I. and Hussain, S. (2017). Control and management of distribution system with integrated DERs via IEC 61850 based communication. Engineering Science and Technology, an International Journal, 20(3), pp.956-964.

Ali, I., Thomas, M.S., Gupta, S. and Hussain, S.S., 2015. IEC 61850 substation communication network architecture for efficient energy system automation. Energy Technology & Policy, 2(1), pp.82-91.

Altaher, A., Mocanu, S. and Thiriet, J.M., 2015. Evaluation of Time-Critical Communications for IEC 61850-Substation Network Architecture. arXiv preprint arXiv:1512.07004.

Amjady, N. and Daraeepour, A., 2010. Midterm demand prediction of electrical power systems using a new hybrid forecast technique. IEEE Transactions on Power Systems, 26(2), pp.755-765.

Apostolov, A. (2013). Impact of IEC 61850 on the interoperability and reliability of protection schemes. IEEE, pp.1-5.

Apostolov, A.P., 2008, April. Implementation of accelerated transmission line protection schemes in substations with IEC 61850. In 2008 IEEE/PES Transmission and Distribution Conference and Exposition (pp. 1-6). IEEE.

Atienza, E., 2010, March. Testing and troubleshooting IEC 61850 GOOSE-based control and protection schemes. In 2010 63rd Annual Conference for Protective Relay Engineers (pp. 1-7). IEEE.

Baoyi, W.A.N.G., Min-an, W.A.N.G. and Shaomin, Z.H.A.N.G., 2013. A secure message transmission method based on GCM for smart substation. Automation of Electric Power Systems, 37(3), pp.87-92.

Besnard, F., Fischer, K. and Bertling, L., 2010, October. Reliability-Centred Asset Maintenance—A step towards enhanced reliability, availability, and profitability of wind power plants. In 2010 IEEE PES innovative smart grid technologies conference Europe (ISGT Europe) (pp. 1-8). IEEE.

Bikmetov, R., Raja, M.Y.A., Kazi, K., Chowdhury, B. and Zaidi, S.M.H., 2014, December. Role of PONs with the conventional communication systems used in today's smart-and MicroGrids. In 2014 11th Annual High Capacity Optical Networks and Emerging/Enabling Technologies (Photonics for Energy) (pp. 120-124). IEEE.

Bouhafs, F., Mackay, M. and Merabti, M., 2011. Links to the future: Communication requirements and challenges in the smart grid. IEEE Power and Energy Magazine, 10(1), pp.24-32.

C. M. De Dominicis, P. Ferrari, A. Flammini, S. Rinaldi and M. Quarantelli, "On the Use of IEEE 1588 in Existing IEC 61850-Based SASs: Current Behavior and Future Challenges," in IEEE Transactions on Instrumentation and Measurement, vol. 60, no. 9, pp. 3070-3081, Sept. 2011. DOI: 10.1109/TIM.2011.2158159

Das, N., Modi, H. and Islam, S., 2014, September. Investigation on architectures for power system communications between substations using IEC 61850. In 2014 Australasian Universities Power Engineering Conference (AUPEC) (pp. 1-6). IEEE.

Doshi, D. A. (2016). Real Time Fault Failure Detection in Power Distribution Line using Power Line Communication. International Journal of Engineering Science, 4834.

Fischer, K., Besnard, F. and Bertling, L., 2011. Reliability-centered maintenance for wind turbines based on statistical analysis and practical experience. IEEE Transactions on Energy Conversion, 27(1), pp.184-195.

Gajic, Z., Aganovic, S., Benovic, J., Leci, G. and Gazzari, s. (2010). Using IEC 61850 analogue GOOSE messages for OLTC control of parallel transformers. In: International Conference on Developments in Power System Protection. IEEExplore.

Haffar, M., Thiriet, J.M. and Savary, E., 2007. Modeling of substation architecture implementing IEC 61850 protocol and solving interlocking problems. IFAC Proceedings Volumes, 40(22), pp.291-294.

Ingram, D.M., Schaub, P., Taylor, R.R. and Campbell, D.A., 2013. System-level tests of transformer differential protection using an IEC 61850 process bus. IEEE transactions on power delivery, 29(3), pp.1382-1389.

Kanabar, M. and Sidhu, T. (2009). Reliability and availability analysis of IEC 61850 based substation communication architectures. 2009 IEEE Power & Energy Society General Meeting, pp.1-2.

Khosrojerdi, A., Zegordi, S.H., Allen, J.K. and Mistree, F., 2016. A method for designing power supply chain networks accounting for failure scenarios and preventive maintenance. Engineering Optimization, 48(1), pp.154-172.

Kim, J.Y., Park, J., Lee, S., Kim, M., Oh, J. and Yoo, H.J., 2010. A 118.4 gb/s multi-casting network-on-chip with hierarchical star-ring combined topology for real-time object recognition. IEEE Journal of Solid-State Circuits, 45(7), pp.1399-1409.

Andersson, K. Brand, C. Brunner and W. Wimmer, "Reliability investigations for SA communication architectures based on IEC 61850," 2005 IEEE Russia Power Tech, St. Petersburg, 2005, pp. 1-7. DOI: 10.1109/PTC.2005.4524707

Liu, Y., Gao, H., Gao, W., Li, N. and Xiang, M., 2011, September. A design scheme of line current differential protection based on IEC61850. In 2011 IEEE Power Engineering and Automation Conference (Vol. 2, pp. 520-523). IEEE.

Macwan, R., Drew, C., Panumpabi, P., Valdes, A., Vaidya, N., Sauer, P. and Ishchenko, D., 2016, July. Collaborative defense against data injection attack in IEC61850 based smart substations. In 2016 IEEE Power and Energy Society General Meeting (PESGM) (pp. 1-5). IEEE.

Mellit, A., Kalogirou, S.A., Hontoria, L. and Shaari, S., 2009. Artificial intelligence techniques for sizing photovoltaic systems: A review. Renewable and Sustainable Energy Reviews, 13(2), pp.406-419.

Nehrir, M.H., Wang, C., Strunz, K., Aki, H., Ramakumar, R., Bing, J., Miao, Z. and Salameh, Z., 2011. A review of hybrid renewable/alternative energy systems for electric power generation: Configurations, control, and applications. IEEE Transactions on Sustainable Energy, 2(4), pp.392-403.

Palmer, C.R. and Steffan, J.G., 2000, November. Generating network topologies that obey power laws. In Globecom'00-IEEE. Global Telecommunications Conference. Conference Record (Cat. No. 00CH37137) (Vol. 1, pp. 434-438). IEEE.

Phoothong, N., Vanittanakom, P., Teera-achariyakul, N. and Rerkpreedapong, D., 2008, May. Optimal preventive maintenance budget setting for electric power distribution utilities. In 2008 5th International Conference on Electrical Engineering/Electronics, Computer, Telecommunications and Information Technology (Vol. 2, pp. 957-960). IEEE.

Sayed, K. and Gabbar, H.A., 2017. SCADA and smart energy grid control automation. In Smart Energy Grid Engineering (pp. 481-514). Academic Press.

Sidhu, T.S., Kanabar, M.G. and Parikh, P.P., 2008, December. Implementation issues with IEC 61850 based substation automation systems. In Proc. National Power Systems Conference (NPSC), IIT Bombay.

Spalding, R.A., Rosa, L.H., Almeida, C.F., Morais, R.F., Gouvea, M.R., Kagan, N., Mollica, D., Dominice, A., Zamboni, L., Batista, G.H. and Silva, J.P., 2016, October. Fault Location, Isolation and service restoration (FLISR) functionalities tests in a Smart Grids laboratory for evaluation of the quality of service. In 2016 17th International Conference on Harmonics and Quality of Power (ICHQP) (pp. 879-884). IEEE.

Xu, W., Xu, G. and Yuan, H., 2014, September. High performance distributed power quality monitoring IED used in smart grid. In 2014 China International Conference on Electricity Distribution (CICED) (pp. 706-710). IEEE.

Yarza, J.M. and Cimadevilla, R., 2014, April. Advanced tap changer control of parallel transformers based on IEC 61850 GOOSE service. In 2014 IEEE PES T&D Conference and Exposition (pp. 1-5). IEEE.

Zeynal, H., Eidiani, M. and Yazdanpanah, D., 2013, December. Intelligent Control Systems for Futuristic Smart Grid Initiatives in Electric Utilities. In Conference Paper· January (pp. 315-319).

Zhang, F., ZHU, Z.H., LIU, Z.Y., CHEN, Z.G., ZHANG, C. and LI, Y.Q., 2009. Generic object oriented substation event (GOOSE) real-time analysis and surveillance system. Power System Protection and Control, 37(23), pp.92-95.

Zhang, J. and Gunter, C.A., 2010, October. Application-aware secure multicast for power grid communications. In 2010 First IEEE International Conference on Smart Grid Communications (pp. 339-344). IEEE.

Zhao, T., Sevov, L. and Wester, C., 2011, April. Advanced bus transfer and load shedding applications with IEC61850. In 2011 64th Annual Conference for Protective Relay Engineers (pp. 239-245). IEEE.