Magnetgärdets transformatorstation är belägen i Ludvika och ägs av Västerbergslagens Energi AB. Transformatorstationen är nyligen ombyggd och nu mer placerad inomhus, vilket gör att påkänningar från väder och vind minskar. För att minimera behovet av personlig tillsyn och öka tillgängligheten behövs dock någon form av tillståndsövervakning. Syftet med examensarbetet har varit att undersöka om det med hjälp av värmekameror är möjligt att tillståndsövervaka de kritiska punkterna i transformatorstationen. För att fastställa detta har teori kring tillståndsövervakning, termografering och värmekameror sammanställts tillsammans med utförda mätningar och tester. Resultaten har sedan diskuterats för att se om ett möjligt lösningsförslag kan presenteras. Viktiga kriterier för att möjligöra tillståndsövervakning med hjälp av värmekameror har tagits fram. Slutsatsen är att det är möjligt, men kräver en komplicerad systemlösning. Lösningsförslaget bygger på flera samspelande delar och bör bli ett kraftfullt övervakningssystem. Huruvida värmekameror är det bästa och enda verktyget är dock tveksamt. Det anses därför väsentligt att även undersöka andra övervakningsmöligheter, som exempel termistorgivare. / The substation called Magnetgärdet is located in Ludvika, Sweden and it is owned by Västerbergslagens Energi AB. The substation has recently been renovated and is now placed indoors, which reduces the influence of weather on the station. To decrease the need for personal supervision and increase the availability of the station a monitoring solution is needed. The purpose of this degree thesis is to examine if it is possible to monitor the condition of critical items in the station with infrared cameras. To determine this, theory on condition monitoring, thermography and thermal imaging cameras has been compiled together with relevant measurements and tests. The results are then discussed to see if a possible solution can be presented. Important criteria for making condition monitoring with infrared cameras possible have also been formulated in this degree thesis. The conclusion is that it is possible, but a complicated system is required. The solution we have given is based on different parts interplaying with each other and it should become a powerful monitoring system. It is however uncertain whether infrared cameras are the only and best tools, therefore other tools should be considered. It might be possible to use thermistors with, or instead of infrared cameras.

Thesis submitted in fulfilment of the requirements for the degree Master of Technology: Electrical Engineering in the Faculty of Engineering at the Cape Peninsula University of Technology 2014 / The IEC 61850 standard, “Communication networks and systems in substations” was promulgated to accommodate the need for a common communication platform within substations for devices from different vendors. The IEC 61850 standard proposes a substation automation architecture that is Ethernet-based, with a “station-bus” for protection devices within the substation and a “process bus” where raw data from the voltage and current transformers are published onto the data network using a device known as a Merging Unit. To date, most of the standardization efforts were focused at the station bus level where event-triggered messages are exchanged between the substation automation devices, commonly referred to as Intelligent Electronic Devices (IEDs). These messages are known as Generic Object Oriented Substation Event messages. Equipment from vendors to accommodate the “process bus” paradigm, however is still limited at present. The Centre for Substation Automation and Energy Management Systems was established within the Electrical Engineering Department at the Cape Peninsula University of Technology with one of its objectives being the development of equipment either for simulation or real-time purposes in compliance with the IEC 61850 standard. In order to fulfil this long-term objective of the Centre, an in-depth understanding of the IEC 61850 standard is required. This document details the efforts at acquiring the requisite knowledge base in support of the educational objectives of the Centre and the research project implements a simulation of a merging unit which is compliant with the functional behavior as stipulated by the standard. This limited functional implementation (i.e. non-real-time) of the merging unit, is achieved through the development of a virtualized data acquisition node capable of synthetic generation of waveforms, encoding of the data and publishing the data in a format compliant with the IEC 61850-9-2 sampled value message structure. This functional behavior of the virtual sensor node which was implemented has been validated against the behavior of a commercial device and the sampled value message structure is validated against the standard. The temporal behavior of the proposed device is commented upon. This research project forms the basis for future real-time implementation of a merging unit.

With the advancements in the Industrial Internet of Things (IIoT), new networking requirements and demands are introduced to Substation Automation Systems (SAS) within electrical power grids. The possibility of merging Information Technology (IT) and Operational Technology (OT) traffic on the same network to achieve higher productivity, however, presents new challenges in providing real-time guarantees to OT traffic. Time-Sensitive Networking (TSN) can be a promising solution that allows IT and OT traffic to coexist seamlessly while still providing real-time guarantees for critical applications. Substations act as critical nodes within power grids, and their digitalisation is a crucial element in the energy transition. A digital substation handles International Electrotechnical Commission (IEC) 61850 protocol traffic such as Generic Object Oriented Substation Event (GOOSE), Sampled Values (SV), and Manufacturing Message Specification (MMS), which all have strict timing requirements. The integration of TSN into these substations could improve the handling of this traffic and, consequently, the controllability of power grids. This thesis investigates the use of TSN in an IEC 61850 process bus, typically implemented in an SAS. A series of simulated test scenarios were developed to evaluate the impact of TSN compared to traditional networking methods. These included configurations using Ethernet, Ethernet with priority queuing, and TSN with Time-Aware Shaper (TAS) and Credit-Based Shaper (CBS). The results indicate that TSN can meet critical timing requirements, reduce jitter, and manage sporadic traffic effectively under high traffic loads. While the TAS scheduler may increase End-to-End delay for periodic traffic, CBS can reduce it for event-based traffic. Furthermore, robust timing guarantees are ensured for the TSN scenarios by providing a feasible schedule for Scheduled Traffic (ST) and a worst-case response time analysis for Audio-Video Bridging (AVB) traffic. This research highlights TSN’s potential to improve grid controllability and reliability through enhanced network performance, illustrating its role in the future of resilient grid technologies.

Power system fault detection is conventionally achieved using current and potential measurements. An alternate and unconventional form of protective relaying is feasible using rigid bus conductor motion as the means of detection. The research presented focuses on the detection of power system faults using visual displacement of conductor spans. Substation rigid bus conductor motion is modeled using dual spring-mass systems for accurate representation of conductor response to electromagnetic forces generated during system faults. Bundled rigid conductors have advantages including detection independent of system load currents and improved ability to detect polyphase and single phase faults. The dynamic motion of the conductors during the fault is optically monitored with a laser detection system. Timeovercurrent characteristics are derived for the application of fault detection. The response time of the conductor detector system is slower than conventional relays due to the natural frequencies of the conductor span limiting the speed of its displacement. This response time makes the fault detection system using conductor displacement an ideal candidate for a backup relay in power system protection schemes.

O trabalho apresenta o protótipo de um conjunto de sistemas especialistas para o auxílio na operação, monitoração e a avaliação do desempenho da manutenção de uma subestação de energia. Os sistemas especialistas propostos têm como objetivos básicos: o tratamento de alarmes da subestação, para depuração e triagem dos mesmos durante perturbações facilitando a análise e ações do operador; a localização de defeitos através da iteração entre alarmes gerados (fatos), regras que relacionam alarmes a causas (base de conhecimento) e a estrutura que relaciona este conjunto de regras (máquina de inferência); a reconfiguração da subestação para transferência de cargas entre circuitos através de um conjunto de manobras gerados por algoritmos de busca e de regras ligadas aos limites das grandezas elétricas dos equipamentos da rede; e ainda a análise do desempenho da manutenção baseada no conceito de índice de mérito operativo aplicado a subestações. O protótipo prevê o desenvolvimento utilizando a linguagem PROLOG, que é voltada para o tratamento declarativo de informações. Foram utilizados dados de uma subestação de uma empresa concessionária de energia para que se pudesse avaliar melhor o desenvolvimento das bases de conhecimento e da própria arquitetura do conjunto e de sua comunicação. Os testes efetuados mostraram resultados promissores e com grau de acerto elevado, o que indica que o sistema desenvolvido, é um embrião confiável para maiores sofisticações. O trabalho termina por apresentar estas novas possibilidades de aperfeiçoamento do sistema. / This work presents a set of expert systems for operation , supervision and maintenance of a electrical energy substation. The function performed by the expert systems presented here are: alarm processing, fault diagnosis, reconfiguration and the analysis of the maintenance performance. The system was developed in PROLOG language. Substation characteristics, data and information has been provided by a São Paulo utility company. The knowledge basis for the expert systems was developed with basis in such information. Tests were carried out to verify this system performance including the architecture and communication. The results are very promising and with a high level of confidence, which means that this system can be used as a seed for future improvement. The work ends by suggesting such improvements and new applications.

O trabalho apresenta o protótipo de um conjunto de sistemas especialistas para o auxílio na operação, monitoração e a avaliação do desempenho da manutenção de uma subestação de energia. Os sistemas especialistas propostos têm como objetivos básicos: o tratamento de alarmes da subestação, para depuração e triagem dos mesmos durante perturbações facilitando a análise e ações do operador; a localização de defeitos através da iteração entre alarmes gerados (fatos), regras que relacionam alarmes a causas (base de conhecimento) e a estrutura que relaciona este conjunto de regras (máquina de inferência); a reconfiguração da subestação para transferência de cargas entre circuitos através de um conjunto de manobras gerados por algoritmos de busca e de regras ligadas aos limites das grandezas elétricas dos equipamentos da rede; e ainda a análise do desempenho da manutenção baseada no conceito de índice de mérito operativo aplicado a subestações. O protótipo prevê o desenvolvimento utilizando a linguagem PROLOG, que é voltada para o tratamento declarativo de informações. Foram utilizados dados de uma subestação de uma empresa concessionária de energia para que se pudesse avaliar melhor o desenvolvimento das bases de conhecimento e da própria arquitetura do conjunto e de sua comunicação. Os testes efetuados mostraram resultados promissores e com grau de acerto elevado, o que indica que o sistema desenvolvido, é um embrião confiável para maiores sofisticações. O trabalho termina por apresentar estas novas possibilidades de aperfeiçoamento do sistema. / This work presents a set of expert systems for operation , supervision and maintenance of a electrical energy substation. The function performed by the expert systems presented here are: alarm processing, fault diagnosis, reconfiguration and the analysis of the maintenance performance. The system was developed in PROLOG language. Substation characteristics, data and information has been provided by a São Paulo utility company. The knowledge basis for the expert systems was developed with basis in such information. Tests were carried out to verify this system performance including the architecture and communication. The results are very promising and with a high level of confidence, which means that this system can be used as a seed for future improvement. The work ends by suggesting such improvements and new applications.

A utilização de energia solar fotovoltaica é amplamente difundida no mundo e possui caráter promissor no Brasil atualmente. Apesar do grande potencial brasileiro, esta fonte de energia ainda apresenta baixos níveis de utilização. A competitividade da geração fotovoltaica de grande porte em usinas solares fotovoltaicas ainda não atingiu patamares admissíveis com taxas de retorno financeiro atrativas ao mercado nacional. Por se tratar de uma fonte de energia renovável, sua utilização no cenário mundial tem apresentado crescimento nos últimos anos. Mesmo em países que apresentam potenciais solares inferiores aos do Brasil, esta fonte de energia tem se mostrado competitiva devido aos incentivos oferecidos. Tendo em vista este prisma, o presente trabalho busca apresentar possibilidades de inserção de usinas solares fotovoltaicas no Estado do Rio Grande do Sul. A usina proposta possui capacidade de geração de 30 MWp. Este estudo visa apresentar uma proposta de diversificar a geração de energia elétrica no estado do Rio Grande do Sul, apresentando uma nova alternativa de geração de energia renovável. Para tal realização, foram estudadas as linhas de transmissão e subestações existentes no estado do Rio Grande do Sul como forma de avaliar a possibilidade de conexão direta da nova usina, tendo como objetivo a redução do custo de instalação. Foi realizado o cálculo da produtividade fotovoltaica para o estado do Rio Grande do Sul e a análise dos custos de instalação desta fonte no Estado, bem como a relação de preço da geração centralizada no estado. / The use of photovoltaic solar energy is widespread in the world and has promising character in Brazil today. Despite the large Brazilian potential, this energy source still shows low levels of utilization. The competitiveness of photovoltaic generation in large solar photovoltaic power plants has not yet reached acceptable levels with attractive rates of financial return to the national market. Because it is a renewable source of energy, its use in the world has been increasing in recent years. Even in countries that have lower solar potential than Brazil, this source of energy has been competitive due to the incentives offered. Given this perspective, this paper seeks to show the possibilities for integration of photovoltaic solar plants in the state of Rio Grande do Sul. The proposed plant has a generation capacity of 30 MWp . This study aims to present a proposal to diversify the electricity generation in the state of Rio Grande do Sul, presenting a new alternative source of renewable energy . For this achievement, the existing transmission lines and substations were studied in the state of Rio Grande do Sul as a way to evaluate the possibility of direct connection of the new plant, with the objective of reducing the cost of installation. The calculation of photovoltaic productivity for the state of Rio Grande do Sul and cost analysis of installing this source was held as well the price ratio of centralized generation.

With increased load demands from the customers, substation congestion problems have become inevitable to the utility companies. Instead of expanding related system installations to alleviate the short-term overloads on the facilities, feasibilities of integrating distributed generator (DG) units to defer the possible congestions are of much concern. This thesis presents an optimal location and reliability analyzing scheme for distribution system integrated with DG units, and provides the systematic guidance to utility companies for related operations. The methodology focuses on the substation capacity constraints and provides the optimal DG locations that can alleviate the congestion problem with highest reliability indices. The proposed analyzing scheme can supply valuable assistance to the utility companies and small independent power producers (IPP) for determining the installations and integrations of DG units to defer possible emerging substation expansions.

The modern society uses more and more electronic devices needed to being able to function together. This put higher demands on the electrical grid together with that the typical load have changed from the past. Therefore utility companies are obliged to keep the voltage within certain limits for this to function. What exact these limits have been have not always been clear since they have not been gathered in one single document.  This thesis is a cooperation with Kraftringen who also has been the initiator. Kraftringen would like to become more proactive in their work regarding electric power quality. For becoming more proactive continuously measurements have to be done but the locations have to be carefully selected in the beginning to get a wider perspective of the grid. Energy markets inspectorate (EI) is supervisory of the electric power quality in Sweden and since 2011 they have published a code of statutes (EIFS 2011:2 later 2013:1) intended to summarize limits on voltage. Some of the electrical power quality aspects are not mentioned in EIFS 2013:1 and standards have to be used to find limited values. Flicker and interharmonics are not mentioned in EIFS 2013:1 and for values on flicker the standard SS-EN 50160 has to be used and for interharmonics the standard SS-EN 61000-2-2 state limit values. Besides all this there are standards with stricter limits than EIFS 2013:1 e.g. for total harmonic distortion on voltage were SS-EN 61000-2-2 suggest 6 % instead of 8 %. Three different field studies have been conducted in order to get some perception of the present situation regarding electric power quality. Two measurements were conducted on a typical office building because they represents a large part of the typical load in Lund. The third measurement was conducted on a substation in a rural area to get a perception of the situation outside urban areas.  These measurements shown that the overall electric power quality was within given limits according to EIFS 2013:1 and different standards. However, conducted measurements shown some interesting results. Both the typical office buildings have a slightly capacitive power factor which results in that the voltage inside the building is going to be slightly higher than at the substation. Since the voltage level at the measured urban substation was above nominal voltage level with about 2-5 % this could be problematic. Another eventual problem with a load with a capacitive power factor is resonance with the inductive parts of the grid like transformers leading to magnified harmonic levels. It is suggested that Kraftringen expand their number of permanent electric power quality measurement locations to get a better overview of the present situation. The best suited locations to start with are such that have received complaints earlier, preferably measured on the low voltage side of the transformer for also register the amount of zero sequence harmonics. Next step in the measurement expansion would be substations known to be under higher load than others or substations with a PEN-conductor in a smaller area than the phase conductors, supplying a typical office load with high amounts of third harmonics and unbalance. From this it would be appropriate to spread out the measurement locations geographically to better get to know the grids behaviour.

This dissertation presents a comprehensive and integrated design methodology to optimize both the electrical and the economic performance of a utility power distribution system. The proposal is structured to facilitate its adoption and incorporation into the existing utility infrastructure by allowing the various portions of the new design to be implemented gradually into the existing infrastructure without the need to abandon the portions of the existing system that are performing satisfactorily. The topology of the substation plays a vital role in determining both the reliability and the economy of the distribution system. The ring bus topology is offered as the best topology design, and its characteristics as seen at the distribution level are examined. A key concept presented in this dissertation is that the distribution system must be optimized as a whole, not subsystem by subsystem. Optimizing the substation and the primary feeder system separately does not assure an optimal system; in fact, independent design of the two subsystems is likely to produce a non-optimal system laden with operational problems. An integrated approach is essential to assure optimum performance, and the integration process requires an iterative approach. This iterative approach is presented using an example. Innovative changes to the protection strategy of the feeder system can greatly enhance the reliability of the distribution system. The use of communication-based overcurrent detection is presented. This transmission-like scheme, when applied at the distribution level, improves both the reliability and the economy of the system substantially over traditional time-coordinated overcurrent protection philosophies. An application of these proposed innovations leads to the design of a hypothetical system, which is in turn analyzed from both electrical and economic perspectives.