Research on grid challenges and smart grid development: the case of Sichuan grid

As the most important driving force of modern social development and a significant symbol of modern civilization, electric power is in booming demand. Furthermore, electric power is a complex system which integrates power generation, power transmission, power distribution and power utilization together and achieves generation, transmission, distribution and utilization instantaneously at the same time. It notably features with network industry and network economy. Power grid is a hub which links electricity production and electricity consumption in the power system. On the basis of basic theories of network industry and network economy, this thesis discusses the development of smart grid from the aspects of “network challenges”, resources and energy challenges and new energy access challenges encountered and counter-measures in the development of modern grid. Based on the development environment of China power, especially the Sichuan power grid, and spatial mismatching of power supply and demand (including new energy resources and distribution), this thesis analyzes and explains China (Sichuan) smart grid is strong smart grid which has UHV power grid as the backbone frame, and features information technology, and automation.Devido ao facto de ser uma força impulsionadora do desenvolvimento económico e um simbolo muito importante da civilização moderna, a procura de electricidade tem aumentado consideravelmente nas últimas décadas. Contudo, a energia elétrica é um sistema complexo que integra geração, transmissão, distribuição e implica que a oferta e a procura sejam simultâneas. A indústria da electricidade tem muitas características da economia em rede. A rede elétrica deve ser vista como um “hub” que liga a produção de electricidade ao seu consumo. Tendo por base, as teorias da indústria em rede e da economia em rede, esta tese discute o desenvolvimento das redes elétricas segundo as perspectivas dos “desafios que se colocam às redes”, dos desafios em termos de recursos e dos desafios que se colocam ao desenvolvimento da rede elétrica moderna. Esta tese estuda de uma forma detalhada os problemas relacionados com a construção de uma rede elétrica inteligente na província de Sichuan, China

Distribution Automation Laboratory Assignments for Students in Tampere University of Technology

Distribution automation is a fundamental part of distribution network operation. In Finland, the goal is to increase the number of automated functions in a distribution network, because of the constantly tightening requirements for decreasing the duration of outages. For students, who study power engineering, it is beneficial to understand the possibilities of distribution automation. In Tampere University of Technology, the course Distribution Automation ensures the understanding of the fundamentals of distribution automation and network operation for students. The course includes lecture subjects, written exercises and laboratory assignments. The main objective of this thesis is to improve and update laboratory environments of distribution automation for the course Distribution Automation. The laboratory environments should help students understand distribution network protection, the role of DMS and SCADA system, and smart metering. This thesis examines previous laboratory implementations on the course and distribution automation in general. The laboratory environments and students’ feedback from previous laboratory implementations are presented in this thesis. The chapter on distribution automation displays information about distribution network protection, SCADA and DMS systems, AMI system and protocols. The distribution network protection section presents basic needs and regulations for distribution network protection. SCADA and DMS section introduces functionalities of these systems whereas smart metering section describes AMI system naming and structure. Protocols and standards section describes IEC 104, IEC 61850, OPC, DLMS/COSEM, object oriented information models and OSI model communication structures. As a result of this thesis, implementations from two different laboratory environments are introduced. The first laboratory implementation includes distribution network protection and IEDs. The second laboratory implementation includes a smart meter, DMS and SCADA systems, and remote communication between the control center, the substation and the smart meter

Smart grid replication : handbook for India

India has embarked on an ambitious sustainable development pathway by applying a multipronged approach spanning several sectors from developing smart cities to enabling electric vehicles. In the power sector, it is necessary to transform and prepare the grid at both the transmission and distribution levels to ensure the success of India’s sustainability journey. Implementation of innovative smart grid projects will enable India to reach its ambitious sustainability goals. However, a multitude of challenges in rolling out these novel solutions on a nationwide scale continue to persist. The handbook contains insights and tools that will aid implementation and replication of innovative smart grid projects in India. Therefore, this handbook provides its readers with the following: Insights into opportunities and barriers in replicating smart grid projects in India; A framework for selecting use cases based on their relevance to India; The CBA tool to assess the costs and benefits of smart grid use cases in India; The SRA tool to assess the scalability and replicability of smart grid use cases in India; Insights from applying the abovementioned tools to both European and Indian case studies

Data Acquisition Applications

Data acquisition systems have numerous applications. This book has a total of 13 chapters and is divided into three sections: Industrial applications, Medical applications and Scientific experiments. The chapters are written by experts from around the world, while the targeted audience for this book includes professionals who are designers or researchers in the field of data acquisition systems. Faculty members and graduate students could also benefit from the book

Development of a decision support system through modelling of critical infrastructure interdependencies : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Emergency Management at Massey University, Wellington, New Zealand

Critical Infrastructure (CI) networks provide functional services to support the wellbeing of a community. Although it is possible to obtain detailed information about individual CI and their components, the interdependencies between different CI networks are often implicit, hidden or not well understood by experts. In the event of a hazard, failures of one or more CI networks and their components can disrupt the functionality and consequently affect the supply of services. Understanding the extent of disruption and quantification of the resulting consequences is important to assist various stakeholders' decision-making processes to complete their tasks successfully. A comprehensive review of the literature shows that a Decision Support System (DSS) integrated with appropriate modelling and simulation techniques is a useful tool for CI network providers and relevant emergency management personnel to understand the network recovery process of a region following a hazard event. However, the majority of existing DSSs focus on risk assessment or stakeholders' involvement without addressing the overall CI interdependency modelling process. Furthermore, these DSSs are primarily developed for data visualization or CI representation but not specifically to help decision-makers by providing them with a variety of customizable decision options that are practically viable. To address these limitations, a Knowledge-centred Decision Support System (KCDSS) has been developed in this study with the following aims: 1) To develop a computer-based DSS using efficient CI network recovery modelling algorithms, 2) To create a knowledge-base of various recovery options relevant to specific CI damage scenarios so that the decision-makers can test and verify several ‘what-if’ scenarios using a variety of control variables, and 3) To bridge the gap between hazard and socio-economic modelling tools through a multidisciplinary and integrated natural hazard impact assessment. Driven by the design science research strategy, this study proposes an integrated impact assessment framework using an iterative design process as its first research outcome. This framework has been developed as a conceptual artefact using a topology network-based approach by adopting the shortest path tree method. The second research outcome, a computer-based KCDSS, provides a convenient and efficient platform for enhanced decision making through a knowledge-base consisting of real-life recovery strategies. These strategies have been identified from the respective decision-makers of the CI network providers through the Critical Decision Method (CDM), a Cognitive Task Analysis (CTA) method for requirement elicitation. The capabilities of the KCDSS are demonstrated through electricity, potable water, and road networks in the Wellington region of Aotearoa New Zealand. The network performance has been analysed independently and with interdependencies to generate outage of services spatially and temporally. The outcomes of this study provide a range of theoretical and practical contributions. Firstly, the topology network-based analysis of CI interdependencies will allow a group of users to build different models, make and test assumptions, and try out different damage scenarios for CI network components. Secondly, the step-by-step process of knowledge elicitation, knowledge representation and knowledge modelling of CI network recovery tasks will provide a guideline for improved interactions between researchers and decision-makers in this field. Thirdly, the KCDSS can be used to test the variations in outage and restoration time estimates of CI networks due to the potential uncertainty related to the damage modelling of CI network components. The outcomes of this study also have significant practical implications by utilizing the KCDSS as an interface to integrate and add additional capabilities to the hazard and socio-economic modelling tools. Finally, the variety of ‘what-if’ scenarios embedded in the KCDSS would allow the CI network providers to identify vulnerabilities in their networks and to examine various post-disaster recovery options for CI reinstatement projects

Novel Methods for Loss of Mains Protection

Small-scale generation connected to distribution networks has increased significantly in recent years. This trend is driven by developments in distributed generation (DG) technologies, environmental concerns and economic reasons. The diffusion of generation into the distribution network level has many potential benefits, but it also raises challenges, such as unintentional islanding, which is hazardous to the safety of both personnel and equipment. Due to the safety risks, all DG units need to be equipped with a loss of mains (LOM) protection scheme capable of rapidly detecting and stopping islanding. LOM protection methods can be divided into passive, active and communication-based methods. Passive methods rely on detecting islanding by monitoring chosen system quantities. These methods are affordable and applicable to all types of DG units, but their performance is highly dependent on the local power imbalances between the production and consumption in the islanded zone. Most, if not all, passive methods, fail to detect islanding if the local production closely matches the local consumption. The set of power imbalance combinations that lead to non-detected islanding is referred to as the non-detection zone (NDZ). Active methods are based on deliberately injecting small perturbations to the grid and monitoring the response of the system. These methods generally have smaller NDZ than passive methods. However, this comes at the cost of degraded power quality. Communication-based methods rely on other means than the local monitoring of system quantities, which makes them immune to the NDZ problem. However, these methods tend to be costly.The performance of passive and active methods can be improved by applying more sensitive LOM protection settings. However, if the LOM protection settings are too sensitive, voltage dips caused by faults in the transmission grid may result in a cascading disconnection of DG. In order to avoid such risks, which threaten the system’s stability, many grid codes include fault-ridethrough (FRT) requirements, which specify the depth and duration of voltage dips which DG units need to be able to withstand. FRT requirements often also require the DG units to feed reactive current to the grid during the voltage dip in order to support the system voltages. The work conducted for this thesis indicates that FRT requirements significantly degrade the performance of LOM protection. This thesis also studies how the type of the protected DG unit affects LOM protection. The frequency of an islanded circuit sustained by a directly-coupled synchronous generator is determined by the local active power imbalance, whereas the frequency of an islanded circuit sustained by a converter-coupled DG unit is determined by the local reactive power imbalance. However, when there are both directly-coupled synchronous generators and convertercoupled DG units in an islanded circuit, the synchronous generator seems to dominate these relationships. This has significant implications on the performance of active LOM protection schemes.One of the main issues distribution system operators face when they are evaluating the adequacy of LOM protection for DG installations is the lack of suitable analysis tools. This thesis proposes a novel LOM risk management procedure which utilizes the existing analysis tools embedded in a modern network information system (NIS). This NIS-based procedure analyzes what kind of power imbalance combinations are possible in the studied network sections. Based on the possible combinations of power imbalances and predefined NDZ mappings of optional LOM protection schemes, the procedure tells protection engineers if there are any risks of non-detected islanding in the analyzed network sections and proposes which LOM protection schemes would be most suitable for each DG installation. Although the proposed LOM risk management tool is presented at the concept level only here, it is clearly a promising area for future research.Two active LOM protection methods and one communication-based protection automation concept were also developed during this thesis work. The first of the active LOM protection methods is based on forcing the frequency of an islanded circuit out of the utilized frequency thresholds by constant injection of reactive power pulses and a dedicated reactive power versus frequency droop. The knowledge gained during the development of this method resulted in a second, significantly more advanced, active LOM protection scheme. This is based on forcing the rate-ofchange-of-frequency of an islanded circuit to a desired value by applying a dedicated reactive power versus frequency droop. This method is able to detect islanding rapidly and reliably even if the local power imbalances are negligible. Moreover, this can be achieved with a very modest injection of reactive power. The communication-based protection automation concept is designed to solve typical DG related protection challenges and to automatically change the feeding path of the protected DG unit in case if the original feeding route becomes faulted. However, the successfulness of the automatic feeding path changing depends on many factors such as DG unit type, network parameters and the momentary input power provided by the primary energy source.The methods developed in this thesis have slightly different purposes. The proposed NIS-based LOM risk assessment procedure is useful for evaluating the adequacy of existing LOM protection as well as for choosing optimal LOM protection schemes for new DG installations. If the LOM risk assessment procedure indicates that the local power imbalances will always be very large, then passive LOM protection schemes are a sensible choice. However, should the LOM risk assessment procedure reveal that the local power imbalances could be so small that reliable LOM protection cannot be ensured with passive LOM protection schemes, then active or communication-based LOM protection schemes are preferable. Active LOM protection schemes are suitable if the ratio of converter-coupled to directly-coupled generator capacity in the analyzed zone is large. This is because certain active LOM schemes, such as the one proposed in this thesis, are able to detect islanding reliably and rapidly even if the local active- and reactive power imbalances would be negligible, provided that the ratio between converter coupled to directly coupled synchronous generator capacity is large. However, if a significant proportion of the generation capacity in the analyzed network section is synchronous generator based, then sensitive and rapid LOM protection cannot always be guaranteed. In such cases, it is advisable to utilize advanced communication-based LOM protection schemes which are immune to the NDZ problem

Power Quality

Electrical power is becoming one of the most dominant factors in our society. Power generation, transmission, distribution and usage are undergoing signifi cant changes that will aff ect the electrical quality and performance needs of our 21st century industry. One major aspect of electrical power is its quality and stability – or so called Power Quality. The view on Power Quality did change over the past few years. It seems that Power Quality is becoming a more important term in the academic world dealing with electrical power, and it is becoming more visible in all areas of commerce and industry, because of the ever increasing industry automation using sensitive electrical equipment on one hand and due to the dramatic change of our global electrical infrastructure on the other. For the past century, grid stability was maintained with a limited amount of major generators that have a large amount of rotational inertia. And the rate of change of phase angle is slow. Unfortunately, this does not work anymore with renewable energy sources adding their share to the grid like wind turbines or PV modules. Although the basic idea to use renewable energies is great and will be our path into the next century, it comes with a curse for the power grid as power fl ow stability will suff er. It is not only the source side that is about to change. We have also seen signifi cant changes on the load side as well. Industry is using machines and electrical products such as AC drives or PLCs that are sensitive to the slightest change of power quality, and we at home use more and more electrical products with switching power supplies or starting to plug in our electric cars to charge batt eries. In addition, many of us have begun installing our own distributed generation systems on our rooft ops using the latest solar panels. So we did look for a way to address this severe impact on our distribution network. To match supply and demand, we are about to create a new, intelligent and self-healing electric power infrastructure. The Smart Grid. The basic idea is to maintain the necessary balance between generators and loads on a grid. In other words, to make sure we have a good grid balance at all times. But the key question that you should ask yourself is: Does it also improve Power Quality? Probably not! Further on, the way how Power Quality is measured is going to be changed. Traditionally, each country had its own Power Quality standards and defi ned its own power quality instrument requirements. But more and more international harmonization efforts can be seen. Such as IEC 61000-4-30, which is an excellent standard that ensures that all compliant power quality instruments, regardless of manufacturer, will produce of measurement instruments so that they can also be used in volume applications and even directly embedded into sensitive loads. But work still has to be done. We still use Power Quality standards that have been writt en decades ago and don’t match today’s technology any more, such as fl icker standards that use parameters that have been defi ned by the behavior of 60-watt incandescent light bulbs, which are becoming extinct. Almost all experts are in agreement - although we will see an improvement in metering and control of the power fl ow, Power Quality will suff er. This book will give an overview of how power quality might impact our lives today and tomorrow, introduce new ways to monitor power quality and inform us about interesting possibilities to mitigate power quality problems. Regardless of any enhancements of the power grid, “Power Quality is just compatibility” like my good old friend and teacher Alex McEachern used to say. Power Quality will always remain an economic compromise between supply and load. The power available on the grid must be suffi ciently clean for the loads to operate correctly, and the loads must be suffi ciently strong to tolerate normal disturbances on the grid

Local Energy Markets - Simulative Evaluation and Field Test Application of Energy Markets on Distribution Grid Level

Widespread introduction of Distributed Energy Resources (DERs) such as volatile renewable generation, electric vehicles, heat-pumps and battery storages causes a paradigm shift of the power system. Traditional power systems with few large-scale power plants are expanded or replaced by millions of small- to medium-size DERs. Local Energy Markets (LEMs) are a promising approach to facilitate the optimal operation and dispatch of DERs and enhance grid-integration on regional grid levels. In this Thesis, a novel linear-optimization-based market model for LEMs is developed. The market matching problem aims to maximize the social welfare of participants while considering technical and financial aspects of participants’ assets and the distribution grid. A simulative framework is set-up to evaluate the model with regards to its capabilities to foster the optimal use of flexibilities, to provide sufficient financial incentives for participants and to improve grid-integration. Yearly simulations of LEMs and a benchmark case are carried out for three different grid types (rural, semiurban, urban) and scenario years ranging from 2020 until 2035 in 5 year steps. The simulation results reveal that self-consumption and self-sufficiency of the local energy system can be increased by 4 ... 23 and 1 ... 9 percentage points depending on the grid type when compared to a business as usual benchmark case. An analysis of possible designs for regulated electricity price components in LEMs shows that a reduction of feed-in and load peaks of 30 ... 64 % can be achieved when considering power fees in the market matching problem. The simulative evaluation also shows that the market model is able to generate temporal, spatial, and asset-specific prices signals. Depending on the grid type and its load-generation ratio, participants with generation assets have higher benefits in urban, load-dominated grids whereas consumers have higher benefits in generation-dominated rural and semiurban grids. Load forecast uncertainty is identified as one of the major challenges in LEMs. Compared to simulations with perfect foresight, benefits of market participants are substantially decreased taking into account typical electric load forecast errors on the level of individual households. The application of the market model in a six months field-test in Southern Germany demonstrates the real world applicability of the developed approach. The field-test confirms findings from the simulative evaluation regarding the implication of forecast errors and generated price signals. It additionally shows that market interfaces to the Distribution System Operator (DSO) might further increase grid-integration capabilities of LEMs. By taking into account active power constraints of the DSO, 1499 events of critical grid load could be avoided

Teollisuuden palveluyrityksen pysyvä kilpailuetu

Over the last 20 years, Finland’s industrial service business – specifically its electrical and telecom network services and industrial services – has undergone a remarkable transformation. Network owners have outsourced these functions to newly established service companies, and a remarkable new service industry has resulted. After undergoing a rapid growth phase, it has faced numerous challenges, such as decreasing volumes and profitability, as well as new competitors. However, this service business transformation has not yet been the subject of theoretical nor practical research. This thesis examines this transformation from the perspective of service companies and their customers. The research questions are as follows: How can a sustainable competitive advantage for industrial service businesses be created? Do conflicts between service providers’ and customers’ targets exist? Can a win–win position be found? The research utilized theoretical approaches that were based primarily on deductive theory development, qualitative and quantitative methodologies, and a cross-sectional time horizon. The theoretical aspect of the research related to firm strategies, models of competitive and sustainable competitive advantage, conceptual frameworks, and methods and tools, all of which are applicable to the achievement of a sustainable advantage. The information was collected via questionnaires, in-depth interviews, and public reports. Based on the results, customers were very satisfied with service outsourcing and the larger service packages to come. However, service company volumes and profitability decreased, marginal business and competence development methods and investments were applied, and there was no service differentiation between competitors. Conflicts between service providers’ and customers’ competitive advantage targets were marginal and related solely to financials. A sustainable competitive advantage business model called ‘Smart Service’ was developed, and it comprises four sub-processes: profitability/growth, market analysis/customer proximity, critical competence/ resource, and service business development plans. The researched industrial service companies need to employ these new business approaches to recover their sustainable and profitable service business.Sähkö- ja televerkkojen sekä teollisuuden kunnossapitopalvelujen rakenne on muuttunut merkittävästi viimeisen 20 vuoden aikana Suomessa. Verkkoyhtiöt ovat ulkoistaneet näitä palveluliiketoimintoja uusille perustetuille palveluyhtiöille. Uusi merkittävä palvelutoimiala on syntynyt. Nopean kasvujakson jälkeen palveluyhtiöt ovat kohdanneet monia haasteita kuten liikevaihdon ja kannattavuuden laskemisen sekä uusien kilpailijoiden tulon markkinoille. Tämä väitöskirja tutkii tätä liiketoimintamuutosta sekä palveluyhtiöiden että niiden asiakkaiden näkökulmasta. Tutkimuskysymykset ovat: miten kehittää palveluyritysten pysyvä kilpailuetu; ovatko palveluyhtiöiden ja niiden asiakkaiden tavoitteet ristiriidassa keskenään ja voidaanko yhteinen win-win asetelma luoda? Väitöskirja rakentuu teoreettiseen deduktiiviseen viitekehitykseen, kvantitatiiviseen ja kvalitatiiviseen analyysiin sekä poikittaistutkimusmenetelmään. Teoriaosa koostuu yritysstrategiaosuudesta, yrityksen johtamisteoria osasta, kilpailuetu- ja pysyvän kilpailuedun malleista sekä pysyvän kilpailuedun menetelmistä ja työkaluista. Lähtötietojen keruussa käytettiin kyselyjä, syvähaastatteluja sekä julkisia yritysten tietolähteitä. Tutkimustyön päätulokset olivat: asiakkaat olivat erittäin tyytyväisiä palveluliiketoimintojen ulkoistukseen ja jatkossa isompia palvelukokonaisuuksia siirtyy palveluyrityksille. Palveluyritysten liikevaihdot ja kannattavuudet ovat laskeneet, liiketoimintojen ja osaamisen kehittämiseen ei panosteta juuri ollenkaan eikä erottautumista palveluissa kilpailijoiden kesken ole tapahtunut. Palveluyhtiöiden ja niiden asiakkaiden tavoitteissa ei ole juurikaan eroavaisuuksia, taloustavoitteissa luonnollisesti jonkun verran. Väitöskirjassa kehitettiin pysyvän kilpailuedun liiketointamalli, joka pohjautuu tutkittuun teoreettiseen ja konseptuaaliseen viitekehykseen ja työkaluihin sekä tutkimuksen empiirisiin tuloksiin. Liiketoimintamalli sai nimen ’Älykäs palvelu -työkalu’. Se koostuu neljästä osaprosessista: Kannattavuus/Kasvu, Markkina-analyysi/Asiakasläheisyys, Kriittiset Osaamiset/Resurssit ja Palvelujen Kehittämissuunnitelmat. Tutkittu palveluliiketoiminta selkeästi tarvitsee uutta liiketoimintamallia parantaakseen pysyvää kilpailukykyä ja kannattavuutta.fi=vertaisarvioitu|en=peerReviewed