{"title":"Adaptive frequency containment and balance restoration controls in a distribution network","authors":"E. Rikos, M. Cabiati, C. Tornelli","doi":"10.1109/ISGTEurope.2017.8260269","DOIUrl":"https://doi.org/10.1109/ISGTEurope.2017.8260269","url":null,"abstract":"One of the greatest challenges in the future power systems operation is their ability to host high amounts of Renewable Energy Sources (RES). To cope with this, various research activities such as the ELECTRA Integrated Research Project (IRP) propose solutions that can increase the hosting capacity of power systems. Inside ELECTRA a new control framework has been proposed, the Web-of-Cells (WoC), in which the power system is divided into smaller subsystems (cells) and reorganized in new roles and responsibilities. Each cell has to contribute to balance/frequency and voltage controls and it is responsible for its behavior at its boundaries. In this paper, the results of the analysis that was conducted in the frame of the ELECTRA Researcher Exchange (REX) program are presented about the modelling and simulation of the MV reference grid proposed by CIGRE in combination with two of the control Use Cases (UCs) proposed inside ELECTRA, namely Frequency Containment Control (FCC) and Balance Restoration Control (BRC). The control scheme under study makes use of a novel strategy that adaptively allows the cell controller to detect the location of an imbalance and adjust the primary reserves contribution so that local reserves activations take always priority. Simulation results show that the modelling approach presents good accuracy and overall performance, while the controller implemented shows benefits for the system operation.","PeriodicalId":345050,"journal":{"name":"2017 IEEE PES Innovative Smart Grid Technologies Conference Europe (ISGT-Europe)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116246170","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
P. Grahn, Viktor Briggner, Linus Johansson, D. Babazadeh, L. Nordström
{"title":"Centralized versus distributed state estimation for hybrid AC/HVDC grid","authors":"P. Grahn, Viktor Briggner, Linus Johansson, D. Babazadeh, L. Nordström","doi":"10.1109/ISGTEurope.2017.8260167","DOIUrl":"https://doi.org/10.1109/ISGTEurope.2017.8260167","url":null,"abstract":"The need of transmission grid expansion has drawn the attention towards high voltage DC (HVDC) as a solution. This brings new challenges for power system control application such as state estimation that are originally designed for AC power system. This papers studies centralized and distributed architectures for hybrid AC/HVDC state estimator (SE). Furthermore, the benefit of having bad data detection (BDD) and deploying phasor measurement units (PMU) in the state estimation are investigated. The method used for the SE is the weighted least square (WLS) method. The SE will be developed based on the power grid model ‘The CIGRE B4 DC Grid Test System’. The results of the tests show that the addition of BDD and PMU improved the error of the estimated values. Furthermore the distributed architecture offered slightly less accurate AC values than the centralized.","PeriodicalId":345050,"journal":{"name":"2017 IEEE PES Innovative Smart Grid Technologies Conference Europe (ISGT-Europe)","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125354293","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Linear power-flow models in multiphase distribution networks","authors":"A. Bernstein, E. Dall’Anese","doi":"10.1109/ISGTEurope.2017.8260205","DOIUrl":"https://doi.org/10.1109/ISGTEurope.2017.8260205","url":null,"abstract":"This paper considers multiphase unbalanced distribution systems and develops approximate AC power-flow models wherein voltages, line currents, and powers at the point of common coupling are linearly related to the nodal net power injections. The linearization approach is grounded on a fixed-point interpretation of the AC power-flow equations, and it is applicable to distribution systems featuring a variety of connections for loads and generation units (e.g., wye and ungrounded delta, as well as line-to-line and line-to-grounded-neutral at the secondary of the distribution transformers). The approximate linear models can be naturally leveraged to facilitate the development of computationally-affordable optimization and control applications — from applications for advanced distribution management systems to online and distributed optimization routines. The approximation accuracy of the proposed method is evaluated on different feeders.","PeriodicalId":345050,"journal":{"name":"2017 IEEE PES Innovative Smart Grid Technologies Conference Europe (ISGT-Europe)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130010587","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Electricity consumption contribution to power system inertia — Case electric vehicles and thermostatically controlled loads in Finland","authors":"A. Alahäivälä, M. Lehtonen","doi":"10.1109/ISGTEurope.2017.8260097","DOIUrl":"https://doi.org/10.1109/ISGTEurope.2017.8260097","url":null,"abstract":"Generation of inverter-connected solar and wind power displaces kinetic energy in power systems, decreasing frequency quality and threatening the system security. As a solution, this paper investigates the potential of electricity consumption to increase the inertial response of the system so that the frequency quality is maintained. The study focuses on three types of consumption: Electric vehicle (EV) charging, direct electric space heating (DESH), and the consumption of refrigerators, which all have different characteristics in terms of their response to the power system frequency. We aim to assess their potential inertia contribution in a Finnish case study. Therefore, the study firstly introduces the consumption models with required load control strategies, after which the performance of the loads as a part of the Nordic power system frequency dynamics is simulated. The results indicate that the loads are able to contribute to the system inertia but their consumption may not coincide with the moments of low system kinetic energy.","PeriodicalId":345050,"journal":{"name":"2017 IEEE PES Innovative Smart Grid Technologies Conference Europe (ISGT-Europe)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128434745","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Stochastic market clearing model with probabilistic participation of wind and electric vehicles","authors":"N. Neyestani, F. Soares, J. Iria","doi":"10.1109/ISGTEurope.2017.8260328","DOIUrl":"https://doi.org/10.1109/ISGTEurope.2017.8260328","url":null,"abstract":"In this paper, a mixed-integer linear programing (MILP) model for the stochastic clearing of electricity markets with probabilistic participants is proposed. It is assumed that the sources of uncertainty in the market comes both from generation and demand side. The wind generating unit and electric vehicle aggregator are the supposed sources of uncertainty in the system. For the compensation of probable deviation of stochastic participants, flexible generation and demand will offer for the reserve activation. The two-stage model takes into account the day-ahead cost as well as the expected balancing costs due to probabilistic behavior of uncertain participants. A scenario-based approach is used to model the probabilistic participants. The proposed model stochastically clears the market and the results discuss the lower costs obtained by incorporating various resources of uncertainty and flexibility in the market.","PeriodicalId":345050,"journal":{"name":"2017 IEEE PES Innovative Smart Grid Technologies Conference Europe (ISGT-Europe)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130962283","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Protection scheme for MMC-HVDC DC lines based on boundary current signals","authors":"C. Lv, N. Tai, Xiaodong Zheng, Kaiwen Zha","doi":"10.1109/ISGTEurope.2017.8260231","DOIUrl":"https://doi.org/10.1109/ISGTEurope.2017.8260231","url":null,"abstract":"The application of modular multilevel converter (MMC) is attracting more and more attention in flexible DC systems, particularly with the increasing penetration of distributed generators. The development of MMC-based high voltage DC (MMC-HVDC) technology is constrained by the lack of operational experience and appropriate protection schemes. It is necessary to investigate a reliable protection scheme for MMC-HVDC DC line. In this paper, the difference of boundary current signals under internal faults and external faults is firstly analyzed in detail. A definition is introduced to digitize this difference. Furthermore, based on the difference of boundary current signals, a protection strategy for MMC-HVDC DC lines is proposed. Various simulations are carried out in PSCAD/EMTDC on different fault conditions, such as different fault resistances and distances. It is demonstrated that the proposed scheme is effective and is capable of distinguishing faults quickly and accurately.","PeriodicalId":345050,"journal":{"name":"2017 IEEE PES Innovative Smart Grid Technologies Conference Europe (ISGT-Europe)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129932870","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Methodology for validation of electric power system simulation tools","authors":"A. Suvorov, M. Andreev, N. Ruban, R. Ufa","doi":"10.1109/ISGTEurope.2017.8260101","DOIUrl":"https://doi.org/10.1109/ISGTEurope.2017.8260101","url":null,"abstract":"The analysis results of the existing problem of reliability and validation of widely used digital simulation tools of electric power systems (EPS) are presented in the paper. The reasons of problem are connected with using the numerical integration for stiff nonlinear systems of differential equations high order, describing the processes in real power systems. Fundamental unsolvability of the problem in the framework of numerical approach determines the necessity of obligatory validation of each numerical solution, but it is impossible because the required real measured data is not available for all regimes and processes in EPS. The developed methodology based on hybrid approach is proposed in the paper for validation of simulation tools in all possible regimes and processes (quasi-steady state and transient processes) occurring in modern EPS, including EPS with Smart Grids. The realization principles of the methodology are also considered.","PeriodicalId":345050,"journal":{"name":"2017 IEEE PES Innovative Smart Grid Technologies Conference Europe (ISGT-Europe)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130220382","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A comparison of PI and fuzzy logic control schemes for field oriented permanent magnet synchronous generator wind turbines","authors":"Ahmed S. Al-Toma, G. Taylor, M. Abbod, I. Pisica","doi":"10.1109/ISGTEurope.2017.8260331","DOIUrl":"https://doi.org/10.1109/ISGTEurope.2017.8260331","url":null,"abstract":"Wind turbines require continuous monitoring and control in order to maintain constant power output when the speed of wind changes. Controlling a non-linear model of the wind turbine requires a robust controller that can adjust to the changes in the environment as well as operational conditions. Proportional-Integral (PI) controllers can not cope effectively in cases of sudden change in wind speed or transient operation. For this reason, advanced control schemes have been proposed to mitigate the effects of system disturbance. This paper presents detailed modelling, simulation and analysis of a novel Fuzzy Logic Control (FLC) scheme for variable speed wind turbines using a permanent magnet synchronous generators. The machine side controller is designed to match maximum power extraction from wind with converted power to the DC link side. Detailed strategies for PI control and FLC have been discussed and compared. Simulations for different wind speed profiles are also presented in the paper.","PeriodicalId":345050,"journal":{"name":"2017 IEEE PES Innovative Smart Grid Technologies Conference Europe (ISGT-Europe)","volume":"75 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122351278","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Virtual synchronous machine control with virtual resistor for enhanced short circuit capability","authors":"Christoph Glockler, D. Duckwitz, Friedrich Welck","doi":"10.1109/ISGTEurope.2017.8260278","DOIUrl":"https://doi.org/10.1109/ISGTEurope.2017.8260278","url":null,"abstract":"Increasing shares of power electronic converters in renewable generation challenge power system stability. For very high shares the state of the art current-control approach should be replaced by grid forming control schemes. The virtual synchronous machine (VSM) approach is grid forming and fully compatible to conventional synchronous-machine-based power plants. The high fault currents of synchronous machines are also replicated and lead to excessive current ratings of the semiconductors. Current control could be applied again during faults, however the grid-forming property is lost when it is most needed. We propose a VSM with a virtual resistor that reduces fault currents while the grid forming functionality is maintained. For the most severe fault the peak current amplitude is reduced to 2.5 times the nominal current. Swing mode and high-frequency stability is investigated in detail. The results have been confirmed by experiments. The over-current requirements and thus component cost can be reduced drastically through the application of a virtual resistor. Nonetheless, an increased current rating of the hardware is required to handle severe faults. System studies should be performed to confirm the method on system level.","PeriodicalId":345050,"journal":{"name":"2017 IEEE PES Innovative Smart Grid Technologies Conference Europe (ISGT-Europe)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126574162","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. Balischewski, I. Hauer, M. Wolter, C. Wenge, P. Lombardi, P. Komarnicki
{"title":"Battery storage services that minimize wind farm operating costs: A case study","authors":"S. Balischewski, I. Hauer, M. Wolter, C. Wenge, P. Lombardi, P. Komarnicki","doi":"10.1109/ISGTEurope.2017.8260130","DOIUrl":"https://doi.org/10.1109/ISGTEurope.2017.8260130","url":null,"abstract":"Wind power plants have become a mainstay of German renewable energy production and accounted for 12.3% of gross electricity production in 2015 [1]. Nonetheless, wind turbines do not produce power continuously and require active and reactive power depending on their operating point. Annual energy consumption incurs significant operating costs, which can only be reduced by making technical changes to the existing infrastructure or by modernizing the installed wind turbines. Unlike conventional static power factor compensation systems, battery storage systems (BSS) additionally provide active power and thus double benefits. This paper first describes selected technical constraints of wind farms and defines battery storage system use cases to reduce their operating costs. Furthermore a design algorithm for storage parameters is proposed and the technical configuration is optimized to maximize cost reduction. Experiences and operation data of an 1 MW BSS under test has been factored into use case simulations and results are valued in a cost-benefit-analysis.","PeriodicalId":345050,"journal":{"name":"2017 IEEE PES Innovative Smart Grid Technologies Conference Europe (ISGT-Europe)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126080598","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}