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Content available Multi-sourced power system restoration strategy based on modified Prim’s algorithm
100%
Łukaszewski A. , Nogal Ł.
Bulletin of the Polish Academy of Sciences. Technical Sciences
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2021
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tom Vol. 69, nr 5
art. no. e137942
EN
Self-healing grids are one of the most developing concepts applied in electrical engineering. Each restoration strategy requires advanced algorithms responsible for the creation of local power systems. Multi-agent automation solutions dedicated for smart grids are mostly based on Prim’s algorithm. Graph theory in that field also leaves many problems unsolved. This paper is focused on a variation of Prim’s algorithm utility for a multi-sourced power system topology. The logic described in the paper is a novel concept combined with a proposal of a multi-parametrized weight calculation formula representing transmission features of energy delivered to loads present in a considered grid. The weight is expressed as the combination of three elements: real power, reactive power, and real power losses. The proposal of a novel algorithm was verified in a simulation model of a power system. The new restoration logic was compared with the proposal of the strategy presented in other recently published articles. The novel concept of restoration strategy dedicated to multi-sourced power systems was verified positively by simulations. The proposed solution proved its usefulness and applicability.
2
Content available Influence of lightning current surge shape and peak value on grounding parameters
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Łukaszewski A. , Nogal Ł.
Bulletin of the Polish Academy of Sciences. Technical Sciences
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2021
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tom Vol. 69, nr 2
art. no. e136730
EN
Groundings are necessary parts included in lightning and shock protection. In the case of a surge current, high current phenomena are observed inside the grounding. They are result of the electrical discharges around the electrode when the critical field is exceeded in a soil. An available mathematical model of grounding was used to conduct computer simulations and to evaluate the influence of current peak value on horizontal grounding parameters in two cases. In the first simulations, electrode placed in two different soils were considered. The second case was a test of the influence of current peak value on grounding electrodes of various lengths. Simulation results show that as soil resistivity increases in value, the surge impedance to static resistance ratio decreases. In the case of grounding electrodes lengths, it was confirmed that there is a need to use an operating parameter named effective grounding electrode length, because when it is exceeded, the characteristics of grounding is not significantly improved during conductance of lightning surges. The mathematical model used in the paper was verified in a comparison with laboratory tests conducted by K.S. Stiefanow and with mathematical model described by L. Grcev.
3
Ochrona od skutków zwarć łukowych w nowoczesnej automatyce zabezpieczeniowej
80%
Kapelski D. , Sapuła Ł. , Nogal Ł.
Wiadomości Elektrotechniczne
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2024
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tom R. 92, nr 3
25--28
PL
W artykule przedstawiono wybrane zagadnienia związane ze zwarciami łukowymi występującymi w sieciach średniego napięcia. Omówiono zagrożenia, jakie niesie wystąpienie tego typu zakłócenia wewnątrz rozdzielnicy, zarówno dla zainstalowanej aparatury, jak i ludzi znajdujących się w bezpośrednim sąsiedztwie. Zaprezentowano także sposoby ograniczenia skutków zwarcia łukowego. Szczególną uwagę poświęcono zabezpieczeniom łukoochronnym. Zaprezentowano przykład wykonania bazujący na rozwiązaniu opracowanym w Sieć Badawcza Łukasiewicz – Instytut Tele- i Radiotechniczny. Rozwiązanie to dzięki wprowadzonym dodatkowym kryteriom stabilizacji zadziałania minimalizuje ryzyko zbędnych wyłączeń, natomiast zastosowane algorytmy szybkiego określania wartości RMS sprawiają, że całkowity czas likwidacji zwarcia ulega tylko nieznacznemu wydłużeniu.
EN
The article discusses selected issues related to arc short circuits occurring in medium-voltage lines. It describes the risks associated with the occurrence of such disturbances within the switchgear, both for the installed equipment and for working people in close proximity. The article also presents ways to limit the consequences of arc faults short circuits, with particular emphasis on arc fault protective devices. An example of implementation based on a solution developed at the Lukasiewicz Research Network – Tele and Radio Research Institute is presented. Thanks to the introduced additional stability criteria, this solution minimizes the risk of unnecessary disconnections, while the applied algorithms for rapid determination of RMS current or voltage values result in only a slight extension of the total arc short circuits elimination time in comparison to classical solutions.
4
Content available IEC 61850 interface for real time power system simulation
80%
Kurek K. , Nogal Ł. , Kowalik R. , Januszewski M.
Bulletin of the Polish Academy of Sciences. Technical Sciences
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2021
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tom Vol. 69, nr 3
art. no. e137057
EN
Real time simulators of IEC 61850 compliant protection devices can be implemented without their analogue part, reducing costs and increasing versatility. Implementation of Sampled Values (SV) and GOOSE interfaces to Matlab/Simulink allows for interaction with protection relays in closed loop during power system simulation. Properly configured and synchronized Linux system with Real Time (RT) patch, can be used as a low latency run time environment for Matlab/Simulink generated model. The number of overruns during model execution using proposed SV and GOOSE interfaces with 50 µs step size is minimal. The paper discusses the implementation details and time synchronization methods of IEC 61850 real time simulator implemented in Matlab/Simulink that is built on top of run time environment shown in authors preliminary works and is the further development of them. Correct operation of the proposed solution is evaluated during the hardware-in-the-loop testing of ABB REL670 relay.
5
Content available remote 50 lat Instytutu Elektroenergetyki Politechniki Warszawskiej – historia i dzień dzisiejszy
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Robak S. , Nogal Ł. , Pawlak K.
Przegląd Elektrotechniczny
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2020
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tom R. 96, nr 11
225--229
PL
W roku 2020 Instytut Elektroenergetyki obchodzi Jubileusz 50-lecia. Instytut powstał na skutek zmiany organizacyjnej Politechniki Warszawskiej w 1970 roku, przez połączenie katedr Elektrowni i Gospodarki Elektroenergetycznej, Sieci i Układów Elektroenergetycznych, Elektrotermii i Techniki Świetlnej. Przypadający w roku 2020 jubileusz stanowi okazję do zaznaczenia działań i osiągnięć Instytutu w obszarze zarówno badań naukowych, jak i kształcenia. Ten artykuł prezentuje historią oraz dzień dzisiejszy Instytutu Elektroenergetyki Politechniki Warszawskiej ukazują bogactwo tradycji oraz dorobek społeczności Instytutu.
EN
In 2020, the Electrical Power Engineering Institute celebrate its 50th anniversary. The Institute was established as a result of organizational reform of Warsaw University of Technology in 1970, by merger of the Departments of Power Plants and Electrical Power Economy, Electric Power Networks and Systems, Electrical Thermal Engineering and Light Technology. The jubilee in 2020 is an opportunity to highlight the activities and achievements of Institute both in scientific research and teaching. This paper presents the history and the present day of the Electrical Power Engineering Institute of Warsaw University of Technology showing the richness of tradition and achievements of the Institute's community.
6
Brama zdalnego dostępu do urządzeń automatyki elektroenergetycznej i stawiane jej wymagania
80%
Bartosiewicz E. , Nogal Ł. , Januszewski M.
Elektro Info
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2019
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tom nr 5
86--89
PL
W artykule omówiono koncepcję bramy zdalnego dostępu do urządzeń automatyki elektroenergetycznej. Opisano system zaprojektowany i zaimplementowany zgodnie z wymaganiami krajowego operatora systemu przesyłowego.
EN
The article discusses the concept of a gateway used for remote access to devices belonging to substation automation and protection system. A system designed and implemented in accordance to Polish national transmission system operator requirements is described.
7
Content available Decentralized fault location, isolation and self restoration (FLISR) logic implementation using IEC 61850 GOOSE signals
70%
Bielenica P. , Widzińska J. , Łukaszewski A. , Nogal Ł. , Łukaszewski P.
Bulletin of the Polish Academy of Sciences. Technical Sciences
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2022
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tom Vol. 70, nr 5
art. no. e143101
EN
Fault location, isolation and self-restoration (FLISR) automation is an essential component of smart grids concept. It consists of a high level of comprehensive automation and monitoring of the distribution grid improving the quality of energy supplied to customers. This paper presents an algorithm for decentralized FLISR architecture with peer-to-peer communication using IEC 61860 GOOSE messages. An analysis of short circuit detection was presented due to the method of the grid earthing system. The proposed automation model was built based on communication logic between configured intelligent electronic devices (IED) from ABB and Siemens. The laboratory tests were conducted in a half-loop grid model with a bilateral power supply (typical urban grid). The laboratory research concerned three locations of short circuits: between substation and section point, between two section points and between section point and normally open point (NOP). The logic implementation was developed using State Sequencer software offered by Test Universe.
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