Effect of SF6 circuit breaker parameters on switching overvoltages evaluated based on nominal modes of converter transformers

In this work, we set out to investigate the influence of operating currents of SF6 circuit breakers on the magnitude of overvoltages during switching of converter transformers. The experience of electrical equipment operation is analyzed with a focus on the problems associated with the natural aging of insulation, overloads, and switching overvoltages. The methods of equipment diagnostics were used. According to statistical data, at present, about 37% of short circuits between phases and 42% of single-phase earth faults in electrical networks of industrial enterprises occur due to switching overvoltages. The conducted tests showed that the overvoltages emerging during switching by SF6 circuit breakers of converter transformers, which are used in aluminum smelters, may reach a three-fold rated voltage of the network. This threatens the insulation of transformer windings, cable line, and the switch itself. It was established that an increase in operating currents of an LF2 circuit breaker, not exceeding 27.8% of the rated current of the switch, leads to an increase in overvoltages during switching of converter transformers. At a further increase in the operating currents of the circuit breaker by more than 27.8% of the rated current of the circuit breaker, a sharp decrease in the value of switching overvoltages is observed. Therefore, the operating currents of SF6 circuit breakers were established to affect the level of switching overvoltages of converter transformers. The underlying mechanism of this phenomenon was determined, which should be taken into account when improving the reliability of power supply of converter transformers and, consequently, the reliability of aluminum production. The feasibly of resistive-capacitive dampers as the most effective means for limiting overvoltages during switching of converter transformers was confirmed.

1. Bohmat I.S. Energy consumption features of aluminum industry enterprises. In: Alyuminievaya promyshlennost’ i elektroenergetika: real’nost’ i perspektivy: materialy otkrytogo seminara = Aluminum industry and electric power industry: reality and promises: materials of the open seminar. 30 March 2004, Moscow. Moscow: The Institute of Economic Forecasting of the RAS; 2004, р. 4-18. (In Russ.).

2. Kugusheva NN, Semenov AS, Yakushev IA, Pavlova SN. Technical and economic features of choice of frequencycontrolled electric drives for technological units of diamond mining enterprises. Innovation & Investment. 2021;1:145-149. (In Russ.). EDN: NBMMNS.

3. Brykalov S.M., Balyberdin A.S., Trifonov V.Yu., Zasukhin R.V. Key approaches to energy efficiency improvement at large manufacturing companies. Energy Safety and Energy Economy. 2020;5:10-18. (In Russ.). https://doi.org/10.18635/2071-2219-2020-5-10-18. EDN: UYSLEK.

4. Semyonov A.S., Egorov A.N., Haritonov Ya.S., Bebihov Yu.V., Yakushev I.A., Fedorov A.V. Analysis of the operation of variable-frequency electric drive systems under the influence of high harmonics. In: Elektrotekhnicheskie sistemy i kompleksy: sbornik nauchnyh trudov Mezhdunarodnoj nauchno-prakticheskoj konferencii = Electrical engineering systems and complexes: Collected scientific works of the International scientific and practical conference. 22–25 October 2019, Ufa. Ufa: Ufa University of Science and Technology; 2019, р. 178-184. (In Russ.). EDN: CDLION.

5. Egorov A.N., Semenov A.S., Fedorov O.V. The practical experience of the application of the frequency converter power flex 7000 in the mining industry. Trudy Nizhegorodskogo gosudarstvennogo tekhnicheskogo universiteta imeni R.E. Alekseeva. 2017;4:86-93. (In Russ.). EDN: YMIGZU.

6. Klunduk G.A. Influence of a frequency converter on the power saving of a pump unit and electromagnetic compatibility of equipment. In: Nauka i obrazovanie. Opyt, problemy, perspektivy razvitiya: sbornik nauchnyh trudov Mezhdunarodnoj nauchno-prakticheskoj konferencii = Science and Education. Experience, problems, development prospects: Collected scientific works of the International scientific and practical conference. 21–23 April 2020, Krasnoyarsk. Krasnoyarsk: Krasnoyarsk State Agrarian University; 2020, vol. 1, p. 153-157. (In Russ.). EDN: CQCWQD.

7. Bebikhov Yu.V., Egorov A.N., Matul G.A., Semenov A.S., Kharitonov Ya.S. Search of ways to improve the efficiency of application of high-voltage frequency-regulated electric drive in conditions of mining production. Natural and Technical Sciences. 2018;8:228-234. (In Russ.). EDN: XYUMDB.

8. Shevyrev Yu.V., Shevyreva N.Yu. Improvement of voltage waveform in power supply systems with dynamic rectifier in mineral mining and processing industry. Gornyi Zhurnal. 2019;1:66-69. (In Russ.). https://doi.org/10.17580/gzh.2019.01.14. EDN: VTVWHN.

9. Ashraf N., Abbas G., Abbassi R., Jerbi H. Power quality analysis of the output voltage of AC voltage and frequency controllers realized with various voltage control techniques. Applied Sciences (Switzerland). 2021;11(2). https://doi.org/10.3390/app11020538.

10. Dutta N, Kaliannan P, Subramaniam U. Experimental analysis of PQ parameter estimation of VFD drives. In: Materials Science and Engineering: IOP Conference Series. 2020;937(2):012042. https://doi.org/10.1088/1757899X/937/1/012042.

11. Jyothi R., Sumitgupta, Rao K.U., Jayapal R. IoT application for real-time condition monitoring of voltage source inverter driven induction motor. In: Innovative Data Communication Technologies and Application. 2021;59:97-105. https://doi.org/10.1007/978-981-15-9651-3_8.

12. Skakunov D.A. Influence of power electronics on electric power quality and methods of higher harmonics filtering. In: Trudy vserossiiskoi nauchno-tekhnicheskoi konferentsii = Proceedings of All-Russian Scientific and Technical Conference. 2004, Novokuznetsk. Novokuznetsk; 2004, vol. 1, p. 253-257. (In Russ.).

13. Kaganov V.I. A possible way of energy-savings with pulse method of an electrolysis process in aluminum production. Energosberezhenie i energoeffektivnost’. 2013;2:20-24. (In Russ.). EDN: QAOKGN.

14. Mintsis M.Ya., Polyakov P.V., Sirazutdinov G.A. Electrometallurgy of aluminum. Novosibirsk: Nauka; 2001, 368 р. (In Russ.).

15. Vozdvizhenskij V.A., Goncharov A.F., Kozlov V.B., Nagaryov S.V., Epshtejn I.Ya. Vacuum switches in electric motor control circuits. Moscow: Energoatomizdat; 1988, 200 р. (In Russ.).

16. Gindulin F.A., Gol’dshtejn V.G., Dul’zon A.A., Halilov F.H. Overvoltage in 6-35 kV networks. Moscow: Energoatomizdat; 1989, 90 р. (In Russ.).

17. Akagi H. Active harmonic filters. Proceedings of the IEEE. 2005;93(12):2128-2141.

18. Kuz’min S.V. Using power transformers for higher harmonics localization in 0.4 – 10 kV power supply systems. In: Energoeffektivnost’ sistem zhizneobespecheniya goroda: Trudy vserossiiskoi nauuchno-prakticheskoi konferentsii = Energy efficiency of city life support systems: Proceedings of All-Russian Scientific and Practical Conference. 2009, Krasnoyarsk. Krasnoyarsk; 2009, vol. 1, p. 268–270. (In Russ.).

19. Kuzmin R.S., Kuzmin I.S., Menshikov V.A., Kuzmin S.V., Kulikovskii V.S. Method of assessment and prediction of overvoltage caused by single-phase arc ground short circuits in the 6–10 kV mains as a way of increasing the electrical safety level in mining facilities. Izvestiya vysshikh uchebnykh zavedenii. Gornyi zhurnal. 2020;5:116-132. (In Russ.). https://doi.org/10.21440/0536-1028-2020-5-116-132. EDN: JCGATU.

20. Kuzmin S.V., Mainagashev R.A., Gavrilova E.V., Nemkov S.V. The experience of operating the protection means against the commutation overvoltage in the systems of supplying mining companies with 6 kV electric power. Mining equipment and electromechanics. 2011;4:53-54. (In Russ.). EDN: NRAJPZ.

21. Kuzmin S.V., Umetskaia E.V., Zavalov A.A. Influence of power quality on value of switching overvoltages in networks 6–10 kV. In: International Multi-Conference on Industrial Engineering and Modern Technologies. 2020. https://doi.org/10.1109/FarEastCon50210.2020.9271527.

22. Sowa P., Macha D. Electromagnetic switching transients in transmission line cooperating with the local subsystem. International Journal of GEOMATE. 2020;19(72):180-189. https://doi.org/10.21660/2020.72.5781.

23. Guo Yaxun, Jiang Xiaofeng, Chen Yun, Zheng Ming, Liu Gang, Li Xiaohua, Tang Wenhu. Reignition overvoltages induced by vacuum circuit breakers and its suppression in offshore wind farms. International Journal of Electrical Power & Energy Systems. 2020;122:106227. https://doi.org/10.1016/j.ijepes.2020.106227.

24. Fritz N., Engelmann G., De Doncker R.W. RC snubber design procedure for enhanced oscillation damping in wide-bandgap switching cells. In: 21st European Conference on Power Electronics and Applications. 2019. https://doi.org/10.23919/EPE.2019.8915541.

25. De Paula dos Santos D., Sartori C.A.F. Impact of mismatch cables impedances on active motor terminal overvoltage mitigation using parallel voltage source inverters. In: IEEE 3rd Global Electromagnetic Compatibility Conference. 2017. https://doi.org/10.1109/GEMCCON.2017.8400662.

26. Kuzmin S.V., Gavrilova E.V., Baryshnikov D.V. The influence of the arc extinction process in high-voltage switches on the communication overvoltage value appearing in the 6–10 kV circuits of mining enterprises. Mining equipment and electromechanics. 2009;2:41-44. (In Russ.). JWVZWF.

27. Mesyats G.A. Pulsed power and electronics. Moscow: Nauka; 2004, 704 p. (In Russ.).

28. Tikhonov K.V. Study of switching overvoltages in electrical networks up to 1000 V. iPolytech Journal. 2023;27(2):370-379. (In Russ.). https://doi.org/10.21285/1814-3520-2023-2-370-379. EDN: LTHUGJ.