Modeling and current control strategy for a medium-voltage cascaded multilevel statcom with LCL filter

• Autorzy: Zhao X. , Shi L. , Chen L. , Xia Z. , Bendre A. R.
• Języki publikacji: EN

Abstrakty

EN

The Static Synchronous Compensator (STATCOM a.k.a. SVG) is widely used to regulate dynamic reactive power and to solve dynamic voltage stability problems. Modeling shows that a cascaded STATCOM, which is composed of several cascaded H-bridges, not only has strong coupling characteristics when an LCL filter is added but it is also a non-linear, multivariable system. Therefore, its practical design and application are dicult to implement. In this paper an internal decoupling control algorithm is introduced to provide independent control of the active and reactive currents. Decoupling control algorithms are proposed, and models and simulation of the decoupling are provided. We describe the setting up of a simulation and experiments with a cascaded STATCOM based on combined circuit topology with a multi-field programmable gate array (FPGA), and double-loop control algorithms with a current inner loop, and a capacitor voltage outer loop. To provide control of the current inner loop, proportional-integral (PI) and resonant controllers are used, having the control ability to cancel harmonics while compensating for the reactive power. This paper presents new current-tracing control models that compensate for the fundamental current and eliminate selective harmonics by adopting a d-q synchronous reference frame, and a discrete Fourier transform (DFT). Voltage balance is realized by introducing modulation wave distribution strategies. Furthermore, both simulation and experiments are employed to verify the feasibility and eectiveness of the control strategy.

Słowa kluczowe

EN

cascaded H-bridge; internal model decoupling; resonant controller; distribution of modulation; double-loop control

PL

mostek H; mostek kaskadowy; sterownik rezonansowy; dystrybucja modulacji; podwójna pętla sterowania; sterowanie

• Wydawca: Institute of Heat Engineering, Warsaw University of Technology
• Czasopismo: Journal of Power Technologies
• Rocznik: 2015
• Tom: Vol. 95, nr 1
• Strony: 1--13
• Opis fizyczny: Bibliogr. 15 poz., rys., tab., wykr.

Twórcy

autor

Zhao X.

• School of Information & Electrical Engineering, China University of Mining & Technology, Xuzhou, 221116, China

autor

Shi L.

• School of Information & Electrical Engineering, China University of Mining & Technology, Xuzhou, 221116, China

autor

Chen L.

• School of Information & Electrical Engineering, China University of Mining & Technology, Xuzhou, 221116, China

autor

Xia Z.

• School of Electrical Engineering, Jiangsu Normal University, Xuzhou, 221000, China

autor

Bendre A. R.

• Faculty of Engineering, University of Wollongong, Wollongong NSW, 2522, Australia

Bibliografia

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• [3] Liu Fei, Duan Shanxu, Zha Xiaoming.: Design of two-loop controller in a grid-connected inverter with LCL filters: Proceedings of the CSEE 29(12)(2009)234-240.
• [4] Zhang Dongjiang, Qiu Zhiling, Li Yuling.: Shunt active power filter with high steady-state performance based on LCL-filter: Transactions of China Electrotechnical Society 29(12)(2009)234-240.
• [5] Zhang Xing, Shao Wenchang, Yang Shuying.: Multi-loop control scheme of a grid side converter with LCL-filter: Journal of HeFei University of Technology 32(7)(2005)72-76.
• [6] Zhang Xianping, Lin Zixu, Li Yaxi.: A novel control strategy for PWM rectifier with LCL filter: Transactions of China Electrotechnical Society 22(2)(2007)74-77.
• [7] Leskover S., Marchesini M.: Control techniques for DC-link voltage ripple minimization in cascaded multilevel converter structures: Power Electronics and Application (EPE). Germany: European Power Electronics Association (2005)23-32.
• [8] Wei Wenhui, Liu Wenhua, Song Qiang.: Research on fast dynamic control of static synchronous compensator using cascade multilevel inverters: Proceedings of the CSEE 25(2)(2005)23-26.
• [9] Liserre M., Teodorescu., Blaabjerg F.: Multiple harmonics control for three-phase grid converter systems with the use of PI-RES current controller in a rotating frame: Power Electron 21(3)(2006)836-841.
• [10] Liu Chunxi, Ma Weiming, Sun Chi.: Design of output LC filter and low order harmonics suppression in high power 400Hz inverter: Transactions of China Electrotechnical Society 26(6)(2011)129-137.
• [11] Sozański K P.: Sliding DFT control algorithm for three-phase active power filters: Applied Power Electronics Conference and Exposition, Twenty-First Annual IEEE. USA:IEEE (2006)1223-1229.
• [12] Li Yidan, Lu Wensheng, Peng Xiuyan.: DC voltage measurement and control for cascaded STATCOM: Proceedings of the CSEE 31(1)(2011)14-19.
• [13] Liu Wenhua, Song Qiang, Teng Letian.: Balancing control of DC voltages of 50MVA STATCOM on cascade multilevel inverters: Proceedings of the CSEE 24(4)(2004)145-150.
• [14] Ren Mingwei, Sun Yukun.: Voltage balance control of DC capacitors of 11-level cascade STATCOM: Automation of Electric Power Systems 4(6)(2010)10-15.
• [15] Hu Yinghong, Ren Jiajia, Wang Jianze.: Balancing control method of DC voltage of cascaded H-bridge STATCOM: Electric Machines and Control 14(11)(2010)31-36.