Research on Control Strategy of Back-to-back VSC and Its Isolation Ability to Power Quality Problems

doi:10.11985/2020.03.016

Abstract

Abstract:

With the application of power electronic equipment in the distribution network, it has brought many benefits to the safe and reliable operation of the traditional distribution network and promoted the development of the intelligent distribution network. Soft normally open point(SNOP) is a new type of power electronic equipment that replaces traditional mechanical switches. As a kind of SNOP, back-to-back voltage source converter (B2B VSC), may replace some interconnection switches or section switches in the traditional distribution network in the future, improving the flexibility of the distribution network operation. The operation mode of B2B VSC and the control strategy under different working conditions are described in detail. In view of the typical power quality problems in distribution network, the isolation ability of B2B VSC to typical power quality problems is discussed, and finally verified by simulation and experiment.

Key words: SNOP, back-to-back voltage source converter, power quality, isolation ability

CLC Number:

TM561

JIN Qingren,GUO Min,YAO Zhiyang. Research on Control Strategy of Back-to-back VSC and Its Isolation Ability to Power Quality Problems[J]. Journal of Electrical Engineering, 2020, 15(3): 120-127.

Figures/Tables 17

References 14

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交/直流侧	元器件	参数
VSC1	电压源/V	311
	滤波电感/mH	1.5
	滤波电容/μF	50
VSC2	负载/Ω	5
	滤波电感/mH	1.5
	滤波电容/μF	50
直流侧	电容/μF	2 200

	VSC1(扰动侧)	VSC2(负载侧)
电压谐波	电压总畸变 THD=15.8% 电流总畸变 THD=5.6%	电压总畸变 THD=0.9% 电流总畸变 THD=0.9%
电压暂降	暂降深度80%	未发生暂降
三相电压不平衡度(%)	4.2	3.1