A novel dynamic voltage restorer and its unbalanced control strategy based on space vector PWM

• Published in: International journal of electrical power & energy systems 2002-11, Vol.24 (9), p.693-699
• Main Authors: Ding, Hongfa, Shuangyan, Shu, Xianzhong, Duan, Jun, Gao
• Format: Article
• Language: English
• Subjects: Applied sciences; Disturbances. Regulation. Protection; Dynamic voltage restorer; Electrical engineering. Electrical power engineering; Electrical power engineering; Emitter follower; Exact sciences and technology; Power electronics, power supplies; Power networks and lines; PWM inverter; Space vector; Three-phase voltage unbalance; Unbalanced control strategy
• ISSN: 0142-0615; 1879-3517
• DOI: 10.1016/S0142-0615(02)00004-2

A novel dynamic voltage restorer which is composed of a conventional three-phase voltage source inverter and an emitter follower is presented in this paper to reduce the adverse effects on sensitive loads caused by three-phase supply voltage unbalance in distribution systems. The adverse effect caused by the negative sequence component of the supply voltage can be eliminated and the load voltage magnitude can be restored to specified value by using the three-phase voltage-source inverter. The emitter follower is capable of eliminating the adverse effect caused by the zero sequence component of the supply voltage. An unbalanced control strategy based on space vector PWM is presented to realize the fast dynamic response of the dynamic voltage restorer. Feasibility of this method is verified by digital simulation.