Study of the Control System of Three-level PWM Rectifier Based on Virtual Flux Oriented
This paper presents a novel decoupling control strategy for three-level NPC PWM rectifier without line voltage sensors, combining virtual flux oriented control (VOFC) with traditional direct current control based on the decoupled d-q frame. A virtual flux linkage vector can be constructed similarly to the observation of AC motor flux linkage, which may serve as the oriented vector in the vector control of the PWM rectifier instead of the line voltage vector. As a result, the AC voltage sensors and phase locked circuit will be eliminated and the costs of PWM rectifier can be reduced. According to the design principle of AC motor flux observer, a modified virtual grid flux observer and the grid voltage estimation method are proposed, which solves the DC drift problem caused by a wrong initial value selecting of integer in virtual flux oriented vector control for PWM rectifier. Finally based on Matlab/Simulink, this paper constructs virtual flux oriented current decoupling control simulation model of three-level PWM rectifier without grid voltage sensor. The reliability of the observer has been proved. The good dynamic and static performances of the control scheme have been showed by simulation.
three-level rectifier decoupling control system without voltage sensors VFOC simulation
Chunyuan Bian Chenglong Shi Chonghui Song Anna Wang
College of Information Science and Engineering Northeastern University Shenyang, China
国际会议
杭州
英文
288-291
2011-08-26（万方平台首次上网日期，不代表论文的发表时间）