基于内模控制的三相电压型PWM整流器不平衡控制策略研究

STUDY OF INTERNAL MODEL CONTROL BASED THREE-PHASE PWM RECTIFIER UNDER UNBALANCED INPUT VOLTAGE CONDITION

该文提出了在αβ静止坐标系中采用内模控制的三相VSR不平衡控制方案,不仅实现了正负序电流的无差跟踪控制,而且使系统获得了强鲁棒性;另外,该文还提出了一种不平衡指令电流算法,实现了电网不平衡时三相VSR平均有功、无功功率的独立控制,解决了以往不平衡指令电流算法只能实现三相VSR单位功率因数运行的局限性。样机试验论证了理论分析的正确性。

A novel control strategy of three phase VSR under unbalanced input voltage condition is proposed in this paper. With the Internal Model Control (IMC) concept, the unbalanced control system not only achieve zero steady state error of positive and negative current, but also obtains strong robustness of the control system. Furthermore, The newly proposed control strategy can both eliminate the dc voltage harmonics and control the average active and reactive power of the VSR respectively. Theoretical analysis and experimental results verify the correctness of the proposed control strategy.