分析了三相四线制四桥臂有源电力滤波器的工作原理,提出基于瞬时无功功率理论的谐波检测方法。建立了四桥臂带输出电感的三相四线制的数学模型。基于dqO坐标系下数学模型,采用电流内环的基于前馈解耦PI控制方法,以及PI参数的设计方法。利用三维空间矢量脉宽调制技术(3D—SVPWM)进行电流跟踪控制逆变器的输出,易于数字实现,直流电压利用率高。通过Matlab仿真及试验证明了三相四线制有源电力滤波器系统对三相不平衡四线制系统的三相谐波及无功电流与中性线电流有效的补偿效果。
The working principle of three-phase four-wire shunt active power filter was analyzed. The detection method based on instantaneous reactive power theory was proposed. Three-phase four-wire shunt active power filte- ring system was built. The current close-loop PI adjustment based on voltage feed forward decoupling was adopted in dqO coordinate system,and the designing method of PI parameters was presented. 3D-SVPWM technic was em- ployed to control current tracking, which is easy of digital realization and high DC-side voltage utilization. The sim- ulation results by Matlab and experimental results show that the three phase four wire power filter can realize three phase harmonic and reactive power currents and neutral line current compensation effectually.