光伏并网逆变器虚拟电机准直接功率控制

Virtual Machine Quasi DPC on Photovoltaic Grid-connected Inverter

为提高光伏并网系统抗干扰能力,提出一种虚拟电机准直接功率控制(DPC)。构造出虚拟电机磁链作为逆变器的定向矢量,既能省掉交流侧电压传感器,又能滤除一部分谐波;同时,a,b,c自然坐标系控制实现了有功和无功的独立控制,无需锁相环(PLL),易于实现,可靠性高。实验结果表明基于自然坐标系的虚拟电机DPC策略使逆变器运行于单位功率因数,且能在一定范围内实现无模型控制,系统具有良好动、静态特性和鲁棒性。

In order to improve capacity of resisting disturbance, a virtual motor quasi direct power control （DPC） strat- egy is proposed.The oriented vectors of the inverters are constructed according to the virtual motor flux.As a result, the alternating current voltage sensors are cancelled and some of harmonic is eliminated effectively.Meanwhile, the in- dependent control for active and reactive power is implemented in the a,b ,c natural coordinate.The method don＇t need phase-locked loop.Moreover,it is easy to implement and has high reliability.Experimental results show that vir- tual motor quasi DPC in natural coordinates can make the inverter run at unity power factor, and realize no model control within a certain range.The system has good dynamic and static characteristics and robustness.