光伏并网逆变器电能质量控制策略

Power quality control strategy of photovoltaic grid-connected inverter

针对由配电网存在大量非线性负载和光伏发电系统本身间歇性引起的谐波和电压波动问题,提出一种基于瞬时无功功率理论的改进型光伏并网逆变器控制策略,通过采用直流侧电压控制方式稳定逆变器直流侧电压,增加三相交流电压幅值反馈稳定PCC点电压,有效改善了光伏并网及配电系统的电能质量。最后,通过MATLAB/Simulink搭建光伏并网发电系统进行仿真,仿真结果验证了该控制策略的可行性。

The existence of nonlinear loads in distribution network and the intermittent working of photovoltaic power generation system cause the harmonics and voltage fluctuation. Considering of the power quality problem, an improved grid-connected inverter control method based on instantaneous reactive power theory was proposed in this paper. The DC side voltage control was used to stabilize the inverter DC side voltage, and the three-phase voltage feedback was added to adjust the stable voltage of PCC, which effectively improved the power quality of photovoltaic grid-connected generation system and power distribution system. The simulation model of photovoltaic grid-connected generation system was built by MATLAB/Simulink, the simulation results verified the feasibility of the improved control strategy.