准Z源光伏并网逆变器无功补偿自然坐标控制

Nature Coordinate Control of Reactive Power Compensation Based on Quasi-Z-source Photovoltaic Grid Inverter

准Z源逆变器因为其特殊优势,而在光伏并网中得到广泛应用,但是只向电网传输有功电能的光伏发电系统不能控制和改善电网的电能质量。针对分布式发电中常见的电能质量高渗透率问题,在准Z源逆变器的基础上设计了一种既能够光伏并网发电,又能实现无功补偿的统一控制系统(PG-STATCOM),并针对此系统引入自然坐标控制策略,实现有功和无功的独立控制,无需锁相环,计算简单,节约时间。仿真和实验表明系统具有良好的稳定性和鲁棒性。

Quasi-Z-source inverter is widely used in the photovoltaic （PV） grid because of its special advantages, but the PV power generation system which only transports active power to grid can＇t control or improve power quality. Considering the problem of high power quality permeability appeared in distributed generation, a PV grid and static synchronous compensator system （PG-STATCOM） that not only can implement grid-connection of PV generation but also can implement reactive power compensation was designed. The nature coordinate control strategy was introduced for this system. Meanwhile, the independent control of active power and reactive power was implemented in natural coordinate. The method is simple, doesn＇t need phase locking loop and saves considerable time. Simulation and experimental results verify the system＇s excellent stability and robustness.