基于直流侧保护的并网光伏发电系统低电压运行特性分析

Low-voltage Operation of Grid-connected PV System with DC Side Protection

针对PSCAD\EMTDC软件利用FORTRAN语言编程,建立了光伏阵列及MPPT控制器通用仿真模型。分析流侧保护电路的原理,研究了在电网电压跌落后直流侧保护电路投切控制策略。并在PSCAD/EMTDC仿真软件中搭建了双极型光伏发电系统模型,针对电网三相对称短路故障下直流侧保护电路的投切策略进行了仿真研究。仿真结果验证了所提策略能实现光伏发电系统的低电压穿越。

Simulation models of PV array and MPPT controller are established by programming in FORTRAN language for PSCAD／EMTDC software. On the basis of analyzing DC side protection circuit topology, tiffs research focuses on the switching control strategy for DC side protection circuit after voltage sag of power grid. Within PSCAD/EMTDC simulation software, the model is set up for bipolar PV power generation system. Then the switching control strategy.. for DC side protection circuit is simulated in the case of three-phase symmetrical short-circuit fault of power grid. The simulation results show that the proposed method can realized the LVRT of PV power system.