基于EMTDC的三相锁相环仿真及精度的提高

The simulation and presion improving of 3-phase phase-locked loop(PLL) based on EMTDC

通过使用Matlab和PSCAD 2个电力系统分析中常用的软件对三相锁相环(PLL)进行了仿真和研究。将该PLL模型的各个组成部分分别进行了详细的分析,得出了PLL的传递函数。通过Matlab仿真3组不同的参数下,PLL系统的波德图,奈氏曲线,以及阶跃响应,最后得出一组使得锁相环性能优良的数据,精度也较满意。但是在有谐波的情况下,精度不够高,于是在PI控制器后加巴特沃斯低通滤波器和校正环节,含谐波时的精度有明显提高。

This paper presents a method of simulation and research on three-phase phase locked loop （PLL） through Matlab and PSCAD. Each part of PLL model is analysed in detail, then the transfer function of PLL is carried out. PLL system＇ s bode figure. Nyquist curve, and step response is simulated in three different set of parameters by Matlab, and then PLL excellent performance data is worked out, which precision is also satisfactory. However, in the case of harmonic, precision is not high enough. Puting Butterwoth low pass filter and correctioner after the PI controller, precision is improved markedly with the harmonic.