基于广义积分器的电力单相锁相环研究

Study on Control Strategy for Single-phase Power Phase-locked Loop with Generalized Integrator

针对目前软件锁相环技术存在锁相误差及滤波延时的不足,笔者基于瞬时无功理论的单相锁相环技术,提出一种通过二阶广义积分器来构造正交信号的方法。并对输入电压存在直流分量的情况下,分析了正交电压分量输出的偏移情况,设计一个前馈低通滤波器后,性能有了明显的改善。最后通过在PSCAD/EMTDC中单相可控并联无功补偿(TCPC)系统仿真的基础上验证了该方案可以有效提高锁相精度并对电压畸变有较强的抑制作用,因此适用于实际的单相系统。

There are big phase-locked errors in current techniques of software phase-locked loop and the time-delayed in the filter.A new design method of orthogonal signal generation with second order Generalized Integrator was proposed based on analysis of instantaneous reactive power theory used in single-phase phased-locked loop.In case of DC component exist in the input voltage signal,the orthogonal voltage signal was analyzed,after the design process of a feed forward low-pass filter,the performance have been improved significantly.Finally,single-phase controllable parallel reactive power compensation system was built in PSCAD/EMTDC.From the simulation results,it is demonstrated that proposed method can improve the accuracy of phase-locked effectively and reject voltage distortion strongly,so it has a practical value for single-phase system.