基于改进瞬时无功理论的单相锁相环

Single-phase Phase-Locked Loop based on Modified Instantaneous Reactive Power Theory

对基于瞬时无功理论的单相锁相环进行了分析,在此基础上将改进瞬时无功理论应用在单相锁相环中。该锁相环采用滞后90°的方法在单相系统中构造出虚拟的两相电压和电流,同时将瞬时功率作为给定,通过PI环节的调节作用达到锁相的目的。仿真和实验结果均验证了该算法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。

Based on the analysis of instantaneous reactive power theory, the modified instantaneous reactive power theory is applied to single-phase phase-locked loop （PLL）.The fictitious two-phase voltage and current are obtained by introducing a lag of 90° in the measured single-phase voltage in the single-phase PLL using the instantaneous active power as the reference signal of PLL,and a PI controller is applied to achieve the purpose of phase-locked.Both simulative and experimental results show that the algorithm can effectively improve the accuracy of phase-locked and has a strong inhibitory effect on distorted voltage, so it is suitable for the actual application in single-phase system.