在电网电压频率波动或者三相不平衡的情况下,硬件锁相很难准确检测到基波正序的相位。在结合PWM整流器空间矢量解耦控制算法的基础上,将软件锁相环技术应用在PWM整流器控制系统中,并用仿真和实验验证了该方案的可行性。实验结果表明,该方案解决了电网电压频率波动及三相不平衡时的相位同步等问题,并在工程上具有一定参考价值。-Frequency or voltage fluctuations in three-phase unbalanced case, the hardware lock is difficult to accurately detect the fundamental positive sequence phase. In the space vector PWM rectifier with decoupling control algorithm based on the software used in the PWM rectifier PLL control system, and use simulation and experimental verification of the feasibility. Experimental results show that the solutions to address the voltage and frequency fluctuations of the phase unbalanced three-phase synchronization issues, and the project has a certain reference value.