一种改进型锁相环的性能分析

Performance Analysis of A Kind of Improved Phase-Locked Loop

锁相环广泛用于现代工业控制尤其是电网电压相位锁定中,其性能直接影响电网电压频率、相位检测的准确与否。在改进型锁相环(IPLL)的基础上,分析环路稳定的充要条件,提供环路稳定的判据和仿真方法。基于Matlab/simulink对其主要性能进行数字时域仿真分析。仿真结果表明:该结构不但可以对相位阶跃、相位斜升和相位加速度实现跟踪,还可以跟踪输入信号的幅值变化,对输入信号相位变化的跟踪能力可以解决提出问题。利用改进型锁相环的功能,可以将其应用于基于幅值、相位和频率为主要参数解决问题的电力系统领域,如电力系统保护、并网变换器、电能质量分析以及无功补偿等领域。

Phase-locked loop(PLL) is widely used in modern industrial control, especially the grid voltage phase locking, and its performance directly affects the accuracy of power grid voltage frequency and phase detection. Based on the improved phase-locked loop(IPLL), the sufficient and necessary condition of loop stability were analyzed for providing the loop stability criterion and the simulation method. Time-domain simulation analysis for main characters was conducted based on Matlab/simulink. The results showed that IPLL could track phase step, phase ramp, phase acceleration and amplitude changes. The improved phaselocked loop can be applied to the power system domain based on amplitude, phase and frequency as the main parameters to solve the problem, such as power system protection, grid converter, power quality analysis and reactive power compensation, etc.