基于频率自适应改进型梳状滤波器的并网锁相环技术

将梳状滤波器应用于并网锁相环技术中。针对梳状滤波器锁相环(CF-PLL)动态响应慢的缺点,引入校正环节,得到改进型梳状滤波器锁相环(ICF-PLL)。基于ICF-PLL的s域模型,提出了ICF-PLL调节器参数的整定方法。为提高ICF-PLL对电网频率变化的抗扰动能力,提出一种基于频率自适应改进型梳状滤波器的锁相环(FAICF-PLL)和其数字实现方案。仿真和实验结果表明,FAICF-PLL在电网电压发生频率脉动、相角变化、畸变谐波和不平衡跌落时均能准确地跟踪电网电压相位,具有良好的稳态和动态性能。

Grid-connected Phase-locked Loop Based on Frequency Adaptive Improved Comb Filter

The comb filter is applied to the field of grid-connected phase-locked loop. The main drawback of traditional comb filter based phase-locked loop(CF-PLL)is the slow dynamic response. The improved comb filter based phase-locked loop(ICF-PLL)is proposed by introducing the correction element. The setting method of parameters for the ICF-PLL controller is proposed based on its s-domain model. In order to improve the disturbance resisting ability of the ICF-PLL when the frequency of the power grid changes, an improved comb filter based frequency adaptive phase-locked loop(FAICF-PLL)and its digital implementation scheme are presented. Simulation and experimental results show that FAICF-PLL has good steady-state and dynamic performance for its accurate phase locking under frequency ripple, phase angle change, distorted harmonic and unbalanced voltage sag grid conditions.