弱电网不对称故障下基于正负序解耦的锁相环设计与研究  

Design and Research of PLL Based on Positive and Negative Sequence Decoupling under Asymmetric Faults in Weak Power Grid

作　　者：马天诚 黄云辉[1] 王栋 王凌云 朱国荣[1] MA Tiancheng;HUANG Yunhui;WANG Dong;WANG Lingyun;ZHU Guorong(School of Automation,Wuhan University of Technology,Wuhan 430070,China)

机构地区：[1]武汉理工大学自动化学院,湖北武汉430070

出　　处：《智慧电力》2022年第1期108-114,共7页Smart Power

基　　金：国家自然科学基金面上资助项目(51777146)。

摘　　要：针对弱电网发生不对称故障下传统锁相环正负序解耦不完全的问题,提出了将四阶广义积分器应用于锁相环进行正负序解耦的思路。首先分析了弱电网不对称故障下传统锁相环引起的问题,揭示了不对称故障时端电压相位和幅值突变产生直流和谐波分量而进一步导致传统锁相环正负序解耦不完全的原因。然后分析了基于四阶广义积分器结构的锁相环的幅频特性和滤波性能,并进行广义积分器比例系数的设计。最后,在Matlab中进行了不同短路比下传统锁相环和基于四阶广义积分器锁相环的仿真对比,表明了所做设计的有效性。In order to solve the problem of the incomplete positive and negative sequence decoupling of the traditional PLL under asymmetric faults in weak power grid,the paper propose an idea of applying a fourth-order generalized integrator(FOGI)to PLL for the positive and negative sequence decoupling.Firstly,the problems caused by the traditional PLL under the asymmetric faults in the weak power grid are analyzed,and expounds the reasons that DC and harmonic components are generated by an abrupt change in the phase and amplitude of terminal voltage during the asymmetric faults and further leading to the incomplete positive and negative sequence decoupling of the traditional PLL.Then the amplitude-frequency characteristics and filtering performance of the phaselocked loop based on the fourth order generalized integrator are analyzed,and the proportional coefficient of the generalized integrator is designed.Finally,the simulation comparison is made between the traditional PLL and the fourth order generalized integrator-based PLL in Matlab with different short circuit ratio,verifying the effectiveness of the design.

关 键 词：弱电网 不对称故障 正负序解耦 四阶广义积分器 

分 类 号：TM614[电气工程—电力系统及自动化]