基于二阶广义积分器单相锁频环的改进和比较  

Improvement and Comparison of Single-Phase Frequency Locked Loops Based on Second Order Generalized Integrator

作　　者：戴朝波 赵国亮 杨志昌 崔镜心 DAI Chaobo;ZHAO Guoliang;YANG Zhichang;CUI Jingxin(State Key Laboratory of Advanced Power Transmission Technology(China Electric Power Research Institute Co.,Ltd.),Beijing 102209,China)

机构地区：[1]先进输电技术全国重点实验室(中国电力科学研究院有限公司),北京102209

出　　处：《中国电力》2025年第1期61-69,共9页Electric Power

基　　金：国家电网有限公司科技项目(5500-202158475A-0-5-ZN)。

摘　　要：电网受到短路故障等大扰动时,要求并网换流器快速准确获得同步信息。基于二阶广义积分器的锁频环比锁相环能更快获取电网电压的相位、幅值和频率,但受直流偏移的不利影响。基于抑制法和滤波法的改进方案存在响应速度变慢等不足。为此,提出基于消减法的改进方案,并在锁频环中增加二阶广义积分器环节。应用传递函数和PSCAD商业软件,从理论和仿真2方面分析和比较了基于二阶广义积分器锁频环的基本方案、基于抑制法的改进方案和所提基于消减法的改进方案。比较结果显示,基于消减法的改进方案具有更快的相位、幅值和频率响应特性,更好的直流和低频分量抑制特性。综合比较暂态响应和稳态响应,基于消减法的方案性能最优。It is required for grid-connected converters to obtain synchronous information quickly and accurately when a short-circuit fault occurs in the grid.Compared with the phase locked loop(PLL),the second order generalized integrator(SOGI)-frequency locked loop(FLL)promises faster detection of the phase,amplitude and frequency of the grid voltage,but becomes susceptible to the effect of a direct current(DC)offset.Modified schemes based on the suppression method and the filtering method have drawback of slower response.A modified scheme based on the subtraction method is proposed with an addition of a SOGI block in the FLL.The basic scheme based on SOGI-FLL,the modified scheme based on the suppression method and the proposed scheme based on the subtraction method are analyzed and compared by transfer functions theoretically and simulations of PSCAD commercial software.Comparison results illustrate that the subtraction-based scheme promises faster detection of the phase,amplitude and frequency of the grid voltage,and better suppression of the DC offset and low frequency components.Taking account of respective transient and steady-state response characteristics,the subtraction-based scheme has the best comprehensive properties.

关 键 词：二阶广义积分器 锁频环 锁相环 同步 直流偏移 抑制法 消减法 

分 类 号：TN911.8[电子电信—通信与信息系统] TM73[电子电信—信息与通信工程]