Sliding-mode Observer-based Grid Voltage-observation Method with Frequency-fixed Dual SOGI and Cross-compensated Phase-locked Loop  

作　　者：Leilei Guo Qingyang Ye Nan Jin Zhenkun Liu Zhenjun Wu 

机构地区：[1]School of Electrical and Information Engineering,Zhengzhou University of Light Industry,Zhengzhou 450002,China

出　　处：《Chinese Journal of Electrical Engineering》2024年第3期37-49,共13页中国电气工程学报（英文）

基　　金：Supported by the Outstanding Youth Science Foundation of Henan Province(242300421074);Henan Province Key R&D Project(241111210400,241111242300).

摘　　要：Conventional sliding-mode observer(SMO)-based grid-voltage observation methods often require a low-pass filter(LPF)to remove high-frequency sliding-mode noise.However,a complicated phase-and amplitude-compensation method,which is highly sensitive to the DC-offset,is required.A frequency-adaptive dual second-order generalized integrator(SOGI)can be used to replace the LPF,eliminating the compensation link and the effects of the DC-offset;however,strong coupling is introduced between the front-end SOGI block and back-end phase-locked loop(PLL)block,thereby reducing the dynamic performance.To solve this problem,this study proposes an SMO-based grid-voltage observation method with a frequency-fixed dual SOGI and cross-compensated PLL that can eliminate the frequency coupling between the front-end SOGI block and back-end PLL blocks,thereby increasing its dynamic performance.In this study,the phase and amplitude are compensated simultaneously using the proposed cross-compensation method,achieving an accurate observation of the grid voltage under off-nominal frequencies.An analysis of the small-signal model theoretically verified that the proposed method has good dynamic performance.Finally,the superiority of the proposed method is verified through comparative experiments.

关 键 词：Sliding-mode observer(SMO) low-pass filter(LPF) second-order generalized integrator(SOGI) cross-compensation phase-locked loop(PLL) small-signal model 

分 类 号：TM73[电气工程—电力系统及自动化]