电力系统自动化2013，Vol.37Issue(14)：107-112,6.DOI:10.7500/AEPS201209129
电网谐波背景下单相并网逆变器的锁相方法
Phase-locked Loop for Single Phase Grid-connected Inverters in a Harmonic Distorted Grid
摘要
Abstract
Based on the fact that the grid voltage of distribution network with distributed generators connected usually contains low order harmonics caused by adjacent nonlinear loads,a phase-locked loop (PLL) structure is proposed for single phase gridconnected inverters.The proposed method has a coupling feedback structure composed of a main module and multi notch filters,in which the main module aims to estimate fundamental component and multi notch filters aim to get harmonic components.The main module is an amplitude-frequency-phase-locked loop (AFPLL) using gradient descent method.The harmonic modules are simple second order notch filters (NFs).The complex structure can eliminate steady state errors in dealing with harmonic distorted grid voltage.Finally,the proposed PLL is verified by harmonic distorted grid voltage synchronization experiment,phase mutation experiment,amplitude mutation experiment and frequency mutation experiment.The experimental results show that the proposed PLL not only can eliminate steady state error in harmonic distorted grid voltage,but also has a quick response when grid voltage suddenly changes.关键词
分布式电源/并网逆变器/锁相环/谐波/梯度下降法/陷波器Key words
distributed generator/ grid-connected inverters/ phase-locked loop (PLL) / harmonics/ gradient descent method/ notch filter引用本文复制引用
王鹿军,张冲,吕征宇..电网谐波背景下单相并网逆变器的锁相方法[J].电力系统自动化,2013,37(14):107-112,6.基金项目
国家自然科学基金资助项目(51177148).This work is supported by National Natural Science Foundation of China (No.51177148). （51177148）
