弱电网环境下光伏并网逆变器锁相环研究
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摘要
双二阶广义积分器(DSOGI)可以在电网电压不平衡情况下精确提取电网电压锁相角,但在谐波含量较多的环境下,由于DSOGI对频率的依赖性较强,会导致锁相误差较大,系统不稳定。此处对DSOGI-锁相环(PLL)进行了改进,利用谐波消除模块(HCM)消除电网电压中的谐波分量,有效地降低了谐波对输出相角的影响。仿真和实验结果表明:改进后的PLL能够有效减小弱电网环境下的锁相误差。
Dual second-order generalized interger(DSOGI)can accurately extract the grid voltage phase-locked angle in the case of grid voltage imbalance.However,in the environment with high harmonic,due to the dependence of the DSOGI on the frequency which leads to large phase-locked error and unstable system.DSOGI-phase-locked loop(PLL)is improved.The harmonic cancellation module(HCM)is used to eliminate the harmonic components in the grid voltage which effectively reduces the influence of harmonics on the output phase angle.Simulation and experimental results show that the improved PLL can effectively reduce the phase-locking error in the weak grid environment.
Dual second-order generalized interger(DSOGI)can accurately extract the grid voltage phase-locked angle in the case of grid voltage imbalance.However,in the environment with high harmonic,due to the dependence of the DSOGI on the frequency which leads to large phase-locked error and unstable system.DSOGI-phase-locked loop(PLL)is improved.The harmonic cancellation module(HCM)is used to eliminate the harmonic components in the grid voltage which effectively reduces the influence of harmonics on the output phase angle.Simulation and experimental results show that the improved PLL can effectively reduce the phase-locking error in the weak grid environment.
引文
[1]陈增禄,赵乾坤,史强强,等.一种电网电压过零点精确锁相方法的研究[J].电力系统保护与控制,2014,42(8):65-70.
[2]刘桂花,曹小娇,王卫.弱电网下单相光伏并网逆变器锁频环同步方法[J].中国电机工程学报,2015,35(19):5022-5029.
[3]陈艳艳,沈旦立,皇淼淼,等.基于二阶广义积分器的单相并网锁相环的研究[J].电力电子技术,2013,47(5):46-47.
[4]张学广,付志超,陈文佳,等.弱电网下考虑锁相环影响的并网逆变器改进控制方法[J].电力系统自动化,2018,39(7):139-145.
[5]郭磊,王丹,刁亮,等.针对电网不平衡与谐波的锁相环改进设计[J].电工技术学报,2018,33(6):1390-1399.
[6]回楠木,王大志,李云路.复杂电网下基于双改进型SOGI的三相并网锁相环[J].仪器仪表学报,2018,39(4):123-132.
[7]张纯江,赵晓君,郭忠南,等.二阶广义积分器的三种改进结构及其PLL应用对比分析[J].电工技术学报,2017,32(22):42-49.
[2]刘桂花,曹小娇,王卫.弱电网下单相光伏并网逆变器锁频环同步方法[J].中国电机工程学报,2015,35(19):5022-5029.
[3]陈艳艳,沈旦立,皇淼淼,等.基于二阶广义积分器的单相并网锁相环的研究[J].电力电子技术,2013,47(5):46-47.
[4]张学广,付志超,陈文佳,等.弱电网下考虑锁相环影响的并网逆变器改进控制方法[J].电力系统自动化,2018,39(7):139-145.
[5]郭磊,王丹,刁亮,等.针对电网不平衡与谐波的锁相环改进设计[J].电工技术学报,2018,33(6):1390-1399.
[6]回楠木,王大志,李云路.复杂电网下基于双改进型SOGI的三相并网锁相环[J].仪器仪表学报,2018,39(4):123-132.
[7]张纯江,赵晓君,郭忠南,等.二阶广义积分器的三种改进结构及其PLL应用对比分析[J].电工技术学报,2017,32(22):42-49.