中国电机工程学报Issue(18)：4744-4752,9.DOI:10.13334/j.0258-8013.pcsee.2015.18.022
不平衡电网下无锁相环三相并网逆变器控制策略
Control Strategies of Three-phase Grid-connected Inverters Without Phase-lock Loop Under Unbalanced Grids
摘要
Abstract
Ingrid-connected power generation systems, the rapid and accurate phase synchronization detection is the foundation for control. The paper analyzes the effect of unbalanced grids on three-phase inverters with the traditional phase locked loop (PLL). When the grid voltage unbalance exists, the detection of grid voltage and the calculation of phase angles have errors, which would influence the control precision. Hence, the paper proposes two space vector pulse width module (SVPWM) control strategies without PLL for three-phase grid-connected inverters: direct power control strategy and direct current control strategy, and builds the mathematical models to verify the feasibility. The two strategies separate the positive sequence voltage component from the rotating synchronousdq frame and theαβ frame respectively. The paper also compares non-PLL strategies with traditional PLL strategy under unbalanced grid voltages and summarized and compares the two non-PLL strategies. The simulation and experimental results show that the non-PLL strategies can accurately and rapidly extract the positive sequences from unbalanced grid voltages compared with PLL. What’s more, the dynamic response of direct current control strategy is even better than that of direct power control strategy.关键词
无锁相环/三相逆变器/空间矢量脉宽调制技术/坐标变换/正序分量Key words
without PLL/three-phase inverter/SVPWM/coordinate transformation/positive sequence分类
信息技术与安全科学引用本文复制引用
雷芸,肖岚,郑昕昕..不平衡电网下无锁相环三相并网逆变器控制策略[J].中国电机工程学报,2015,(18):4744-4752,9.基金项目
国家自然科学基金项目(51377082)；江苏省产学研前瞻性联合研究项目(BY2012021)；江苏省“青蓝工程”项目。Project Supported by National Natural Science Foundation of China (51377082) （51377082）
Project of Jiangsu Province Prospective Joint Research Project (BY2012021) （BY2012021）
Jangsu Qing Lan Project． （）
