网压不平衡下并网逆变器的控制方案研究  

Grid- connected inverter control strategy under unbalanced grid voltage

作　　者：齐飞[1] 李建文[1] 李永刚[1] 孙伟[2] 张舒怡[1] 

机构地区：[1]华北电力大学电气与电子工程学院,河北保定071003 [2]国家电网保定市供电公司,河北保定071000

出　　处：《电测与仪表》2016年第12期62-68,86,共8页Electrical Measurement & Instrumentation

基　　金：国家自然科学基金资助项目(51277072);中央高校基本科研业务费专项资金项目(12MS108)

摘　　要：针对电网电压不平衡时光伏并网逆变器功率波动与并网谐波电流畸变率大的问题,提出一种静止坐标系下采用准比例谐振控制的LCL滤波器的三相并网逆变器不平衡控制方案。首先以有功功率无波动为控制目标,采用瞬时功率理论推导出并网给定的电流指令,给出了电网电压正负序的获取方法,然后利用LCL滤波器的高效滤波特性,在αβ静止坐标系下建立了基于QPR调节器的有源阻尼的并网模型,最后在MATLAB/SIMULINK平台上进行了仿真验证,结果表明在电网电压出现不平衡时,控制系统能够抑制输出有功功率的2倍频振荡,且并网电流谐波畸变率低,从而验证了控制策略的有效性。In order to suppress the power fluctuations and high level of current harmonic distortion rate when the power grid occurs unbalanced grid voltage,this paper proposes a control strategy of grid-connected inverter with LCL filter based on quasi proportional resonant in static coordinates. Firstly,in order to suppress the active power fluctuation,grid-given current is deduced by using instantaneous power theory. The positive and negative sequence of power grid voltage acquisition method is presented. The high efficiency filter characteristic of the LCL filter is used to establish the grid-connection model based on active damping with QPR regulator in αβ static coordinates. Finally,simulation model is founded on the MATLAB / SIMULINK platform. The simulation results show that the control system can eliminate the double times oscillations of the output active power and achieve low level of current harmonic distortion rate,and verity the effectiveness of the proposed strategy.

关 键 词：网压不平衡 双二阶广义积分器 功率振荡 准比例谐振控制 LCL滤波器 

分 类 号：TM933[电气工程—电力电子与电力传动]