孤岛微网中基于虚拟负阻抗的改进下垂控制  

Improved Droop Control Strategy Based on Virtual Negative Impedance in Islanded Micro-grid

作　　者：郭诚[1] 顾军[1] 张武[1] 索亚楠 喻景康 罗心宇[1] 

机构地区：[1]安徽理工大学电气与信息工程学院,安徽淮南232001

出　　处：《电气传动》2016年第6期49-53,共5页Electric Drive

摘　　要：在微电网多逆变器并联系统中,每个分布式电源(DG)与公共接入点(PCC)之间的距离各不相同,导致各个单元的线路阻抗存在差异,此时采用传统下垂控制,无功功率将无法得到有效均分;且由于线路阻抗及下垂控制器的作用,DG单元的输出电压幅值出现较大降落。首先对无功功率无法均分的原因进行了分析,在此基础上,针对传统下垂控制的缺陷提出一种基于虚拟负阻抗的改进下垂控制方法。仿真结果表明,该改进型下垂控制策略既能实现对无功的有效均分,也能有效减小系统的输出电压幅值降落。In microgrid system with paralleled multiple inverters,because the distance between the distributedgenerations(DG)and the point of common coupling(PCC)is not same,the line impedance of each DG units isdifferent,and the used traditional droop control can not share the reactive power effectively. And due to the effect ofthe line impedance and droop controller,big reduction for the output voltage amplitude of DG unit occurs. First,thereasons for that the traditional droop control can not share the reactive power effectively were analyzed in detail;then,for the shortcomings of traditional droop control,an improved droop control method basing on virtual negativeresistance was presented. The simulation results show that the improved droop control strategy can reduce systemoutput voltage drop and achieve a reasonable sharing of reactive power. This study can be used as reference to thestudies of microgrid control.

关 键 词：微网 逆变器并联 功率均分 虚拟负阻抗 改进下垂控制 

分 类 号：TM464[电气工程—电器]