基于等效阻抗的逆变器并联与环流抑制研究  

Research on Parallel Connection and Circulating Current Suppression of Inverters Based on Equivalent Impedance

作　　者：杨帅帅 卢子广[1] 宫萍萍[1] YANG Shuai-shuai;LU Zi-guang;GONG Ping-ping(Guangxi Uinversity,Nanning 530004,China)

机构地区：[1]广西大学,电气工程学院,广西南宁530004

出　　处：《电力电子技术》2021年第7期64-67,共4页Power Electronics

摘　　要：低压孤岛微电网系统中,由于线路呈阻性,应用传统下垂控制往往存在功率耦合,当含有本地负荷时传统控制策略更加难以实现功率均分以及环流抑制。对此,此处提出了一种等效虚拟阻抗的逆变器并联控制策略以降低线路阻抗和本地负载不相等时引起的无功功率均分误差。首先分析环流和功率特性,得出端电压和线路阻抗与无功功率和环流之间的关系,基于等效阻抗计算方法对本地负荷和线路阻抗等效计算,根据等效阻抗设计虚拟复阻抗实现功率解耦控制。同时对传统下垂控制引起的电压跌落问题加入线路阻抗电压以及电流偏差补偿控制策略,缓解功率均分和端电压降落之间的内在矛盾。实验验证了该方法的有效性。Low-voltage isolated island microgrid system,because the line is resistive,the traditional droop control often has power coupling,and it is difficult to realize power sharing and circulation suppression in the tarditional control strategy with local load.In order to solve the problems,a control strategy for parallel inverters with equivalent virtual impedance is proposed to reduce the reactive power error caused by unequal line impedance and local load.Obtained by analyzing the characteristics of circulating current and power,the local load and the line impedance are equivalently calculated based on the equivalent impedance calculation method,and the virtual complex impedance is redesigned according to the calculation result and realize power decoupling control,realize power decoupling control.At the same time,in order to solve the problem of voltage sag caused by traditional control,the control strategy of line impedance voltage and current deviation compensation is added,the inherent contradiction between power equalization and terminal voltage drop can be effectively alleviated.Experimental results verify the feasibility of the method.

关 键 词：逆变器 环流抑制 等效虚拟阻抗 

分 类 号：TM464[电气工程—电器]