微网孤岛模式下负荷分配的改进控制策略  

An Improved Control Strategy of Load Distribution in an Autonomous Microgrid

作　　者：李福东[1] 吴敏[1] 

机构地区：[1]中南大学信息科学与工程学院,湖南省长沙市410083

出　　处：《中国电机工程学报》2011年第13期18-25,共8页Proceedings of the CSEE

基　　金：国家自然科学基金项目(60974045);国家杰出青年科学基金(60425310)~~

摘　　要：以含多个分布式电源的微网为研究对象,提出一种微网孤岛运行模式下的负荷分配改进控制策略。针对传统V/f下垂特性控制方法的不足,基于V/δ下垂特性控制的思想,增加了P-δ下垂控制修正项和Q-V下垂控制修正项,有效跟踪功率变化的动态特性,优化了微网内部的负荷分配。同时,设计了辅助控制器,对每个逆变器参考电压的d轴分量进行修正,并采用高的P-δ下垂控制因子,可有效防止系统在微网内负荷或电源显著变化时发生震荡,并能确保合理的负荷分配。对孤岛模式下不同的系统状态进行仿真和对比分析,验证所提出的控制策略的有效性。This paper proposed an improved control strategy of load distribution in an autonomous microgrid with multiple distributed generation units. Load sharing in an autonomous microgrid based improved V /δ droop control, instead of commonly used V / f droop control method, was investigated in this paper. The P-δ droop function and Q-V droop function employs additional derivative terms with modified gain respectively, which guarantee stability and good transient response. A supplementary loop was proposed around the primary droop control loop of each distribution generator （DG） converter which can modulate the d-axis voltage reference of each converter as to stabilize the system despite having high gains that are required for better load sharing. The simulation results verify that the proposed control strategy is effective for load distribution in the autonomous microgrid.

关 键 词：分布式发电 微网 V /δ控制 辅助控制器 孤岛模式 负荷分配 

分 类 号：TM76[电气工程—电力系统及自动化]