不平衡情况下基于新型正负序分量检测的多电平逆变器控制策略  

Control strategy of multi-level inverter based on a new method for detecting positive and negative sequence components under unbalanced grid voltage conditions

作　　者：谢云至 汪可友[1] 李国杰[1] 黎建 

机构地区：[1]电力传输与功率变换控制教育部重点实验室,上海交通大学电气工程系,上海200240 [2]国电云南电力有限公司,云南昆明650021

出　　处：《电力系统保护与控制》2014年第9期74-80,共7页Power System Protection and Control

基　　金：国家高技术研究发展863计划(2012AA050204);国家国际科技合作合作专项(2013DFG71630)~~

摘　　要：电网电压不平衡情况下的系统控制策略是大规模光伏系统并网运行需要解决的关键问题之一。分析了电网电压不平衡情况下光伏系统的输出功率流,在此基础上推导出并网电流参考指令。提出一种新的检测正序、负序分量的方法—模值检测法,该方法基于电网电压矢量的模值和正序、负序矢量的模值之间的数学关系,在αβ坐标系下实现了电网电压正序、负序分量的检测。该方法具有几何概念清晰、计算量小的优点。最后在电网不平衡情况下对系统控制方案进行了仿真验证,仿真结果验证了提出方法的有效性。Control strategy under unbalanced grid voltage conditions is one of the most important issues for grid integration of high penetration photovoltaic （PV） systems. The output power flow of PV systems is analyzed and the reference instruction of grid-connected current is deduced. Module value detection method is developed, which is a new method for detecting the positive and negative sequence components. The method realizes the detection of the positive and negative sequence components in aft coordination based on mathematical relationship between the module value of the space vector and that of the positive sequence vector and negative sequence vector. It has the advantages of clear geometrical concept and low calculation cost. Finally, the simulation is carried out under the unbalanced grid voltage conditions. The simulation results verify the effectiveness of the proposed method.

关 键 词：多电平逆变器 不平衡电网电压 正序分量 负序分量 并网控制 

分 类 号：TM464[电气工程—电器]