级联H桥光伏并网逆变器过调制控制策略  

Study on Overmodulation Control Strategy of Cascaded H-bridge Photovoltaic Grid-connected Inverter

作　　者：陈威 CHEN Wei(School of Electrical and Information Engineering,Anhui University of Science and Technology,Huainan Anhui 232001,China)

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：《兰州工业学院学报》2024年第1期56-63,共8页Journal of Lanzhou Institute of Technology

摘　　要：针对THCS无法应对模块间输入功率严重不平衡时导致过调制单元调制度大于1.155的问题,在THCS的基础上提出了一种光伏并网逆变器过调制控制策略。仿真结果表明:相同光照条件下,采用THCS控制时由于光伏组件输出功率差异较大,超出其线性调制范围(1.155),并网电流发生畸变THD值为10.6%;而采用过调制控制策略,即使H桥单元调制度大于1.155,依然能够使系统避免发生过调制,并网电流THD值为2.03%,电流质量改善效果较为显著。Aiming at the problem that THCS can not cope with the serious imbalance of input power between modules,which leads to the overmodulation unit regulation greater than 1.155,an overmodulation control strategy for grid-connected PV inverters is proposed based on THCS.The simulation results show that under the same illumination condition,the THD value of grid-connected current is 10.6%because the output power of PV module is different greatly when THCS control is used,which exceeds the linear modulation range(1.155).However,the overmodulation control strategy can avoid overmodulation even if the H-bridge unit modulation system is greater than 1.155,and the THD value of grid-connected current is 2.03%,and the current quality improvement effect is significant.

关 键 词：级联H桥 功率不平衡 调制波幅值 三次谐波补偿 过调制 

分 类 号：TM464[电气工程—电器]