级联H桥型逆变器载波移相正弦脉宽调制输出性能分析  

Characteristic Analysis of Carrier Phase-Shifted SPWM Output Voltage of Cascaded H-Bridge Converters

作　　者：吴连贵[1] 涂春鸣[1] 姜飞[1] 郭祺[1] 刘子维[1] 

机构地区：[1]国家电能变换与控制工程技术研究中心(湖南大学),湖南省长沙市410082

出　　处：《电网技术》2016年第7期2155-2161,共7页Power System Technology

基　　金：国家自然科学基金项目(51377051)~~

摘　　要：级联H桥逆变器能够显著提高器件的等效工作频率,降低补偿电压谐波畸变率。然而,单极性、双极性载波水平移相正弦脉宽调制(carrier phase-shifted sinusoidal pulse width modulation,CPS-SPWM)的输出性能与调制比关系密切。通过理论分析,得出了单极性、双极性CPS-SPWM的调制比与输出电平数的关系,阐明了双极性调制下,正负电平抵消原理;提出了特定补偿深度下,采用单极性、双极性CPS-SPWM时,输出期望电平数目的直流侧电压选择方法;通过PSCAD/EMTDC仿真软件搭建模型,验证了调制比与输出电平数分析的正确性以及直流侧电压选择方法的有效性。Cascaded H-bridge inverter can obviously improve equivalent working frequency and decrease harmonic distortion of compensation voltage. Close relationship exists between modulation ratio and output performance of inverter. Through theoretical analysis, relationships between output level number and modulation ratios for bipolar and unipolar CPS-SPWM（carrier phase-shifted SPWM） modulations are derived respectively. Positive-negative offset level principle is illustrated when bipolar CPS-SPWM is adopted. In addition, when bipolar or unipolar CPS-SPWM modulation is adopted, a dc-side voltage selection method based on expectation numbers of output level is presented under specific compensation degree. PSCAD/EMTDC simulation results confirm correctness of the analysis of modulation ratio and output levels and effectiveness of dc side voltage selection method.

关 键 词：动态电压恢复器 高压级联 载波移相 调制比 多电平 

分 类 号：TM72[电气工程—电力系统及自动化]