三电平Z源逆变器SPWM调制策略的研究

传统逆变器上下桥臂直通时会造成逆变器短路,为避免这一情况通常需要在逆变器控制信号中引入死区,进而造成逆变系统安全性下降输出谐波含量增加。Z源逆变器成功地克服了传统逆变器的缺陷和不足。Z源三电平逆变器有效地结合了Z源网络特性与传统三电平逆变器的优点。文章通过分析Z源三电平逆变器的工作原理,结合传统三电平逆变器的PWM控制策略,分别研究了适于Z源三电平逆变器控制的改进载波同相层叠调制、改进载波反相层叠调制和三次谐波注入载波同相层叠载波调制。仿真结果验证了三种调制策略的可行性。

Study of three level ZSinverterSSPWMSmodulation strategy

ZSsource inverterSdue to theSdirectSimplementation ofSthe lower bridge arm,Sto avoid theSdead zoneSis introduced,ScanSimprove the safety of inverter system,Sreduce the harmonicScontent ofSoutput of theSinverter andSbecome a hotSresearch.SBy introducing the Z sourceSnetworkSin front ofSthe traditionalSthree level inverter,SaSZSthree level inverter.SBased on theSworking principle of singleSZ sourceSthree level inverter,SSPWM modulation strategySwith reference to the traditionalSthree level,Ssimple boostScontrol principleSof Z source inverter,Swere studied. TheSimproved carrier phase disposition andSimprovedSbyScascadingStwoScarrierSsine modulation method,Sthe simulation experimentSand theScorrespondingSto validate theStwo modulationSstrategy.