模块化多电平逆变器的改进型PS-SPWM研究  

Research of Improved PS-SPWM on Modular Multilevel Converter

作　　者：王辉[1] 张宁敏 

机构地区：[1]湖南大学电力推进与伺服传动教育部重点实验室,长沙410082

出　　处：《控制工程》2014年第6期797-801,共5页Control Engineering of China

基　　金：国家国际科技合作专项(2011DFA62240);国家973计划资助项目(2010CB736201)

摘　　要：模块化多电平换流器(MMC)具有级联型多电平换流器"模块化"的优点,输出电压中的谐波含量少,在高压直流输电中具有巨大的应用潜力。介绍MMC的数学模型和工作原理,分析传统载波移相调制策略,针对其存在的缺点提出一种改进型载波移相PS-SPWM调制算法,即载波三角波移相-开关频率优化PWM法(PS-SFO-PWM),并与载波移相SPWM调制算法进行比较;针对MMC中特有的三相之间的环流问题,通过对其进行PI调节,使环流抑制在一定的范围内,利于功率的有效传输。最后,在Matlab/Simulink7.0环境下搭建了基于载波三角波移相-开关频率优化PWM法的5电平逆变器的仿真模型,仿真结果验证了所提方法具有直流电压利用率高、开关频率小等优点。Modular multilevel converter has ＂modular＂ advantages like cascade type multilevel inverter, low harmonic content in output voltage and has great application potential in high voltage dc transmission, this paper introduces the mathematical model of MMC and working principle simply, analyzes traditional carrier phase-shifting modulation strategy. In view of its disadvantages, this paper puts forward a improved carrier phase SPWM, the carrier triangle wave phase - switching frequency optimized PWM method （PS-SFOPWM）, and compares with carrier phase SPWM modulation algorithm. For the circulation problem between the three phase of MMC, this paper carries on the PI adjustment way, which makes the circulation restrain in a certain range, conducive to the effective transmission of pow- er. Finally, in Matlab/Simulink environment builds 5-level inverter simulation system, based on the carrier and triangle wave phase shift- switching frequency optimized PWM method. The simulation results demonstrate that the proposed method has the advantages such as higher utilization rate of dc voltage, smaller switch frequency.

关 键 词：模块化多电平换流器 子模块 PS-SFOPWM 5电平逆变器 

分 类 号：TM46[电气工程—电器]