一种高效光伏逆变器的PWM策略  

A PWM Strategy for High EfficiencyPhotovoltaic Inverter

作　　者：龚仁喜[1,2] 林宇航 GONG Ren-xi;LIN Yu-hang(Guangxi University,Nanning 530000,China)

机构地区：[1]广西大学,电气工程学院,广西南宁530000 [2]南宁学院,交通运输学院,广西南宁530000

出　　处：《电力电子技术》2023年第6期130-133,共4页Power Electronics

基　　金：国家自然科学基金(61561007)。

摘　　要：光伏(PV)逆变器正朝着更高效、更高功率密度的方向发展。此处针对目前PV逆变器输出效率较低、功率密度较小的问题,提出了一种提高PV逆变器效率的脉宽调制(PWM)策略。该调制策略工作原理如下:采用调制波分层、分区域的正弦脉宽调制(SPWM)方式,获取输出五电平电压的开通关断信号,使其两个开关桥臂分别工作在高频和低频的状态,来减少低频开关桥臂的损耗,进而实现对传输效率的提高。此处选用T-NPC作为PV逆变器的逆变拓扑,对所提调制策略进行实验验证与对比分析,实验结果表明,所提PWM策略可以有效提高T-NPC型PV逆变器的传输效率,进而获得更高的功率密度。Photovoltaic(PV)inverters are moving towards greater eficiency and higher power density.A pulse width modulation(PWM)strategy to improve the efficiency of PV inverters is proposed to solve the problem of low output efficiency and low power density of PV inverters.The modulation strategy works as follows:the sinusoidal pulse width modulation(SPWM)method of modulating waveform in layers and regions is used to obtain the turn-on and turn-off signals of the output five-level voltage,so that the two switching bridge arms work at high and low frequencies respectively to reduce the loss of the low-frequency switching bridge arms and thus achieve the improvement of the transmission efficiency.T-NPC is chosen as the inverter topology of PV inverter,and the proposed modulation strategy is experimentally verified and comparatively analyzed.The experimental results show that the proposed PwM strategy can effectively improve the transmission efficiency of T-NPC PV inverter,and then obtain higher power density.

关 键 词：光伏逆变器 脉宽调制 逆变拓扑 传输效率 

分 类 号：TM464[电气工程—电器]