三电平LLC谐振变换器中点电压平衡控制方法  

Neutral Voltage Balancing Control Method for Three-level LLC Resonant Converter

作　　者：孔祥平 张弛 丁明敏 邓富金 KONG Xiang-ping;ZHANG Chi;DING Ming-min;DENG Fu-jin(Power Grid Technology Center State Grid Jiangsu Electric Power Company,Nanjing 211103,China;不详)

机构地区：[1]国网江苏省电力有限公司电力科学研究院,江苏南京211103 [2]东南大学电气工程学院,江苏南京210096

出　　处：《电力电子技术》2023年第5期126-129,共4页Power Electronics

基　　金：国网江苏省电力有限公司科技项目(J2021179)。

摘　　要：针对全桥二极管中性点箝位(NPC)三电平LLC谐振变换器的中点电压偏移问题,此处提出了一种基于五电平脉宽调制(5L-PWM)的中点电压平衡控制方法。首先介绍了5L-PWM策略下变换器工作原理,并分析了不同工作模式下对中点电压的影响;之后提出了根据中点电压偏移情况选择合适工作模式的中点电压平衡控制方法,该方法无需比例积分(PI)控制器,同时在中点电压调节过程中不会造成功率传输波动。最后通过仿真和实验验证了所提控制方法可以有效解决中点电压的偏移问题。Aiming at the neutral voltage offset problem of the full-bridge diode neutral point clamp(NPC)three-level LLC resonant converter,a neutral voltage balancing control method based on five-level pulse width modulation(5LPWM)is proposed.Firstly,the working principle of the converter under the 5L-PWM strategy is introduced,and the influence of different operating modes on the neutral voltage is analyzed.Then,a neutral voltage balancing control method that selects the appropriate working mode according to the neutral voltage offset is proposed,which does not require a proportional integral(PI)controller and does not cause power transmission fluctuations during the neutral voltage adjustment process.Finally,simulation and experiment are used to verify that the proposed control method can solve the neutral voltage offset problem effectively.

关 键 词：谐振变换器 三电平 中点电压平衡 

分 类 号：TM46[电气工程—电器]