一种调控三电平NPC逆变器中点电压平衡的不对称PWM策略  

Asymmetric PWM method to obtain balanced NP voltage in a three-level neutral-point-clamped converter

作　　者：李锐[1] 郑中祥[1] 魏华[1] 吴浩伟[1] 陈涛[1] Li Rui;Zheng Zhongxiang;Wei Hua;Wu Haowei;Chen Tao(Wuhan Second Ship Design and Research Institute,Wuhan 430205,China)

机构地区：[1]武汉第二船舶设计研究所,武汉430205

出　　处：《船电技术》2022年第8期1-6,共6页Marine Electric & Electronic Engineering

基　　金：海洋核动力平台技术、装备研制及示范应用(2017YFC0307800)。

摘　　要：三电平NPC中点电压不平衡会带来开关管电压应力增加、输出电压电流波形畸变等问题。本文通过建立NPC的受控源模型详细分析了中点电压不平衡对输出电压电流波形影响,在此基础上提出了一种新的不对称SPWM(ASPWM)方案。该方案根据中点电压的波动大小调整正负调制波的直流偏置和幅值,从而消除中点电压波动对输出电压电流的影响。最后通过RT-LABshi实时仿真试验验证了该方案的有效性。The NP imbalance will increase voltage stress of power switches and bring distortion of output voltages and currents. This paper establishes controlled source model of three phase NPC inverter and discusses the NP imbalance effects on the output voltages and currents. Then a new asymmetric PWM method(ASPWM)has been proposed. This method can eliminate the impact on the output voltages and currents by adjusting the modulation wave amplitude and DC bias according to the NP imbalance. This paper gives the real time simulation of the three-phase NPC inverter and the results verified the model and analysis.

关 键 词：三相三电平NPC 中点平衡 受控源模型 PWM策略 

分 类 号：TM464[电气工程—电器]