适用于三电平逆变器低调制比区域的双极性载波脉宽调制策略研究  

Research on Bipolar Carrier-based PWM Strategy Suitable for Low Modulation Index Region of Three-level Inverter

作　　者：高瞻 王立欣 周志达 耿程飞 吴轩钦 GAO Zhan;WANG Lixin;ZHOU Zhida;GENG Chengfei;WU Xuanqin(Harbin Institute of Technology Shenzhen,Nanshan District,Shenzhen 518055,China;Shenzhen INVT Electric Co.,Ltd.,Guangming District,Shenzhen 518106,China)

机构地区：[1]哈尔滨工业大学(深圳),深圳市南山区518055 [2]深圳市英威腾电气股份有限公司,深圳市光明区518106

出　　处：《中国电机工程学报》2023年第18期7254-7267,共14页Proceedings of the CSEE

摘　　要：当三电平逆变器工作在低调制比区域时,窄脉冲对输出电压的畸变影响尤其显著,甚至会导致逆变器运行不可控,而传统空间矢量脉宽调制策略(space vector PWM,SVPWM)在低调制比区域存在窄脉冲。针对以上问题,该文首先分析传统SVPWM产生窄脉冲的原因,然后设计可抑制窄脉冲的双极性SVPWM。在此基础上,为更方便的实现双极性SVPWM,推导双极性SVPWM的等效双调制波表达式。通过制定双调制波与三角载波的比较规则,进一步提出双极性载波脉宽调制策略(bipolar carrier-based PWM,BCBPWM),并为其设计中点电压平衡控制和死区补偿方法。最后,分析BCBPWM的脉宽特性、中点电压波动、谐波性能和直流电压利用率。仿真和实验结果证明,相较传统SVPWM,BCBPWM可在低调制比区域完全消除窄脉冲、提升电流谐波性能,其可以控制中点电压平衡并具备计算简单、实现方便的优势。When the three-level inverter operates in the low modulation index region,the distortion of output voltage caused by narrow pulse is particularly significant,and even makes the inverter operation uncontrollable.However,the traditional space vector PWM(SVPWM)strategy has narrow pulse in the low modulation index region.To solve the above problems,this paper first analyzes the causes of narrow pulse in traditional SVPWM,and then designs the bipolar SVPWM which can eliminate narrow pulse in the low modulation index region.On this basis,in order to implement bipolar SVPWM more conveniently,the equivalent double modulation wave of bipolar SVPWM is deduced.By formulating the comparison rules between double modulation wave and triangular carrier,the bipolar carrier-based PWM(BCBPWM)strategy is further proposed.In addition,the neutral-point voltage balance control and dead time compensation method are designed for BCBPWM.Finally,the pulse width characteristics,neutral-point voltage fluctuation,harmonic performance,and DC voltage utilization of BCBPWM are analyzed.Simulation and experimental results prove that compared with traditional SVPWM,BCBPWM can eliminate narrow pulse completely and improve current harmonic performance in the low modulation index region.It can control the neutral-point voltage balance,and has the advantages of simple calculation and convenient implementation.

关 键 词：三电平逆变器 窄脉冲 低调制比区域 双极性载波脉宽调制 中点电压平衡控制 死区补偿 

分 类 号：TM464[电气工程—电器]