摘要
在介绍三电平逆变器基础上,研究了三电平逆变器空间电压矢量(space vector pulse widthmodulation,SVPWM)控制,分析了三电平逆变器电压矢量分布情况和直流侧电容中点电位偏移原因。根据SVPWM控制规律,提出了一种基于矢量合成抑制中点电位偏移的SVPWM方法:利用合成矢量在采用周期内向中点注入电流为零,实现中点电位平衡。通过仿真分析,验证了抑制中点电位偏移控制策略的实用性和可行性。实验证明,三电平逆变器中点电位偏移能够被有效抑制,并且具有输出谐波含量低、输出波形好的特性,适合应用于高压大功率变流系统。
The SVPWM control strategy is researched on the based of the circuit structure of three-level inverter. The distribution of the space voltage vector and the reason of neutral-point shift are analyzed.Then,a new modulation approach is introduced,which is based on the vector synthesis.And it can guarantee the entire balance of the neutralpoint voltage,The simulation results confirm that the strategy is practicable and feasible.Neutral-point shift in threelevel inverter is effectively inhibited,the output harmonic content is low,and output line-voltage has a good quality. Three-level inverter is suitable for high-voltage and high-power inverter system.
出处
《机电一体化》
2010年第9期21-26,共6页
Mechatronics
