变频调速结构接地点与中性点电压的最小化分析

Neutral-to-Ground Voltage Minimization in a PWN-Convertor Configuration

针对变频调速系统中存在电磁干扰的现象,运用空间矢量法对在脉冲宽度调制下的变频器产生电磁干扰的原因进行深度分析,获得高频共模电压在接地点与中性点之间的电路模型,给出了空间矢量分析的算法和结果,通过提高调制脉冲的质量,减少电磁干扰的强度。变频系统能够产生严重的电磁干扰,高频共模电压是变频调速系统中引起电磁干扰的主要因素之一,对系统安全运行影响很大。文中建立了基于系统的局部电路仿真模型,并进行了不同频率信号输入下的计算机仿真实验。

Frequency conversion system may produce serious electromagnetic interference , and the high frequency common mode voltage produced by power converters is a major cause for it ,which may exert a tremendous influence on the safe operation of the system. The paper sets up some local circuit simulation models based on the system, and the simulation results show the benefits of the new approach in the experiment of computer.