死区对电压型逆变器输出误差的影响及其补偿

Dead-Time Influence on Output Error of Voltage Source Inverter and Compensation

针对电压型逆变器的死区效应,分析了死区对逆变器输出电压谐波和电流的影响,提出一种基于功率导通时间实时检测的死区补偿和电机相电压检测方法。为避免电流过零点的直接检测或间接预估,设计硬件电路直接检测功率管的导通时间,得到逆变器的实际死区时间,并在软件中进行补偿,同时得到电机实际的相电压。采用该方法得到的死区时间反映了开关器件导通和关断时间受结温和导通电流影响的特性,最后对上述方法进行了实验验证。

Aimed at dead-time effect of voltage source inverter, the dead-time influence on output voltage harmonics and current of inverter is analyzed and a novel dead-time compensation and phase-voltage measurement method based on turn-on time of the power tube real-time measurement is presented in this paper. To avoid the currents zero-crossing detection or estimation, the circuits are designed for directly measuring the power tube turn-on time. The actual dead-time of inverter is achieved, and the dead-time is compensated in software program. At the same time, the actual phase-voltage of motors can be obtained. The characteristic of power device turn-on time and turn-off time are influenced by the junction temperature and collector current is reflected by the obtained dead-time using this method. In the end, the proposed method is verified by experiment.