一种新颖的死区补偿和电机相电压检测方法

针对电压型逆变器的死区效应,提出了一种基于功率导通时间实时检测的死区补偿方法.为避免电流过零点的直接检测或间接预估,设计由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,并利用软件进行补偿,同时也可得到电机实际的相电压.采用该方法得到的死区时间反映出开关器件导通和关断时间受结温和导通电流影响的特性.实验结果表明,该方法能够有效地抑制电流谐波,使0,5,7次谐波降低了50%,改善了电流波形质量.

A Novel Dead-time Compensation and Motor Phase-voltage Measurement Method

Aimed at the dead-time effect of voltage-fed inverter,a novel dead-time compensation method based on turn-on time of the power tube real-time measurement has been presented in this paper.To avoid the currents zero-crossing detection or estimation,the circuits have been designed for directly measuring the power tube turn-on time.The actual dead-time of inverter has been achieved,and the dead-time has been compensated in software program.At the same time,the actual phase-voltage of motors can be obtained.The characters 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.It has been showed by the experimental results that the current harmonic has been rejected(the DC,5th and 7th harmonics have been reduced 50%),and the current wave has been effectively improved.