全速域异步电动机的改进型直接转矩控制

Improved Direct Torque Control for Asynchronous Motor in All Speed Range

为了克服直接转矩控制在低速区的种种不足,改进型直接转矩控制被应用到大功率牵引传动系统的低速区。本文介绍了改进型直接转矩控制的基本原理,加入弱磁控制算法,同时采用一种适合工程应用的空间电压矢量PWM(SVPWM)过调制算法,将改进型直接转矩控制扩展到全速度范围。通过对此方案的实验验证,表明全速度范围异步电机转矩控制方案是可行的,系统具有良好的动静态性能,在具有较高开关频率的中小功率应用场合有着非常好的应用前景。

In order to overcome the disadvantages of direct torque control in the low speed range, improved direct torque control（IDTC） is applied to the low speed range of the high power traction driving system. The principle of IDTC and the field-weakening method are introduced. The space voltage vector PWM（SVPWM） overmodulation method suiting is adopted. IDTC is extended to the whole speed range. This scheme is proved by experiments. The experiments show that the IDTC scheme for the whole speed range of the asynchronous motor is viable and has good dynamic and steady state performance, which has good prospects in the middle and small power applications at high switching frequencies.