基于MRAS的无速度传感器异步电机DTC系统

Speed-Sensorless Direct Torque Control of an Induction Motor based on MRAS

对一类实用的基于模型参考自适应(ModelReferenceAdaptiveSystem,简称MRAS)方法的无速度传感器直接转矩控制(DirectTorgueControl,简称DTC)系统进行了研究,以提高系统的耐用性并降低成本。采用具有补偿信号的改进积分器提高了参考模型的准确性,同时利用新的转子磁链计算模型代替电流模型作为系统的可调模型,以避免难以测量转子侧参数,从而提高速度的辨识精度,在较宽的速度调节范围内改善异步电机无速度传感器控制性能。在DSP电机控制系统开发平台上实现了无速度传感器直接转矩数字控制系统。实验得到了较为理想的结果,验证了系统设计方案的可行性。

To improve the robustness of the system and reduce the cost,a kind of practical speed-sensorless Direct Torque Control（DTC） system based on Model Reference Adaptive System （MRAS） method is proposed in this paper.The accuracy of the reference model is improved by a modified integrator with compensation signal.The adjustable model is replaced by a novel computation model of rotor flux to avoid the measurement of the rotor parameters.Consequently, better accuracy of speed estimator is obtained and the control performance of speed sensor-less DTC system is improved over wide range.The proposed system is realized in the DSP develop platform of motor control,and the validity of the proposed system is proved in the experiments.