Speed control of induction motor without rotational transducers

This paper describes a newly developed speed sensorless induction motor drive control scheme based on neural network techniques. The backpropagation neural network technique is used to provide a real-time adaptive identification of the motor speed. The estimation objective is defined in terms of a desired or target trajectory that the neural networks model output should match or trade as closely as possible. The backpropagation algorithm is used to adjust the motor speed so that the neural model output follows the target trajectory. This backpropagation mechanism forces the estimated speed to follow precisely the actual motor speed. The zero speed crossing phenomena is also described and experimental results are presented and analysed.