RFNN controlled sensorless induction spindle motor drive

A sensorless induction spindle motor drive using synchronous PWM (SPWM) and dead-time compensator with recurrent fuzzy-neural network (RFNN) speed controller is proposed in this study for advanced spindle motor applications. First, the operating principles of a new type SPWM technique and the circuit of dead-time compensator using field-programmable gate arrays (FPGA) are described. Then, a speed observer based on a modified Luenberger observer is adopted to estimate the rotor speed. Moreover, since the control characteristics and motor parameters for a high-speed induction spindle motor drive are time-varying, an RFNN speed controller is developed to reduce the influence of parameter uncertainties and external disturbances. In addition, the RFNN is trained on-line using a delta adaptation law. Finally, the performance of the proposed sensorless induction spindle motor drive system is demonstrated using some simulated and experimental results.