DSP based induction motor torque and parameter identification

A practical induction motor torque and parameter measurement scheme is proposed without using any mechanical sensors. The torque and parameter calculation is performed by a digital signal processor (DSP) based on measured motor terminal waveforms. Since the motor parameters are required for torque calculation, a novel scheme is developed for parameter identification. The motor parameters can be extracted from the measured motor current and motor voltage when the motor-fed by inverters, AC voltage controllers or other equipment-is started under no load conditions. The proposed torque measurement scheme has the features of wide bandwidth and no need for mechanical sensors. Simulation and experimental results on a 5 hp induction machine driven under various operating conditions are also given for verification