DSP Based Induction Motor Torque and Parameter Identification

Abstruct A practical induction motor torque and parameter measurement scheme is proposed without using any mechanical sensors. The torque and parameter calciulation 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 propcsed torque measurement scheme has the features of wide bandwidth and no need for mechanical sensors. Simulation and experimental results on a 5hp induction machine driven under various operating conditions are also given for verification.