Magnetic flux compensating torque control method suitable for general purpose inverters with superaudible switching frequencies

The new torque control method described is suitable for general-purpose induction motor variable-speed drives driven by superaudible frequency pulse-width modulation (PWM) inverters. The primary magnetic flux reference is compensated, using only current sensors, on the basis of the inverter angular frequency and the slip angular frequency so that motor torque can be generated according to load torque. The super audible frequency PWM signals are generated by divisions of duration times of the voltage vectors, determined on the basis of the primary magnetic flux reference. Experiments show that high-performance torque characteristics suitable for general-purpose inverters can be obtained by this method