A new speed observer for control system of induction motor

A new speed observer for control system of induction motor is proposed in the paper. Disturbances are defined, estimated and used in the observer instead of products of rotor angular velocity and rotor flux vector components. The disturbances and rotor flux vector components are used to calculate the rotor angular velocity. Very low errors between the estimated and real rotor angular velocity in steady states and transients have been observed in the new observer for values very close or equal to zero. Properties of the control system with new speed observer have been investigated and results of simulations are presented.