Soft Starting of Induction Motor With Torque Control

This paper presents a simple technique based on stator-flux estimation to control the electromagnetic torque of induction motors (IMs) during soft starting. The inherent problems related to pure integration of the back electromagnetic force to estimate the stator flux are minimized using the low-pass-filter approach. The experimental results are dealt with and compared with the usual current-control technique. The results obtained validate the proposed technique, showing its viability in applications where the objective is to fit the IM torque profile during starting or stopping according to the load torque.