Robust scheme for maximum torque control of induction motors

A new robust torque control algorithm for induction motors is suggested to obtain high performance as well as high efficiency, under direct torque control scheme. This algorithm has two stages. In the first stage maximum torque is achieved with optimal currents and voltages for any given speed, resulting in high efficiency. In the second stage, in the steady state, the controller corrects itself for stator resistance variations, thereby achieving robustness in the control scheme. The direct torque control implementation eliminates the need for vector transformations and results in a quick response making it suitable for a wide variety of applications such as electric vehicles (EYs). Simulation results show the performance of the proposed robust torque control scheme in response to high-speed demands and stator resistance variations.