Voltage angle direct torque control of induction machine in field-weakening regime

This study presents a novel algorithm for the induction motor torque control in field-weakening region. The proposed method insures maximum DC bus utilisation and extends the torque-speed curve up to the system limits. Controller is based on the stator voltage angle control. It provides full DC-link disturbance rejection and offers the torque response time sufficient for most applications. The algorithm is simple, without neither the outer flux loop nor the inner current loop. Dynamic response is preserved over wide speed range by means of gain-scheduling. Simulations and experiments prove an ease of implementation and the robustness of the proposed solution. This study comprises analytical considerations, simulation results, a detailed description of implementation steps and extensive experimental results.