Improving efficiency of SMC based IFOC drive for induction motor applying MRAS based adaptive loss model control

The electrical parameters of induction motors can be affected over time due to continuous operation and increasing motor temperature. Therefore, accurately estimating certain motor parameters is crucial to ensure that these values remain independent of the motor's operational temperature and lifespan. Additionally, optimizing motor energy consumption is essential for reducing electrical energy usage. This study introduces a novel adaptive loss model control (ALMC) approach, designed within the framework of a model reference adaptive system (MRAS), for an indirect field-oriented control (IFOC) drive system employing sliding mode control (SMC) strategies. Unlike conventional IFOC control method that maintains a constant rotor flux during operation stator current, the proposed ALMC-based method optimizes the stator current to minimize induction motor losses under startup and no-load conditions, thereby significantly improving motor efficiency. Furthermore, SMCs are designed to ensure precise tracking of stator dq currents and accurate motor speed regulation. Due to the sensitivity of the IFOC drive to changes in stator bandwidth, precise estimation of this parameter is crucial for improving the performance of the SMC-based IFOC system. To achieve this, an MRAS-based approach utilizing active and reactive powers is aimed at identifying the dynamic bandwidths of both stator and rotor components. Consequently, the ALMC method based on MRAS is applied to minimize the vulnerability of the loss model control strategy to variations in motor parameters. Simulation results demonstrate that the combination of SMC-based current and speed controllers with the proposed adaptive ALMC method not only ensures precise tracking of the stator current and motor speed but also significantly reduces induction motor losses under low-load and startup conditions. Moreover, this approach enables precise estimation of rotor and stator bandwidth.