The Vector Control of Induction Machines with MRAS-Based Third-Order Sliding Mode Speed Observer

Abstract

The effectiveness of vector control depends heavily on the accurate estimation of rotor flux and speed. Among sensorless techniques, Model Reference Adaptive System (MRAS) are widely used due to its simplicity and low computational cost. This chapter presents an advanced vector control strategy for induction machines that combines a Third-Order Sliding Mode (TOSM) control scheme with a MRAS–based speed observer. The proposed MRAS-TOSM structure ensures precise and reliable rotor speed estimation under parameter uncertainties and varying operating conditions. By integrating third-order sliding mode control, the system exhibits enhanced robustness against disturbances and parameter variations (such as stator resistance and rotor inductance), fast convergence, and minimised estimation errors. Key performance metrics, including overshoot reduction, settling time, and steady-state accuracy, are analysed in detail through extensive simulation studies. The simulation results demonstrate that the proposed approach significantly improves dynamic performance, stability, and robustness compared to conventional control methods. The results also highlight its potential for high-performance industrial drive applications and practical implementations, making it a suitable solution for both academic research and real-world engineering systems.