Sensorless Control of Induction Motor using MSTOGI based Super Twisting Sliding Mode Flux Observer for Electric Vehicle

This paper presents second-order adaptive super twisting sliding mode observer (ST-SMO) based sensorless control for battery fed induction motor drive train. To reduce the cost, increase reliability and to ensure the continuity of operation, the mechanical sensor is replaced with ST-SMO for speed and position estimation. Unlike the classical SMO, ST -SMO uses a continuity function in the feedback to direct the sliding surface to zero, which reduces the chattering. Instead of pure integrator, the usage of mixed second and third-order generalised integrator (MSTOGI) followed by the ST-SMO, alleviates the problems of DC drift and lower order harmonics present in the measured quantities. Besides, it suppresses the chattering due to the low sampling frequency operation of ST - SMO. This observer is implemented with field oriented control for induction motor based electric drive train. The presented observer with the system is built-in MATLAB/Simulink software, and the effectiveness of the algorithm is validated for all the operating conditions.