Second order sliding mode observer of linear induction motor

This study proposes a second-order sliding-mode observer (SOSMO) of the linear induction motor to deal with the sensorless problem, considering the influence of the end effects. The proposed SOSMO required only the measured voltages and currents to provide flux, motor speed and speed-depended parameter estimation simultaneously. The stability of the system and the error convergence of the flux and the speed have been proved. The performance of the proposed observer is verified by hardware-in-the-loop test system. Furthermore, a comparative study with model reference adaptive system and Luenberger observer is presented.