Current error space vector based constant switching frequency hysteresis controller for VSI fed Induction Motor drives

A current error space vector based hysteresis controller for two-level voltage source inverter fed Induction Motor drives is proposed in this paper. All inherent advantages of conventional hysteresis controllers like fast dynamic response, simple implementation, switching in one phase at a time etc. are also retained in the proposed controller . The harmonic spectrum of phase voltage obtained using proposed controller is similar to that of constant switching frequency bus clamping space vector pulse width modulated voltage source inverter. In this proposed controller hysteresis boundary is computed online using estimated stator voltages along α and β axes. The current errors along alpha and beta axes and steady state model of induction motor are used for the estimation of stator voltages along α and β axes. Hysteresis boundary is computed and using that the vector selection logic is deduced in such a way that the vector switching pattern is exactly similar to that of bus clamping SVPWM technique. Extensive simulation of the proposed hysteresis controller based inverter fed drive scheme is carried out using SIMULINK toolbox of MATLAB for steady state performance.