Experimental Comparison of Discrete Time Sliding Mode and Conventional, PI Current Controllers for IM Drives

An approach to discrete-time sliding-mode (SM) current control and conventional SM with smoothing filter is presented for field-oriented induction motor (IM) drives. Design of both proposed SM controllers is based on space vector PWM scheme by introducing some parts of the stator model as control input, which may correspond to voltage vector command. The control input was obtained employing the error between measured and reference currents of the stator. In order to compare the performance of proposed two SM current controllers with each other and with a conventional PI controller, they were simulated and also experimentally implemented for the indirect field oriented drives of an IM. The results verified to validity of proposed both SM current controllers and superiority of discrete time SM controller to conventional PI controller and SM with low pass filter (LPF)