A nonlinear robust controller for matrix converter fed induction motor drives

Matrix converter (MC) fed induction motor drive has more attractive advantages than conventional pulse width modulation (PWM) inverter drives for the absence of large DC-link capacitors, higher input power factor and energy regeneration capability. However, due to the direct conversion characteristic of matrix converter, the drive performance of induction motor is easy to be influenced by input voltage disturbances of the MC. A nonlinear robust auto disturbance rejection controller (ADRC) is applied to the MC fed induction motor drive system, taking the place of proportional-integral (PI) regulator. In the drive system, the effects of external disturbance and model uncertainty are estimated and compensated by ADRC. Using this controller, the anti-disturbance capability of the drive system under abnormal input voltage conditions can be enhanced. In addition, the dynamic drive performances of induction motor are also improved, such as fast responses of speed change and load torque change. Experiments have been carried out to analyze the drive system, and simulation results verify the effectiveness of the proposed controller.