Robust Control of Induction Motor Drives Using Prediction and Estimation of DC Link Capacitor Voltage

This study presents a modified control method for induction motor drives powered by a three-phase four-switch inverter. The objective is to enhance the robustness of inverters in controlling induction motors by replacing the six-switch inverter with a four-switch inverter equipped with a DC link capacitor, due to the absence of one of the legs. A novel switching method is introduced based on minimizing the effects of the capacitor voltage on the system. The switching method in the four-switch inverter is similar to space vector modulation, with the difference that the selection of active vectors and the adjustment of switching times are performed in such a way that, in addition to tracking the reference voltage, the impact of capacitor voltage fluctuations on the system is reduced. This enhances the capability of the motor and inverter under atypical operating conditions. The result of refining the switching methods is a reduction in flux and torque ripples and improved inverter performance. To evaluate and validate the proposed method, simulation results in the MATLAB environment are presented.

کلیدواژه ها:

Induction Motor Drives ، DC Link Capacitor Voltage Fluctuations ، Robust Control of Frequency Inverters