Abstract:Based on disturbance observer theory (DOB), combining the characteristic of PWM voltage source inverter (VSI), a new control strategy is proposed for the inverter and the add-on DOB controller is designed. The add-on DOB controller is used as a compensator to the conventional double loop feedback inverter control system, so that the inverter can achieve fast dynamic response and improve disturbance rejection performance. The add-on DOB controller is easy to apply in the actual projects for the simple structure and short calculation time while implementing in the digital control system. Moreover, none of new sample signals are needed. The conventional control system and the new control system are compared. Experiments are carried out on a PWM inverter control system based on DSP MC56F8323. The results are provided to verify and confirm the practical efficiency of the proposed approach.
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