Novel suppression control strategy of disturbance from the input voltage source in DC/DC converters

DC/DC converters have been widely used in industrial and commercial applications nowadays. Abrupt jumps in the input voltage of a DC/DC converter can lead to severe excursion of its output voltage, no matter how well its feedback controller is designed to suppress such disturbance due to the feedback mechanism. Predictive compensation can achieve improved disturbance rejection and tracking performance in those scenarios, resulting in a two-degree-of-freedom design. It is a challenge to design the feedforward controllers, due to the internal parameters change of the converter caused by aging or different operating conditions, even the load ifself is part of the converter dynamics. An adaptive feedforward compensation design integrating system identification with the feedforward compensator is proposed in this paper. Based on boost DC/DC converter, combined feedback and adaptive feedforward design is investigated. The results show that the two-degree-of-freedom design leads to much improved performance in disturbance rejection from the input voltage sources. System performance deteriorates significantly following the change of converter parameters, making adaptation mandatory. An adaptive scheme for updating the feedforward controller reveals to be necessary and with the ability to restore desired system performance.