Adaptive Damping Ratio Control Method of Buck Converter for the Marine Pulsed Power Loads

Based on the problems of instantaneous voltage drop and continuous disturbance of the output voltage of the interface converter caused by the periodic power steps of pulsed power loads (PPLs), an adaptive damping ratio control is proposed for Buck converter. This approach enables direct and precise adjustment of the output voltage's response performance through the damping ratio, while maintaining independence from control parameters and providing rejection of input voltage disturbances. The proposed control introduces a voltage loop-typed regulator to cover the time-varying input and the nonlinear saturation of duty ratio, and thus a single-input single-output (SISO) second-order system of the output voltage and its reference can be established. It transforms the control problem under uncertain load disturbances to the damping ratio control of the second-order system. Moreover, current sharing control is achieved for the supply structure of parallel Buck converters by the additional regulation of the duty cycles under the premise of having little effect on the performance of voltage regulation. Simulations and hardware-in-the-loop experiments demonstrate that the parallel converters can achieve fast and smooth voltage regulation and current sharing during different PPL transients. © 2024 Chinese Society for Electrical Engineering. All rights reserved.