Sliding Mode Control of Parallel DC/DC Converters

In this paper, taking the typical buck type in paralleled DC/DC converter as an example, a mathematical model of the parallel buck converter is established in the continuous domain, and a sliding mode control (SMC) system based on the master-slave control is designed for improving the output performance of the paralleled system. In order to adapt to practical engineering applications, the SMC system is further discretized by the zero-order holder (ZOH) to obtain the corresponding discrete control system, and the constraint conditions of the sampling period of the discretized SMC system for the paralleled buck converter is derived by analyzing the sufficient stable conditions of the discrete SMC system. Finally, the influence of discrete controller parameters and the superior performance of the designed controller on the SMC system is further discussed and verified by simulations.