A robust high order sliding mode for buck-boost converters with large disturbances

During the process of renewable energy power generation, the frequently intermittent input and load disturbance require power converters of stronger robustness. The traditional sliding mode controller (SMC) has inevitable chattering phenomenon due to its discrete control law. In order to solve the above problems, this paper designed an avoidance chattering and strong robust converter based on the high order sliding mode control (HOSMC). The digital signal processor (DSP) TMS320F28035 was used as the core chip. To solve the intermittent disturbance in the random renewable energy power generation, this paper studied on the dynamic features and stability of the converter controlled by a HOSM algorithm "super-twisting". And the effectiveness was illustrated through the experiments compared with the PI controllers. The experimental results show that, under the large disturbances in output, the converter controlled by the super-twisting sliding mode has stronger robustness and higher precision; The same situation also appeared under the large disturbances in input.