PV Constant Voltage Control Strategy Based on Super-Twisting Sliding Mode Control

The control strategy of photovoltaic (PV) system in DC Microgrid affects the overall microgrid stability performance. When there is excess power in the microgrid, the power generated by the PV system needs to be reduced and the PV system needs to be switched to the power-limited operation mode. At present, the commonly used power-limited operating mode is constant voltage (CV) control, about CV control is mainly based on PI controller, but PI control stability is poor, there are obvious overshoot and oscillation. This paper thus proposes the super-twisting sliding mode (STSMC) CV control algorithm, which is able to control the PV system stably. The PV CV control of STSMC is simulated on Matlab/Simulink software, and the simulation results are basically free of overshoot and oscillation, which verifies the feasibility of the method.