Sliding-Mode-Based Control Strategy for a Solar Multi-Port Three-Level DC-DC Converter Under Harsh System Uncertainty

In this paper, a robust control approach using a sliding-mode-based (SLMB) control strategy has been designed for a solar multi-port three-level dc-dc converter that is specifically tailored for harsh environmental conditions, such as solar panel failure and load fluctuations. The multi-port three-level dc-dc converter has one solar input, one buck battery port, and a boost output. The sliding-mode control is designed to regulate the main boost output voltage at the desired magnitude in a three-level control structure, while the maximum power tracking is simultaneously executed for the solar input. To maintain robustness against harsh system uncertainties, a sliding mode control law in which the load and input power parameters are eliminated is constructed. Therefore, the proposed control strategy is theoretically insensitive to input current and load fluctuations. The proposed control strategy’s efficacy is validated in simulations, and its performance is compared to that of a well-tuned conventional PI controller.