Intelligent Control Strategy for Operation of Park Microgrid Considering High-penetration Photovoltaic Penetration Rate

In the park-level microgrids with photovoltaic system, uncertainties such as DC side voltage fluctuations and system parameter variations, as well as the presence of nonlinear loads, pose a serious threat to the voltage-quality of the photovoltaic inverter, making it difficult to ensure its stable output. To effectively enhance the robustness and the performance of the photovoltaic micro-inverter in dynamic process, an adaptive fuzzy sliding-mode control (AFSMC) framework is proposed in this paper. An adaptive fuzzy controller is designed to approximate the sliding mode control law under the rated model, and the parameter adaptation rate of the fuzzy controller is also designed. This strategy can significantly alleviate the chattering phenomenon and enhance the robustness against the system uncertainties and nonlinear characteristics in the photovoltaic inverter system. Finally, a simulation model was built in MATLAB/Simulink for verifying the effectiveness of the designed control strategy by conducting simulation experiments. The results derived from the simulations demonstrate that the high - quality voltage under both linear and nonlinear loads can be obtained. In addition, when facing load disturbances, it has strong robustness and superior dynamic performance. The proposed AFSMC strategy significantly improve the robustness and transient performance of the photovoltaic power generation system, which provide a new solution for enhancing the quality of the output by photovoltaic inverters.