The MPPT Control Of Photovoltaic System Based On Type-2 Fuzzy Model

Since the solar energy has been actively promoting in the world,photovoltaic power generation has attracted more and more attention.However,the researches show that photovoltaic power generation is not perfect.There are still many problems,such as high cost of electricity,low efficiency of photoelectric conversion.In addition,the problems will affect the output of photovoltaic cells,and affecting the maximum power of photovoltaic power generation,when the external environment changes,such as the change of temperature and the difference of the illumination intensity.In order to improve the efficiency of solar photovoltaic power generation system,people often catch and track the maximum power point of photovoltaic power generation to improve the output power of photovoltaic cells.In this way,the photovoltaic system can achieve maximum power output regardless of the changes of the temperature and illumination.In recent years,the control method of the maximum power point tracking(MPPT)of photovoltaic system have been developed by many famous scholars in the world.In this study,the MPPT control method of photovoltaic system based on the type-2 fuzzy model is applied to achieve the maximum power point tracking of solar photovoltaic power generation system.The main work of this paper includes the following several aspects:For solar photovoltaic system,the MPPT problem is studied based on Lyapunov stability theory,type-2 fuzzy logic,and linear matrix inequality(LMI)technology.The type-2 T-S fuzzy model is first established.Next slack variables are introduced which can reduce conservation of stability conditions based on LMI.The existence conditions of state feedback controller are obtained.The global asymptotic stability of the closed-loop system in the sense of Lyapunov can be ensured.The control law of state feedback controller about MPPT is given.Finally,the numerical simulations are given to illustrate the effectiveness of the proposed method.The MPPT control method is investigated base on type-2 T-S fuzzy model with actuator saturation.The dynamic model of the photovoltaic power generation system is established,and the controller is designed.The fuzzy Lyapunov function and slack matrix variables are introduced to reduce the conservatism of the system.Based on the Lyapunov stability theory,the close-loop system stability is proved and the control gain can be solved by using LMI technique.The effectiveness of the proposed method is verified by simulating the photovoltaic system.For the solar PV system,the MPPT is studied by considering the saturation input of the actuator,based on Lyapunov stability theory,type-2 fuzzy logic,and the event-triggered method,and the existence conditions of state feedback controller are obtained.The global asymptotic stability of the closed-loop system in the sense of Lyapunov can be ensured,and the control method of state feedback controller about MPPT is given.The gain of thecontroller can be obtained by LMI technique.Finally,the simulation results verify the effectiveness of the proposed method.In the end,several parts of the study are summarized.The effectiveness of the method employed is indicated.The the prospect of the future work plan is made.