The Maximum Power Tracking Control For Photovoltaic Array Generators Based On Fuzzy Approach

With the increasing of the fossil energy and environmental contradiction, people begin to search for renewable energies to replace the fossil fuels. Solar power, wind power, and nuclear power have been greatly discussed in the past few years. Solar power is a renewable source, absolutely pollution free, generates no noise, and inexhaustible. Photovoltaic power generation has become one of the main ways of using solar energy, but the power generation efficiency is low. In this paper, for the solar photovoltaic module, the fuzzy control problem of maximum power point tracking(MPPT) is investigated via the traditional method of fuzzy rules, the maximum power voltage(MPV) strategy and direct maximum power(DMP)strategy. The main work of this paper includes:According to the characteristics of photovoltaic cells and the experience knowledge of maximum power tracking control, the fuzzy rules and fuzzy membership function are determined. Then, a fuzzy controller is designed by using a traditional fuzzy control method.The simulation results of the fuzzy system demonstrate that the control technique have a good performance.According to the physical mechanism of photovoltaic module and considering the two cases of components having no uncertainty and components having uncertainty, respectively,the Takagi-Sugeno fuzzy models are constructed. Based on the theory of Lyapunov stability and the strategy of the maximum power voltage(MPV), the sufficient conditions of guaranteeing the asymptotic stability of the photovoltaic system are given. In addition, the controller gains can be designed from linear matrix inequality(LMI) techniques under the aforementioned two cases. The simulation results demonstrate that the proposed method can realized the MPPT.According to the physical mechanism of photovoltaic module and considering the two cases of components having no uncertainty and components having uncertainty, respectively,the Takagi-Sugeno fuzzy models are constructed. Based on the theory of Lyapunov stability and the strategy of the direct maximum power(DMP), the sufficient conditions of guaranteeing the asymptotic stability of the photovoltaic system are given. In addition, the controller gains can be designed from linear matrix inequality(LMI) techniques under the aforementioned two cases. The simulation results demonstrate that the proposed method can realized the MPPT. Compared with the control strategy based on the maximum power voltage(MPV), the fuzzy controller based on the maximum power directly(DMP) is better and tracking faster.