| Photovoltaic power generation and electric vehicle are two important directions in the field of renewable energy. This thesis focuses on photovoltaic module (array) and photovoltaic inverter in the photovoltaic power generation system, and electric vehicle charging station, which includes external characteristics of photovoltaic module (array), control strategies of photovoltaic inverter and reliability of electric vehicle charging station.Firstly, this thesis derives the characteristics equations of photovoltaic cell and photovoltaic module based on their relation and gives the method of establishing simulation model, on the basis of which the characteristics equation of photovoltaic array under complex irradiation is derived. According to the characteristics equation, maximum power point tracking algorithm using steepest ascent method is deeply studied. And a new maximum power point tracking algorithm using approximate gradient method is proposed to automatically judge the searching direction and adjust the step size as steepest ascent method does, and to adopt simple hardware as perturbation and observation method does. The proposed algorithm can improve practicability and validity of traditional algorithms.Secondly, to overcome the defect of the existing fuzzy control algorithms of photovoltaic grid-connected inverter, such as relying on experience of experts excessively, adjusting membership and fuzzy rules repeatedly, a grid current regulating algorithm using T-S fuzzy model is proposed on the basis of establishing mathematical model of inverter. Simulation result demonstrates that the algorithm can adjust the duty cycle accurately and make grid current track the reference current rapidly and accurately.Thirdly, for the purpose of overcoming the defect of being unable to deal with unknown or inaccurate parameters for T-S fuzzy control, predictive current control algorithm of photovoltaic grid-connected inverter is deeply studied and an improved predictive current control algorithm is further proposed. The proposed algorithm is optimized through adjusting the control objective, which can reduce the influence had on stability by parameter deviation as a result of unknown inductance, improve the reliability and accuracy of algorithm and increase the dismatch of model inductance and actual inductance on the premise of stability. Fourthly, aiming at overcoming the defect of neglecting resistance and disturbance signals of predictive current control algorithm, a self-adaptive control algorithm suitable for photovoltaic grid-connected inverter is proposed. The proposed algorithm is designed based on Lyapunov's direct method, which can realize adaptive adjustment of the unknown parameters according to realtime data, on the premise of reaching control objective and stability. Then the influence had on the proposed algorithm by disturbance signals is further studied, which can realize realtime prediction of disturbance signals and improve greatly the interference rejection capability.Finally, typical topologies of electric vehicle charging station are studied with reliability analysis methods. A kind of reliability calculation method suitable for multi-stress system is proposed, based on which both reliability and mean time to failure of typical topologies are calculated. Through comparison of typical topologies, taking account of reliability and economics, two kinds of charging station, namely cold-standby redundancy power supplying mode charging station and distributed charging station are proposed. Then through introducing cold-standby redundancy power supplying mode to distributed charging station, a kind of distributed charging station with N+1 redundancy is proposed. Through comparison of reliability for the three proposed kinds of topologies, distributed charging station with N+1 redundancy is verified to be the optimum structure integrating both reliability and economics.
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