Research On Maximum Power Point Tracking For Photovoltaic Power System

Nowadays,with the increasing burden on energy exhaustion and environment pollution,as a cleanly and renewable energy,Solar Energy has became a hotspot of the whole world.In photovoltaic power generation systems,the photovoltaic cell has characteristics such as non-linear,time-varying and can not establish a precise mathematical model,this paper real-time adjustments to power point of photovoltaic cells to make photovoltaic system in the maximum power point,improve the stability of the system.As the photovoltaic cell has characteristics such as non-linear,time-varying and can not establish a precise mathematical model,The traditional PID controller can not satisfy the requests of high-performance control,such as accurate speed or torque control and robustness,this paper apply the fuzzy control tO maximum power point tracking control of photovoltaic power generation system from its Volt-Ampere Characteristics,and apply Cuk converter to achieve MPPT.Fuzzy Control can respond quickly to changes in the external environment,always working to make photovoltaic system in the maximum power point,improve the efficiency of the photovoltaic system.Based on the theory,then a full digital photovoltaic power system based on TI's DSP is designed.In it TI's DSP is used as the central process unit,and IPM is used in the power supply unit.The digitally realized methods of fuzzy PID controller are introduced detailedly.Based on Matlab/Simulink the performance parameters of the controller are analyzed.Finally,the performance of traditional PID and fuzzy PID controller is compared.The simulation and experiment results show the fuzzy PID can quickly respond to changes in the external environment,which can effectively eliminate the work of the maximum power point of the oscillation and improve the stability of the system.