Power Fluctuation Stabilization Technology Of Photovoltaic Power Generation System Based On Hybrid Energy Storage

Environmental pollution has been widespread concerned,the new energy will gradually replace coal,oil,natural gas and other traditional fossil fuels.The distributed generation technology has also been widely used.Among them,photovoltaic power generation has been developed rapidly and widely used because of its advantages such as wide resources and easy availability.Independent operation of photovoltaic power generation systems,external conditions such as light intensity,temperature changes will cause the output power of photovoltaic power generation fluctuations,easily lead to system instability.So it need the energy storage system to stabilize.Based on this,this paper presents a photovoltaic power generation system based on hybrid energy storage to stabilize power fluctuations,thereby improving power quality.In this paper,the working principle of photovoltaic cells is analyzed,and the characteristic curves of photovoltaic cells are obtained through simulation experiments.In order to maximize the power utilization,a variable step-size maximum power tracking method is studied.Compared with the traditional maximum power tracking method,the tracking effect is faster and more accurate.Then,the energy storage system is further studied,and several kinds of energy storage methods are compared.A hybrid energy storage structure based on battery and super capacitor is proposed.SimElectronics component library in Simulink is used to build its simulation model.Compared with SimPowerSystems,the model is closer to reality and the simulation result is more accurate.Finally,a kind of inverter which can realize the two-way flow of energy is studied in the control strategy.By using PWM,the power fluctuation is stabilized and the output voltage is stability and smoothness.Based on the above research,the whole simulation model of photovoltaic power generation system is built in this paper.Aiming at the change of light intensity and load,the system is simulated and the voltage waveform is obtained.By analyzing the voltage harmonic content,verify the effectiveness of the proposed suppression technology.