Research On Application Of Power Forecasting And Hybrid Energy Storage In Wave Energy Generation System

Entering the 21 st century,society's demand for energy is increasing year by year.The depletion of fossil fuels,such as coal and petroleum and the intensification of environmental pollution force people to accelerate the development of new energy.The ocean is rich in various forms of energy that can provide enough sufficient renewable energy for human.However,the output power of wave power generation has greater fluctuation and randomness,it will affect the safe operation of the power grid,which greatly restricts the development of wave power integration.There are two methods to improve the stability of wave power generation.One is to improve the prediction accuracy of wave power output power and provide reference for the power grid dispatching department;the other is the application of energy storage system to smooth the wave power.This paper studies the wave power prediction and the wave power smoothing control strategy based on hybrid energy storage system.The mathematical model of the wave generation system was studied.The permanent magnet linear generator was used to build a complete wave power system model.This paper predicts the output power of wave power,BP neural network and GA-BP neural network are applied to improve the prediction accuracy in turn.The BP neural network prediction model is built,using genetic algorithm has the advantage of global searching,to optimize the weights and thresholds of BP neural network and avoid the premature convergence of neural network to the local minimum value,this will improve the predictive ability of BP neural network.By predicting the power of the two algorithms,the prediction results show that the prediction model of the BP neural network prediction model optimized by genetic algorithm has better prediction accuracy and achieve the expected effect.Finally,Combining the high energy density of battery and the high power density of supercapacitor,the hybrid energy storage system with complementary characteristics was proposed to suppress the fluctuation of wave power.The energy storage system composed of battery and supercapacitor to solve the problem of power fluctuation,the topology of the hybrid energy storage system is analyzed and determined,the supercapacitor and the battery connected in parallel by the bidirectional DC/DC converter.The initial charging and discharging values of battery and supercapacitor aredetermined by low-pass filter method,the fuzzy controller is established to adjust the actual charging and discharging power of the energy storage elements and adjust imbalance power between energy storage elements.At last,the simulation results show the effectiveness of the control Strategy in suppressing power fluctuations of wave power.