Research And Implementation Of Energy Storage Battery Simulator

Due to the randomness and intermittent of renewable energy in the process of power supply, energy storage technology can make the random and intermittent renewable resources adjustable and controllable,which can improve the quality of power grid,ensure the security and stability, reduce the power loss,realize peak clipping and valley filling and improve the performance of micro grid.But energy storage battery have the characteristic of high cost and inflexible parameter adjustment,so the research of energy storage battery simulator is of great significance.A simulator which can simulate the external characteristics of the battery will help to promote the research of energy storage technology.Firstly, the paper introduces the background and significance of the selected topic,and then introduces the research status of micro grid technology and energy storage technology briefly.Then,the model of lead-acid battery, liquid flow battery and lithium ion battery are analyzed,and the output voltage,output current and SOC relational formula is established according to the equivalent circuit model respectively.Then according to the output external characteristic needs of the simulated battery,a topology scheme of three kinds of battery simulator is proposed.Compare the advantages and disadvantages of three kinds of battery simulator topology and the platform of experimental requirements,A topology scheme based on T type three-level voltage source PWM rectifier(VSR) is determined.The proposed simulator can be used to simulate the external characteristics of different kinds of cells and different parameters.The simulator uses back-to-back mode.The rectifier is used as a battery simulator,and the inverter is used to simulate loads.Then the core part of the battery simulator is presented-VSR,the design of VSR filter and the method of parameter selection of LCL filter are introduced in this paper.Based on the grid voltage oriented vector control,this paper presents the grid control strategy of VSR.Finally, the simulation algorithm of the battery simulator is introduced.Finally, based on the Matlab/Simulink simulation platform and the 20kW converter experimental platform,this paper analyses and proves the situation of charging and discharging, no-load and full load switching,full charge and full discharge switching of battery simulator,and confirm the feasibility of the battery simulator.