Modeling Of Vanadium Redox Flow Battery And Design Of Control System

Vanadium redox flow battery(VRB) is storage device by using the circulation of electrolyte circulation, in the process of charge and discharge, only the electrolyte ion valence change, and avoid cross-contamination caused by different kinds of active substance infiltration, has the advantages of high efficiency, long service life, large capacity, the depth for charging and discharging and so on, has a great application value in the electric energy storage.More and more countries pay attention to the energy storage technology research, its development prospect is broad.This paper study the vanadium battery charge-discharge principle and working process, build VRB model according to the Nernst equation, includes electrochemical model and mechanical model, deals with the influence factors of charge-discharge, the influence factors mainly are current, temperature, flow rate and so on, introduce the methods of the charge and discharge, select constant current charge and discharge mode for vanadium redox battery, confirm that the vanadium battery has good charging and discharging characteristics through the simulation at the same time, discuss the influence of current and flow rate on the vanadium battery charge-discharge performance, at different SOC, find out the optimal flow value of electrolyte by simulation, can use piecewise adjustment flow rate method for the charge and discharge, optimize VRB operation, make the battery work in good condition.This paper takes5kW VRB as an example from Prudent Energy company in Beijing, design the control system for vanadium battery,design software and hardware, the main hardware equipment selection according to the requirements of the system for vanadium redox battery energy storage system,mainly the selection of IPC, data acquisition module, sensors and state of charge detection device. State of charge detection is mainly through an circuit independent from Vanadium redox flow battery, using a voltmeter to measure the voltage, and last get SOC according to function relations between the open-circuit voltage and charge state.At the same time, use Force Control configuration software to construct the vanadium battery monitoring system to monitor the state parameters of vanadium battery:voltage, current, temperature, liquid level, flow rate, the collected data record is stored into the database, simulate operating system, dynamic display of the working process of vanadium battery, ensure vanadium redox flow battery safe, stable and high efficient operation.