A Platform Designed For Valve Regulated Lead-acid Battery And Battery Modeling

Distributed generation, micro grid and electric vehicle have drawn more and moreresearchers’ attention as the energy crisis is getting worse, and estimating the state ofbattery precisely is the chief challenge in these applications. To make contributions, aninvestigation about battery’s equivalent circuits is implemented in this paper, the reasonwhy battery’s state is difficult to predict is also analyzed. Furthermore, an experimentalplatform is designed to study battery’s characteristics and2models are proposed basedon the experimental platform’s data.Firstly, Lots of investigations are implemented, for instance, the classification andcomponents of batteries, the operating principles, characteristics and equivalent circuitsof lead-acid batteries. The reason why battery’s state is difficult to predict lies in thecomplexity of inner electrochemistry of battery, varied operating conditions, and theusage history of battery.Secondly, an experimental platform is designed for a special valve regulatedlead-acid battery (VRLA). This platform includes the software parts and the hardwareparts. The hardware parts incorporate main circuit, control circuit, drive circuit, digitalsignal processing, detection circuit and converter circuit. The software parts incorporatecommunication, protection and data collection.Thirdly, a simulation about the third order model of battery is implemented, and2modeling methods are proposed. Both of the proposed methods are belong to the run-timemodel and can predict the discharge curves precisely if the discharge current is given. Inthe second modeling method, the concept of POD (percentage of discharge) is proposedto compensate the shortage of SOC (state of charge), this method can also be used instudy the consistency among cells, furthermore, the concept of POD is useful in thefuture study.