Research On Large-Scale Energy Storage Battery Management System

Battery energy storage system has been widely used in smart grid from power generation to all aspects of electricity, its role is mainly divided into load shifting, backup power, the ability to raise new energy grid and grid frequency regulation,the key equipment of Battery energy storage include batteries, battery management systems BMS, PCS, and monitoring control system, etc. Therefore, as an important part of the battery energy storage system,study of battery management system has important significance for longer battery life, lower operating costs.There are a lot of battery management system development vendor. However, battery management systems from different vendors lack of unified interfacesthere.Because of the difference communication interfaces and communication protocols,battery management system can be replaced and maintainability very poorly,as well as hindered the development of the battery management system.The battery management system has been designed,and CANopen protocol has been applied to battery management system,achieve standardization and unification communication interface of battery management system.Any device,which supported CANopen protocol,can connected to the battery management system CAN bus,and access data of battery management system.Solved problems include battery management system interface is not uniform, replacement of the battery management system apparatus may poor,difficult to control or direct docking with other management device,and the slow development of battery management system of domestic. Studied lithium iron phosphate,relationship between open voltage and SoC,battery internal resistance and SoC has been measured.Kalman filter algorithm has been used in SoC estimate,and implemented in BMS. The main chip of Battery management system is STM32F103C8T6, as well as LTC6803-3in voltage detection.Industrial control computer based PC/104bus has been applyed in Battery management cluster system(BCMS).CANopen protocol creative applied in communication between battery managemnet unit(BMU) and BCMS.Any device supports CANopen protocol may be connected to CAN bus,share the BMS parameters.This paper introduced Kalman filter estimate battery SoC. data sampling, monitoring, display, alarm and other functions.CANopen protocol has been studied and achieved in BMS,make it convenient to connected BMU to BCMS,solve the problem of communication interface is not uniform,and the consequent. The BMS used in "50kW storage access system",and achieved satisfactory result in CANopen communications consistency, battery voltage and temperature measuring, SoC estimation.