Abstract:

At present the lead-acid battery is widely used as the backup power of station DC system,but it has some inherent defects.The research of station DC backup power to replace the lead-acid battery with lithium iron phosphate battery is of great significance to comprehensively improve the reliability and safety of DC power system.Based on the 220 V DC backup system for the 220 kV substation,the design of lithium iron phosphate battery DC power system is put forward,including the basic function,the parameter design and the small capacity multi-channel parallel electrical topology.The group mode of lithium battery and the parameter design of battery management system (BMS) are further analyzed.Finally,based on the special charge and discharge characteristics of lithium iron phosphate battery,the charge and discharge strategy,capacity verification and maintenance strategy and the BMS system alarm protection strategy suitable for the lithium iron phosphate battery are studied,which can provide design basis and research basis for the implementation of the lithium electrification substitution transformation of the station lead-acid battery.

Key words: lithium iron phosphate battery, electrical topology, battery management system, charge discharge strategy, protection strategy