Lithium iron phosphate power battery management system and management method

Abstract

The invention discloses a lithium iron phosphate power battery management system and a lithium iron phosphate power battery management method. The lithium iron phosphate power battery management system comprises a main controller, a voltage detection circuit, a temperature detection circuit, an insulation monitoring circuit, an equalization circuit, a protection circuit, a DC / DC (direct current) power supply circuit, a pre-charging circuit, a cooling fan, a power battery pack, a personal computer (PC), a vehicle-mounted controller and a storage module. The lithium iron phosphate power battery management system has the following functions of detecting monomer voltage and total voltage of a battery, detecting charging and discharging currents of the battery pack, diagnosing faults of the battery pack and performing mandatory protection for over charging, over discharging and equalization and temperature protection, accurately estimating various states (SOC, SOH and RUL) of the battery pack, performing efficient and rapid equalization, charging in advance, measuring insulation of the battery pack, recording running and fault data of the battery pack, communicating with the vehicle-mounted controller and a display system, and communicating with a battery charger and providing battery charging information for the battery charger.

Description

Technical field [0001] The invention relates to a lithium iron phosphate power battery management system and management method. Background technique [0002] Energy crisis and environmental pollution are two major problems facing the world today. Electric vehicles are widely welcomed by people for their energy-saving and environmental protection, and they have become an inevitable trend of future automobile development. my country's "Twelfth Five-Year Plan" has established the strategic layout of "three verticals and three horizontals" for electric vehicles. The three verticals are hybrid vehicles, pure electric vehicles, and fuel cell vehicles; the three horizontals are batteries, motors, and electronic controls. Among them, as a key component of electric vehicles, the performance of vehicle-mounted power batteries is crucial to the power, economy and safety of the entire vehicle, and is a key factor restricting the scale development of electric vehicles. Because of its high ...

AI Technical Summary

Problems solved by technology

[0003] However, the abuse ability of lithium-ion power batteries is poor, and the charging and discharging characteristics are greatly affected by the environment. When lithium-ion batteries are connected in series and applied to electric vehicles, their performance is far inferior to that of single batteries, and even safety problems arise.

The reason is that lithium batteries are inherently highly nonlinear, strong coupling, hysteresis effect and time-varying characteristics, resulting in low modeling accuracy and poor versatility. SOC (State of Charge), SOH (State of Health), RUL (Remaining Useful Life) The estimation error is large, and the equalization effect is not good. With the aging of the battery, the estimation error of the battery SOC and other states is getting larger and larger, and the inconsistency between the cells is becoming more and more obvious, resulting in excessive lithium-ion battery life. Overcharging and overdischarging will reduce the available capacity, reduce the cycle life, unreasonable energy management, and break down halfway, etc., which will eventually lead to safety accidents over time

Therefore, for lithium-ion power batteries, the battery management strategy is more complicated

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