Residual battery capacity estimation management system and method

Abstract

The invention discloses a residual battery capacity estimation management system and method. Application condition of open-circuit voltage capacity estimation is fully taken into consideration, and under the condition of meeting the use condition, fine multi-temperature-range OCV data accuracy is utilized to make up for the error due to long-time ampere-hour integration, and thus estimation precision is improved; meanwhile, under the condition of not meeting the OCV condition, platform period and mutation period judgment is introduced; in the platform period, estimation is carried out through an ampere-hour integration method; and in the mutation period, estimation is carried out through an interpolation method, and corresponding early warning processing is carried out, thereby preventing overcharging / overdischarging of a battery effectively, prolonging the recycle service life, and reducing accident risk. The two cases above are measured through test, and influence of different temperatures and aging factors is obtained; and corresponding correction processing is carried out on estimated value, and thus estimation precision is further improved.

Description

technical field [0001] The invention relates to a battery state of charge judgment and remaining capacity estimation system and method, in particular to a battery remaining capacity estimation management system and method. Background technique [0002] The increasingly severe environmental pollution and energy crisis have accelerated the popularization and development of electric vehicles. [0003] During the use of electric vehicles, it is necessary to monitor the state of charge (StateOfCharge, referred to as SOC) of the battery pack in real time and accurately estimate the remaining capacity of the battery. An important factor in the safety of people and vehicles. [0004] It can be seen from the charge and discharge characteristic curve of the battery that there is a period of rapid rise and fall of the battery voltage in the initial stage and the end stage of charge and discharge respectively, except for other stages, the voltage changes little and is relatively stable...

AI Technical Summary

Problems solved by technology

They each have their own scope of application and advantages and disadvantages: the open circuit voltage method is simple and convenient, but it can only be used when the battery pack is not loaded, and cannot be applied to the charging and discharging process; the ampere-hour integration method is widely used, but each time the current collection process Both will introduce measurement errors, and will become larger and larger as time goes by, resulting in larger and larger estimation deviations; the Kalman filter method has high accuracy, but due to the need to establish a real state model for specific battery products in advance and measurement equations, so the implementation is difficult and the algorithm is complex

[0007] The state of charge of the battery is not only related to the charge and discharge current, but also closely related to the charge and discharge characteristics of the battery, internal resistance, the ambient temperature, and the cycle life of the battery, that is, the degree of aging. If it is not considered in the SOC estimation process The influence of these factors will inevitably lead to large errors

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