Method, device and system for estimating peak power of battery pack

Abstract

The invention discloses a method, a device and a system for estimating the peak power of a battery pack. The method comprises the following steps of obtaining a discharge power limit value and a charging power limit value of the battery pack according to the charged state of the batteries in the battery pack and the temperature of the battery pack; acquiring the minimum voltage value and the maximum voltage value of the batteries in the battery pack, and determining the discharge peak power limit coefficient and the charging peak power limit coefficient based on the preset voltage limit condition, the minimum voltage value and the maximum voltage value; and calculating the discharge peak power of the battery pack and the charging peak power of the battery pack based on the discharge power limit value, the charging power limit value, the discharge peak power limit coefficient and the charging peak power limit coefficient. According to the method of estimating the peak power of the battery pack provided by the embodiment of the present invention, it is possible to adjust the peak power of the batteries in the battery pack by the battery voltage so as to avoid the risk of undervoltage or overvoltage during discharge or charging of the peak power.

Description

technical field [0001] The invention relates to the field of battery technology, in particular to a method, device and system for estimating the peak power of a battery pack. Background technique [0002] Cell peak power prediction is an important function of electric vehicle battery management system. The peak power prediction of the battery cell can evaluate the charging and discharging power limit capability of the power battery pack under different State of Charge (SoC), and optimally match the relationship between the battery pack and the vehicle power performance to meet the needs of electric vehicles. Excellent acceleration and climbing performance, and maximize the regenerative braking energy recovery function of the motor. Moreover, the peak power estimation of the battery cell has important theoretical significance and practical value for rational use of the battery, avoiding overcharging or overdischarging, and prolonging the service life of the battery pack. ...

AI Technical Summary

Problems solved by technology

However, in the process of the battery pack from rest to discharge, the initial polarization voltage of the battery pack is 0 when the battery pack is at rest. With the increase of discharge current and the increase of discharge time, the polarization voltage of the cells in the battery pack gradually increases. Large, the estimated peak power of the cell will be much greater than the actual capacity of the cell, and there will be a risk of undervoltage or overvoltage if the peak power is used to discharge or charge

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