Patent ID: 8548761
Filing Date: 2013-10-01
Classification: B60L,G01R,Y02T

Abstract:
1. A method for measuring SOC (State Of Charge) of a battery in a battery management system, comprising: obtaining, by a battery information obtaining part, current data, voltage data and temperature data by measuring current, voltage and temperature of the battery; calculating, by a current accumulating part, SOCi (State Of Charge based on current) by accumulating the current data; calculating, by a OCV (Open Circuit Voltage) calculating part, OCV using an equivalent circuit model in which the current data, the voltage data and the battery are simply expressed by an electric circuit; estimating, by a SOCv (State Of Charge based on voltage) estimating part, SOCv using the temperature data and the OCV; and judging, by a SOC setting part, a current state of the battery for a desired period of time, and setting up, by the SOC setting part, the SOC of the battery using at least one of the SOCv and the SOCi, wherein the judging of the current state of the battery for the desired period of time, and the setting of the SOC of the battery using at least one of the SOCv and the SOCi, by the SOC setting part, comprises: judging the current state of the battery for the desired period of time, and measuring target SOC of the battery using at least one of the SOCv and the SOCi; calculating ΔSOC which is a difference between the target SOC at a present time and the SOC at a previous time; comparing the ΔSOC with a first critical value; renewing the target SOC at the present time according to a predetermined algorithm and then setting up the renewed target SOC to the SOC of the battery at the present time, if the ΔSOC is larger than the first critical value; and setting up the target SOC at the present time to the SOC of the battery at the present time, if the ΔSOC is not larger than the first critical value, and wherein the algorithm is −SOC(n+1): SOC of the battery at the present time; −SOC(n): SOC of the battery at the previous time; −ΔSOCi=I(n+1)*Ts/Capa*100%; −(I(n+1) is a current value at the present time, and Ts is a current sampling period, and Capa is a rated capacity of the battery); −0(%/100 msec)<gain<0.1(%/100 msec); and −ΔSOC is a value produced by subtracting the SOC measured at a previous time (n) from the SOC measured at a present time (n+1).