METHOD OF ESTIMATING BATTERY CHARGE STATE IN BATTERY MANAGEMENT SYSTEM FOR ELECTRICAL VEHICLE

摘要

PURPOSE: A method is provided to be capable of compensating a current state-of-charge(SOC) estimation value at a real time by estimating an exact SOC of a battery from a relationship of a battery voltage and the SOC. CONSTITUTION: A discharge current, a voltage and a temperature are measured through a current sensor, a voltage sensor and a temperature sensor(S201). Adjusted is a parameter needed for SOC estimation by a voltage characteristic with respect to a battery discharge current(S202). A SOC is estimated using a Peukert equation with respect to a battery discharge current measured through the current sensor(S203). If the SOC estimation is completed, whether the measured discharge current is included in an appointed current region is judged(S204). If so, an IV check value is increased by '1'(S205), and whether the increased IV check value is over an appointed value is judged(S206). If so, the SOC estimation value is compensated using an SOC compensation estimation curve with respect to a constant discharge current(S207). If compensating of the SOC estimation value is completed, the IV check value is reset(S208) and the compensated SOC is displayed(S210).