Patent ID: 8918300
Filing Date: 2014-12-23
Classification: G01R

Abstract:
1. An apparatus for battery state of charge estimation comprising: a charge/discharge current detection unit configured to detect a charge/discharge current value of a battery; a terminal voltage detection unit configured to detect a terminal voltage value of the battery; a current integration method state of charge estimation unit configured to estimate a current integration method state of charge by integrating the charge/discharge current value detected by the charge/discharge current detection unit; an open circuit voltage estimation method state of charge estimation unit configured to estimate an open circuit voltage value of the battery from the charge/discharge current value detected by the charge/discharge current detection unit and the terminal voltage value detected by the terminal voltage detection unit and to estimate an open circuit voltage estimation method state of charge from the open circuit voltage value; a first difference calculation unit configured to calculate a state of charge difference between the current integration method state of charge obtained by the current integration method state of charge estimation unit and the open circuit voltage estimation method state of charge obtained by the open circuit voltage estimation method state of charge estimation unit; an error estimation unit configured to estimate, based on the state of charge difference obtained by the first difference calculation unit, an error as a state quantity of an error model by using the error model; and a second difference calculation unit configured to calculate a state of charge of the battery by subtracting the error estimated by the error estimation unit from a state of charge, between the current integration method state of charge estimated by the current integration method state of charge estimation unit and the open circuit voltage estimation method state of charge estimated by the open circuit voltage estimation method state of charge estimation unit, that is subtracted in the first difference calculation unit, wherein the error estimation unit includes a Kalman filter that uses the error model.