Patent ID: 8330468

Claim:
A vehicle control system installed in a motor vehicle having a rechargeable battery, said vehicle control system incorporating an automatic engine control apparatus having an automatic engine stop function and said vehicle control system comprising judgement circuitry configured to judge a charge condition of said battery and to selectively enable and inhibit said automatic engine stop function based upon said charge condition; wherein said judgement circuitry is configured to: at a first time point while said engine is running, calculate a predicted charging current integral by calculating successive values of a predicted charging current of said battery within a prediction interval extending from said first time point to a final time point at which said predicted charging current attains a predetermined final value, and integrating said predicted charging current with respect to time over said prediction interval, to obtain a predicted charging current integral, said predicted charging current values being calculated assuming a condition of constant-voltage charging of said battery at a predetermined voltage throughout said prediction interval, and said charging current final value and said predetermined voltage, in combination, being indicative of a predetermined value of charge stored in said battery, subtract said predicted charging current integral from a difference between a predetermined upper limit value and a predetermined lower limit value of charge stored in said battery, to obtain an initial allowable discharge amount, and subsequent to said first time point, calculate an actual current integral by integrating successive measured values of charge and discharge current of said battery with respect to time, from said first time point up to a current time point; said judgement circuitry being configured to selectively enable and inhibit said automatic engine stop function, subsequent to said engine starting, based upon said actual current integral in conjunction with said initial allowable discharge amount.