Patent ID: 7506182
Filing Date: 2009-03-17
Classification: B60L,H02J

Abstract:
1. A power supply system mounted on a vehicle, comprising: a first storage battery; an automotive generator for generating a voltage and charging said first storage battery with the generated voltage; a second storage battery connected to an electrical load; power conversion circuitry having a power converter including a semiconducting switching device connected between said first storage battery and said second storage battery, said power conversion circuitry being operable in a first mode in which a voltage at said second storage battery is maintained at a substantially constant level and in a second mode in which the voltage at said second storage battery varies with a voltage at said first storage battery; control circuitry for controlling a power transistor according to the voltage at said second storage battery when said power conversion circuitry is operating in said first mode and continuously setting said semiconducting switching device in a conducting state when said power conversion circuitry is operating in said second mode; and a controller for operating said power conversion circuitry in said first mode when power consumption of said electrical load is lower than a specified value and controlling said generator so that the generated voltage undergoes a transition at a first rate, and operating said power conversion circuitry in said second mode when power consumption of said electrical load is higher than said specified value and controlling said generator so that said generated voltage undergoes a transition at a second rate lower than said first rate.