Patent attributes
The vehicle-use power supply apparatus includes an alternator driven by an engine mounted on a vehicle to generate electric power in accordance with a command value, a battery electrically connected to the alternator to be charged by the alternator, and connected to electrical loads mounted on the vehicle to apply a power supply voltage to the electrical loads. The vehicle-use power supply apparatus further includes a first function of determining, as a power generation cost, an increase amount of fuel which the engine consumes for the alternator to generate electric power, and a second function of transmitting the command value to the alternator, the second function being configured to determine the command value on the basis of the power generation cost determined by the first function such that a change rate of the power supply voltage does not exceed a predetermined limit value.