The target regulation voltage setting apparatus for a vehicle on which a
vehicle alternator is mounted includes a first function of calculating a
large first-order delay and a small first-order delay of a rotational
speed of the vehicle alternator at regular time intervals, a second
function of making a judgment on a running state of the vehicle by
determining whether or not the vehicle is in one of an accelerating state
and a decelerating state on the basis of a variation of the large
first-order delay supplied from the first function, and determining
whether or not the vehicle is in a normal state on the basis of a
variation of the small first-order delay supplied from the first
function, and a third function of determining a target regulation voltage
of the vehicle alternator in accordance with a judgment result of the
second function.