A detecting means easily detects the abnormality of a generator having a
plurality of power supply units. Each of the power supply units includes
one of a plurality of output windings L1 to L4, which are wound
independently of each other around single iron core, and one of
rectifiers 2 to 5 that are provided in correspondence to the output
windings and produces an integrated output. Controllers 33 to 35 control
the rectifiers such that the output voltage corresponds with a target. A
voltage deviation judgment section 37 outputs the abnormal signal when
one of the output voltages of the rectifiers 2 to 5 is different from
remains. A current deviation judgment section 39 outputs the abnormal
signal when one of the output currents of the rectifiers 2 to 5 is
different from remains. When the abnormal signal is detected, the outputs
of the rectifiers 2 to 5 are stopped.