A rotary electric machine has two sub-windings shifted by 30 degrees from each other. Each sub-winding is connected to an individual bridge which has MOS transistors on the ground sides. It is possible to supply a charging current even at a low rotational speed by switching the MOS transistors at a high-frequency. The basic components of magnetic force are canceled because of the shifted sub-windings. The switching components of the magnetic forces generated by the switching operation are canceled by switching two groups of the MOS transistors in opposite states. As a result, it is possible to decrease the magnetic noise significantly.
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.
An inverter device is mounted on the rotating electric machine body The inverter device includes a module unit having a converter circuit and a control unit that controls the operation of the converter circuit. The converter circuit is configured by connecting a plurality of the following series circuits in parallel, each of the series circuits includes a P-channel MOS semiconductor device disposed at a higher potential side and an N-channel MOS semiconductor device disposed at a lower potential side which are electrically connected in series. An electric power that is supplied from a battery or an electric power that is supplied to the battery is controlled.
A vehicle-mounted electrical generating system has a first voltage system which operates from a high supply voltage and a second voltage system which operates from a low supply voltage that is substantially constant, and an electrical generator for supplying power to operate the first voltage system at a voltage determined by the level of field current of the generator, with the field current being derived from the low supply voltage of the second voltage system. The specifications of the field winding of the electrical generator can thereby be optimally established irrespective of the value of the high supply voltage.