VEHICULAR POWER SUPPLY SYSTEM

摘要

Provided is a vehicular power supply system capable of preventing a reduction in power supply capacity due to a discharge of a main power supply, preventing large currents from being supplied from the main power supply to a capacitor at switch-on, and obtaining generated electricity of a high magnetic flux and a high output. The main power supply (1) is connected to the low pressure side of a DC/DC converter (7) via a first switch (9), and an electric double layer capacitor (6) and a regulator circuit (8) are connected to the high pressure side of the DC/DC converter (7). A permanent magnet is provided to a rotor of an alternator (20) so that a magnetic field in an inverse direction to excitation caused by a field coil (34) is generated in an unguiform magnetic pole unit of the rotor. A power supply control circuit (19) is in an open state during the stop of an engine (3). After the start of the engine (3), the power supply control circuit (19) causes the regulator circuit (8) to operate to cause the alternator (20) to generate electric power, and after the electric double layer capacitor (6) is pre-charged, performs open and close control of the first switch (9) to obtain a connection state.