NOVELTY - The system (10) has first switch (15) provided in electrical wirings (14Aa,14Ab) between second generator (11B) and second charger (13B). Second switch (16) is provided in electrical wirings (14Ba-14Bd) between second charger and first charger (13A). An electric control apparatus (17) is provided to control charge to first and second chargers, with respect to manual regeneration of diesel particulate filter of exhaust-gas processing apparatus in internal combustion engine (2), while first switch is made into disconnected state and second switch is made into energized state.    USE - Power source system for vehicle (claimed) such as motor vehicle such as truck.    ADVANTAGE - The over-discharge of the battery can be prevented by controlling the charging capacity of the charger, and electric power generation in manual regeneration of diesel particulate filter, so that the operation of the internal combustion engine in the state with inadequate charge condition of the charger can be avoided, thus the deterioration of fuel consumption can be suppressed. The power consumption of electrical component at the time of start-up of the internal combustion engine can be reduced with electricity from second charger at the time of the operation of the idle stop start apparatus.    DETAILED DESCRIPTION - The first generator (11A) is driven with drive shaft (2a) of internal combustion engine. The first charger is provided for charging electricity generated by first generator to electrical component (20) through electrical wiring (21) of first electricity supply system (10A). The second generator is driven directly or indirectly with transmission shaft (4) between internal combustion engine and driving wheel (3). The second charger is provided to charge electricity generated by second generator to first charger through electrical wiring of second electricity supply system (10B). An INDEPENDENT CLAIM is included for an electric supply method of vehicle.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of the power source system of motor vehicle.    Internal combustion engine (2)    Drive shaft (2a)    Driving wheel (3)    Transmission shaft (4)    Power source system (10)    First electricity supply system (10A)    Second electricity supply system (10B)    First generator (11A)    Second generator (11B)    First charger (13A)    Second charger (13B)    Electrical wirings (14Aa,14Ab,14Ba-14Bd,21)    First switch (15)    Second switch (16)    Electric control apparatus (17)    Electrical component (20)