| 摘要 |
PROBLEM TO BE SOLVED: To obtain a power source unit for a hybrid electric automobile which is excellent in safety and capable of reverse power transmission from an auxiliary power storing means to the main power storing means, while the circuit is miniaturized and made light. SOLUTION: The main power storing means 1 of a hybrid electric automobile charges auxiliary power storing means 21, 21 through DC/DC converters (5, 6, 7). Particularly, in this constitution, lightweight step-up circuits which do not contain a transformer are used as step-up circuits 10, 11, 16 for charging the main charging means 1. When the main charging means 1 is charged, a low potential side of the auxiliary power storing means 22 is turned into a non-grounded state by a low potential ground opening means constituted of switches 12-15. When the main charging means 1 is charged, a user touches by mistake the high potential side of the main power storing means 1 or a high voltage electric system connected with the high potential side, an electrific hazard is not generated because the impedance to earth of the high potential side of the main power storing means 1 is very large. |
