| 摘要 |
PROBLEM TO BE SOLVED: To evade unnecessary extension of battery chargers, enable recovering the energy which a battery of a trouble car has when a self car rescues the trouble car which cannot run because of a cause except overdischarge of a battery, and using a battery of small capacity, and realize small size and light weight, in a vehicle-mounted bidirectional battery charger using a step-up-down chopper. SOLUTION: A chopper constituted of a switching element Q1 for stepping- down operation, a switching element Q2 for stepping-up operation and a choke coil L led out from the middle point of the elements is used. When the voltage of a battery BAT1 of a self car 1 is higher than the voltage of a battery BAT2 of the other car 2, contactors M1-1, M1-2 are turned on, a switching element Q1 is operated, and step-down charging is performed from the battery BAT1 to the battery BAT2. By operating the switching element Q2, step-up charging is performed from the battery BAT2 to the battery BAT1. |
