ON-VEHICLE POWER SOURCE SYSTEM

To improve accuracy of failure detection for a converter.SOLUTION: An on-vehicle power source system includes: a first converter 14 and a second converter 15 which are connected in parallel between an input portion 12 and an output portion 13, and evenly share an output power during a normal operation; an external signal input portion 16; and a control portion 17 which detects a voltage of the output portion 13, the temperature of the first converter 14, the temperature of the second converter 15, and a signal of the external signal input portion 16, and controls the operations of the first converter 14 and the second converter 15. When receiving the signal from the external signal input portion 16, the control portion 17 causes the first converter 14 and the second converter 15 to start to thereby output a predetermined voltage to the output portion 13 over a first period, and after completion of the first period, the control portion 17 determines failure of the first converter 14 or the second converter 15 based on the temperature difference between the first converter 14 and the second converter 15.SELECTED DRAWING: Figure 1 【課題】コンバータに対する故障検出の精度を向上させる。【解決手段】入力部１２と出力部１３との間に並列に接続されて通常動作時に均等に出力電力を分担する第１コンバータ１４と第２コンバータ１５と、外部信号入力部１６と、出力部１３の電圧と、第１コンバータ１４の温度と第２コンバータ１５との温度と、外部信号入力部１６の信号を検出し、第１コンバータ１４と第２コンバータ１５との動作を制御する、制御部１７と、を含み、制御部１７は、外部信号入力部１６から信号を受信すると、第１コンバータ１４と第２コンバータ１５とを起動させて出力部１３へ所定電圧を第１期間にわたって出力させ、第１期間の完了後に、第１コンバータ１４と第２コンバータ１５との温度差に基づいて第１コンバータ１４もしくは第２コンバータ１５に対する故障判定を行う。【選択図】図１