PARALLEL POWER SUPPLY SYSTEM

摘要

PROBLEM TO BE SOLVED: To obtain a parallel power supply system comprising a plurality of power supply units connected in parallel in which voltage loss is reduced in a reverse current block circuit provided in each power supply unit, and power supply can be sustained stably from other power supply unit upon occurrence of a short circuit failure in a part of power supply units without varying the supply voltage to a load significantly while ensuring the degree of freedom of system design including the length of power supply wiring. SOLUTION: The parallel power supply system is provided with a reverse current block circuit 4 comprising an MOS transistor M4 connected in series with an output path in a power supply unit to form a normally on switch circuit, and a potential difference response circuit which operates to turn off the MOS transistor forcibly when the voltage of the MOS transistor on the current output side exceeds the voltage on the current input side thereof by a specified level or more.