PURPOSE: To provide a downsized economical protective method for inverter distribution system which can enhance reliability in power supply to a sound section while minimizing effect on the sound section upon occurrence of short circuit fault.
CONSTITUTION: Output from an inverter 11 is interrupted temporarily when ultrahigh speed overcurrent relays 16A, 16B provided in the inverter 11 detect rising of short circuit current while ultrahigh speed overcurrent relays 20a-20c and the like provided for each switch branching the output from the inverter 11 detect the fault section. A switch located immediately in the upstream of the fault section is then turned OFF to isolate the fault section and the inverter 11 is reclosed to resume power supply to a sound section. Electromagnetic switches 18a-18c or solid state contactors are employed as the switches.
AKAZAWA MASAHARU
HORINOUCHI YASUJI
UEYAMA SHUJI
AKASHI NAOYOSHI
NISSIN ELECTRIC CO LTD