DC Power supply circuit

摘要

A dc power supply circuit connects a plurality of first dc circuit breakers 3, 4 to a semi-conductor converter 1, returning to the semi-conductor converter 1 through a dc driving part such as an electric railcar 6 connected to each dc circuit breaker 3, 4. A second dc circuit breaker 9 of larger capacity than the first dc circuit breakers 3, 4 is provided in a return circuit 8 and opened when a short circuit current is detected. Current decreasing means 14 opens the second dc circuit breaker 9 to decrease the short circuit current which flows, for example, through a series-circuit of a resistor R and a reactor L.