| 摘要 |
PURPOSE:To reduce the overall size by arranging diodes for performing three rolls of matching, counter-flow blocking and transistor protection at respective input sides and sharing the inputs at the cathode side thereby performing interruption through a single large-capacity transistor. CONSTITUTION:Currents are fed normally from both terminals (a), (b) to respective diodes 2 and combined at the cathode side of the diodes 2. The resultant current is fed through a transistor 1 and a current sensor 5. Upon occurrence of a short circuit in a system connected with a DC circuit breaker, the current sensor 5 detects overcurrent while a voltage sensor 6 detects undervoltage, then a control section 4 interrupts the base current of the transistor 1 through a base drive circuit 3 so that the transistor 1 is turned OFF to interrupt fault current. |
