Current-Limiting Solid State Circuit Breaker Arrangement

A method for limiting a current in case of a short circuit using an apparatus 1, the method comprising:

• providing a main switch, arranged in series between an apparatus-input and an apparatus-output;
• providing a first parallel-diode in backward direction and a second parallel-diode in forward direction, the first parallel-diode and the second parallel-diode arranged in series and in parallel to the main switch, with a first central node between them;
• providing a first branch diode in forward direction and a second branch diode in backward direction, the first branch diode and the second branch diode arranged in series between the apparatus-input and the apparatus-output, with a second central node between them;
• and
• providing a chopper-circuit, arranged between the first central node and the second central node, the chopper-circuit comprising:
• a chopper capacitor, arranged between the first central node and the second central node, and
• a chopper semiconductor, arranged in series with a chopper resistor, this series arranged between the first central node and the second central node,
• so that the sub-circuit comprising the branch diodes and the chopper-circuit is configured for limiting the current in case of a short circuit by leading the current through this sub-circuit;
• setting the apparatus in a normal operation mode, in which the main switch is closed;
• when an overcurrent occurs, setting the apparatus in a current limiting mode, in which the main switch is opened, and a sub-circuit comprising branch diodes and a chopper-circuit mitigates the current in case of a short circuit by leading the current through this sub-circuit, the current limiting mode being performed for a predefined period;
• and
• after the predefined period, setting the apparatus in a fast interruption mode, in which the main switches are open and the chopper-circuit is turned off by turning off the chopper semiconductor Sb.