d.c. high-speed circuit-breaker using hybrid technology

摘要

In known d.c. high-speed circuit-breakers using hybrid technology, a semiconductor switch is connected in parallel with a mechanical isolator, onto which semiconductor switch the current is commutated at the moment of switching off so that the mechanical isolator switches virtually in a currentless state. These known hybrid switches have the disadvantage that on the one hand the isolator has to switch very rapidly and on the other hand the commutation sequences have to be coordinated very exactly. The d.c. high-speed circuit-breaker according to the invention using hybrid technology consists of a series circuit of customary isolators (1411 and 1412) between which a thyristor (1415) is arranged. For operational deactivation and fault deactivation, the thyristor (1415) is turned off and the isolators (1411 and 1412) can be opened in a currentless state. In order to ensure that braking energy is fed back, the isolators (1411 and 1412) are bridged by diodes (1413 and 1414) in such a way that a flowing feedback current can also be switched off by the thyristor (1415). The d.c. high-speed circuit-breaker using hybrid technology can be used in all, even in already existing, rectifier distributing substations for supplying power to d.c. railways with a feedback feature while ensuring selectivity. <IMAGE>