| 摘要 |
The invention relates to a current limiting device comprising a high temperature supraconductor which is accommodated in a cryostat filled with liquid nitrogen, whereby the current limiting device is connected in series to a switching unit in a network for supplying and distributing power, especially in the medium high voltage range. Said switching unit can be controlled by a trigger signal in order to interrupt the power supply in the excess current range. A light-emitting diode (LD) is connected in parallel to the high temperature supraconductor (SL) and forms a series connection with a starting resistor (RV) and optionally with a bi-directional rectifier (DG), whereby the optical signal (ES) of the light-emitting diode (LD) is transmitted over an optical waveguide (LWL) to a photodiode (PD), and the photodiode (PD) influences a transimpedance amplifier (IV), said amplifier being connected in outgoing circuit, in the excess current range such that the transimpedance amplifier generates the trigger signal (AS) for the switching unit (SG). Current limiting devices of this type are used as protective elements to protect against excess currents in networks for supplying and distributing power.
|
