| 摘要 |
<p>PCT No. PCT/FR96/00587 Sec. 371 Date Oct. 3, 1997 Sec. 102(e) Date Oct. 3, 1997 PCT Filed Apr. 18, 1996 PCT Pub. No. WO96/33542 PCT Pub. Date Oct. 24, 1996A differential protection device includes a current transformer comprising a toroid formed by a magnetic core, primary windings formed by the active conductors of the installation and a secondary winding at the terminals of which a differential fault signal is established when a differential fault occurs in the primary windings, a tripping relay of a current breaking apparatus, and a secondary connection circuit connecting the relay to the terminals of the secondary winding, the secondary connection circuit being arranged to bring about tripping when the signal exceeds a preset threshold. The above-mentioned secondary circuit comprises a full-wave rectifier and a capacitor, connected in parallel with the secondary winding of the toroid, and the magnetic core is made of a nanocrystalline material.</p> |
