System and a protection and remote power-feeding device for equipment connected by two transformers to a four-wire transmission link

• US 4,953,055 A
• Filed: 09/09/1988
• Issued: 08/28/1990
• Est. Priority Date: 09/09/1987
• Status: Expired due to Fees

• Current Assignee: Societe Anonyme DITE Telic Alcatel
• Original Assignee: Societe Anonyme DITE Telic Alcatel
• Inventors: Douhet, Gerard, Daviaud, Yves
• Primary Examiner(s): Pellinen, A. D.
• Assistant Examiner(s): Gaffin, Jeffrey A.
• Application Number:
  US07/242,453
• Time in Patent Office: 718 Days
• Field of Search: 361/62, 361/35, 361/38, 361/250, 361/119, 379/412, 379/413, 379/324
• US Class Current: 361/62
• CPC Class Codes: H04M 19/08 with current supply sources at the substations generating ringing current H04M19/04

Abstract

A remote power-feeding and protection system for equipment connected by two transformers to a four-wire transmission link.

The remote power-feeding and protection system and the remote power-feeding extractor protection device are intended for equipment connected by two transformers to a transmission link with two pairs of wires ensuring remote power-feeding of the fed equipment.

Each transformer is connected to the two wires of one pair by two identical windings serially-connected between these two wires through a capacitor. The two pairs of wires constitute a phantom feed circuit, the two wires of a given pair being connected to the same terminal of a D.C. generator. The extraction and protection device comprises two rectifier bridges each separately connected by their inputs to a pair of wires and interconnected by their outputs in order to provide remote power feeding.

Claims

1. A remote power-feeding and protection system for equipment connected by first and second transformers to to a first end of a transmission link, said transmission link comprising two pairs of wires also providing the remote feeding of power to said equipment from a second end of said transmission link, each said transformer being individually connected to a respective one of said pairs of wires at said first end of said transmission link by first and second coupling means each comprising two identical windings serially connected between the two wires of a respective pair through a capacitor situated between the two windings, and each transformer being also connected by means of at least one winding to said equipment, wherein said remote power feeding and protection system comprises:

a remote power-feeding D.C. generator having a first terminal connected to the two wires of one of the pairs at said second end of the link and a second terminal connected to the two wires of the other of said pairs at said second end of said link, and

a remote power-feeding extractor protection device comprising first and second rectifier bridges, said first rectifier bridge having two inputs connected to the terminals of the capacitor of said first coupling means and said second rectifier bridge having two inputs connected to the terminals of the capacitor of said second coupling means, and said first and second bridge rectifiers having their output terminals connected in parallel for supplying power to said equipment.

2. A remote power feeding extractor protection device for equipment connected by first and second transformers to one end of a transmission link, said transmission link comprising two pairs of wires which also feed power to said equipment from the other end of said transmission link by a D.C. voltage applied between the two pairs of wires, each transformer being individually connected to a respective one of said pairs of wires by respective first and second coupling means each comprising two identical windings serially connected between the two wires of the respective pair through a capacitor situated between the two windings, and each said transformer being connected by at least one winding to the fed equipment, wherein said remote power feeding extractor protection device comprises:

first and second rectifier bridges, said first rectifier bridge having two input terminals connected to the terminals of the capacitor of said first coupling means and said second rectifier bridge having two inputs connected to the terminals of the capacitor of said second coupling means, and said first and second rectifier bridges having their output terminals connected in parallel for supplying power to said equipment.

3. A remote power-feeding extractor protection device as defined in claim 2, wherein the rectifier bridges each comprise first and second diodes connected in series with a cathode of said first diode connected to an anode of said second diode at a first common point, third and fourth diodes connected in series with a cathode of said third diode connected to an anode of said fourth diode at a second common point, and with anodes of said first and third diodes being connected at a third common point and cathodes of said second and fourth diodes being connected at a fourth common point, with bridge inputs being taken from said first and second common points and bridge outputs being taken from said third and fourth common points.