| 摘要 |
<p>The present invention is concerned with maintaining the power supply to equipments along at least a section of a transmission line in the event of said line being cut. Each equipment (5) along the line (1) is provided with a local power supply circuit (6,7,9) inserted in the remote power supply loop at the equipment under consideration. A looping impedance (10) is connected in series with the break contacts (11,12) of a controlled switch and parallel across the power supply loop in such a manner as to create a partial power supply loop through the local power supply circuit when the switch is closed. Control means are provided to close the switch in the event of a power failure in the local power supply circuit, and to open the switch again only once the downstream side of the power supply loop draws current above a predetermined threshold value. The above circuit operates for a power supply loop that includes an energy source at one end (E) only of the transmission line. A variant embodiment of the invention operates in a transmission line where power may be drawn from either end. The invention is applicable to transmission circuits that include at least one branch of a point to point connection.</p> |
