High tension network distribution system

Claim 2

A high tension network distribution system which comprises a plurality of high voltage feeders connected to each other in a net-type for carrying electric power of commercial frequency; a plurality of distribution transformers each connected to the feeding point of each of said feeders; a feeder breaker provided at the end of each of said feeders adjacent to its associated substation; a protector breaker provided at the end of each of said feeders adjacent to its feeding point; a carrier signal transmitter adapted to apply a zero-phase-sequence carrier signal having a frequency different from said commercial frequency across said feeders and ground; an insulating transformer for transmitting said electric power of commercial frequency between adjacent ones of said feeders, but not for transmitting said zero-phase-sequence carrier signal between the adjacent feeders; and a plurality of signal receivers each adapted to receive said zero-phase-sequence carrier signal from the associated feeder, said protector breaker including relay means for closing the corresponding breaker when said corresponding rEceiver receives said carrier signal and for opening the breaker when the receiver does not receive said carrier signal.

Claim 3

The system as set forth in claim 1, in which said insulating transformer has a first winding connected to one of said adjacent feeders and a second winding connected to the other of the adjacent feeders and said first and second windings are magnetically bonded to each other.

Claim 4

The system as set forth in claim 2, in which said first and second windings of the insulating transformer have the same number of turns.

Claim 5

The system as set forth in claim 2, in which said first and second windings of the insulating transformer have taps mounted thereon and said taps on the first and second windings are so selected that difference between impedances as seen on the opposite sides of said transformer can be compensated for.

Claim 6

A high tension network distribution system which comprises a plurality of high voltage feeders connected to each other in a net-type for carrying electric power of commercial frequency, said feeders being connected to a common substation; a feeder breaker provided at the end of each of said feeders adjacent to said substation; a protector breaker provided at the end of each of said feeders adjacent to its feeding point; a carrier signal transmitter adapted to apply zero-phase-sequence carrier signal different from said commercial frequency across said feeders and ground; an insulating transformer connected between adjacent ones of said feeders for transmitting said electric power of commercial frequency between said adjacent feeders, but not for transmitting said zero-phase-sequence carrier signal between the adjacent feeders; and a plurality of signal receivers each adapted to receive said zero-phase-sequence carrier signal from the associated feeder, said protector breaker including relay means for closing the corresponding breaker when the corresponding receiver receives said carrier signal and for opening the breaker when the receiver does not receive the carrier signal.

Claim 7

A high tension network distribution system which comprises a plurality of high voltage feeders connected to each other in a net-type for carrying electric power of commercial frequency, said feeders being connected to a common substation; a feeder breaker provided at the end of each of said feeders adjacent to said substation; a protector breaker provided at the end of each of said feeders adjacent to its feeding point; a carrier signal transmitter adapted to apply zero-phase-sequence carrier signal different from said commercial frequency across said feeders and ground; an insulating transformer connected between adjacent ones of said feeders for transmitting said electric power of commercial frequency between said adjacent feeders, but not for transmitting said zero-phase-sequence carrier signal between the adjacent feeders; and a plurality of signal receivers each adapted to receive said zero-phase-sequence carrier signal from the associated feeder, said protector breaker including relay means for closing the corresponding breaker when the corresponding receiver receives said carrier signal and for opening the breaker when the receiver does not receive the carrier signal.

Claim 8

A high tension network distribution system which comprises a plurality of feeders connected to each other in a net-type for carrying electric power of commercial frequency, adjacent ones of said feeders being connected to different substantions; a feeder breaker provided at the end of each of said feeders adjacent to the associated substation; a protector breaker provided at the end of each of said feeders adjacent to its feeding point; a carrier signal transmitter adapted to apply zero-phase-sequence carrier signal having a frequency different from said commercial frequency across said feeders and ground; an insulating transformer connected between adjacent ones of said feeders for transmitting said electric power of commercial frequency between adjacent ones of said feeders, but not for transmitting said zero-phase-sequence carrier signal between the adjacent feeders; and a plurality of signal receivers each adapted to receive said zero-phase-sequence carrier signal from the associated feeders, said protector breaker including relay means for closing the corresponding breaker when said corresponding receiver receives said carrier signal and for opening the breaker when the receiver does not receive the carrier signal.

Claim 9

A high tension network distribution system which comprises a plurality of feeders connected to each other in a net-type for carrying electric power of commercial frequency, adjacent ones of said feeders being connected to different substantions; a feeder breaker provided at the end of each of said feeders adjacent to the associated substation; a protector breaker provided at the end of each of said feeders adjacent to its feeding point; a carrier signal transmitter adapted to apply zero-phase-sequence carrier signal having a frequency different from said commercial frequency across said feeders and ground; an insulating transformer connected between adjacent ones of said feeders for transmitting said electric power of commercial frequency between adjacent ones of said feeders, but not for transmitting said zero-phase-sequence carrier signal between the adjacent feeders; and a plurality of signal receivers each adapted to receive said zero-phase-sequence carrier signal from the associated feeders, said protector breaker including relay means for closing the corresponding breaker when said corresponding receiver receives said carrier signal and for opening the breaker when the receiver does not receive the carrier signal.