Traveling waves for selective underground fault interruption

Patent metadata

Field	Value
Publication number	US-2024332921-A1
Application number	US-202418438737-A
Country	US
Kind code	A1
Filing date	Feb 12, 2024
Priority date	Mar 31, 2023
Publication date	Oct 3, 2024
Grant date	—

Abstract

An underground power distribution network that clears faults using detected traveling waves. The network includes a power source, a feeder receiving power from the power source, and a plurality of series connected switchgear disposed along the feeder. Each switchgear includes at least one current interrupting device for interrupting current on the feeder, at least one current sensor for measuring current on the feeder, and a controller responsive to current measurement signals from the current sensor. A communications link provides communications between the controllers. The current sensors detect traveling waves as a result of a fault on the feeder and the controllers broadcast messages on the communications link identifying whether the controller receives positive polarity or negative polarity traveling waves that identify whether the fault is downstream or upstream of the switchgear so as to determine which current interrupting device will be opened to clear the fault.

First claim

What is claimed is:

1 . A power distribution network comprising:
a power source: a main power line receiving power from the power source; a plurality of switchgear disposed along and electrically coupled to the main power line, each switchgear including at least one current interrupting device for interrupting current on the main power line, at least one current sensor for measuring current on the main power line, and a switchgear controller responsive to current measurement signals from the at least one current sensor; and a communications link providing communications between the switchgear controllers in the plurality of switchgear, wherein the at least one current sensor in the plurality of switchgear detects traveling waves as a result of a fault on the main power line and the switchgear controllers broadcast messages on the communications link identifying whether the switchgear controller receives positive polarity or negative polarity traveling waves that identify whether the fault is downstream or upstream of the switchgear so as to determine which current interrupting device will be opened to clear the fault.

2 . The network according to claim 1 further comprising a central controller, wherein the switchgear controllers provide messages to the central controller identifying when the at least one current sensor detects a traveling wave and its polarity, the central controller instructing one of the switchgear controllers to open at least one of the current interrupting devices based on when the traveling waves are detected and their polarity.

3 . The network according to claim 1 wherein one of the switchgear controllers is a master controller, and wherein the switchgear controllers provide messages to the master controller identifying when the at least one current sensor detects a traveling wave and its polarity, the master controller instructing one of the switchgear controllers to open at least one of the current interrupting devices based on when the traveling waves are detected and their polarity.

4 . The network according to claim 1 wherein the main power line is a three-phase power line and each switchgear includes at least one current interrupting device for each phase and a current sensor for each current interrupting device, and wherein the at least one current interrupting device to be opened to clear the fault depends on which phase is affected by the fault.

5 . The network according to claim 4 wherein each switchgear includes an upstream current interrupting device and a downstream current interrupting device for each phase.

6 . The network according to claim 1 further comprising a plurality of lateral lines tapped off of the main power line in each switchgear, each switchgear further including a current interrupting device or a fuse and a current sensor for each lateral line, the current sensor for each lateral line detecting traveling waves from a fault on the lateral line, wherein the switchgear controller opens the current interrupting device or allows the fuse to operate on the lateral line if it detects a traveling wave on that lateral line so that other current interrupting devices in the network don't open.

7 . The network according to claim 1 wherein the network is an underground power distribution network.

8 . The network according to claim 1 wherein the communications link is a fiber optics link.

9 . The network according to claim 1 wherein the current sensors are current transformers.

10 . The network according to claim 1 wherein the plurality of switchgear is more than three switchgear.

11 . An underground power distribution network comprising:
a power source: a three-phase feeder receiving power from the power source; a plurality of switchgear disposed along and electrically coupled to the feeder, each switchgear including at least one current interrupting device for each phase for interrupting current on the feeder, a current sensor for each current interrupting device for measuring current on the feeder, and a switchgear controller responsive to current measurement signals from the current sensors in the switchgear; and a communications link providing communications between the switchgear controllers in the plurality of switchgear, wherein the current sensors in the plurality of switchgear detect traveling waves as a result of a fault on the feeder and the switchgear controllers broadcast messages on the communications link identifying whether the switchgear controller receives positive polarity or negative polarity traveling waves that identify whether the fault is downstream or upstream of the switchgear so as to determine which current interrupting device will be opened to clear the fault.

12 . The network according to claim 11 further comprising a central controller, wherein the switchgear controllers provide messages to the central controller identifying when the current sensors detect a traveling wave and its polarity, the central controller instructing one of the switchgear controllers to open at least one of the current interrupting devices based on when the traveling waves are detected and their polarity.

13 . The network according to claim 11 wherein one of the switchgear controllers is a master controller, and wherein the switchgear controllers provide messages to the master controller identifying when the current sensors detect a traveling wave and its polarity, the master controller instructing one of the switchgear controllers to open at least one of the current interrupting devices based on when the traveling waves are detected and their polarity.

14 . The network according to claim 11 wherein each switchgear includes an upstream current interrupting device and a downstream current interrupting device for each phase.

15 . The network according to claim 11 further comprising a plurality of lateral lines tapped off of the feeder in each switchgear, each switchgear further including a current interrupting device or a fuse and a current sensor for each lateral line, the current sensor for each lateral line detecting traveling waves from a fault on the lateral line, wherein the switchgear controller opens the current interrupting device or allows the fuse to operate on the lateral line if it detects a traveling wave on that lateral line so that other current interrupting devices in the network don't open.

16 . The network according to claim 11 wherein the plurality of switchgear is more than three switchgear.

17 . An underground power distribution network comprising:
a power source: a three-phase feeder receiving power from the power source; a plurality of switchgear disposed along and electrically coupled to the feeder; a plurality of lateral lines tapped off of the feeder in each switchgear, each switchgear including an upstream current interrupting device and a downstream current interrupting device for each phase for interrupting current on the feeder, a current interrupting device or a fuse for each lateral line, a current sensor for each current interrupting device or fuse for measuring current on the feeder and the lateral lines, and a switchgear controller responsive to current measurement signals from the current sensors in the switchgear; and a communications link providing communications between the switchgear controllers in the plurality of switchgear, wherein the current sensors in the plurality of switchgear detect traveling waves as a result of a fault on the feeder or a lateral line and the switchgear controllers broadcast messages on the communications link identifying wh

Assignees

• S & C Electric Co

Inventors

• French John

Classifications

• H02G9/00

  Installations of electric cables or lines in or on the ground or water · CPC title

• H02B1/202 Primary

  Cable lay-outs · CPC title