System and method for point on wave closing of a vacuum interrupter

Patent metadata

Field	Value
Publication number	US-12444558-B2
Application number	US-202318483133-A
Country	US
Kind code	B2
Filing date	Oct 9, 2023
Priority date	Nov 8, 2022
Publication date	Oct 14, 2025
Grant date	Oct 14, 2025

Abstract

A system and method for point on wave closing of a switching device, where the close initiation point is selected so that a minor current loop is generated that minimizes the accumulated current during the closing operation. The method includes determining bounce characteristic of contacts in the switching device during the closing operation, identifying available close initiation points on a voltage wave for a voltage across the contacts, selecting one or two of the close initiation points on the voltage wave that minimizes the accumulation of current during the closing operation, and closing the switching device using the selected close initiation point.

First claim

What is claimed is:

1. A method for closing contacts in a switching device during a switching device closing operation, the method comprising:
determining bounce characteristic of the contacts during the closing operation;
identifying available close initiation points on a voltage wave for a voltage across the contacts;
selecting close initiation points from a plurality of possible close initiation points on the voltage wave that minimizes the accumulation of current during the closing operation; and
closing the switching device using the selected close initiation point.

2. The method according to claim 1 wherein the selected close initiation points generates a minor current loop of a current wave during the closing operation.

3. The method according to claim 2 wherein the current wave is caused by fault current.

4. The method according to claim 1 wherein the switching device includes a vacuum interrupter that has the contacts.

5. The method according to claim 4 wherein the switching device includes a magnetic actuator that controls the vacuum interrupter.

6. The method according to claim 5 wherein selecting close initiation points includes considering the response time of the magnetic actuator.

7. The method according to claim 5 wherein the switching device is associated with a transformer in an electrical circuit.

8. A method for closing contacts in a vacuum interrupter during a closing operation, the vacuum interrupter being controlled by a magnetic actuator, the method comprising:
determining bounce characteristic of the contacts during the closing operation;
determining a response of the magnetic actuator from the time being commanded closed and closing the contacts;
identifying available close initiation points on a voltage wave for a voltage across the contacts;
selecting one or two of the close initiation points on the voltage wave using the bounce characteristics and the actuator response that minimizes accumulation of current during the closing operation; and
closing the vacuum interrupter using the selected close initiation point.

9. The method according to claim 8 wherein the selected one of the close initiation points generates a minor current loop of a current wave during the closing operation.

10. The method according to claim 9 wherein the current wave is caused by fault current.

11. The method according to claim 8 wherein the vacuum interrupter is associated with a transformer in an electrical circuit.

Assignees

• S & C Electric Co

Inventors

• Porter David G
• Kelley Thomas S
• Milton Joseph W
• Berman Andrew B

Classifications

• H01H33/6662 Primary

  using bistable electromagnetic actuators, e.g. linear polarised electromagnetic actuators · CPC title

• H01H2009/566

  with self learning, e.g. measured delay is used in later actuations · CPC title

• H01H2033/6668

  with a plurality of interruptible circuit paths in single vacuum chamber · CPC title

• H01H9/56

  for ensuring operation of the switch at a predetermined point in the AC cycle · CPC title

• H01H33/593 Primary

  for ensuring operation of the switch at a predetermined point of the AC cycle (for multipolar switches H01H9/563) · CPC title