Single-pole, single current path switching system and method

Patent metadata

Field	Value
Publication number	US-9726726-B2
Application number	US-201514832861-A
Country	US
Kind code	B2
Filing date	Aug 21, 2015
Priority date	Nov 6, 2014
Publication date	Aug 8, 2017
Grant date	Aug 8, 2017

Abstract

One embodiment describes a three-phase electromechanical switching device, which includes three single-phase switching devices mechanically and electrically coupled in parallel with one another, each single-phase switching device including a direct current electromagnetic operator that in operation receives a direct current control signal for switching of the device, stationary contacts disposed in a respective device housing, and a movable assembly that in operation is displaced by energizing the operator and that include movable contacts that open and close, with the stationary contacts, a single current carrying path through the respective single-phase switching device; in which each of the single-phase switching devices receives control signals from control circuitry coupled to the operators of the respective single-phase switching devices to cause at least one of the single-phase switching devices to open or close the single current carrying path at a desired time coordinated with a current zero-crossing or a predicted current zero-crossing of a phase of three-phase power.

First claim

The invention claimed is:

1. A three-phase electromechanical switching device, comprising:
three single-phase switching devices mechanically and electrically coupled in parallel with one another, each single-phase switching device comprising a direct current electromagnetic operator that in operation receives a direct current control signal for switching of the device, stationary contacts disposed in a respective device housing, and a movable assembly that in operation is displaced by energizing the operator and that comprises movable contacts that open and close, with the stationary contacts, a single current carrying path through the respective single-phase switching device;
wherein each of the single-phase switching devices is configured to receive control signals from control circuitry coupled to the operators of the respective single-phase switching devices to cause at least one of the single-phase switching devices to open or close the single current carrying path at a desired time coordinated with a current zero-crossing or a predicted current zero-crossing of a phase of three-phase power
wherein each single-phase switching device comprises a direct current electromagnetic operator that in operation receives a direct current control signal for switching of the device, stationary contacts disposed in a device housing, and a movable assembly that in operation is displaced by energizing the operator, and that comprises movable contacts that, with the stationary contacts, open and close a single current carrying path through the respective single-phase switching device, wherein a gap is provided between a core of the operator and an armature of the movable assembly when the movable assembly is displaced to a closed position;
wherein each single-phase switching device comprises a plurality of splitter plates disposed adjacent to the movable contacts and configured to:
cool hot gas and plasma during operation of the device; and
break an arc generated during operation of the device into smaller arcs;
wherein the device housing comprises an interior surface having venting channels adjacent to the splitter plates for channeling the hot gas and plasma.

2. The three-phase electromechanical switching device of claim 1 , wherein each single current carrying path comprises a single line-side conductor, a single load-side conductor, stationary and movable contacts, and a movable conductor movable with the movable contacts.

3. The three-phase electromechanical switching device of claim 1 , wherein the direct current electromagnetic operator of each of the three single-phase switching devices comprises:
a generally U-shaped yoke; and
a generally cylindrical core disposed in the yoke and secured to the yoke.

4. The three-phase electromechanical switching device of claim 1 , wherein the core of each of the three single-phase switching devices comprises an aperture configured to receive an alignment pin extending from the armature.

5. The three-phase electromechanical switching device of claim 4 , comprising a return spring disposed around the alignment pin to urge the movable assembly towards an open position.

6. The three-phase electromechanical switching device of claim 1 , wherein the gap comprises an air gap.

7. The three-phase electromechanical switching device of claim 1 , wherein each single current carrying path comprises a single line-side conductor, a single load-side conductor, stationary and movable contacts, and a movable conductor movable with the movable contacts.

8. A three-phase electromechanical switching device, comprising:
a first single-phase switching device comprising a first direct current electromagnetic operator that in operation receives a first direct current control signal to control switching of the first single-phase switching device, first stationary contacts disposed in a first device housing of the first single-phase switching device, a first movable assembly comprising first movable contacts disposed in the first device housing, and a first plurality of splitter plates disposed adjacent to the first movable contacts, wherein:
the first single-phase switching device is configured to, based at least in part on the first direct current control signal:
actuate the first movable assembly to electrically connect the first movable contacts with the first stationary contacts to close a first single current carrying path through the first single-phase switching device; and
actuate the first movable assembly to electrically disconnect the first movable contacts from the first stationary contacts to open the first single current carrying path;

the first plurality of splitter plates is configured to:
cool hot gas and plasma produced during operation of the first single-phase switching device, wherein the first device housing comprises a first interior surface with first venting channels adjacent to the first plurality of splitter plates configured to channel hot gas and plasma produced during operation of the first single-phase switching device; and
break a first arc generated during operation of the first single-phase switching device into smaller arcs;

a second single-phase switching device comprising a second direct current electromagnetic operator that in operation receives a second direct current control signal that controls switching of the second single-phase switching device, second stationary contacts disposed in a second device housing of the second single-phase switching device, a second movable assembly comprises second movable contacts disposed in the second device housing, and a second plurality of splitter plates disposed adjacent to the second movable contacts, wherein:
the second single-phase switching device is configured to, based at least in part on the second direct current control signal:
actuate the second movable assembly to electrically connect the second movable contacts with the second stationary contacts to close a second single current carrying path through the second single-phase switching device; and
actuate the second movable assembly to electrically disconnect the second movable contacts from the second stationary contacts to open the second single current carrying path; and

the second plurality of splitter plates is configured to:
cool hot gas and plasma produced during operation of the first single-phase switching device, wherein second device housing comprises a second interior surface with second venting channels adjacent to the second plurality of splitter plates configured to channel hot gas and plasma produced during operation of the second single-phase switching device; and
break a second arc generated during operation of the second single-phase switching device into smaller arcs;

a third single-phase switching device comprising a third direct current electromagnetic operator that in operation receives a third direct current control signal that controls switching of the third single-phase switching device, third stationary contacts disposed in a third device housing of the third single-phase switching device, a third movable assembly comprises third movable contacts disposed in the third device housing, and a third plurality of splitter plates disposed adjacent to the third movable contacts, wherein:
the third single-phase switching device is configured to, based at least in part on the third direct current control signal:
actuate the third movable assembly to electrically connect the third movable contacts with the third stationary contacts to close a third single current carrying path through the third single-phase switching device; and
actuate the third movable assembly to electrically disconnect the third movable contacts from the third stationary contacts to open the third sin

Assignees

• Rockwell Automation Tech Inc

Inventors

• Bock Christopher H
• Wieloch Christopher J
• Kinsella James J
• Dziekonski Stefan T

Classifications

• H01H50/38

  Part of main magnetic circuit shaped to suppress arcing between the contacts of the relay · CPC title

• G01R31/327 Primary

  Testing of circuit interrupters, switches or circuit-breakers · CPC title

• H02P1/32

  by star/delta switching · CPC title

• G01K7/00

  Measuring temperature based on the use of electric or magnetic elements directly sensitive to heat (giving results other than momentary value of temperature G01K3/00) {; Power supply therefor, e.g. using thermoelectric elements} · CPC title

• H02P1/26

  for starting an individual polyphase induction motor · CPC title