High voltage compact fuse assembly with magnetic arc deflection

Patent metadata

Field	Value
Publication number	US-9899180-B2
Application number	US-201615388438-A
Country	US
Kind code	B2
Filing date	Dec 22, 2016
Priority date	Mar 23, 2015
Publication date	Feb 20, 2018
Grant date	Feb 20, 2018

Abstract

Fuse assemblies in the form of fuse blocks and fuse holders include embedded permanent magnet arc suppression features that facilitate higher voltage operation of fusible circuit protection without increasing the size of the fuse assemblies. The embedded magnets apply an external magnetic field upon an overcurrent protection fuse and produce an arc deflection force to enhance arc quenching capability of the fuse without increasing its form factor.

First claim

What is claimed is:

1. A circuit protection device for an electrical power system, the circuit protection device assembly comprising:
a nonconductive housing defining a fuse receptacle dimensioned to receive an overcurrent protection fuse, wherein the overcurrent protection fuse includes first and second conductive fuse terminal elements and a fuse element assembly therebetween;
a first resilient fuse clip and a second resilient fuse clip coupled to the nonconductive housing, each of the first resilient fuse clip and the second resilient fuse clip configured to receive a respective one of the first and second conductive fuse terminal elements of the overcurrent protection fuse;
at least one set of line and load-side terminals accessible from an exterior of the nonconductive housing and configured to connect to external circuitry in the electrical power system; and
a magnetic arc suppression system in the nonconductive housing and imposing a magnetic field in the fuse receptacle.

2. The circuit protection device of claim 1 , wherein the overcurrent protection fuse has a longitudinal axis, and wherein the magnetic arc suppression system imposes a magnetic field extending in a direction parallel to the longitudinal axis when the overcurrent protection fuse is received in the fuse receptacle.

3. The circuit protection device of claim 1 , wherein the overcurrent protection fuse has a longitudinal axis, and wherein the magnetic arc suppression system imposes a magnetic field extending in a direction perpendicular to the longitudinal axis when the overcurrent protection fuse is received in the fuse receptacle.

4. The circuit protection device of claim 1 , wherein the fuse element assembly includes a short circuit element and an overload element connected in series between the first and second conductive fuse terminal elements, the magnetic field being imposed on each of the short circuit element and the overload element when the overcurrent protection fuse is received in the fuse receptacle.

5. The circuit protection device of claim 4 , wherein the magnetic arc suppression system is sufficient to cool electrical arcing when one of the short circuit element and overload elements in the overcurrent protection fuse opens under an operating voltage of the electrical power system of greater than 600 VDC.

6. The circuit protection device of claim 5 , wherein the magnetic arc suppression system is sufficient to cool electrical arcing when one of the short circuit element and overload elements in the overcurrent protection fuse opens under an operating voltage up to 1500 VDC.

7. The circuit protection device of claim 1 , wherein the magnetic arc suppression system is substantially covered by the overcurrent protection fuse when the overcurrent protection fuse is received in the fuse receptacle.

8. The circuit protection device of claim 1 , wherein the magnetic arc suppression system comprises a ferromagnetic plate and at least one permanent magnet.

9. The circuit protection device of claim 8 , wherein the ferromagnetic plate is U-shaped.

10. The circuit protection device of claim 1 , wherein the nonconductive housing is configured as an open style fuse block having a plurality of fuse receptacles, and the magnetic arc suppression system imposing a magnetic field in multiple ones of the plurality of fuse receptacles.

11. The circuit protection device of claim 10 , wherein the magnetic arc suppression system includes a plurality of permanent magnets, and at least one of the plurality of permanent magnets is mutually shared by first and second ones of the plurality of fuse receptacles to establish a magnetic field in each of the first and second ones of the plurality of fuse receptacles.

12. The circuit protection device of claim 11 , further comprising a movable switch contact provided in the nonconductive housing to connect or disconnect a circuit path in the nonconductive housing.

13. The circuit protection device of claim 12 , wherein the circuit protection device further comprises a cap covering a longitudinal end of the fuse receptacle.

14. A circuit protection device of comprising:
a nonconductive housing defining at least one elongated fuse receptacle dimensioned to receive a cylindrical overcurrent protection fuse including opposing end caps and a fuse element assembly;
a first resilient fuse clip and a second resilient fuse clip spaced apart from one another in the nonconductive housing, each of the first resilient fuse clip and the second resilient fuse clip configured to receive a respective one of the opposing end caps of the cylindrical overcurrent protection fuse;
at least one set of line and load-side terminals provided in the nonconductive housing and configured to be connected to external circuitry in the electrical power system having an operating system voltage of greater than 600 VDC; and
a magnetic arc suppression system including at least one permanent magnet coupled to the nonconductive housing and imposing a magnetic field in the at least one elongated fuse receptacle and across the fuse element assembly to cool electrical arcing when the fuse element opens.

15. The circuit protection device of claim 14 , wherein the magnetic arc suppression system further includes at least one ferromagnetic plate proximate the at least one permanent magnet.

16. The circuit protection device of claim 14 , wherein the nonconductive housing defines an open style fuse block.

17. The circuit protection device of claim 14 , wherein the arc suppression system cools electrical arcing when the fuse element opens at an operating system voltage of 1000 VDC.

18. The circuit protection device of claim 14 , wherein the arc suppression system cools electrical arcing when the fuse element opens at an operating system voltage of 1500 VDC.

19. The circuit protection device of claim 14 , wherein the fuse element assembly includes a short circuit element and an overload element connected in series between the first and second conductive fuse terminal elements, the magnetic field being imposed on each of the short circuit element and the overload element.

20. A circuit protection device comprising:
a nonconductive housing defining one of a fuse block and a fuse holder, the nonconductive housing including at least one pair of opposed side walls defining at least one elongated fuse receptacle therebetween, the at least one elongated fuse receptacle dimensioned to receive a cylindrical overcurrent protection fuse including opposing end caps and a fuse element assembly;
at least one set of resilient fuse clips configured to receive the opposing end caps and establish an electrical connection through the fuse element assembly;
at least one set of line and load-side terminals provided in the nonconductive housing and configured for connection to external circuitry in the electrical power system having an operating system voltage of at least about 1000 VDC; and
a magnetic arc suppression system located in the elongated fuse receptacle and imposing an external magnetic field across the fuse element assembly, whereby current flowing through the fuse element assembly and through the external magnetic field produces a mechanical arc deflection force when the fuse element assembly operates to interrupt the electrical connection through the least one fusible element.

Assignees

• Cooper Technologies Co

Inventors

• Zhou Xin
• Douglass Robert Stephen
• Saporita Vincent John

Classifications

• H01H85/205

  Electric connections to contacts on the base · CPC title

• H01H85/50

  the fuse having contacts at opposite ends for co-operation with the base · CPC title

• H01H85/38 Primary

  Means for extinguishing or suppressing arc (by powder filling H01H85/18; by mechanical tension applied to fusible member H01H85/36) · CPC title

• H01H2085/386

  with magnetic or electrodynamic arc-blowing · CPC title

• H01H85/202

  for fuses with ferrule type end contacts · CPC title