Apparatus for and method of suppressing power surges utilizing electrical striplines

• US 5,786,974 A
• Filed: 03/12/1997
• Issued: 07/28/1998
• Est. Priority Date: 08/11/1995
• Status: Expired due to Fees

• Current Assignee: Leviton Manufacturing Company Incorporated
• Original Assignee: Leviton Manufacturing Company Incorporated
• Inventors: Zaretsky, Albert
• Primary Examiner(s): Leja, Ronald W.
• Application Number:
  US08/815,759
• Time in Patent Office: 503 Days
• Field of Search: 361/107, 361/110, 361/111, 361/113, 361/118, 361/119, 361/56, 333/128, 333/12, 333/204, 333/81 A, 333/238, 333/246, 333/247, 333/254, 333/260
• US Class Current: 361/107
• CPC Class Codes: H02H 9/044 Physical layout, materials not provided for elsewhere varistors H01C7/12; spark-gaps H01T; Ovshinsky devices H10N70/00

Abstract

A method and apparatus for suppressing surges in an electrical power distribution system utilizing stripline techniques. The apparatus includes an input terminal which connects a phase electrical power source to a TVSS device. A stripline circuit connects the input terminal to the TVSS device to greatly reduce the inductance of the connection. Consequently, the clamping voltage rating of the TVSS device is substantially maintained at the input terminal during the occurrence of a power surge.

Claims

1. A transient voltage surge suppressor circuit, for low frequency, high power applications, comprising:

a) a pair of input terminals for connecting said circuit to a source of electrical power operating at power distribution frequencies and capable of producing transient high current, high power surges and to a circuit requiring low frequency, high power surge suppression protection;

b) surge suppressor means capable of suppressing low frequency, high power surges, electrically coupled to said input terminals for maintaining maximum voltage suppression capability at said input terminals; and

c) at least one stripline conductor pair, capable of conducting low frequency, high power electric surges, electrically interposed between said input terminals and said surge suppressor means such that an inductive reactance present within said stripline conductor pair during low frequency, high power surges is minimized.

2. The device defined by claim 1, wherein said at least one stripline conductor pair comprises as one conductor a copper bar and as a second conductor a length of copper tape, separated by a dielectric.

3. The device defined by claim 1, wherein said surge suppressor means comprises at least one solid state surge suppressor device.

4. The device defined by claim 1, wherein said surge suppressor means comprises at least one gas discharge device.

5. The device defined by claim 3, wherein said solid state surge suppressor device comprises at least one metal oxide varistor.

6. A transient voltage surge suppressor circuit, for low frequency high power applications, comprising:

a) a three phase input terminal for electrical connection to a first, second and third phase port of a three phase electrical power distribution network operating at power distribution frequencies and capable of producing transient high current, high power surges and to an electrical load requiring low frequency, high power surge suppression protection;

b) three phase surge suppressor means capable of suppressing low frequency, high power surges, electrically coupled to said three phase input terminal for maintaining maximum surge suppression at each of said first, second and third phase port; and

c) a three phase electrical stripline circuit, capable of conducting low frequency, high power electric surges, interposed between said three phase surge suppressor means and said three phase input terminal for maintaining minimal inductance between said three phase input terminal and said surge suppressor means.

7. The circuit defined by claim 6, wherein said electrical stripline circuit comprises at least one conductor pair one conductor of said pair being a copper bar and the other conductor a length of copper tape.

8. The circuit defined by claim 6, wherein said surge suppressor means comprises at least one solid state surge suppressor device.

9. The circuit defined by claim 6, wherein said surge suppressor means comprises at least one gas discharge device.

10. The circuit defined by claim 8, wherein said at least one solid state surge suppressor device comprises at least one metal oxide varistor.

11. The circuit defined by claim 6, wherein said electrical stripline circuit comprises three stripline conductor pairs.

12. The circuit defined by claim 6, wherein said three phase surge suppressor means comprises line to neutral and/or line to ground surge suppression.

13. A method of effectively suppressing electrical power surges generated in a source of electrical power, operating at power distribution frequencies and capable of producing transient high current, high power surges, connected to an electrical load, requiring low frequency, high power surge suppression protection, comprising the steps of:

a) providing an input terminal for coupling said source to a surge suppressor device, capable of suppressing low frequency, high power surges, whereby said load may be protected from an overvoltage condition; and

b) electrically coupling said input terminal to said surge suppressor device utilizing electrical stripline techniques such that an inductance inherent in said coupling is minimized, thereby minimizing voltages induced in said stripline during voltage surges, whereby an effective voltage rating characteristic of said device is substantially available at said input terminal.

14. The method defined by claim 13, wherein said source comprises a source of three phase power.

15. The method defined by claim 14, wherein said coupling comprises coupling a three phase input terminal to a three phase surge suppressor device.

16. The method defined by claim 15, wherein said source of three phase power outputs electrical power at first, second and third phases and said three phase surge suppressor device is coupled utilizing a three phase electrical stripline circuit such that a line voltage of each of said first, second and third phases of electrical power are held to an approximate maximum voltage level.

17. A method of suppressing electrical power surges from a source of electrical power, operating at power distribution frequencies and capable of producing transient high current, high power surges, connected across an input load, requiring low frequency, high power surge suppression protection, comprising the steps of:

a) coupling a surge suppressor device, capable of suppressing low frequency high power surges, across one end of a two ended, stripline conductor pair, said stripline conductor pair capable of conducting low frequency, high power surges; and

b) coupling said input load and said source of electrical power across a second end of said stripline conductor pair.

18. A method of suppressing electrical power surges from a three phase electrical power distribution network, operating power distribution frequencies and capable of producing transient high current, high power surges, connected to an input load, requiring low frequency, high power surge suppression protection, comprising the steps of:

a) coupling a three phase surge suppressor device, capable of suppressing low frequency, high power surges, to a three phase stripline circuit, capable of conducting low frequency, high power electric surges, said three phase stripline circuit having two ends, said three phase surge suppressor device coupled at one end of said three phase stripline circuit; and

b) coupling said input load and said three phase electrical power distribution network to a second end of said three phase stripline circuit.