Apparatus and method for isolating a trigger circuit of a silicon-controlled rectifier

• US 6,417,719 B1
• Filed: 02/28/2001
• Issued: 07/09/2002
• Est. Priority Date: 03/01/2000
• Status: Active Grant

• Current Assignee: Electric Power Research Institute Incorporated
• Original Assignee: Electric Power Research Institute Incorporated
• Inventors: Deam, David R.
• Primary Examiner(s): Zweizig, Jeffrey
• Application Number:
  US09/797,265
• Time in Patent Office: 496 Days
• Field of Search: 327/438, 327/439, 327/445, 327/446, 327/453, 327/454, 327/455, 327/456, 327/457, 327/458, 327/459, 327/460, 327/468, 327/475
• US Class Current: 327/438
• CPC Class Codes: G02B 6/43 Arrangements comprising a plurality of opto-electronic elements and associated optical interconnections
• CPC Class Codes: H03K 17/08144 in thyristor switches
• CPC Class Codes: H03K 17/79 controlling bipolar semiconductor switches with more than two PN-junctions, or more than three electrodes, or more than one electrode connected to the same conductivity region
• CPC Class Codes: H03K 2217/0036 Means reducing energy consumption

Abstract

An apparatus for isolating driver circuits from silicon-controlled rectifier (SCR) circuits in an electric switch. The driver circuits are located on a driver-board, which includes an infrared (IR) emitter. The SCR circuits are located on a SCR switch-board, which includes an IR receiver. An insulating body is positioned between the driver-board and the switch-board. The insulating body encloses a light-pipe to optically link the infrared emitter to the infrared detector. Control signals can be communicated from the driver circuits to the SCR circuits via the IR emitter, the light-pipe, and the IR receiver.

Claims

1. An apparatus for providing voltage isolation between a driver circuit and a silicon-controlled rectifier control circuit, comprising:

a first circuit board supporting an optical emitter that is coupled to the driver circuit;

a second circuit board supporting an optical detector that is coupled to the silicon-controlled rectifier control circuit; and

an insulating body interposed between the first circuit board and the second circuit board, the insulating body enclosing a light conductor to provide an optical link between the optical emitter and the optical detector and to enable communications between the driver circuit and the silicon-controlled rectifier control circuit via the optical link.

2. The apparatus of claim 1, wherein the insulating body rigidly affixes the first circuit board to the second circuit board.

3. The apparatus of claim 1, wherein the optical emitter comprises an infrared emitter.

4. The apparatus of claim 1, wherein the optical detector comprises an infrared detector.

5. The apparatus of claim 1, wherein the silicon-controlled rectifier control circuit comprises a MOSFET silicon-controlled rectifier gate trigger circuit.

6. The apparatus of claim 1, wherein the second circuit board comprises a silicon-controlled rectifier circuit.

7. The apparatus of claim 1, wherein the second circuit board comprises a snubber capacitor coupled to the silicon-controlled rectifier control circuit.

8. The apparatus of claim 1, wherein the second circuit board comprises a varistor.

9. The apparatus of claim 1, wherein the light conductor comprises a light-pipe.

10. The apparatus of claim 1, wherein the insulating body comprises polycarbonate.

11. An apparatus for providing voltage isolation between a driver circuit and a silicon-controlled rectifier control circuit, comprising:

a first circuit board supporting an infrared emitter that is coupled to the driver circuit;

a second circuit board supporting an infrared detector that is coupled to the silicon-controlled rectifier control circuit, the second circuit board further supporting a silicon-controlled rectifier circuit coupled to the silicon-controlled rectifier control circuit, the silicon-controlled rectifier control circuit comprising a MOSFET silicon-controlled rectifier gate trigger circuit; and

an insulating body interposed between and rigidly affixed to the first circuit board and the second circuit board, the insulating body enclosing a light-pipe to provide an optical link between the infrared emitter and the infrared detector and to enable communications between the driver circuit and the silicon-controlled rectifier control circuit via the optical link.

12. An apparatus for providing voltage isolation between a plurality of driver circuits and a plurality of silicon-controlled rectifier control circuits, comprising:

a first circuit board supporting a plurality of optical emitters that are coupled to the plurality of driver circuits;

a second circuit board supporting a plurality of optical detectors that are coupled to the plurality of silicon-controlled rectifier control circuits; and

a plurality of insulating bodies interposed between the first circuit board and the second circuit board, the insulating bodies enclosing a plurality of light conductors to provide optical links between the optical emitters and the optical detectors and to enable communications between the driver circuits and the silicon-controlled rectifier control circuits via the optical links.

13. The apparatus of claim 12, wherein the insulating bodies rigidly affix the first circuit board to the second circuit board.

14. The apparatus of claim 12, wherein the optical emitters comprise infrared emitters.

15. The apparatus of claim 12, wherein the optical detectors comprise infrared detectors.

16. The apparatus of claim 12, wherein the silicon-controlled rectifier control circuits comprise MOSFET silicon-controlled rectifier gate trigger circuits.

17. The apparatus of claim 12, wherein the second circuit board comprises silicon-controlled rectifier circuits.

18. The apparatus of claim 12, wherein the second circuit board comprises snubber capacitors coupled to the silicon-controlled rectifier control circuits.

19. The apparatus of claim 12, wherein the second circuit board comprise varistors.

20. The apparatus of claim 12, wherein the light conductors comprise light-pipes.

21. The apparatus of claim 12, wherein the insulating bodies comprise polycarbonate.