Solid state circuit breaker using RB-IGCTS

Patent metadata

Field	Value
Publication number	US-11264790-B2
Application number	US-201916707426-A
Country	US
Kind code	B2
Filing date	Dec 9, 2019
Priority date	Dec 7, 2018
Publication date	Mar 1, 2022
Grant date	Mar 1, 2022

Abstract

Systems, methods, techniques and apparatuses of power switches are disclosed. One embodiment is a power switch comprising a first reverse blocking integrated gate-commutated thyristor (RB-IGCT); a second RB-IGCT coupled in an antiparallel configuration with the first RB-IGCT; a transient voltage suppressor coupled in parallel with the first RB-IGCT and the second RB-IGCT; and a controller. The controller is structured to determine a direction of a current flowing through the power switch, determine a magnitude of the current flowing through the power switch exceeds a threshold, and turn off the one of the first RB-IGCT and the second RB-IGCT receiving a current flowing in a reverse direction in response to determining the magnitude of the current flowing through the power switch exceeds the threshold.

First claim

What is claimed is:

1. A power switch comprising:
a first reverse blocking integrated gate-commutated thyristor (RB-IGCT);
a second RB-IGCT coupled in an antiparallel configuration with the first RB-IGCT;
a transient voltage suppressor coupled in parallel with the first RB-IGCT and the second RB-IGCT; and
a controller structured to determine a direction of a current flowing through the power switch, determine one of the first RB-IGCT or the second RB-IGCT is receiving the current flowing in a forward direction, turn on the other of the first RB-IGCT or the second RB-IGCT such that both the first RB-IGCT and the second RB-IGCT is turned on in response to determining the current flowing through the first RB-IGCT is less than a polarity change threshold and decreasing, and wherein the first and second RB-IGCTs are turned on before the controller determines a magnitude of the current flowing through the power switch exceeds the threshold, and when the controller determines the magnitude of the current flowing through the power switch exceeds a threshold, turn off the one of the first RB-IGCT or the second RB-IGCT receiving the current flowing in a reverse direction in response to determining the magnitude of the current flowing through the power switch exceeds the threshold.

2. The power switch of claim 1 , wherein the controller is structured to turn off the one of the first RB-IGCT or the second RB-IGCT after a delay of a time period required for the other RB-IGCT to deplete a stored charge for load switching.

3. The power switch of claim 1 , wherein determining the direction of the current flowing through the power switch includes cyclically turning on the first RB-IGCT, measuring the magnitude of the current flowing through the first RB-IGCT, turning off the first RB-IGCT, turning on the second RB-IGCT, measuring the magnitude of the current flowing through the second RB-IGCT, and turning off the second RB-IGCT until the measured magnitude of the current flowing through the first RB-IGCT or second RB-IGCT exceeds the threshold.

4. The power switch of claim 1 , wherein determining the direction of the current flowing through the power switch includes measuring a differential voltage using a voltage sensor coupled to a first terminal of the power switch and a voltage sensor coupled to a second terminal of the power switch.

5. The power switch of claim 4 , wherein the controller is structured operate the first and second RB-IGCTs such that both the first RB-IGCT and the second RB-IGCT are turned on in response to determining the current flowing through the first RB-IGCT is less than a polarity change threshold and decreasing, the first RB-IGCT and the second RB-IGCT being turned on before the controller determines the magnitude of the current flowing through the power switch exceeds the threshold.

6. The power switch of claim 4 , wherein the controller is structured to measure the differential voltage at a zero current crossing.

7. The power switch of claim 1 , wherein the controller is structured to turn off the first RB-IGCT and the second RB-IGCT in response to determining a short circuit condition is occurring, wherein the controller determines short circuit condition is occurring includes comparing a change in the current over time to a short circuit threshold.

8. The power switch of claim 1 , wherein the power switch includes a solid state circuit breaker structured to interrupt a flow of medium voltage direct current or low voltage direct current.

9. A method comprising:
operating a power switch including a first reverse blocking integrated gate-commutated thyristor (RB-IGCT), a second RB-IGCT coupled in an antiparallel configuration with the first RB-IGCT, a transient voltage suppressor coupled in parallel with the first RB-IGCT and the second RB-IGCT; and a controller;
determining, with the controller, a direction of a current flowing through the power switch;
determining, with the controller, one of the first RB-IGCT or the second RB-IGCT is receiving the current flowing in a forward direction;
turning on the other of the first RB-IGCT or the second RB-IGCT such that both the first RB-IGCT and the second RB-IGCT is turned on in response to determining the current flowing through the first RB-IGCT is less than a polarity change threshold and decreasing, and wherein the first and second RB-IGCTs are turned on before the controller determines a magnitude of the current flowing through the power switch exceeds the threshold;
determining the magnitude of the current flowing through the power switch exceeds a threshold; and
turning off the one of the first RB-IGCT or the second RB-IGCT receiving a current flowing in a reverse direction in response to determining the magnitude of the current flowing through the power switch exceeds the threshold.

10. The method of claim 9 , comprising turning off one of the first RB-IGCT and the second RB-IGCT after a delay of a time period required for the other RB-IGCT to deplete a stored charge for load switching.

11. The method of claim 9 , wherein determining the direction of the current flowing through the power switch includes cyclically turning on the first RB-IGCT, measuring the magnitude of the current flowing through the first RB-IGCT, turning off the first RB-IGCT, turning on the second RB-IGCT, measuring the magnitude of the current flowing through the second RB-IGCT, and turning off the second RB-IGCT until the measured magnitude of the current flowing through the first RB-IGCT or second RB-IGCT exceeds the second threshold.

12. The method of claim 9 , wherein determining the direction of the current flowing through the power switch includes measuring a differential voltage using a voltage sensor coupled to a first terminal of the power switch and a voltage sensor coupled to a second terminal of the power switch.

13. The method of claim 12 , operating the first and second RB-IGCTs such that both the first RB-IGCT and the second RB-IGCT are turned on in response to determining the current flowing through the first RB-IGCT is less than a polarity change threshold and decreasing, the first RB-IGCT and the second RB-IGCT being both turned on before determining the magnitude of the current flowing through the power switch exceeds the threshold.

14. The method of claim 12 , wherein measuring the differential voltage occurs during a zero current crossing.

15. The method of claim 9 , comprising turning off the first RB-IGCT and the second RB-IGCT in response to determining a short circuit condition is occurring, and wherein determining the short circuit condition is occurring includes comparing a change in the current over time to a short circuit threshold.

16. The method of claim 9 , wherein the power switch includes a solid state circuit breaker structured to interrupt a flow of medium voltage direct current or low voltage direct current.

Assignees

• Abb Schweiz Ag

Inventors

• Cairoli Pietro
• Leoni Davide
• Raciti Luca

Classifications

• H02H1/0007

  concerning the detecting means (in general G01R or other subclasses of G01; reed switches H01H71/2445) · CPC title

• H02H3/093

  with timing means {(in general H02H3/027; thermal delay H02H3/085; timing means for undervoltage protection H02H3/247)} · CPC title

• H02H3/10 Primary

  additionally responsive to some other abnormal electrical conditions · CPC title

• H02H3/05 Primary

  with means for increasing reliability, e.g. redundancy arrangements {(for logic circuits H03K19/003)} · CPC title