Selective circuit breaker

• US 10,483,750 B2
• Filed: 06/18/2015
• Issued: 11/19/2019
• Est. Priority Date: 06/24/2014
• Status: Active Grant

• Current Assignee: Eaton Intelligent Power Limited (Eaton Corporation PLC.)
• Original Assignee: Eaton Intelligent Power Limited (Eaton Corporation PLC.)
• Inventors: Niehoff, Ronaldus
• Primary Examiner(s): Nguyen, Danny
• Application Number:
  US15/320,755
• Publication Number:
  US 20170163023A1
• Time in Patent Office: 1,615 Days
• Field of Search: 361 2- 13, 361 62- 69
• CPC Class Codes: H02H 3/006 Calibration or setting of parameters
• CPC Class Codes: H02H 3/027 with automatic disconnection after a predetermined time H02H3/033, H02H3/06 take precedence ; timing in overcurrent protection circuits H02H3/093; in undervoltage protection circuits H02H3/247; staggered disconnection H02H7/30
• CPC Class Codes: H02H 3/033 with several disconnections in a preferential order, e.g. following priority of the users, load repartitionH02H3/06 takes precedence
• CPC Class Codes: H02H 3/06 with automatic reconnection
• CPC Class Codes: H02H 3/08 responsive to excess current responsive to abnormal temperature caused by excess current H02H5/04
• CPC Class Codes: H02H 7/261 involving signal transmission between at least two stations transmission of signals in general H02H1/0061
• CPC Class Codes: H02H 7/30 Staggered disconnection

Abstract

A selective circuit breaker, in operation connectable between a main supply line and a downstream circuit breaker, has a bypass switch in a supply line, and a controlled semiconductor switch connected in parallel to the bypass switch. A bypass switch off detection circuitry and a short circuit detection circuitry are provided for controlling the bypass switch and the semiconductor switch in accordance with a switching characteristic. The switching characteristic of the selective circuit breaker is programmable, and a short circuit current rating of the selective circuit breaker is substantially equal to a short circuit current rating of the downstream circuit breaker.

Claims

1. A selective circuit breaker, in operation connectable between a main supply line and a downstream circuit breaker, the selective circuit breaker comprising:

a bypass switch in a supply line;

a controlled semiconductor switch connected in parallel to the bypass switch;

a bypass switch off detection circuitry; and

a short circuit detection circuitry configured to control the bypass switch and the controlled semiconductor switch in accordance with a switching characteristic,

wherein the switching characteristic is programmable,

wherein a short circuit current rating of the selective circuit breaker is substantially equal to a short circuit current rating of a downstream circuit breaker,

wherein the selective circuit breaker is operable in a normal operating mode or in a system limit selectivity mode,

wherein in the normal operating mode the selective circuit breaker is programmed to disconnect later than the downstream circuit breaker, and

wherein in the system limit selectivity mode the selective circuit breaker is programmed to apply a reconnect attempt.

2. The selective circuit breaker of claim 1, comprising the same components as the downstream circuit breaker.

3. The selective circuit breaker of claim 1, configured to select the normal selectivity or the system limit selectivity operating mode based on a dI/dt measurement in the main supply line.

4. The selective circuit breaker of claim 1, wherein in the system limit selectivity mode the selective circuit breaker is programmed to execute a reclosing attempt in a next zero-crossing of the mains supply after a switch off of the selective circuit breaker.

5. The selective circuit breaker of claim 1, wherein the switching characteristic is based on measurement of an energy parameter, measurement of current amplitude, and/or change of current over time (dI/dt).

6. The selective circuit breaker of claim 1, wherein the downstream circuit breaker is a conventional type circuit breaker.

7. The selective circuit breaker of claim 1, configured to change the switching characteristics depending on a mains supply source connected to the selective circuit breaker.

8. The selective circuit breaker of claim 1, configured to measure short circuit power on site during operation, and to change the switching characteristics accordingly.

9. The selective circuit breaker of claim 1, wherein the selective circuit breaker is configured to change a switch-off characteristic dependent on a detection of presence of persons.

10. The selective circuit breaker of claim 1, having a ground fault sensitivity substantially similar to a ground fault rating of the downstream circuit breaker, and a current threshold higher than a current threshold of the downstream circuit breaker.

11. The selective circuit breaker of claim 10, having a ground fault time delay which is longer than a ground fault time delay of the downstream circuit breaker.

12. The selective circuit breaker of claim 1, configured to detect whether a short circuit fault and/or a ground fault is present in wiring between the selective circuit breaker and the downstream circuit breaker.

13. The selective circuit breaker of claim 1, further comprising:

a communication interface configured to exchange data with the downstream circuit breaker.

14. A method for controlling a circuit breaker system, the method comprising:

connecting, between a downstream circuit breaker and a main supply line, a selective circuit breaker comprising a bypass switch in a supply line, and a controlled semiconductor switch connected in parallel to the bypass switch;

providing a bypass switch off detection circuitry for detecting the status of the bypass switch and a short circuit detection circuitry for detecting a short circuit situation or an overcurrent situation;

providing a processing unit for controlling the bypass switch and the semiconductor switch in accordance with a switching characteristic,

selecting, with a processing unit;

a normal operating mode, in which the selective circuit breaker is programmed to disconnect later than the downstream circuit breaker;

or

a system limit selectivity mode, in which the selective circuit breaker is programmed to apply a reconnect attempt, and

based on a dI/dt measurement in the main supply line.

15. The method according to claim 14, wherein the selective circuit breaker is connected to a plurality of downstream circuit breakers.

16. A selective circuit breaker, in operation connectable between a main supply line and a downstream circuit breaker, the selective circuit breaker comprising:

a bypass switch in a supply line;

a controlled semiconductor switch connected in parallel to the bypass switch;

a bypass switch off detection circuitry; and

a short circuit detection circuitry configured to control the bypass switch and the controlled semiconductor switch in accordance with a switching characteristic,

wherein the switching characteristic is programmable,

wherein a short circuit current rating of the selective circuit breaker is substantially equal to a short circuit current rating of a downstream circuit breaker, and

wherein the selective circuit breaker has a ground fault sensitivity substantially similar to a ground fault rating of the downstream circuit breaker, and a current threshold higher than a current threshold of the downstream circuit breaker.

17. The selective circuit breaker of claim 16, having a ground fault time delay which is longer than a ground fault time delay of the downstream circuit breaker.