Fault current limiter

Patent metadata

Field	Value
Publication number	US-9490628-B2
Application number	US-201414528949-A
Country	US
Kind code	B2
Filing date	Oct 30, 2014
Priority date	Nov 15, 2013
Publication date	Nov 8, 2016
Grant date	Nov 8, 2016

Abstract

A fault current limiter is provided. According to an embodiment of the present disclosure, the fault current limiter includes a switch whose contact point is opened when a fault current occurs; a current limiting element configured to limit the fault current when the fault current occurs; and a diode being serial-connected to the current limiting element, wherein a breakdown voltage of the diode is higher than a voltage drop by an impedance of the switch when a normal current flows.

First claim

What is claimed is:

1. A fault current limiter, the limiter comprising:
a measuring unit configured to measure a current;
a detecting unit configured to transmit an opening signal for opening a switch and a turn-off signal for turning off a power semiconductor when a fault current is determined to occur by the measuring unit;
the switch configured to open the contact point by the opening signal;
the power semiconductor serial-connected to the switch to form a main path and configured to be turned off by the turn-off signal;
a current limiting element configured to limit the fault current;
a diode serial-connected to the current limiting element to form a limiting path and configured to block a normal current into the limiting path; and
a second resistor unit disposed between the diode and the current limiting element and configured to limit a first peak current of the fault current.

2. The limiter of claim 1 , wherein the diode includes:
a first diode in forward direction; and
a second diode parallel-connected to first diode in reverse direction.

3. The limiter of claim 1 , wherein a breakdown voltage of the diode is higher than a voltage drop by an impedance of the main path when the normal current flows.

4. The limiter of claim 1 , wherein a breakdown voltage of the diode is higher than a voltage drop by an impedance of the power semiconductor and the switch when the normal current flows.

5. The limiter of claim 1 , wherein the current limiting element includes:
a first power fuse configured to block the fault current into the limiting path;
a first resistor unit parallel-connected to the first power fuse and configured to block the fault current after the first power fuse is fused; and
a second power fuse serial-connected to the first resistor unit and configured to block the fault current after passing through the first resistor unit.

6. The limiter of claim 1 , wherein a connection between the diode and the second resistor unit is parallel-connected to the power semiconductor and the current limiting element is parallel-connected to the switch.

7. The limiter of claim 1 , wherein a voltage drop by resistance of the second resistor unit is smaller than that of the power semiconductor.

8. The limiter of claim 1 , wherein the detection unit is further configured to transmit the opening signal before the turn-off signal.

Assignees

• Lsis Co Ltd

Inventors

• Sim Jung Wook
• Lee Gyeong Ho
• Park Hae Yong

Classifications

• H01H33/02

  Details · CPC title

• H02H9/026

  Current limitation using PTC resistors, i.e. resistors with a large positive temperature coefficient · CPC title

• H02H3/08

  responsive to excess current (responsive to abnormal temperature caused by excess current H02H5/04) · CPC title

• H02H3/025

  Disconnection after limiting, e.g. when limiting is not sufficient or for facilitating disconnection · CPC title

• H01H9/54 Primary

  Circuit arrangements not adapted to a particular application of the switching device and for which no provision exists elsewhere · CPC title