Current transformer and direct current source based on current transformer

Patent metadata

Field	Value
Publication number	US-10276301-B2
Application number	US-201715708186-A
Country	US
Kind code	B2
Filing date	Sep 19, 2017
Priority date	Sep 27, 2016
Publication date	Apr 30, 2019
Grant date	Apr 30, 2019

Abstract

A current transformer and a direct current source based on a current transformer are disclosed. In an embodiment, the current transformer includes two output ends; a first winding and a second winding connected in series between the two output ends; a main core; a bypass core, arranged to be magnetically coupled with the main core. The first winding is wound on a part of the main core and a part of the bypass core, and the second winding is wound on apart of the bypass core. In an embodiment, the current transformer also includes a high-frequency bypass, connected in parallel with the first winding, and used to filter a high-frequency signal. The high-frequency bypass provides a low-impedance path for a high-frequency signal in a primary conductor under measurement, such that the bypass core with the second winding presents less obstruction to the main core, thereby reducing heating.

First claim

What is claimed is:

1. A current transformer, comprising:
a direct current (DC) input and an alternating current (AC) output;
two transformer output ends;
a first winding and a second winding, connected in series between the two output transformer ends;
a main core, including a closed magnetic loop;
a bypass core, arranged to be magnetically coupled with the main core, the first winding being wound on a part of the main core and a part of the bypass core, and the second winding being wound on a part of the bypass core; and
a high-frequency bypass, connected in parallel with the first winding, to filter a high-frequency signal.

2. The current transformer of claim 1 , wherein the high-frequency bypass is a high-pass filter circuit.

3. The current transformer of claim 2 , wherein the high-pass filter circuit includes a high-pass capacitor.

4. The current transformer of claim 3 , wherein at least one short circuit winding is wound on the bypass core, wherein the at least one short circuit winding is connected in a short-circuited manner.

5. A direct current source based on a current transformer, comprising:
a rectifying unit; and
the current transformer of claim 3 , wherein the rectifying unit is connectable to the two transformer output ends of the current transformer.

6. The current transformer of claim 2 , wherein at least one short circuit winding is wound on the bypass core, wherein the at least one short circuit winding is connected in a short-circuited manner.

7. A direct current source based on a current transformer, comprising:
a rectifying unit; and
the current transformer of claim 2 , wherein the rectifying unit is connectable to the two transformer output ends of the current transformer.

8. The current transformer of claim 1 , wherein the high-frequency bypass is a resonant circuit.

9. The current transformer of claim 8 , wherein the resonant circuit is a series-connected resonant circuit.

10. The current transformer of claim 9 , wherein the series-connected resonant circuit includes a series-connected resonant capacitor and a resonant winding, wherein the resonant winding is wound on a part of the bypass core.

11. The current transformer of claim 9 , wherein at least one short circuit winding is wound on the bypass core, wherein the at least one short circuit winding is connected in a short-circuited manner.

12. A direct current source based on a current transformer, comprising:
a rectifying unit; and
the current transformer of claim 9 , wherein the rectifying unit is connectable to the two transformer output ends of the current transformer.

13. The current transformer of claim 8 , wherein the resonant circuit is a parallel-connected resonant circuit.

14. The current transformer of claim 13 , wherein the parallel-connected resonant circuit includes a parallel-connected resonant capacitor and a resonant winding, and wherein the resonant winding is wound on a part of the bypass core.

15. The current transformer of claim 13 , wherein at least one short circuit winding is wound on the bypass core, wherein the at least one short circuit winding is connected in a short-circuited manner.

16. A direct current source based on a current transformer, comprising:
a rectifying unit; and
the current transformer of claim 13 , wherein the rectifying unit is connectable to the two transformer output ends of the current transformer.

17. The current transformer of claim 8 , wherein at least one short circuit winding is wound on the bypass core, wherein the at least one short circuit winding is connected in a short-circuited manner.

18. A direct current source based on a current transformer, comprising:
a rectifying unit; and
the current transformer of claim 8 , wherein the rectifying unit is connectable to the two transformer output ends of the current transformer.

19. A direct current source based on a current transformer, comprising:
a rectifying unit; and
the current transformer of claim 1 , wherein the rectifying unit is connectable to the two transformer output ends of the current transformer.

Assignees

• Siemens Ag

Inventors

• Du Feng
• Chen wei gang
• Zhuo Yue

Classifications

• H03H7/09

  Filters comprising mutual inductance · CPC title

• H02M2001/0006

  Electricity · mapped topic

• H01F38/28 Primary

  Current transformers · CPC title

• H03H7/0115 Primary

  comprising only inductors and capacitors (H03H7/075, H03H7/09, H03H7/12, H03H7/13 take precedence) · CPC title

• H01F38/30 Primary

  Constructions · CPC title