Power device including current transformer and method for compensating of current transformer

Patent metadata

Field	Value
Publication number	US-9612275-B2
Application number	US-201414524482-A
Country	US
Kind code	B2
Filing date	Oct 27, 2014
Priority date	Dec 5, 2013
Publication date	Apr 4, 2017
Grant date	Apr 4, 2017

Abstract

A power device having a current transformer according to an embodiment includes: first to Nth current transformers; an integrated measurement panel connected to the first to Nth transformers and configured to measure actual current values of locations where the first to Nth transformers are installed using current values detected by the first to Nth transformers, wherein the integrated measurement panel stores compensation values for compensating errors of linearity characteristics of the first to Nth current transformers, and measures the actual current values by applying the stored compensation values.

First claim

What is claimed is:

1. A power device having a current transformer, the power device comprising:
first to Nth current transformers;
an integrated measurement panel connected to the first to Nth transformers and comprising a memory configured to store compensation values for compensating abnormal linearity characteristics for each current interval of one or more current transformers of the first to Nth current transformers,
wherein the integrated measurement panel is configured to:
measure current values of locations where the first to Nth transformers are installed using current values detected by the first to Nth transformers;
determine if compensation of each of the measured current values of the first to Nth current transformers is necessary; and
compensate one or more of the measured current values using the compensation values stored in the memory when compensation is necessary for the one or more of the measured current values.

2. The power device according to claim 1 , wherein the integrated measurement panel is further configured to determine that compensation of a measured current value is necessary when a linearity characteristic of a current transformer corresponding to the measured current falls outside of a normal range based on an average value of the linearity characteristics of the first to Nth current transformers.

3. The power device according to claim 2 , wherein the integrated measurement panel is further configured to determine the compensation values differently for each interval to which the current values measured by the first to Nth current transformers belong.

4. The power device according to claim 3 , wherein the compensation values include conditions for compensating the measured current values.

5. The power device according to claim 4 , wherein the compensation conditions comprise at least one of a current change ratio, an offset value; or a gain value.

6. A compensation method for a current transformer, comprising:
measuring current values of locations where a plurality of current transformers are installed using current values detected by first to Nth transformers of the plurality of current transformer;
determining if compensation of each of the measured current values of the first to Nth current transformers is necessary based on a linearity characteristic of each current transformer; and
compensating one or more of the measured current values using the compensation values stored in a memory when compensation is necessary for the one or more measured current values.

7. The compensation method according to claim 6 , further comprising determining that compensation of a measured current value is necessary when a linearity characteristic of a current transformer corresponding to the measured current falls outside of a normal range based on an average value of the linearity characteristic of the first to Nth current transformers.

8. The compensation method according to claim 7 , further comprising determining the compensation value differently for each interval to which the current values measured by the first to Nth current transformers belong.

9. The compensation method according to claim 7 , wherein the compensation values include conditions for compensating the measured current values.

10. The compensation method according to claim 9 , wherein the compensation conditions comprise at least one of a current change ratio, an offset value; or a gain value.

Assignees

• Lsis Co Ltd

Inventors

• Choi Yong Kil
• Choi Ho Seok

Classifications

• G01R21/00 Primary

  Arrangements for measuring electric power or power factor (G01R7/12 takes precedence) · CPC title

• G01R31/2837 Primary

  Characterising or performance testing, e.g. of frequency response (transient response G01R27/28) · CPC title

• H01F27/42 Primary

  Circuits specially adapted for the purpose of modifying, or compensating for, electric characteristics of transformers, reactors, or choke coils (circuits for controlling transformers, reactors or choke coils, for the purpose of obtaining a desired output H02P13/00; impedance networks H03H) · CPC title

• G01R31/2843

  In-circuit-testing · CPC title

• H02P13/00

  Arrangements for controlling transformers, reactors or choke coils, for the purpose of obtaining a desired output · CPC title