Method and testing device for testing wiring of transformers

Patent metadata

Field	Value
Publication number	US-10859612-B2
Application number	US-201615579486-A
Country	US
Kind code	B2
Filing date	Jul 7, 2016
Priority date	Jul 7, 2015
Publication date	Dec 8, 2020
Grant date	Dec 8, 2020

Abstract

A testing device for an apparatus of an energy system which has inputs that can be connected in a conductive manner to at least one current transformer and at least one voltage transformer. The testing device is designed to apply a first test signal to a secondary side of the voltage transformer and, at the same time, to apply a second test signal to a primary side of the current transformer.

First claim

The invention claimed is:

1. A method for testing wiring of a current transformer and a voltage transformer of a device of an electrical energy system, comprising the steps
applying a first test signal generated by a first test signal source to a secondary side of the voltage transformer, and
impressing a second test signal generated by a second test signal source into a primary side of the current transformer,
wherein the first test signal and the second test signal are generated at the same time,
detecting a response of the device to the first test signal and the second test signal,
calculating an expected response depending on an amplitude of the first test signal, an amplitude of the second test signal and a phase angle between the first test signal and the second test signal, and
comparing the detected response with the expected response to detect an incorrect wiring of the current transformer and the voltage transformer.

2. The method as claimed in claim 1 ,
wherein the response of the device comprises an arithmetic sign or an absolute value of a power recorded by the device.

3. The method as claimed in claim 1 ,
wherein the first test signal is an AC voltage and wherein the second test signal is an AC current.

4. The method as claimed in claim 1 ,
wherein the first test signal and the second test signal are in phase.

5. The method as claimed in claim 1 ,
wherein the first test signal is applied to the secondary side of the voltage transformer that is associated with a first phase of multiple phases, and
wherein the second test signal is impressed into the primary side of the current transformer that is connected to the first phase.

6. The method as claimed in claim 5 , further comprising the step:
generating at least one further test signal to test the wiring of at least one further transformer that is connected to a further phase, which is different than the first phase, of a multi-phase line.

7. The method as claimed in claim 6 ,
wherein the at least one further test signal is generated at the same time as the first test signal and the second test signal.

8. The method as claimed in claim 1 ,
wherein the first test signal and at least one further AC voltage signal are applied to the secondary side of at least two voltage transformers of the device that are associated with different phases at the same time.

9. The method as claimed in claim 8 ,
wherein the first test signal and the at least one further AC voltage signal have different amplitudes.

10. The method as claimed in claim 1 ,
wherein the second test signal and at least one further AC current signal are applied to the primary side of at least two current transformers of the device that are associated with different phases at the same time.

11. The method as claimed in claim 10 ,
wherein the second test signal and the at least one further AC current signal have different amplitudes.

12. The method as claimed in claim 1 ,
wherein the voltage transformer is disconnected on the secondary side for the testing of the wiring of the current transformer and the voltage transformer.

13. The method as claimed in claim 1 ,
wherein the device comprises a protective relay.

14. A testing apparatus for testing wiring of a current transformer and a voltage transformer of a device of an electrical energy system, comprising
a first terminal for applying a first test signal generated by a first test signal source to a secondary side of the voltage transformer,
a second terminal for impressing a second test signal generated by a second test signal source into a primary side of the current transformer,
wherein the testing apparatus is set up to generate the first test signal applied to the secondary side of the voltage transformer and the second test signal impressed into the primary side of the current transformer at the same time, and
an electronic computation device that is set up to computationally ascertain an expected response of the device to the first test signal and the second test signal from an amplitude of the first test signal, an amplitude of the second test signal and a phase relationship between the first test signal and the second test signal,
wherein the testing apparatus is configured to detect a response of the device of the electrical energy system to the first test signal and the second test signal and to compare the detected response with the expected response to detect an incorrect wiring of the current transformer and the voltage transformer.

15. The testing apparatus as claimed in claim 14 , further comprising
an output interface for outputting the computationally ascertained expected response or an input interface for receiving the response of the device.

16. The testing apparatus as claimed in claim 14 , further comprising
a controllable voltage source as the first test signal source for generating the first test signal and a controllable current source as the second test signal source for generating the second test signal.

17. The testing apparatus as claimed in claim 14 ,
wherein the testing apparatus is set up to apply the first test signal and at least one further AC voltage signal to the secondary side of at least two voltage transformers of the device that are associated with different phases at the same time.

18. The testing apparatus as claimed in claim 17 ,
wherein the testing apparatus is set up to generate the first test signal and the at least one further AC voltage signal such that they have different amplitudes.

19. The testing apparatus as claimed in claim 14 ,
wherein the testing apparatus is set up to impress the second test signal and at least one further AC current signal into the primary side of at least two current transformers of the device that are associated with different phases at the same time.

20. The testing apparatus as claimed in claim 19 ,
wherein the testing apparatus is set up to generate the second test signal and the at least one further AC current signal such that they have different amplitudes.

21. The testing apparatus as claimed in claim 14 ,
wherein the testing apparatus is configured as a portable tester.

22. A system comprising
the testing apparatus as claimed in claim 14 , and
the device comprising the voltage transformer and the current transformer.

23. The system as claimed in claim 22 ,
wherein the device comprises a protective relay, a power display in a control room or a measuring device.

Assignees

• Omicron Electronics Gmbh

Inventors

• Klapper Ulrich
• Kaiser Steffen

Classifications

• G01R31/50

  Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections (testing of sparking plugs H01T13/58) · CPC title

• G01R31/72

  Testing of electric windings (testing of transformers G01R31/62) · CPC title

• G01R35/00 Primary

  Testing or calibrating of apparatus covered by the other groups of this subclass · CPC title

• G01R35/02

  of auxiliary devices, e.g. of instrument transformers according to prescribed transformation ratio, phase angle, or wattage rating · CPC title

• G01R1/28 Primary

  Provision in measuring instruments for reference values, e.g. standard voltage, standard waveform · CPC title