Partial discharge transducer

Patent metadata

Field	Value
Publication number	US-11287463-B2
Application number	US-201816235747-A
Country	US
Kind code	B2
Filing date	Dec 28, 2018
Priority date	Dec 28, 2018
Publication date	Mar 29, 2022
Grant date	Mar 29, 2022

Abstract

A partial discharge (PD) transducer that includes a PD sensor configured to sense a PD event of an electrical system. At least one light emitting device (LED) is arranged in series with the PD sensor. The LED is configured to receive the electrical sensor signal from the PD sensor and to generate a light signal in response to the electrical sensor signal.

First claim

The invention claimed is:

1. A partial discharge transducer system, comprising:
a partial discharge (PD) sensor configured to sense a partial discharge event of an electrical system;
at least one light emitting device (LED) in series with the PD sensor, the LED configured to:
receive an electrical sensor signal from the PD sensor; and
generate a light signal in response to the electrical sensor signal; and

a PD detection processor operatively coupled to the PD sensor and configured to:
monitor for changes of one or both of usage and loading of the electrical system over time based on characteristics of the sensed PD events; and
predict a time of failure of the electrical system based on the monitored changes of one or both of the usage and the loading of the electrical system over time.

2. The partial discharge transducer system of claim 1 , wherein the PD sensor comprises a transient earth voltage sensor, or high-frequency coupling capacitor.

3. The partial discharge transducer system of claim 1 , further comprising a high pass filter connected between the PD sensor and the LED.

4. The partial discharge transducer system of claim 1 , further comprising a voltage regulator arranged in parallel with the LED, the voltage regulator configured to bring an effective turn-on voltage of the LED to about 0V.

5. The partial discharge transducer system of claim 1 , wherein a response time of the LED comprises:
a rise time greater than 5 ns; and
a fall time greater than 5 ns.

6. A partial discharge monitoring system, comprising:
multiple partial discharge (PD) transducers, each partial discharge transducer comprising:
a partial discharge (PD) sensor configured to sense a PD event of a monitored electrical system and to generate an electrical sensor signal in response to the PD event;
at least one light emitting device (LED) in series with the PD sensor, the LED configured to:
receive the electrical sensor signal from the PD sensor; and
generate an analog light signal in response to the electrical sensor signal;

at least one optical fiber optically coupled to receive light from the LED and configured to carry the analog light signal from a location proximate to the monitored electrical system to a location remote from the monitored electrical system;
at least one light receiving device at the remote location configured to generate an analog electrical signal in response to the analog light signal; and
a PD detection processor operatively coupled to the PD sensor and configured to:
monitor for changes of one or both of usage and loading of the electrical system over time based on characteristics of the sensed PD events; and
predict a time of failure of the electrical system based on the monitored changes of one or both of the usage and the loading of the electrical system over time.

7. The monitoring system of claim 6 , wherein:
the at least one LED device includes:
at least one first LED in series with the PD sensor, the first LED coupled to receive the electrical sensor signal from the PD sensor, the first LED configured to generate a first analog light signal in response to positive going pulses of the electrical sensor signal; and
at least one second LED in series in the PD sensor, the second LED coupled to receive the electrical sensor signal from the PD sensor, the second LED configured to generate a second analog light signal in response to negative going pulses of the electrical sensor signal;
the at least one optical fiber comprises:
at least one first optical fiber optically coupled to receive the first analog light signal from the first LED and configured to carry the first analog light signal from a location proximate to the monitored electrical system to a location remote from the monitored electrical system; and
at least one second optical fiber optically coupled to receive the second analog light signal from the second LED and configured to carry the second analog light signal from a location proximate to the monitored electrical system to a location remote from the monitored electrical system; and

the at least one light receiving device comprises:
at least one first light receiving device configured to generate a first analog electrical signal in response to the first analog light signal; and
at least one second light receiving device configured to generate a second analog electrical signal in response to the second analog light signal.

8. The monitoring system of claim 6 , wherein the PD detection processor is configured to analyze the analog electrical signal or a signal derived therefrom and to detect the PD event based on the analysis.

9. The monitoring system of claim 6 , wherein the PD detection processor is configured to compare at least one value of the electrical sensor signal or a signal derived therefrom to a threshold value and to detect the PD event based on the comparison.

10. The monitoring system of claim 6 , wherein the PD detection processor is configured to determine a magnitude of charge transfer of the PD event.

11. The monitoring system of claim 10 , wherein the PD detection processor is configured to apply a conversion algorithm to determine the magnitude of charge transfer of the PD event.

12. The monitoring system of claim 6 , wherein the PD detection processor is configured to:
compare a signature of the electrical sensor signal or a signal derived therefrom to a previously obtained signature of the electrical sensor signal or the signal derived therefrom; and
determine degradation of the electrical system based on the comparison.

13. The monitoring system of claim 6 , wherein the PD detection processor is configured to:
monitor for changes of a load pattern of the electrical system over time based on characteristics of PD events; and
predict the time of failure of the electrical system based on the monitored changes of the load pattern over time.

14. A partial discharge transducer system, comprising:
a partial discharge (PD) sensor configured to sense a PD event of an electrical system and to generate an electrical sensor signal in response to the PD event;
a first light emitting device (LED) coupled to receive the electrical sensor signal from the PD sensor, the first LED configured to generate a first light signal in response to positive going pulses of the electrical sensor signal;
a second LED in parallel with the first LED, the second LED coupled to receive the electrical sensor signal from the PD sensor, the second LED configured to generate a second light signal in response to negative going pulses of the electrical sensor signal; and
a PD detection processor operatively coupled to the PD sensor and configured to:
monitor for changes of one or both of usage and loading of the electrical system over time based on characteristics of the sensed PD events; and
predict a time of failure of the electrical system based on the monitored changes of one or both of the usage and the loading of the electrical system over time.

15. A partial discharge monitoring system, comprising:
multiple partial discharge transducers, each partial discharge transducer comprising:
a partial discharge (PD) sensor configured to sense a partial discharge event of an electrical system;
a first light emitting device (LED) coupled to receive an electrical sensor signal caused by the partial discharge event from the PD sensor, the first LED arranged such that the first LED generates a first analog light signal in response to positive going pulses of the electrical sensor signal; and
a second LED arranged in parallel with the first LED, the second LED co

Assignees

• Palo Alto Res Ct Inc

Inventors

• Karin Todd
• Kiesel Peter
• Raghavan Ajay

Classifications

• G01R15/16

  using capacitive devices · CPC title

• G01R31/1218 Primary

  using optical methods; using charged particle, e.g. electron, beams or X-rays · CPC title

• G01R31/1272

  of cable, line or wire insulation, e.g. using partial discharge measurements (locating faults in cables G01R31/083) · CPC title

• G01R15/22

  using light-emitting devices, e.g. LED, optocouplers {(G01R31/31901 takes precedence)} · CPC title

• G01R31/1227

  of components, parts or materials (G01R31/1209, G01R31/1218, G01R31/18 take precedence; circuits therefor G01R31/14; testing vessels of electrodes G01R31/16) · CPC title