Corona discharge detection system for detecting the presence of any corona discharge in an electrical system

• US 4,006,410 A
• Filed: 12/19/1975
• Issued: 02/01/1977
• Est. Priority Date: 12/19/1975
• Status: Expired due to Term

• Current Assignee: Lee A. Chagra
• Original Assignee: Lee A. Chagra
• Inventors: Roberts, Danvern R.
• Primary Examiner(s): Strecker, Gerard R.
• Application Number:
  US05/642,550
• Time in Patent Office: 410 Days
• Field of Search: 324/52, 324/54, 324/72, 324/103, 324/113, 360/6
• US Class Current: 324/520
• CPC Class Codes: G01R 13/16 Recording on a magnetic medium
• CPC Class Codes: G01R 31/086 in power transmission or distribution networks, i.e. with interconnected conductors
• CPC Class Codes: G01R 31/12 Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing G01R31/08, G01R31/327 and G01R31/72 take precedence; measuring in plasmas G01R19/0061; measuring dielectric constants G01R27/2617; ESD, EMC or EMP testing of circuits G01R31/002

Abstract

A corona discharge detection system is disclosed. The detection system is composed of two basic sub-systems, a detection record system and a detection playback. The detection record system detects a corona discharge, visually displays the discharge on a cathode ray tube and records the corona discharge video data along with voice and geographic data. The playback system processes the recorded information to provide a playback of the recorded data. The playback system includes an audio system that reproduces the stored audio information and a strip chart recorder that reproduces the corona video data and the geographic data to provide a visual record of this data.

Claims

1. A corona discharge detection system comprising:

detection means for detecting corona discharges in an electrical system;

selection means coupled to said detection means for selecting only specified frequency components of any detected corona discharges;

processing means coupled to said selection means for processing said selected frequency components to produce video corona discharge data for each detected corona discharge;

recording means having a first track and a second track.

recorder and corona alarm detection condition amplifier means coupled to the output of said processing means;

corona alarm means coupled to said recorder and corona alarm condition amplifier means for producing an alarm indication in response to any video corona discharge data from said recorder and corona alarm condition amplifier means;

a video record amplifier processor for amplifying and processing any video corona discharge data from said recorder and corona alarm condition amplifier means;

means coupled to the output of said video record amplifier processor for recording any video corona discharge data output from said video record amplifier processor on said first track of said recording means;

audio record amplifier means having a first input, a second input and an output;

means to apply voice frequency logging information signals to said first input of said audio record amplifier means;

a marker time base generator coupled to said second input of said audio record amplifier means, said marker time base generator providing geographic data signals indicative of the geographic location of any detected corona discharges; and

means coupled to said output of said audio record amplifier means to record said voice frequency logging information signals and said geographic data signals from said marker and time base generator on said second track of said recording means.

2. A corona discharge detection system as defined in claim 1 wherein said selected frequency components of said detected corona discharges are the high frequency components and wherein said selection means for selecting only said specified frequency components includes a corona window selector.

3. A corona discharge detection system as defined in claim 2 wherein said recording means is a magnetic tape recorder having a video record head, an audio record head and a magnetic tape having said first track and said second track.

4. A corona discharge detector system as defined in claim 3 wherein said means for recording said video corona discharge data on said first track includes said video record head and said means for recording said voice logging information and said geographic data on said second track includes said audio record head.

5. A corona discharge system as defined in claim 4 wherein said voice logging information input means comprises a microphone, and a preamplifier having its input coupled to said microphone and its output coupled to said audio record.

6. A corona discharge detection system as defined in claim 5 wherein a cathode ray tube display is coupled to said processing means.

7. A corona discharge detection system as defined in claim 6 further including playback means for playing back said corona discharge data recorded on said first track and said voice logging information and said geographic data recorded on said second track.

8. A corona detection system as defined in claim 6 wherein said playback means comprises:

a video playback head for detecting said video corona discharge data recorded on said first track;

a video condition amplifier coupled to the output of video playback head;

a strip chart video detector amplifier coupled to the output of said video condition amplifier;

a strip chart recorder having a first pen input and a second pen input;

means to couple the output of said strip chart video detector amplifier to said first pen input of said strip chart recorder;

an audio playback head;

an audio condition amplifier having an input coupled to said audio playback head and having a first output and a second output;

an audio amplifier coupled to said first output of said audio condition amplifier;

a speaker coupled to said audio amplifier;

a mark discriminator coupled to said second output of said audio condition amplifier;

wave trap filter means for filtering out all but said geographic data signals from the output of said mark discriminator;

a marker amplifier relay driver coupled to the output of said mark discriminator to receive said geographic data signals from said mark discriminator; and

means to couple the output of said marker amplifier relay driver to said record pen input of said strip chart recorder.

9. A corona discharge detector system as defined in claim 8 wherein said detection means for detecting corona discharges in an electrical system comprises a discone antenna.

10. A corona discharge detection system as defined in claim 8 wherein said detection means for detecting corona discharges in an electrical system comprises a probe.