Method of diagnosing partial discharge in gas-insulated apparatus and partial discharge diagnosing system for carrying out the same

• US 6,300,768 B1
• Filed: 01/24/2000
• Issued: 10/09/2001
• Est. Priority Date: 01/28/1999
• Status: Expired due to Term

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Kato, Tatsuro, Endo, Fumihiro
• Primary Examiner(s): Brown, Glenn W.
• Assistant Examiner(s): Hamdan, Wasseem H.
• Application Number:
  US09/490,279
• Time in Patent Office: 624 Days
• Field of Search: 324/600, 324/551, 324/536, 324/424, 324/535, 324/537, 324/122, 340/644, 702/38, 361/113
• US Class Current: 324/536
• CPC Class Codes: G01R 31/1254 of gas-insulated power appliances or vacuum gaps testing switches G01R31/327; detecting electrical or mechanical defects in encased switchgear H02B13/065
• CPC Class Codes: H02H 1/0015 Using arc detectors
• CPC Class Codes: H02H 1/0092 concerning the data processing means, e.g. expert systems, neural networks

Abstract

The present invention provides a method of diagnosing a partial discharge in a gas-insulated apparatus and a partial discharge diagnosing system for carrying out the same to achieve highly accurate diagnosis through the detection of a partial discharge signal and diagnosing the partial discharge signal through multiple conditional branching. The partial discharge diagnosing system of the present invention comprises: a partial discharge signal detector for detecting a partial discharge signal representing a partial discharge produced in the gas-insulated apparatus, a signal analyzer for receiving the partial discharge signal detected by the partial discharge detector and analyzing the partial discharge signal, a diagnostic unit for determining a cause of the partial discharge on the basis of results of analysis made by the signal analyzer, and a display unit for displaying results of diagnosis. The diagnostic unit is provided with a diagnostic means to make multiple conditional branching to a plurality of second diagnostic means according to result of diagnosis made by a first diagnostic means, and obtains a result of diagnosis made by the second diagnostic means, thereby achieving highly accurate diagnosis by detecting the partial discharge signal and subjecting the partial discharge signal to multiple conditional branching.

Claims

1. The partial discharge diagnosing system for diagnosing a partial discharge produced in a gas-insulated apparatus, said partial discharge diagnosing system comprising:

a partial discharge signal detector for detecting a partial discharge signal representing a partial discharge produced by the gas-insulated apparatus;

a signal analyzer for receiving the partial discharge signal detected by the partial discharge signal detector and analyzing the partial discharge signal;

a diagnostic unit for determining a cause of said partial discharge on the basis of results of analysis made by said signal analyzer, provided with a diagnostic means for multiple conditional branching; and

a display unit for displaying said results of diagnosis;

wherein said diagnostic means of said diagnostic unit makes conditional branching to one of a plurality of second diagnostic means according to result of diagnosis made by a first diagnostic means, and obtains a result of diagnosis made by the second diagnostic means;

wherein said diagnostic unit employs a neural network; and

wherein said neural network receives results of analysis made by said signal analyzer and carries out rediagnosis when an output of the neural network is 0.5 or less.