A new approach to partial discharge measurements for testing electrical insulation systems

Rights statement
Awarding institution
  • University of Strathclyde
Date of award
  • 2007
Thesis identifier
  • T11978
Qualification Level
Qualification Name
Department, School or Faculty
  • Partial discharge (PD) data has been recorded simultaneously using the conventional IEC60270 `apparent charge' measurement technique and the more recent Radio Frequency (RF) method. Due to the different responses of each system, combined measurement allows additional information on the nature of the PD source to be gained. PD was produced using a number of test cells containing PD sources typically encountered in practical insulation systems, such as free particles, floating electrodes and voids. When RF energy is plotted against apparent charge for a large number of discharges, characteristic patterns appear which may be used to distinguish between PD sources. Additionally, the combined technique has the ability to distinguish between simultaneously active PD sources by the appearance of multiple clusters. Additional work has been carried out to aid in the understanding and interpretation of these relationships. For example, an algorithm that models the complete response of a gas-insulated switchgear chamber has shown that PDs with a consistent pulse width produce correlation patterns that resemble a quadratic relationship. Additionally, direct PD current pulse measurement has shown a large variation in current pulse shape with faster rise times than previously expected (35 ps minimum). It is envisioned that the ability to relate RF measurements to the internationally accepted apparent charge level will aid in the general acceptance of the RF technique as a tool to quantify PD severity.
Resource Type
Date Created
  • 2007
Former identifier
  • 771232