Partial discharge source classification using pattern recognition algorithms

Design, development, and testing of a comprehensive and automated classification system for single and multiple partial discharge (PD) source identification based on the relationship between the variation of phase resolved partial discharge (PRPD) patterns and the sources of PD is proposed. The proposed system consists of feature extraction methods and classifier algorithms that are implemented for recognition of partial discharge patterns. Once the PRPD patterns are recorded, features generation algorithms are applied on the collected data. For single PD source identification, twelve high performance, applicable feature extraction techniques on PRPD patterns are employed to extract features. In order to present a comprehensive classification system, 10 well-known algorithms for the classification of PD sources have then been used. To evaluate the performance of the classification system, three laboratory test setups are designed and built to simulate various types of PD activities. The first test setup includes test cells which are designed to model common sources of PD in air, oil, and SF6. Using this setup, the application of automated classification system on different sources of PD in different HV insulation media is investigated. The second and third test setups are designed to test the classification system on identification of different sources of PD in oil-immersed insulation and power transformer cellulose insulation under both electrical and thermal stresses, respectively. In many practical situations, the interest lies in the identification of multiple, simultaneously activated PD sources in insulation. Multi-source PDs sometimes results in partially overlapped patterns, which makes them hard to be identified by single source identification techniques. To further enhance the proposed classification system, a novel algorithm to identify Multi-source PDs is developed and appended to the system. To evaluate the performance of this