Fault Identification of Dry-type Potential Transformer Combining Improved Genetic Algorithm and Frequency Domain Spectroscopy

In recent years, insulation faults of dry-type potential transformer (PT) occur frequently, which seriously affects the safe and reliable operation of power system. Since insulation failure is one of the main factors causing dry-type PT retirement, it is very significant to perform the insulation condition diagnosis and identification of dry-type PT, which can lay a foundation for reliable operation and maintenance of dry-type PT. In this paper, the frequency dielectric principle of dry-type PT are analyzed deeply. Then the frequency dielectric response measurement system is established to test the frequency dielectric properties of dry-type PT with good insulation and degraded insulation from 10–
³
Hz to 10
³
Hz. Moreover, combined with the improved genetic algorithm, the RC circuit parameters of dry-type PT with good insulation and degraded insulation are identified and analyzed. Finally, based on the RC circuit parameters, the evolution mechanism of frequency dielectric properties of dry-type PT with good insulation and degraded insulation is discussed. This paper can provide technical support and reference for fault diagnosis of dry-type PT and other power equipment.