Converter transformer bushing external insulation design

Summary

The voltage at the converter transformer bushings in the DC side includes a DC component plus harmonics. Since it is not possible to design and test insulators with exactly the above stresses, equivalent voltage stress must be defined to verify the performance of the bushing external insulation under steady state conditions. Based on available experimental results, the paper proposes to perform tests with an AC equivalent voltage. Consequences for the design under pollution and icing conditions are discussed, making also reference to recent experimental results.

Additional informations

Authors

THRONICKER, BERTA, WATERS, HADDAD

Keywords

HVDC, converter transforrmers, bushings, equivalent voltage