Radio and audible noise performance of T2 conductors

The Central Iowa Power Cooperative (CIPCO) plans to build a 345 kV overhead power line using a bundle of four Partridge T2 conductors. The T2 conductor is two normal cylindrical conductors twisted together to prevent galloping during freezing rain and wind. Since it was not known whether any of the analytical expressions for calculating the radio and audible noise performance of conductors would work for T2 conductors, measurements were performed in the Bonneville Power Administration's (BPA) high voltage laboratory to compare the radio influence voltage (RIV) and audible noise (AN) performance of the Partridge T2, Partridge and Dove conductors. The Dove conductor has about the same cross-section and current-carrying capacity as the Partridge T2 conductor. The tests showed that no consistent, measurable difference could be found in the RIV and AN levels between the Partridge T2 and Dove conductors under dry or artificial rain conditions and whether the conductors were arranged in bundles of 4, 3, or 2 subconductors or as single conductors.