EFFECT OF BUNDLE ORIENTATION ON TRANSMISSION-LINE AUDIBLE AND RADIO NOISE

A bundle of four conductors may be used for the next generation of 500 -kV fines at the Bonneville Power Administration (BPA). Among the many questions that needed answers were (a) the optimal orientation of the bundle to minimize the audible (AN) and radio noise (RI) and (b) whet her trapezoidal conductors behaved differently than conventional stran ded conductors. This paper shows the results of comparative tests cond ucted in BPA's high voltage laboratory comparing the RI and AN from 4 Bunting (conventional round rod) and 4 Hood (trapezoidal) conductors o riented either in a square or a diamond configuration. To make the res ults more useful, similar tests were conducted on 2 Bunting and 2 Hood conductors oriented either horizontally or vertically and on 3 Buntin g and 3 Hood conductors oriented in a vee or an inverted vee configura tion. Tests on single Bunting and Hood conductors were also conducted. The tests showed that within the accuracy of noise measurements bundl e orientation has little effect on the AN or RI and that the conventio nal Bunting and the trapezoidal Hood conductors have essentially the s ame noise performance.