Project EHV-preliminary corona investigations: the effect of harmonics on corona losses

PROJECT EHV is a prototype 3-phase transmission line intended to be operated at voltages as high as 750 kv to permit a study of the factors affecting the design and operation of extra-high-voltage (EHV) transmission lines. It is being constructed near Pittsfield, Mass., USA, and will be approximately 4.3 miles long. Since it is a developmental line, it is to be equipped with an unusually wide range of instruments for the measurement of environmental conditions and many mechanical and electrical quantities. Among the latter is complete instrumentation for the measurement of corona losses. Information on corona losses will be correlated statistically with other information such as meteorological conditions and radio noise. This paper describes some of the preliminary work done to assist in the choice of suitable instrumentation for the measurement of corona losses.