Measurement of Impulsive Noise on Electric Distribution Systems

Impulsive noise measurements were made on two electric distribution systems as part of Electric Power Research Institute Project RP1024-1, Study of Distribution System Surge and Harmonic Characteristics. This paper describes the instrumentation system used to measure impulsive noise conducted along, and emanated from, distribution lines in the 3-300-kHz frequency band. A significant source of this noise was identified as synchronously switched power converters. The concern is that such noise on distribution systems might cause interference to digital data carrier systems proposed for distribution systems. Test data from one of the utility systems are presented; potential problems caused by interference are discussed. Additional work utilizing the same or similar instrumentation on a relatively broad spectrum of distribution systems is recommended to identify and characterize impulsive noise.