Power Measurements Under Nonsinusoidal Conditions : A Thesis in Electrical Engineering

This thesis was written in 1991 in partial fulfillment of the requirements for a Master of Science degree in Electrical Engineering at Wilkes University, Wilkes-Barre, Pennsylvania, United States. The measurement method discussed can be used to determine if the distortion is from the source, or caused by the load.

Abstract

A method is described for measuring real power in instances where voltage and current waveforms are not pure sinusoids. The measurement system utilizes digitized time domain samples of both waveforms. The waveforms are then transformed into the discrete frequency domain where both amplitude and phase information are derived.
This method can be used by electrical utility companies to survey harmonic content generated by loads in a power system. It also lends itself to applications of spectral analysis where in addition to amplitude information, phase information is also relevant.