Power factor and quadergy definitions for harmonic rich power systems

The measurement of energy fed to electronically supplied machines can present problems if suitable meters are not used. The definition of quadergy (reactive energy) and power factor in an electrical system containing purely sinusoidally alternating voltages and currents is straightforward. However, when the waveforms become nonsinusoidal, complication arises as there then appears to be no fixed definition for quadergy/power factor, although `form factor´ and `load efficiency´ can be used to quantify the effect. The authors set out to explore the various possible definitions for quadergy/power factor for the general, not necessarily sinusoidal, case and to relate them to a set of criteria necessary for consistency and practicality. Once defined, microprocessor technology offers the means by which they can be implemented in making measurements