Basic Measuring Instruments

University of Texas System

W Mack Grady

Alexander McEachern

George P Olson

David Gerez

Gregorio C-y Chung

William Blane Leuschner

Ricardo Chan

A computer controllable testing and monitoring station forms short-term intervals of simulated alternating current power level disturbance, either undervoltage (sag) or overvoltage (swell). The station forms the short term voltage sags or swells so that their effects on sensitive equipment can be measured. The starting point of the sag or swell disturbance, as well as the time duration of the disturbance, can be accurately controlled.

Voltage sag/swell testing station

An electric power measuring system wherein power factor measurements are adjusted to reflect the adverse economic effects of harmonic currents and voltages. Well-known techniques are used to acquire frequency spectra that represent the voltages and currents present at the measuring point. These spectra are weighted in such a way that non-fundamental currents are increased and non-fundamental voltages are decreased. The weighted spectra are used to calculate a harmonic-adjusted volt-ampere measurement, which is then accumulated to form a harmonic-adjusted volt-ampere-hour measurement. The weighting functions for voltage and current are selected to approximate the economic impact on the AC power generating, transmission, and distribution system of non-fundamental currents and voltages. The resulting harmonic-adjusted volt-ampere-hour measurement is used to calculate a harmonic-adjusted power factor measurement.

Harmonic-adjusted power factor meter

An electric power measuring system wherein power factor measurements are adjusted to reflect the adverse economic effects of harmonic currents and voltages. Well-known techniques are used to acquire frequency spectra that represent the voltages and currents present at the measuring point. These spectra are weighted in such a way that non-fundamental currents are increased and non-fundamental voltages are decreased. The weighted spectra are used to calculate a harmonic-adjusted volt-ampere measurement, which is then accumulated to form a harmonic-adjusted volt-ampere-hour measurement. The weighting functions for voltage and current are selected to approximate the economic impact on the AC power generating, transmission, and distribution system of nonfundamental currents and voltages. The resulting harmonic-adjusted volt-ampere-hour measurement is used to calculate a harmonic adjusted power factor measurement.

Growing community of inventors

Round Rock, TX, United States of America

W Mack Grady