Harmonic-adjusted power factor meter
US5212441A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 25, 1992 |
| Grant date | May 18, 1993 |
| Priority date | — |
| Expiry date | Feb 25, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R21/006
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.