Harmonic measuring instrument for AC power systems with latched indicator means
US5298888A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 21, 1992 |
| Grant date | Mar 29, 1994 |
| Priority date | — |
| Expiry date | Aug 21, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R23/165
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An instrument for measuring voltage harmonics and current harmonics on AC (alternating current) power systems. The instrument includes the ability to determine when threshold limits have been exceeded for harmonics. The instrument also includes timing thresholds whose inputs are activated when the harmonic thresholds are exceeded. A single harmonic threshold is applied to measurements from multiple phases on poly-phase systems by comparing the square root of the sum of the squares of measurements from each phase to the harmonic threshold. Three indicators show when voltage harmonic limits are exceeded, current harmonics limits are exceeded, or both voltage and current harmonic limits are exceeded simultaneously.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.