Direct current measuring apparatus and method employing flux diversion
US5701073A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 28, 1996 |
| Grant date | Dec 23, 1997 |
| Priority date | — |
| Expiry date | Feb 28, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R15/20
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A current probe (10) measures a signal current flowing in a conductor (12), which produces a signal flux (14) proportional to the signal current. The probe includes a pair of probe arms (16, 18) that straddle the conductor, a flux shunt (20), a pair of flux diverting arms (22, 24), and a flux link (26). A Hall-effect device (28) senses the amount of flux flowing in the flux shunt. A major portion of the signal flux flows in a preferential path (30) through the flux shunt while a minor portion flows in a flux diverting path (32). The ratio of the amount of the signal flux flowing in the preferential flux path to the diverting path depends on the reluctance in each path, which is determined by air gaps (27, 34). The Hall-effect device drives a current source (40) that provides a diverter current through a pair of flux diverting coils (42, 44) that are wound around flux diverting arms (22, 24) of the current probe. The diverter current produces in the flux diverting path a diverting flux (46) that diverts the signal flux from the flux shunt. The signal current is measured by determining the amount of diverter current required to completely divert the signal flux flowing in the flux sh…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.