Current injection via capacitive coupling
US10823869B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 28, 2016 |
| Grant date | Nov 3, 2020 |
| Priority date | — |
| Expiry date | Dec 27, 2036 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V3/24
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A casing has a plurality of joints of pipe joined by a plurality of casing collars, and an outer surface. A high-frequency alternating current (AC) source electrically is coupled to the casing. A coating of insulating material covers the entire outer surface of the casing. The coating has an opening that exposes a casing portion. The casing and the coating of insulating material define a capacitive electrode having an impedance Zf with a magnitude |Zf| at the frequency of operation f of the high-frequency AC source. Zf is low enough to allow current from the high-frequency AC source to be injected from the casing through the coating of insulating material into a surrounding formation. The casing portion has a resistance R to direct current (DC) with a magnitude that is very large compared to |Zf|.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.