The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 03, 2012
Filed:
Apr. 12, 2010
Marian L. Morys, Downington, PA (US);
William J. Schaecher, Houston, TX (US);
George D. Goodman, Pheonixville, PA (US);
Raj Pai, Houston, TX (US);
Marian L. Morys, Downington, PA (US);
William J. Schaecher, Houston, TX (US);
George D. Goodman, Pheonixville, PA (US);
Raj Pai, Houston, TX (US);
Halliburton Energy Services, Inc., Houston, TX (US);
Abstract
An apparatus and method for minimizing the effects of a common mode voltage signal in downhole logging tools utilized to determine the resistivity of an adjacent portion of a borehole wall. Two current electrodes are energized by an excitation source to create an oscillatory electric field in a borehole wall. A voltage drop across a segment of the borehole wall is measured by two voltage electrodes, and the differential voltage is used in combination with a measured current flow to determine a resistivity value for the borehole wall. A common mode voltage in front of the two voltage electrodes is measured and minimized by controlling the excitation source, thereby reducing the resistivity measurement error.