G - Physics – 01 – V
Patent
G - Physics
01
V
349/5
G01V 1/40 (2006.01) E21B 47/18 (2006.01)
Patent
CA 1106050
MEASURING-WHILE-DRILLING METHOD AND SYSTEM HAVING A DIGITAL MOTOR CONTROL ABSTRACT OF THE DISCLOSURE A measuring-while-drilling system has a digitally implemented motor speed control circuit for controlling a downhole, motor-driven acoustic signal generator. The acoustic generator is motor driven at speeds for imparting to well fluid an acoustic signal having phase states repre- sentative of encoded data derived from measured downhole conditions. The digital motor control circuit drives the motor at a substantially constant, carrier frequency pro- ducing speed in the absence of data of one logic state and temporarily changes the speed of the motor to effect a predetermined phase change in the carrier signal upon data of the predetermined logic state. For returning the motor speed to the carrier frequency producing speed during phase changes, the digital motor control circuit includes a first digital integrating circuit for providing a first digital signal having a value indicative of the constant value of the carrier frequency integrated over a time period be- ginning substantially upon the occurrence of the particular data; it has a second digital integrating circuit for providing a second digital signal having a value indicative of the instantaneous speed of the acoustic generator inte- grated over the time period; and it has a digital comparator which is responsive to the first and second digital signals for generating a control signal effective to change the speed of the motor when the difference between the first and second digital signals reaches a predetermined value.
285648
Bernard James I.
Strom Gerald A.
Schlumberger Technology Corporation
Smart & Biggar
LandOfFree
Digital motor control method and apparatus for... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Digital motor control method and apparatus for..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Digital motor control method and apparatus for... will most certainly appreciate the feedback.
Profile ID: LFCA-PAI-O-704924