Method and apparatus for transmitting sensor response data and power through a mud motor

Abstract

Apparatus and methods for establishing electrical communication between an instrument subsection disposed below a mud motor and an electronics sonde disposed above the mud motor in a drill string conveyed borehole logging system. Electrical communication is established via at least one conductor disposed within the mud motor and connecting the instrument sub section to a link disposed between the mud motor and the electronics sonde. The link can be embodied as a current coupling link, a magnetic coupling link, an electromagnetic telemetry link and a direct electrical contact link. Two way data transfer is established in all link embodiments. Power transfer is also established in all but the electromagnetic telemetry link.

1 . A borehole hole assembly system comprising: 
 (a) an instrument sub;    (b) an electronics sub comprising an electronics sonde;    (c) a mud motor disposed between said instrument sub and said electronics sub; and    (d) a conductor disposed in said mud motor with a lower terminus electrically connected to said instrument sub and an upper terminus electrically connected to a link disposed between said mud motor and said electronics sonde, wherein    (e) said instrument sub is rotatable with respect to said electronics sub; and    (g) said link provides operational coupling between said instrument sub and said electronics sonde.    
   
   
       2 . The system of  claim 1  wherein said link comprises: 
 (a) an upper electromagnetic transceiver; and    (b) a lower electromagnetic transceiver rotatable with respect to said upper electromagnetic transceiver; wherein    (c) said operational coupling is provided by electromagnetic transmission between said lower magnetic transceiver and said upper electromagnetic transceiver.    
   
   
       3 . The system of  claim 1  wherein said link comprises: 
 (a) at least one conducting ring disposed around and electrically insulated from an upper end of a flex shaft extending into said electronics sub; and    (b) means for electrically contacting said at least one conducting ring;    (c) wherein said at least one conducting ring rotates with respect to said brush; and    (d) said at least one conducting ring and said contacting means provide said operational coupling by direct electrical contact.    
   
   
       4 . The system of  claim 1  wherein said link comprises: 
 (a) an upper magnetic dipole; and    (b) a lower magnetic dipole rotatable with respect to said upper magnetic dipole; wherein    (c) said upper and lower magnetic dipoles provide said operational coupling by magnetic coupling.    
   
   
       5 . In a bottom hole assembly, a method for operationally coupling an instrument sub and an electronics sub with a mud motor disposed there between, the method comprising: 
 (a) disposing a conductor in said mud motor with a lower terminus electrically connected to said instrument sub and an upper terminus electrically connected to a link disposed between said mud motor and said electronics sonde, wherein    (b) said instrument sub is rotatable with respect to said electronics sub; and    (c) said link provides said operational coupling between said instrument sub and said electronic sonde.    
   
   
       6 . The method of  claim 5  wherein said link is provided by: 
 (a) providing an upper electromagnetic transceiver that is fixed with respect to said electronics sub; and    (b) providing a lower electromagnetic transceiver rotatable with respect to said upper electromagnetic transceiver; wherein    (c) said operational coupling is provided by electromagnetic transmission between said lower magnetic transceiver and said upper electromagnetic transceiver.    
   
   
       7 . The method of  claim 5  wherein said link is provided by: 
 (a) disposing at least one conducting ring around an upper end of a flex shaft extending into said electronics sub and electrically insulating said conducting ring from; and    (b) electrically contacting said at least one conducting ring a brush; wherein    (c) said at least one conducting ring rotates with respect to said brush; and    (d) said at least one conducting ring and said contacting brush provide said operational coupling by direct electrical contact.    
   
   
       8 . The method of  claim 5  wherein said link is provided by: 
 (a) operationally connecting an upper magnetic dipole to said electronics sonde; and    (b) operationally connecting a lower magnetic dipole to a rotor element of said mud motor, wherein;    (c) said lower magnetic dipole is rotatable with respect to said upper magnetic dipole; and    (d) said upper and lower magnetic dipoles provide said operational coupling by magnetic coupling.