Electrical Submersible Pump with Motor Winding Encapsulated in Bonded Ceramic

Abstract

An electrical submersible pump assembly has a motor with a stator stack of limitations. The stack has slots through which magnet wires are wound. An encapsulate surrounds and bonds the magnet wires together within each slot. The encapsulate includes ceramic particles within a polymer adhesive matrix. The polymer matrix may be a fluoropolymer adhesive. Each of the magnet wires may have an electrical insulation layer surrounding a copper core. The ceramic particles are rounded and much smaller than a cross-sectional area of each of the magnet wires. At least some of the magnet wires may be in contact with a perimeter of the slot. The polymer matrix fills all voids within each of the slots. The ceramic particles may be porous.

1 . An electrical submersible pumping (“ESP”) assembly comprising:
 a pump driven by an electrical motor; 
 the motor having a stack of stator laminations, the stator laminations having slots formed therethrough; 
 magnet wires wound through the slots; and 
 an encapsulate that bonds the magnet wires within each of the slots together, the encapsulate comprising ceramic particles bonded together within a polymer matrix. 
 
     
     
         2 . The ESP assembly of  claim 1 , wherein the ceramic particles have a size of 20 mesh to 140 mesh. 
     
     
         3 . The ESP assembly of  claim 1 , wherein the polymer matrix comprises a fluoropolymer that is selected from a group consisting of perfluoroalkoxy (“PFA”), fluorinated ethylene propylene (“FEP”), polytetrafluoroethylene (“PTFE”), and combinations thereof. 
     
     
         4 . The ESP assembly of  claim 1 , wherein each of the magnet wires comprises an electrical insulation layer surrounding a copper core. 
     
     
         5 . The ESP assembly of  claim 1 , wherein the ceramic particles are generally spherical. 
     
     
         6 . The ESP assembly of  claim 1 , wherein each of the ceramic particles has a cross-sectional area much smaller than a cross-sectional area of each of the magnet wires. 
     
     
         7 . The ESP assembly of  claim 1 , wherein:
 each of the slots has a perimeter; and   at least some of the magnet wires are in contact with the perimeter.   
     
     
         8 . The ESP assembly of  claim 1 , wherein:
 the polymer matrix fills all voids within each of the slots.   
     
     
         9 . The ESP assembly of  claim 1 , wherein:
 the polymer matrix is formed of an electrical insulation material.   
     
     
         10 . The ESP assembly of  claim 1 , wherein the ceramic particles are porous. 
     
     
         11 . An electrical submersible pumping (ESP) assembly, comprising:
 a pump driven by an electrical motor, the motor comprising:   a housing having a longitudinal axis;   a slack of stator laminations stacked on each other within the housing, the stack of stator laminations having an axial opening and a plurality of slots spaced circumferentially around the opening;   magnet wires wound through each of the slots in the stack, each of the magnet wires having a conductive core encased in an electrical insulation layer;   a polymer matrix of an electrical insulation material bonding the magnet wires within each of the slots together; and   ceramic particles dispersed throughout and bonded within the polymer matrix.   
     
     
         12 . The ESP assembly according to  claim 11 , wherein:
 the polymer matrix comprises a fluoropolymer adhesive.   
     
     
         13 . The ESP assembly according to  claim 11 , wherein:
 the ceramic particles have a size of 20 mesh to 140 mesh.   
     
     
         14 . The ESP assembly of  claim 11 , wherein the polymer matrix comprises a fluoropolymer that is selected from a group consisting of perfluoroalkoxy (“PFA”), fluorinated ethylene propylene (“FEP”), polytetrafluoroethylene (“PTFE”), and combinations thereof. 
     
     
         15 . The ESP assembly of  claim 11 , wherein the ceramic particles are generally spherical. 
     
     
         16 . The ESP assembly of  claim 11 , wherein:
 each of the slots has a perimeter;   at least some of the magnet wires are in contact with the perimeter; and   a portion of the polymer matrix is in contact with the perimeter.   
     
     
         17 . An electrical submersible pumping (ESP) assembly, comprising:
 a pump driven by an electrical motor, the motor comprising:   a housing having a longitudinal axis;   a stack of stator laminations stacked on each other within the housing;   the stack of stator laminations having an axial opening and a plurality of slots spaced circumferentially around the opening;   magnet wires wound through each of the slots in the stack, each of the magnet wires having a conductive core encased in an electrical insulation layer;   a rotor extending along the axis through the opening in the stack;   a fluoropolymer adhesive matrix bonding all of the magnet wires within each of the slots together; and   ceramic particles dispersed throughout and bonded within the fluoropolymer adhesive matrix, each of the ceramic particles being generally spherical and having a much smaller cross-sectional than each of the magnet wires.   
     
     
         18 . The ESP assembly of  claim 17 , wherein the fluoropolymer adhesive matrix comprises a fluoropolymer that is selected from a group consisting of perfluoroalkoxy (“PFA”), fluorinated ethylene propylene (“FEP”), polytetrafluoroethylene (“PTFE”), and combinations thereof. 
     
     
         19 . The ESP assembly of  claim 17 , wherein:
 each of the slots has a perimeter;   at least some of the magnet wires are in contact with the perimeter; and   the fluoropolymer adhesive matrix is bonded to the perimeter and fills all voids in each of the slots.   
     
     
         20 . The ESP assembly of  claim 17 , wherein:
 the ceramic particles are porous.