Coil assembly of an integrated motor pump or turbine having reduced thermal stress at cryogenic temperatures

A method of manufacturing a coil assembly of an integrated motor pump (IMP) or integrated motor turbine (IMT), the method comprising:

• providing a plurality of winding cores;
• preparing a plurality of individual winding assemblies, wherein for each of the individual winding assemblies, said preparing of the individual winding assembly comprises:
• winding insulated wire about a hollow, non-metallic coil spool, the insulated wire being thereby formed into an electrical coil;
• placing the coil spool together with said electrical coil onto a fixture, said fixture having a shape that is substantially identical to a shape of a corresponding one of the plurality of winding cores;
• applying a first release agent to the electrical coil;
• applying a barrier material to surround and impregnate the electrical coil, such that said barrier material mechanically supports the electrical coil but is prevented by the first release agent from bonding to the electrical coil, the coil spool, electrical coil, and applied barrier material thereby forming the individual winding assembly;
• and
• removing the individual winding assembly from the fixture;
• for each of the winding cores, installing a corresponding one of the plurality of individual winding assemblies over the winding core, such that the winding core extends within and through a central cavity of the coil spool of the individual winding assembly, the individual winding assembly being constrained in location by the winding core without being bonded to the winding core;
• and
• forming a plurality of wired connections to the electrical coils, wherein the wired connections provide electrical communication among the electrical coils and/or between the electrical coils and an external power source or an external power receptor.