Waste heat utlization system and method of manufacturing a generator component

Abstract

A waste heat utilization system including a generator configured to receive a flow of an organic working fluid and a method of manufacturing the generator component is provided. The method includes preheating the generator component. The method also includes applying a varnish or an encapsulating layer to the generator component. The method further includes baking the generator component with the varnish applied thereto. The method yet further includes cooling the generator component.

1 . A waste heat utilization system comprising:
 a generator configured to receive a flow of an organic working fluid, wherein the generator comprises:
 a stator; 
 a permanent magnet rotor configured to rotate within the stator to generate electricity; 
 at least one generator component positioned to be exposed to the flow of the organic working fluid; and 
 at least one protective layer disposed on the at least one generator component, wherein the at least one protective layer is configured to withstand exposure to the organic working fluid to inhibit contact between the at least one generator component and the organic working fluid. 
   
     
     
         2 . The waste heat utilization system of  claim 1 , wherein the at least one protective layer comprises a varnish having a composition comprising:
 at least 50% by weight of aromatic backbone epoxy resin;   at least 10% by weight of aliphatic epoxy resin;   less than 15% by weight of a reactive diluent; and   less than or equal to 10% by weight of a catalyst and a crosslinking agent.   
     
     
         3 . The waste heat utilization system of  claim 2 , wherein the varnish composition comprises:
 50%-70% by weight of aromatic backbone epoxy resin;   10%-20% by weight of aliphatic epoxy resin;   less than or equal to 15% by weight of the reactive diluent; and   1%-10% by weight of the catalyst and crosslinking agent.   
     
     
         4 . The waste heat utilization system of  claim 1 , wherein the at least one protective layer comprises an encapsulant having a composition comprising:
 at least 50% by weight of an inorganic filler content; and   at least 10% by weight of an epoxy softening agent.   
     
     
         5 . The waste heat utilization system of  claim 1 , wherein the at least one generator component comprises at least one of a stator winding, an end turn, a magnetic bearing, and a stator casing, and wherein the at least one generator component is configured to be operated in an integrated power module of an organic Rankine cycle system, wherein the protective layer has a temperature index of at least 155 degrees Celsius. 
     
     
         6 . A method of manufacturing a generator component comprising:
 preheating the generator component;   applying a varnish to the generator component;   baking the generator component with the varnish applied thereto; and   cooling the generator component.   
     
     
         7 . The method of  claim 6 , wherein the varnish is applied directly to the generator component. 
     
     
         8 . The method of  claim 6 , wherein the varnish is applied indirectly to the generator component with a cloth disposed therebetween. 
     
     
         9 . The method of  claim 6 , wherein the generator component comprises at least one of a stator winding, an end turn, a magnetic bearing, and a stator casing. 
     
     
         10 . The method of  claim 6 , wherein the generator component is preheated to a preheating temperature ranging from 70 degrees Celsius to 130 degrees Celsius. 
     
     
         11 . The method of  claim 6 , wherein the varnish is applied to the generator component by submerging the generator component in a varnish bath for about 30 minutes for impregnating the generator component with the varnish. 
     
     
         12 . The method of  claim 11 , wherein the generator component is submerged in the varnish bath by at least 0.25 inches below a surface of the varnish bath. 
     
     
         13 . The method of  claim 6 , wherein baking the generator component comprises heating the generator component for at least about 3 hours at a temperature of about 160 degrees Celsius. 
     
     
         14 . The method of  claim 6 , further comprising a post-curing heating of the generator component for 4 hours to 12 hours at a temperature of 120 degrees Celsius to 130 degrees Celsius. 
     
     
         15 . The method of  claim 6 , further comprising rotating the generator component to different positions during baking of the generator component. 
     
     
         16 . The method of  claim 6 , further comprising encapsulating the generator component with an encapsulant. 
     
     
         17 . The method of  claim 6 , further comprising installing the generator component in an integrated power module configured to be operated in an organic Rankine cycle system. 
     
     
         18 . A method of manufacturing a generator component comprising:
 placing the generator component in a mold, wherein the generator component comprises at least one of a stator winding, an end turn, a magnetic bearing, and a stator casing;   disposing an encapsulant proximate the generator component while the generator component is in the mold; and   cooling the generator component with the encapsulant applied thereto.   
     
     
         19 . The method of  claim 18 , further comprising disposing the encapsulant directly onto an exterior surface of the generator component. 
     
     
         20 . The method of  claim 18 , further comprising:
 applying an intermediate material to an exterior surface of the generator component, wherein the intermediate material comprises at least one of a varnish and a cloth; and   disposing the encapsulant onto the intermediate material.