A turbogenerator includes a stator core defining a first end and a second end, a plurality of stator bars disposed within the stator core, each stator bar including a coolant flow path, and a parallel ring having a first segment and a second segment separate from the first segment. The parallel ring is coupled to the first end of the stator core and is arranged to electrically connect the plurality of stator bars and to fluidly connect the coolant flow paths of the plurality of stator bars. A tang includes a main chamber, a first coolant opening, a second coolant opening, and a distribution channel that fluidly interconnects the main chamber, the first coolant opening, and the second coolant opening. A first lead tube has a first lead end connected to the first coolant opening and a second lead end connected to the first segment, and a second lead tube separate from the first lead tube has a first lead end connected to the second coolant opening and a second lead end connected to the second segment. The plurality of stator bars, the parallel ring, the tang, the first lead tube, and the second lead tube cooperate to define a portion of a circuit and a portion of a cooling path.

A stator winding includes: a plurality of stator bars and a connection structure. Each of the stator bars penetrates each of the stator slots and includes at least one hollow element wire, wherein inside the at least one hollow element wire a flow hole for a cooling medium is formed. A connection structure includes: a sleeve whose axial one end is fitted to a vicinity of an end of the stator bar; a closing plate disposed at another end of the sleeve; and a hollow extension pipe. The hollow extension pipe is disposed in a space defined by the sleeve and the closing plate at the end of the stator bar, and makes the flow hole of the hollow element wire and an outside of the space communicate each other. A brazing material is filled in the space.

A method for sealing fluid cooled conduits in-situ for a generator is provided. The fluid or liquid cooled conduits are located external to a stator of the generator and substantially outward of stator bars. The method includes draining coolant from the fluid cooled conduits, and drying interior surfaces of the fluid cooled conduits. In inserting step inserts a borescope and a sealant applicator through an opening in one of the fluid cooled conduits. A locating step locates a brazed joint in the fluid cooled conduit, and a positioning step positions the borescope and the sealant applicator near the brazed joint. An applying step applies a sealant to the inside of the fluid cooled conduit at the brazed joint A viewing step may be used to view the brazed joint with the borescope to confirm that the applying step has been successful.

An electromechanical flywheel machine includes a flywheel mass and a motor-generator having a rotor rotatable about a stationary inner stator having stator windings.

A joined component comprises a first heated body, a second heated body, a brazing material, a first heated portion and a second heated portion. The first body comprises an insertion opening and an inserted portion coupled with the insertion opening. The second body comprises an insertion portion inserted into the inserted portion through the insertion opening. The first heated portion is provided at a first position including at least a part of the inserted portion and at least a part of the insertion portion. The second heated portion is provided at a second position separate from the insertion portion where a ratio “L/D” satisfies being 0.4 or more and 0.8 or less, where “L” is a length from the insertion opening to the second portion and “D” is an outer diameter of the second heated body.

A method includes: forming a sand core including a main portion and core-head members connecting the main portion; applying a casting process to produce a frame casting having a first end, a first-end inner wall, a second end, a second-end inner wall, a closed water channel between the first-end inner wall and the second-end inner wall, a water inlet, a water outlet and sand-expelling holes at the first end; shaking the frame casting to have part of the sand core to leave the closed water channel via the water inlet, the water outlet and the sand-expelling holes; pressurizing a fluid into the closed water channel via the water inlet to carry the rest of the sand core to leave the closed water channel via the sand-expelling holes and the water outlet; and applying screw bolts to lock the sand-expelling holes to manufacture a closed-type and liquid-cooling motor frame.

A method for repairing solder joint leakages on a connection unit designed to feed cooling water into hollow metallic stator bars of a stator winding of an electrical machine. A welding or soldering apparatus is designed for carrying out the method.

The invention relates to an electric machine (1) having: a rotor (3); a stator (2); multiple winding pieces (5) which are in the form of hollow conductors, form different coils of a winding (4) of the electric machine (1) and are each part of a coolant circuit of the electric machine (1); and multiple external phase connections (L1-L3) which are electrically connected to the winding pieces (5). According to the invention, a hydraulic connection part (15) to which a number of the winding pieces (5) are hydraulically connected, and a seal (27) which has multiple passages (28), in each of which an end portion (8) of one of the winding pieces (5) is situated, are provided, the hydraulic connection part (15) and the seal (27) having opposing surfaces (29, 30) which rest against each other in order to ensure sealing of the individual connections of the winding pieces (5) to the hydraulic connection part (15).

A water chamber cover for connecting a water hose to a water chamber bottom plate of a directly water-cooled stator bar, having a peripheral groove, which is open on a side facing away from the water chamber and which is designed to hold the water hose. A method is for assembling a cooling water circuit for a directly water-cooled stator bar.

A turbogenerator includes a stator core defining a first end and a second end, a plurality of stator bars disposed within the stator core, each stator bar including a coolant flow path, and a parallel ring having a first segment and a second segment separate from the first segment. The parallel ring is coupled to the first end of the stator core and is arranged to electrically connect the plurality of stator bars and to fluidly connect the coolant flow paths of the plurality of stator bars. A tang includes a main chamber, a first coolant opening, a second coolant opening, and a distribution channel that fluidly interconnects the main chamber, the first coolant opening, and the second coolant opening. A first lead tube has a first lead end connected to the first coolant opening and a second lead end connected to the first segment, and a second lead tube separate from the first lead tube has a first lead end connected to the second coolant opening and a second lead end connected to the second segment. The plurality of stator bars, the parallel ring, the tang, the first lead tube, and the second lead tube cooperate to define a portion of a circuit and a portion of a cooling path.