Liquid cooling system for stacks of stator laminations of electrical machinery

Claim 2

A liquid cooling system for stacks of stator laminations of a turbogenerator having a stack of stator laminations divided by peripherally extending radial cooling slots into a plurality of axially adjacent component stacks of stator laminations, a plurality of flat hollow metal chamber sections adjusted to the laminations of the stack of stator laminations for cooling said stack of stator laminations, the chamber sections being inserted in the cooling slots in good thermal contact with said stack of stator laminations, each of the chamber sections comprising substantially a sector of an annulus comprising a pair of spaced parallel planar plates having yoke portions and alternate grooves and tooth portions formed therein in their area closer to the axis of the annulus; inlet means for supplying cooling liquid to tHe chamber section, outlet means for removing cooling liquid from the chamber section in a different area from that of the inlet means, said inlet and outlet means being connectable to a liquid coolant supply system, a plurality of cooling paths formed therein and extending in zigzag configuration from the inlet means via the yoke and tooth portions to the outlet means, and metal portions between the plates surrounding the cooling paths for absorbing the axial pressure exerted by the stack of stator laminations on the cooling system, a plurality of said chamber sections being adapted to be peripherally joined with each other in a cooling slot to form an annulus, each of the chamber sections having bores formed through the plates thereof for guiding therethrough tension rods of the stack of stator laminations and a liquidtight sealing path enclosing each of the bores and affixed to said plates and sealing the cooling system in the area of said bores from the outside, said liquid cooling system comprising a plurality of ledges forming the cooling paths and the metal portions surrounding said cooling paths of each of the chamber sections, said ledges being radially extending and axially aligned between the plates and comprising outer ledges in liquidtight relation with the plates and forming an outer wall for sealing the interior of each chamber section from the outside and inner ledges for guiding liquid coolant in each chamber section in a zigzag path from the inlet means to the outlet means via the yoke and tooth portions.

Claim 3

A liquid cooling system for stacks of stator laminations of turbogenerator having a stack of stator laminations divided by peripherally extending radial cooling slots into a plurality of axially adjacent component stacks of stator laminations, a plurality of flat hollow metal chamber sections adjusted to the laminations of the stack of stator laminations for cooling said stack of stator laminations, the chamber sections being inserted in the cooling slots in good thermal contact with said stack of stator laminations, each of the chamber sections comprising substantially a sector of an annulus comprising a pair of spaced parallel planar plates having yoke portions and alternate grooves and tooth portions formed therein in their area closer to the axis of the annulus, inlet means for supplying cooling liquid to the chamber section, outlet means for removing cooling liquid from the chamber section in a different area from that of the inlet means, said inlet and outlet means being connectable to a liquid coolant supply system, plurality of cooling paths formed therein and extending in zigzag configuration from the inlet means via the yoke and tooth portions to the outlet means, and metal portions between the plates surrounding the cooling paths for absorbing the axial pressure exerted by the stack of stator laminations on the cooling system, plurality of said chamber sections being positioned tangentially and peripherally joined with each other in a cooling slot to form an annulus, liquid coolant duct above the annulus and a liquid coolant duct below the annulus both extending in the longitudinal direction of the stack of stator laminations, the upper coolant duct supplying liquid coolant to the inlet means of the chamber sections and the lower coolant duct removing liquid coolant from the outlet means of the chamber sections, the liquid coolant flowing via the pressure paths formed by the inner and outer ledges in the chamber sections between the inlet means and outlet means thereof, said liquid cooling system comprising plurality of edges forming the cooling paths and the metal portions surrounding said cooling paths of each of the chamber sections, said edges being radially extending and axially aligned between the plates and comprising outer ledges in liquidtight relation with the plates and forming an outer wall for sealing the interior of each chamber section from the outside and inner ledges for guiding liquid coolant in each chamber section in a zigzag Path from the inlet means of the outlet means via the yoke and tooth portions.

Claim 4

A liquid cooling system for stacks of stator laminations of turbogenerator having a stack of stator laminations divided by peripherally extending radial cooling slots into a plurality of axially adjacent component stacks of stator laminations, a plurality of flat hollow metal chamber sections adjusted to the laminations of the stack of stator laminations for cooling said stack of stator laminations, the chamber sections being inserted in the cooling slots in good thermal contact with said stack of stator laminations, each of the chamber sections comprising substantially a sector of an annulus comprising a pair of spaced parallel planar plates having yoke portions and alternate grooves and tooth portions formed therein in their area closer to the axis of the annulus, inlet means for supplying cooling liquid to the chamber section, outlet means for removing cooling liquid from the chamber section in a different area from that of the inlet means, said inlet and outlet means being connectable to a liquid coolant supply system, plurality of cooling paths formed therein and extending in zigzag configuration from the inlet means via the yoke and tooth portions to the outlet means, and metal portions between the plates surrounding the cooling paths for absorbing the axial pressure exerted by the stack of stator laminations on the cooling system, plurality of said chamber sections being positioned tangentially and peripherally joined with each other in a cooling slot to form an annulus, liquid coolant duct above the annulus and a liquid coolant duct below the annulus both extending in the longitudinal direction of the stack of stator laminations, the upper coolant duct supplying liquid coolant to the inlet means of the chamber sections and the lower coolant duct removing liquid coolant from the outlet means of the chamber sections, the liquid coolant flowing via the pressure paths formed by the inner and outer ledges in the chamber sections between the inlet means and outlet means thereof, said liquid cooling system comprising plurality of edges forming the cooling paths and the metal portions surrounding said cooling paths of each of the chamber sections, said edges being radially extending and axially aligned between the plates and comprising outer ledges in liquidtight relation with the plates and forming an outer wall for sealing the interior of each chamber section from the outside and inner ledges for guiding liquid coolant in each chamber section in a zigzag Path from the inlet means of the outlet means via the yoke and tooth portions.

Claim 5

A liquid cooling system s claimed in claim 2, wherein the turbogenerator has a pair of end pressure plates and the stack of stator laminations extends intermediate the end pressure plates and wherein the annulus of chamber sections is inserted in a cooling slot of the stack of stator laminations closely adjacent an end pressure plate, and further comprising an annular inlet distribution duct substantially coaxial with the annulus and connected to the upper coolant duct, an annular outlet distribution duct connected to the lower coolant duct and a plurality of radially extending ducts connecting the inlet means of the chamber sections of the annulus to the inlet distribution duct in parallel and connecting the outlet means of the chamber sections of the annulus to the outlet distribution duct in parallel.

Claim 6

A liquid cooling system as claimed in claim 3, further comprising thermal insulating material positioned in the spaces between the substantially radially extending portions of the outer ledges which are in contact in peripheral direction to prevent direct metallic contact between annuli formed of chamber sections and electrically insulating material in the radially extending ducts and other connecting ducts.

Claim 7

A liquid cooling system as claimed in claim 2, wherein the annulus of chamber sections is inserted in a cooling slot of the stack of stator laminations spaced from he end pressure plates and wherein half the chamber sections of the annulus are positioned tangentially to form half an annulus and the other half the chamber sections of the annulus are positioned tangentially to form half an annulus, the chamber sections of each half an annulus being connected for liquid coolant flow in series, and further comprising ducts connecting the inlet means of the uppermost chamber section of each half annulus to the upper coolant duct and connecting he outlet means of the lowermost chamber section of each half annulus to the lower coolant duct, the two half annuli being connected to each other in parallel with regard to liquid coolant flow.

Claim 8

A liquid cooling system as claimed in claim 5, further comprising thermal insulating material positioned in the spaces between the substantially radially extending portions of the outer ledges which are in contact in peripheral direction to prevent direct metallic contact between annuli formed of chamber sections and electrically insulating material in the radially extending ducts and other connecting ducts.