Winding Overhang Cooling with Radial Flow Guide Elements
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Electrical machines with a stator winding overhang face challenges in achieving uniform cooling due to hot spots caused by uneven heat distribution, leading to potential damage from excessive heating during operation.
Innovation Solution
The implementation of guiding elements arranged in a distributed manner along the circumferential direction within the coolant shaft redirects the fluid flow from a circumferential to a radial direction, ensuring uniform distribution of cooling fluid across the winding overhang, even with asymmetric supply, thereby preventing hot spots.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If the heat exchanger is arranged outside the rotation axis in an upper, lower, or lateral region of the stator, then the machine structure is simplified and easier to manufacture, but individual winding overhang regions are spaced farther apart from the heat exchanger, resulting in non-uniform cooling and hot spots
Solution Approach 1:
The coolant shaft is divided into multiple cooling sections with individually controllable coolant supply. Each section can be independently regulated to direct cooling fluid to specific regions of the winding overhang, enabling uniform cooling distribution despite the heat exchanger's external position.
Solution Approach 2:
Different regions of the winding overhang receive customized cooling based on their specific thermal requirements. The coolant shaft incorporates region-specific cooling channels and flow control mechanisms that adapt the cooling intensity and distribution to local heat generation patterns, preventing hot spots in distal regions.
2Device complexity
If cooling fluid is supplied asymmetrically from one side to the coolant shaft, then the device complexity is reduced, but the cooling fluid does not reach the side of the winding overhang facing away from the inflow side effectively, causing hot spots
Solution Approach 1:
The coolant shaft incorporates circumferential flow channels that redirect the cooling fluid from axial flow to radial flow, distributing the coolant in the circumferential direction. This dimensional transformation of flow direction enables the cooling fluid to reach all sides of the winding overhang, including regions facing away from the inflow side, without requiring multiple asymmetric supply points.
Solution Approach 2:
The coolant shaft acts as an intermediary distribution system between the single-point coolant supply and the winding overhang. It incorporates internal flow redistribution mechanisms including radial flow channels and circumferential distribution paths that evenly dispers the cooling fluid to all required regions, effectively decoupling the supply asymmetry from the cooling coverage.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This solution achieves a uniform cooling of the winding overhang, preventing hot spots and ensuring effective heat dissipation, even when the cooling fluid supply is asymmetric, thus enhancing the machine's operational reliability and longevity.
Implementation Method 1
a cooling fluid also reaches a side of the winding overhang facing away from an inflow side, from which the cooling fluid enters the coolant shaft, and that said side is also cooled
Implementation Method 2
the heat exchanger, normally embodied as an air-to-water heat exchanger, is typically arranged below a laminated stator core
Data Source
AI summary
Electrical machine, e.g., a generator, having a stator comprising a winding overhang, a rotor arranged rotatable in the stator, and a heat exchanger fluidically connected to the winding overhang via a coolant shaft, which is arranged radially outside the winding overhang, runs at least partially approximately along a circumferential direction, and is delimited in a radial direction by an outer surface, so that the winding overhang can be cooled by a continuous flow of a fluid over the heat exchanger and the winding overhang. To obtain uniform cooling of the winding overhang, multiple guiding elements are arranged in a distributed manner along a circumferential direction in the coolant shaft to redirect a flow of a fluid oriented in a circumferential direction in the coolant shaft at least partially into a radial flow towards the winding overhang and to distribute the flow to multiple regions of the winding overhang.