Electric Motor Cooling Bypass for Air Removal in Winding Heads
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing cooling systems for electrical machines in motor vehicles are not effective in managing gaseous components within the coolant, which reduces heat dissipation and cooling performance.
Innovation Solution
A cooling system with a bypass line that collects and removes gases from the winding head areas, using a dielectric liquid coolant that flows through sealed volumes around current-carrying components, including winding heads and power electronics, to enhance heat transfer and minimize thermal resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If a liquid coolant is used to cool the electric motor, then heat dissipation is improved, but gaseous components in the coolant reduce cooling performance
Solution Approach 1:
The bypass line extracts gaseous components from the coolant flow path. By providing a separate extraction path for gases at the highest points of the winding head areas, the system removes the harmful gaseous phase from the coolant, preventing gas accumulation that would reduce heat transfer efficiency and maintain effective cooling performance.
2Reliability
If the bypass line removes coolant flow to discharge gases, then gas collection is improved, but cooling capacity is reduced
Solution Approach 1:
The bypass line acts as an intermediary channel that separates the gas removal function from the main cooling flow path. It provides a dedicated route for gas extraction without significantly disrupting the primary coolant circulation, allowing gas discharge while maintaining adequate cooling capacity through the main cooling lines.
3Reliability
If the bypass line is dimensioned to force gas phase through, then gas removal is improved, but liquid coolant is discharged without cooling contribution
Solution Approach 1:
The bypass line extracts only the gaseous phase components from the coolant mixture at the highest points where gases accumulate. By targeting specifically the gas phase for removal through the bypass line, the system achieves effective gas discharge while minimizing the discharge of liquid coolant, thus reducing coolant loss.
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
The system improves heat transfer performance by reducing gaseous components in the coolant, allowing for effective cooling of electrical machines, especially in high-heat conditions, and eliminates the need for separate cooling of power electronics, thereby increasing the cooling capacity and efficiency.
Implementation Method 1
This minimizes thermal resistance between the current-carrying components, especially busbars, and the coolant, and enables high cooling performance
Implementation Method 2
the bypass line for collecting and/or removing air departs from the first winding head area at a point highest in the direction of gravity
Data Source
Figure 1
AI summary
A cooling system (10) for cooling an electric machine (12) of a motor vehicle is provided, comprising an access line (18) for supplying a cooled coolant to a first winding head area (22), at least one cooling line (30) leading from the first winding head area (22) through a stator (32) to a second winding head area (34), and a bypass line (36) leading from the first winding head area (22) to the second winding head area (34) past the stator (32), wherein the bypass line (36) for collecting and/or removing air departs from the first winding head area (22) at a point highest in the direction of gravity and/or enters the second winding head area (34) at a point highest in the direction of gravity.Although a portion of the liquid coolant is discharged via the bypass line (36) and does not participate in the cooling in the stator (32), the cooling capacity can be increased as a result of the gas phase carried along into the bypass line (36), thus enabling effective cooling of an electric machine (12) of a motor vehicle.