Stator Cooling via Embedded Plastic Compound Ducts

Solution Overview

Problem

Conventional electrical machines require significant structural effort and increased production costs to achieve efficient heat transfer from stator windings to coolants, which can lead to overheating and damage.

Innovation Solution

Embedding stator windings and cooling ducts into a high thermal conductivity electrically insulating plastic compound, allowing for direct thermal coupling and effective heat transfer while preventing electrical short-circuits, using injection molding for production efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If conventional cooling devices with separate cooling ducts are used, then heat transfer from stator to coolant is achieved, but structural effort and production costs increase significantly

Engineering Contradiction:

Improveheat transfer efficiencyVSAvoidstructural effort

Core Design Contradiction:

TemperatureVSDevice complexity

Solution Approach 1:

The patent merges the cooling duct structure with the stator windings by embedding the cooling ducts directly into the stator core. This integration eliminates the need for separate, complex cooling device structures while maintaining effective heat transfer from the stator windings to the coolant flowing through the embedded ducts.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The patent employs composite construction by integrating the cooling ducts within the stator assembly, creating a combined structure where the stator and cooling system function as a unified component. This reduces the number of separate parts and simplifies the overall device structure while preserving cooling functionality.

Inventive Principle:

Principle #40Composite materials

2Temperature

If conventional cooling devices with separate cooling ducts are used, then heat transfer from stator to coolant is achieved, but production costs increase

Engineering Contradiction:

Improveheat transfer efficiencyVSAvoidproduction costs

Core Design Contradiction:

TemperatureVSEase of manufacture

Solution Approach 1:

The patent merges the cooling duct structure with the stator windings by embedding the cooling ducts directly into the stator core. This integration eliminates the need for separate, complex cooling device structures while maintaining effective heat transfer from the stator windings to the coolant flowing through the embedded ducts.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The patent employs composite construction by integrating the cooling ducts within the stator assembly, creating a combined structure where the stator and cooling system function as a unified component. This reduces the number of separate parts and simplifies the overall device structure while preserving cooling functionality.

Inventive Principle:

Principle #40Composite materials

3Reliability

If stator windings are cooled efficiently, then overheating and damage are prevented, but structural complexity increases

Engineering Contradiction:

Improveprotection from overheatingVSAvoidstructural effort

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent merges the cooling duct structure with the stator windings by embedding the cooling ducts directly into the stator core. This integration eliminates the need for separate, complex cooling device structures while maintaining effective heat transfer from the stator windings to the coolant flowing through the embedded ducts.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The stator structure itself provides the cooling function through embedded ducts, making the cooling system an inherent part of the stator rather than an external addition. This self-integrated approach ensures reliable heat dissipation while avoiding the complexity of separate cooling device assemblies.

Inventive Principle:

Principle #25Self-service

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 approach enhances cooling efficiency, reduces production costs, and prevents overheating, ensuring effective heat dissipation and prolonged machine lifespan.

Implementation Method 1

Heat can be dissipated from the stator by means of heat transfer from the stator windings to the coolant

Methodology Applied

Scientific EffectHeat transfer: Conduction (thermal)

Implementation Method 2

Heat can be dissipated from the stator by means of heat transfer from the stator windings to the coolant

Methodology Applied

Scientific EffectHeat transfer: Conduction (thermal)

Data Source

PatentUS11190063B2Electrical machine

Publication Date: 2021.11.30 MAHLE INT GMBH

AI summary

An electrical machine may include a rotor rotatable about an axis of rotation which defines an axial direction, a stator including a plurality of stator windings, a coolant collector chamber, and a coolant distributor chamber fluidically communicating with the coolant collector chamber via at least one cooling duct. At least one stator winding may be embedded into a plastic compound composed of an electrically insulating plastic. The stator may further include a stator body having a space. The at least one cooling duct may be arranged in the stator body and may be at least partially defined by at least one aperture disposed in the stator body through which the coolant is flowable. The at least one aperture may open towards the space and may be closed in a fluid-tight manner via the plastic compound.