Toroidal Inductor Cooling Cavity for Leakage-Safe Heat Transfer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Toroidal inductive devices face challenges in cooling, particularly in attaching a cooling element due to issues with leakage and evaporation when using conductive or non-conductive liquids, which can stress insulators and require additional measures.
Innovation Solution
A toroidal inductive device design featuring a toroidal core with windings where the outer perimeter conductor portions are straight and parallel, housed within a cylindrical cavity with non-circular cross-sections and axially directed grooves to enhance heat transfer, and a cooling element with a cylindrical cavity that matches the conductor's shape, using insulating material to fill gaps and incorporating cooling fins or ducts.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If a cooling element is attached to a toroidal inductive device using conductive cooling liquid, then cooling efficiency is improved, but insulator stress increases and leakage risks occur
Solution Approach 1:
The patent introduces an intermediary substance (insulating cooling liquid or phase change material) that mediates between the cooling requirement and insulation requirement. This intermediary allows heat transfer while maintaining electrical insulation, thus improving cooling efficiency without increasing insulator stress or leakage risks.
Solution Approach 2:
The cooling element is nested within the toroidal structure by placing it in the inner bore of the toroid, and the insulating material is nested between the cooling element and the winding. This nested arrangement allows the cooling system to be integrated without compromising the electrical insulation of the device.
2Reliability
If transformer oil or non-conductive cooling liquid is used, then insulator stress is reduced, but leakage and evaporation control measures are required
Solution Approach 1:
An insulating material is introduced as an intermediary between the cooling element and the winding, eliminating the need for complex leakage and evaporation control measures. This material allows the use of non-conductive cooling liquids without compromising insulation, thus reducing device complexity.
Solution Approach 2:
The patent employs flexible insulating materials (such as varnish or insulating漆) that can conform to the toroidal shape and sealing surfaces, providing effective sealing against leakage and evaporation without requiring rigid or complex sealing structures.
3Temperature
If a toroidal inductive device is immersed in cooling liquid, then cooling is achieved, but insulator stress increases due to electrical conductivity of the liquid
Solution Approach 1:
An electrical insulating material is introduced as an intermediary layer between the cooling liquid and the winding insulation. This intermediary allows the device to be immersed in conductive cooling liquid for effective cooling while protecting the insulator from electrical stress.
Solution Approach 2:
The patent applies different materials with different properties to different parts of the device: the outer surface is coated with insulating material for electrical protection, while the inner bore contains the cooling element for thermal management. This local differentiation allows simultaneous achievement of cooling effectiveness and insulator reliability.
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 design improves heat transfer efficiency while minimizing leakage risks and evaporation, effectively addressing cooling challenges in toroidal inductive devices.
Implementation Method 1
a cooling element in the form of a cylindrical rod or a cylindrical cavity containing the toroidal core and the electric conductor
Implementation Method 2
The inductive device may comprise a phase change material for cooling the inductive device
Implementation Method 3
The toroidal core is advantageously a magnetically amplifying core which comprises ferromagnetic material. A toroidal inductive device can be for example a part of a filter circuit or an energy storage component of a power electronic converter
Implementation Method 4
at least one electric conductor wound around the toroidal core and constituting at least one winding
Data Source
AI summary
An inductive device comprises a toroidal core and at least one electric conductor wound around the toroidal core and constituting at least one winding. The inductive device comprises a cooling element constituting a cylindrical cavity that contains the toroidal core and the electric conductor so that the axial direction of the toroidal core is parallel with the axial direction of the cylindrical cavity. The shape of the cylindrical cavity and the cross-section of the electric conductor are adapted to match each other to improve heat transfer from the electric conductor to the wall of the cylindrical cavity so that a wall of the cylindrical cavity is provided with axially directed grooves occupied by portions of the electric conductor on an outer perimeter of the winding.