Direct Submersion Cooling for Power Electronics
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The high cost of adding liquid cooling to vehicles with direct cooling of power electronics using dielectric fluid and the additional expense of complex heat exchangers to transfer heat to engine coolant without exposing electronics to ionic contamination.
Innovation Solution
A housing assembly with a plate, circuit board, heat spreaders, epoxy material region, and Parylene coating layer that allows direct submersion of electronics into circulated engine coolant, providing a fluidic seal and electrical connections while protecting against contamination.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If dielectric fluid is used for direct cooling of power electronics, then cooling effectiveness is improved, but system cost increases
Solution Approach 1:
The patent makes the engine coolant serve a dual function: cooling the engine and directly cooling the power electronics. By allowing the coolant to contact both the engine and the electronics (through a sealed enclosure with thermal coupling), the system eliminates the need for separate dielectric fluid and associated heat exchangers, thereby reducing system cost while maintaining cooling effectiveness.
2Object-affected harmful factors
If heat exchangers are added to transfer heat from electronics to engine coolant, then electronics are protected from ionic contamination, but device complexity and cost increase
Solution Approach 1:
The patent introduces a sealed enclosure (housing) as an intermediary barrier between the power electronics and the engine coolant. This enclosure allows thermal energy to pass through (via thermal coupling or conduction) while preventing ionic contamination from reaching the electronics. The sealed enclosure acts as a mediator that enables heat transfer protection without requiring complex active heat exchanger systems.
3Object-affected harmful factors
If sealed enclosures are used to protect electronics from coolant, then contamination is prevented, but thermal coupling efficiency decreases
Solution Approach 1:
The patent employs a sealed enclosure with thin-walled construction that provides contamination protection while maintaining effective thermal coupling. The thin walls of the sealed enclosure allow heat to conduct through efficiently while still providing the necessary barrier against ionic contamination. This approach balances protection needs with thermal performance without requiring complex heat exchanger geometries.
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
Enables effective liquid cooling of power electronics using readily available engine coolant, preventing leakage and contamination while maintaining high power dissipation capabilities.
Implementation Method 1
The ParyleneTM coating layer is deposited in a manner effective to protect the electronic device from the engine coolant
Implementation Method 2
The first heat spreader is fixedly attached to a first planar side of the electronic device... The second heat spreader is fixedly attached to a second planar side of the electronic device
Implementation Method 3
The epoxy material region is dispensed around the leads in a manner effective to mechanically secure the arrangement to the plate and prevent engine coolant leakage around the leads
Data Source
AI summary
An assembly for liquid cooling electronics by direct submersion into circulated engine coolant that includes an epoxy material dispensed around leads of electronics devices in a manner effective to mechanically secure the electronics devices to the assembly and prevent engine coolant leakage around the leads, and a Parylene™ coating layer deposited in a manner effective to protect the electronic device from electrically conductive engine coolant such as ethylene glycol. Such an assembly is useful in hybrid electric vehicles that have engine coolant available from the vehicle's internal combustion engine.