Being a specialist in the field Power Products International will be called upon to create or improve a piece of equipment designed to very particular circumstance. The following is a brief case study of such an event; outlining the steps taken to fulfil the request of one particular client who wanted the most cost effective liquid cooled plate design for temperature control of a power converter for remote areas.
The client requested Power Products to investigate the most cost effective liquid cooled plate design for temperature control of a power converter used in remote locations with generator sets. With a requirement to dissipate nearly 5,000 watts, the design of the thermal management system would be a key factor in the success of the new project.
The converter design utilised multiple semiconductor devices, with varying power dissipation requirements. The mechanical design required the inlet and outlet of the coolant to be both located at the same end of the equipment.
In order to maximise the cooling characteristics, a design was proposed using a process called Controlled Atmosphere Brazing (CAB). This enables the diffusing channel design to be carefully matched to the areas directly beneath the components where the most effective heat transfer is required, and optimising the overall thermal flow characteristics of the cooling plate.
Examples of diffused channel machining showing concentration of cooling in areas directly beneath the heat sources.
This technique was selected to optimise the cooling at the higher power end of the heatsink.
This is the technology which allows the best customisation and variable geometry for the thermal solution. The assemblies can be in either aluminium or copper, and allow cooling on one or both sides of the plate. The assemblies are designed in 2 parts:
Firstly, a main base plate which will be machined with the optimum layout of cooling channels, including special features to create the best combination of smooth and turbulent flow in order to optimise the cooling effect around the high heat source areas.
Secondly a top plate which will be fitted over the machined base and sealed using a Controlled Atmosphere Brazing process. The process involves degreasing the surfaces and applying a brazing sheet of Aluminium / Silicon alloy, which is heated in a controlled vacuum to a liquid state, forming aluminium joints between the two parts of the assembly.
This technology gives the designer access to multiple geometries, without confining the solution to the existing heat sink profiles, or requiring labour intensive processes to insert tubes for the coolant. Once programmed into the machining centre, the design can be reproduced consistently and with lower life cycle costs.
Working closely with our technology partner Mecc.Al S.r.l. we have many design options available to us and our customers. If you have a new thermal management requirement, from simple liquid cooled plate extrusions to complex controlled atmosphere brazing techniques, we are able to provide the right technology and the expertise to make the product a reality. Call us now to discuss your next project – we can help to make it happen.