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Old 10-18-2015, 03:37 PM   #2203 (permalink)
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I've been looking into some advanced cooling methods, mostly for the motor side of this problem. Here's some of the stuff I've found:

Direct spray cooling one of the most effective ways to cool stuff. In fact the military is actualy working on direct spray cooling. Here are a couple of interesting links about it:

An Overview of Liquid Coolants for Electronics Cooling « Electronics Cooling Magazine – Focused on Thermal Management, TIMs, Fans, Heat Sinks, CFD Software, LEDs/Lighting

Spray Cooling Electrical and Electronic Equipment - COTS Journal

In the first link, it mentions that a typical passively cooled motor can handle 5-8A/mm^2. A cooling jacket will allow about 10-15A/mm^2. The highest ratings were for direct spray cooling: 30A/mm^2.

In the second link, a bunch of sooper-dooper coolants are mentioned.

In the third link, the military's interest in the topic is illustrated:

Testing by Southern California Edison on a GE 85HP traction motor was significant and consistent with NAVSEA’s FIAL efficiency data. The GE 85HP traction motor was fully loaded and tested with air-cooling and spray cooling (Figure 2).

In the mid- to 3/4-loads, a 25% to 30% improvement in efficiency was reported with spray cooling. Also, a 10% improvement was reported at 85 HP load and a 15% improvement in sustained overload at 100 HP (total power, in direct contact with the liquid, exceeded 73,000 watts). The test rig and shaft were not designed to operate at higher loads; however, the designer indicated that sustained overloads of at least 200% of rated load were possible. The overload results show that the use of less costly, lighter and more efficient generators and motors in ship, air and spaceborne applications is possible with spray cooling.
Wow! a 25% to 30% increase in efficiency! Also a 200% increase in the rated load! I'm interested! For the inverter, between FOC, leading edge film capacitance, Silicon Carbide FET's, a planer bus and direct component cooling, we've got a killer app!

So, I think I figured out how to circulate coolant between the two plates. The top plate will have good seals to separate the coolant from the control board. The bottom plate won't and it will have a port to all0w the coolant to drain down to the capacitor. It can then pool around the capacitor before pulling it out and cooling it.

- E*clipse
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