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Power Electronics Power Supply

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I am building, hopefully, a power supply with the following primary specs. 

1. Powered from a 15 or 20 ampere receptacle.
2. 0 to 125 VDC output. 
3. 12 to 16 ampere output max.
4. 1 volt ripple @ max output.
5. Power supply is to be portable.  Meaning light weight as possible.
6. Must be able to withstand repeated short circuit current on the output. It will be used to energize control circuits for the first time and test them.  Many times short circuits are discovered due to either bad wiring or engineering, usually the wiring.

To ditch a major amount of mass I have chosen a Crydom controller to replace the traditional varaible auto-transformer.

I will feed the output into a rectifier then to some filtering.  This is where I need help. A simple RC filter will require approx. a 10F capacitor to control the ripple at the currents desired.  :o This size capacitor will probably need a "soft start" relay so not to trip the supply circuit breaker, 15 or 20 ampere.  ::) I see regulators on-line, but the current & voltage rating are a fraction of my needs.  I have not investigated using a pie filter ahead of a RC filter. 

Any suggestions would be greatly appreciated.

I am ignoring the input & output protection for now, except using a 10 dollar fuse is out.  That is why the controller is over sized to get more I2t. 


One more overlooked detail is that the input voltage is 120VAC.

What about power factor correction? A large power supply such as this will need power factor correction.

That relay is not a voltage converter. It appears to be a phase controller and would probably not like a non-linear load such as a transformer with a rectifier and huge capacitors on the output.

120V rectified will give 168V so the capacitor will need to be rated to 200V. A 200V 10F capacitor will need to store 0.5*10*2002 = 200kJ. To put this into perspective a 10,000µF 50V capacitor stores 12.5J and has a diameter of 25mm and is 50mm high, your capacitor would be 16000 times that volume.

You need a switched mode power supply and to know what you're doing to do this properly/safely.

This is kind of a very brute force approach to this don't you think?  kW class power supplies are almost always switching.  I am interested to see this evolve for you as 1.5 kW is not typically portable and light weight.

It depends on what you mean by portable? I'm thinking it could fit into something the size of a large briefcase, say 500x300x150mm.

Still you need a lot of experience with power electronics design to do this, its not something for a beginner.


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