HarryN
Flashlight Enthusiast
Hi, this application is lighting related, although lighting is only part of the project. This power supply is to drive stepper motors so I can add cnc automation to a lathe (to make flashlights).
I need to obtain or build 2 power supplies:
- 48 VDC x 30 - 40 amps
- 72 VDC x 30 - 40 amps
Incoming power is just standard household 110V 60 hz line power. If it can be made to work internationally that is fine, but not a requirement (home project, not a critical professional level reliability)
Due to the nature of the load, perfect voltage stability is not a requirement, but the primary pull is from drivers that call out a linear PS rather than a switch mode supply.
I had not really thought through what it means to operate in these power ranges vs the normal 10 - 20 watt LED projects I have done, but it gets pretty serious quickly.
The most common approach I am seeing is to start with a toroidal transformer to bring AC to 38 volts, a bridge rectifier to sinusoidal DC, and then Al electrolyte capacitors to smooth out the voltage. Some supplies have methods to dump back EMF from reversing motor loads. (which this also has)
The biggest challenge is specifying the components, especially the capacitors, and that is what I need help with. There are wide ranges of cap pricing with what appear to be small difference in specs. Please check my thinking.
It probably would be easier and cheaper to buy, but I would like to do this as a father + teens summer project if practical.
I need to obtain or build 2 power supplies:
- 48 VDC x 30 - 40 amps
- 72 VDC x 30 - 40 amps
Incoming power is just standard household 110V 60 hz line power. If it can be made to work internationally that is fine, but not a requirement (home project, not a critical professional level reliability)
Due to the nature of the load, perfect voltage stability is not a requirement, but the primary pull is from drivers that call out a linear PS rather than a switch mode supply.
I had not really thought through what it means to operate in these power ranges vs the normal 10 - 20 watt LED projects I have done, but it gets pretty serious quickly.
The most common approach I am seeing is to start with a toroidal transformer to bring AC to 38 volts, a bridge rectifier to sinusoidal DC, and then Al electrolyte capacitors to smooth out the voltage. Some supplies have methods to dump back EMF from reversing motor loads. (which this also has)
The biggest challenge is specifying the components, especially the capacitors, and that is what I need help with. There are wide ranges of cap pricing with what appear to be small difference in specs. Please check my thinking.
It probably would be easier and cheaper to buy, but I would like to do this as a father + teens summer project if practical.
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