what is the most efficient way to pull voltage off a large dc bus(230-400) to power a control board
230-400 volts dc? yikes What's the power board requirements? You do know that this source could kill you?
I think people would get a better response if they explained a bit more.
Forgive me for being vague. I am very aware of the danger involved with working with this level of voltage. I intend to run whatever designs i have on a spice program before actually building the componenets. I am just trying to go from this large bus voltage down to about 12-13 volts that i can then run through another voltage regulator setup to get my final specific voltage and current. The difficult transistion for me is the initial stepdown. i have looked at isoated flyback switching device or a power supply of some sort. Just trying to be efficient with e power thta i have seeing as how in EV's efficeiency is everything due to the limited energy density of batteries. Another option i have though of is having a second battery setup to run the controller and secondary components, much like a car battery.
What current do you need?
Loads of off the shelf PSUs available .. linear of switched mode. Just make sure is it well fused as well as being fed through a breaker.
Is this for an electric vehicle? You can use a computer power supply, these take line voltage and rectify it to dc, so you can just remove the bridge rectifier and input power from the line side filter caps, just make sure the supply you use is suitable for your voltage, many will operate from 89 ac volts to 380 ac. Oh also, you want to remove any pfc circuits as well, as they will not be needed.
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