Choke Voltage Question

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JMFahey
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Joined: Sun Dec 13, 2009 1:39 pm
Location: Buenos Aires - Argentina

Re: Choke Voltage Question

Post by JMFahey »

Unread post by dorrisant » Wed Aug 30, 2017 11:27 am

the plate is on a doubler at 600+
JMFahey wrote: ↑
Wed Aug 30, 2017 2:54 am

Not exactly, it is a conventional center tapped, bridge rectified supply, basically same as the popular "split supply" used on SS power amps, only one end is grounded instead of center point so instead of +/-300VDC you get +300VDC and +600VDC.
Not to argue, but what is the difference that makes this not a doubler circuit? I just want to understand.
There is no doubling action: you have 500VAC input (250+250 windings in series, working at the same time), you get 700VDC output, the peak value. Standard power supply circuit.

For "voltage doubling" you would need a *single* 250VAC secondary, which half the time feeds a capacitor through one diode to 350V across it, other half feeds another through another diode, again to 350V across it, both are in series so you get 700V end to end.

In this supply you have a four diode bridge rectifier.

That the transformer center tap is also connected to the capacitors center tap is just a convenience to guarantee even voltage splitting/handling; the circuit would behave exactly the same without the center tap, just a single 500VAC winding, a bridge, and 2 series capacitors, only it would need a couple equalizing resistors across them to even voltage sharing better.
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