So I just always understood principle of full wave Cockroft Walton multiplier to be basically running two halfwave multipliers on opposite sides of a center-tap so the 180° phase difference develops a composite output with low ripple and better load regulation?
Anyhow HP suggested I just use three stage full wave CW multiplier cuz I'm having problems with xfmr voltage stress using just doubler. She sent me schematic of circuit (like attached pic). She said it doesn't need center tap and that performance is not degraded without it (which is good cuz most HV winding aren't tapped).
Well the more I thought abt it the more convinced I got that she had to be mistaken so I modeled it in Ltspice and it totally agrees with what HP is saying!
So K1 is just 1:1 transformer that I added so grounded tap vs floating tap operation can be easily compared.
Now I'm feeling totally dumber than usual cuz I can't understand how grounded tap and non-grounded tap operation are identical! There's just no difference in output current, voltage, ripple, buildup time and like that! And input current waveshape, _inrush_ magnitude and duration are same also
So I get that the circuit somehow sees a totally solid virtual midpoint when running w/o center-tap (which explains why output is Pk input * number of stages (instead usual CW factor of 2*pk input * number of stages) but I just can't get my mind around how!
So to put fine point on it here's questions:
◊How can grounded center-tap operation be exactly the same as when it's not connected?
◊Why isn't there a single solitary mention or example of non center-tapped operation anywhere on the net (I've looked for hours!)
HP isn't available to ask right now and anyhow maybe hearing explanation in other words will help clear _block_ Anyhow I hope it's just mental block and not plain stupidity
Here's schematic: Also I've attached .asc file so for standard connection just ground node "T"
So tnx in advance for helping me recapture my sanity!
PS R1 and R3 are just to keep Ltspice happy!
Anyhow HP suggested I just use three stage full wave CW multiplier cuz I'm having problems with xfmr voltage stress using just doubler. She sent me schematic of circuit (like attached pic). She said it doesn't need center tap and that performance is not degraded without it (which is good cuz most HV winding aren't tapped).
Well the more I thought abt it the more convinced I got that she had to be mistaken so I modeled it in Ltspice and it totally agrees with what HP is saying!
So K1 is just 1:1 transformer that I added so grounded tap vs floating tap operation can be easily compared.
Now I'm feeling totally dumber than usual cuz I can't understand how grounded tap and non-grounded tap operation are identical! There's just no difference in output current, voltage, ripple, buildup time and like that! And input current waveshape, _inrush_ magnitude and duration are same also
So I get that the circuit somehow sees a totally solid virtual midpoint when running w/o center-tap (which explains why output is Pk input * number of stages (instead usual CW factor of 2*pk input * number of stages) but I just can't get my mind around how!
So to put fine point on it here's questions:
◊How can grounded center-tap operation be exactly the same as when it's not connected?
◊Why isn't there a single solitary mention or example of non center-tapped operation anywhere on the net (I've looked for hours!)
HP isn't available to ask right now and anyhow maybe hearing explanation in other words will help clear _block_ Anyhow I hope it's just mental block and not plain stupidity
Here's schematic: Also I've attached .asc file so for standard connection just ground node "T"
So tnx in advance for helping me recapture my sanity!
PS R1 and R3 are just to keep Ltspice happy!
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