[SOLVED] High-power-capacitance-voltage-doubler topology

[d123]

Re: High power capacitave voltage doubler topology

Hi,

I think, if I've understood, that what you may want to look into is PFC about the diode propagating to the grid.

A typical start-up inrush current-limiting circuit is a series resistor in parallel with a MOSFET. The resistor deals with the initial spike, then the lower resistance MOSFET is used as the path from source to load (supply to Dickson/Dickinson charge pump). Sorry if I'm missing the point about anything.

 

[FvM]

Re: High power capacitave voltage doubler topology

O.K. discharge current is smaller that I expected, respectively there's no huge current peak propagated to the grid. I notice that you have an unrealistic high switch resistance. Should be milliohm in case of a mechanical switch.

Anyway, if you expect that the about 30 A peak current is tolerated by your fuses, it may work.

By the way, why are you starting with closed discharge switch. You have also more power dissipation than necessary in the coil by holding the switch closed after discharge.

 

[Zak28]

Re: High power capacitave voltage doubler topology

Hi,
...with a MOSFET...

I am not going to purchase mosfets for this circuit, especially with all the high voltage in it.

O.K. discharge current is smaller that I expected, respectively there's no huge current peak propagated to the grid...

I am considering a series inductor between multiplier stage capacitor and ac mains to limit current to ~16amps, since my breakers are 20amp rated. I am considering winding my own inductor since I could not find anything applicable on retailer sites and also I have a few ferrite rods, but I probably need a C or E core with a bobbin.

I modified load resistance to reflect real value, let me know if current is low enough to not use current limiting inductor.
View attachment pulser2.zip

 

[FvM]

Re: High power capacitave voltage doubler topology

A useful 60 Hz choke to limit the input current will better use a laminated iron core than ferrite, achieve higher permeability and saturation flux.

 

[Zak28]

Re: High power capacitave voltage doubler topology

...a laminated iron core...

Ferrite is way better because at 16amps or more it wont become really hot unlike laminated iron.

 

[KlausST]

Re: High power capacitave voltage doubler topology

Hi,

Iron or ferrite is more a question of frequency and not of current.

Klaus

 

[Zak28]

Re: High power capacitave voltage doubler topology

Hi,

Iron or ferrite is more a question of frequency and not of current.

Klaus

I just dont want excess heating from eddy losses.

 

[BradtheRad]

Re: High power capacitave voltage doubler topology

This simulation is based on your schematic, then adding a resistor and inductor at the power source. These are not necessarily optimum values, nevertheless the aim is to portray an easy method to correct power factor error. Also to limit Ampere level during power-up current surge. Notice the output capacitor is charged almost to 300V at the end of 1 second.

 

[FvM]

Re: High power capacitave voltage doubler topology

Ferrite is way better because at 16amps or more it wont become really hot unlike laminated iron.

I just dont want excess heating from eddy losses.

Sounds like you have only a remote idea about choke operation principle and design methods but are nevertheless resistant to advice. Not the best foundation when seeking for help.