Is this Charger/Pulse schematic fundamentally correct?

[nsled]

As attached, Is this fundamentally correct?

 I have everything short the power supply and voltmeter.

[MRMILSTAR]

The voltage multiplier is going to need a HV power supply with a much higher frequency than 60 Hz to generate any significant continuous voltage. It will probably have to be at least 10 Khz. Since your capacitor has a maximum rating of 5 KV, it would be easier to just connect 2 MOTs in series with a full wave bridge rectifier made from microwave oven diodes. This would give you a maximum of a little over 5 KV peak DC. I would just dispense with the voltage multiplier.

That relay may cause problems due to contact welding due to the extremely high current. I use a spark gap switch to avoid that problem. You also need a way to disconnect the charging circuit from the capacitor before firing.

This size of capacitor is suitable for can crushing, disc launching, and wire exploding. You would only get minor coin shrinkage with this amount of energy.

I have attached a schematic of my pulsed power generator.

[nsled]

Oh ok, thankyou. As I process this ..

Would it be more suitable and simpler to buy a laser flyback like the following https://www.aliexpress.com/item/32775103121.html?spm=a2g0o.order_list.order_list_main.5.21ef1802oD81aU

Its rated output is approx. 100:1 so maybe just hook a 48v scooter battery up to that, and bypass the multiplier that way?

So, 48v battery -> 100:1 flyback -> relay -> 5KV capacitor

Also isn't the relay isolating the charging circuit in the way I've shown wired? that was the intent. I should relocate the divider circuit to be the multiplier side of the relay too.

[MRMILSTAR]

I see now that your relay will isolate the charging circuit. At initial glance I thought it was your firing relay. You don't indicate how you are going to trigger this capacitor. Maybe you are just going to use a hot stick and some wire.

You can use a DC flyback transformer to charge the capacitor although the charging period may be long. I would use that and get rid of the voltage multiplier.

[nsled]

It's a double throw relay, it isolates and fires it.

Ok I just ordered a flyback, the way I see it the simpler the safer. Would the flyback also need to be isolated before firing? Maybe with protection diode?

I don't know if these require a driver or its built in. I assume not, so would a PWM dimmer be suitable? Something like this  https://www.aliexpress.com/item/1005005248196976.html?spm=a2g0o.order_list.order_list_main.5.770a1802S4ajWS

[MRMILSTAR]

I use a ZVS circuit to drive the flybacks on my voltage multiplier and Marx generator.

I would isolate EVERYTHING from the capacitor and load when firing. Don't rely on a diode for safety or protection. You need mechanical switches. If you don't it could damage the charging circuitry including the flyback. I've blown 2 sets of full-wave bridge diodes because I forgot to disconnect the charging circuitry before discharging the capacitor. I now use a checklist. I also disconnect the charging circuitry from the wall power before firing. You don't want to allow for the possibility of that capacitor discharge getting back into your wall power. That could destroy every electronic item in your house which is plugged into the wall power. I use three 10-foot lanyards made of nylon to remotely activate the switches on my machine. You don't want to allow any possibility of that capacitor discharge coming back at you.

Here is the sequence that I use on my machine:

1. Charge capacitor
2. Disconnect charging circuitry from capacitor and load
3. Disconnect charging circuitry from wall power
4. Discharge capacitor
5. Dump remaining capacitor charge into dissipation resistors (check remaining charge with voltmeter)
6. Use hot stick to insure capacitor is fully discharged
7. Connect safety wire between capacitor terminals
8. You can now safely handle the load and other wiring

Its best to have a checklist to insure that you don't forget any of the operations. This may seem complicated but its absolutely necessary for these high-energy capacitors. They will kill you instantly if you are careless. My 220-pound capacitor can blow your arm off if its fully charged (24,000 joules).

If you aren't aware of it I have an extensive posting on my pulsed power generator in this group.

[davekni]

I use a ZVS circuit to drive the flybacks on my voltage multiplier and Marx generator.

I would isolate EVERYTHING from the capacitor and load when firing.

Not needing fast charging, I use a 1meg resistor (20S2P of 100K resistors) between my 20kV 14uF pulse cap and charging circuit.  That has worked for 21 years and over 1500 shots of coin shrinking.

[nsled]

OK, thanks guys this is where I'm sitting at the moment.

i have some concern about only 48v into a 150v rated transformer but I'll wired it up and check output.

It would be really convenient not to have to isolate the capacitor as I have this specific scenario playing out in my head with contact being made between two foil sheets [bang/sparks] then auto recharge. My Ross relays I have 240v solenoids thus won't work with the 48v battery.

So resistors in series with the capacitor? What values and charge time are likely?