Creating a Power Supply for a Capacitor Bank

[counterphit]

I am making a large capacitor bank (I guess not that big, but enough to kill you a couple times over) and I need a little help with charging it. I am using 450 volt 1200uf electrolytic capacitors. I have them in two sub banks of 4 wired in parallel, and connected to each other in series. I only want to charge the bank to 800 volts (100 less than it is rated for) and am having a bit of trouble doing this on a budget.

I thought of making a ac transformer and then changing it to dc power, but I do not know of a way to create an acceptible circuit for ac to dc. I have tried to find the circuit diagram online but haven't really found anything.

Another solution I thought of was to create an DC/DC converter and up the voltage to the desired voltage through this. I did find plans for this on the internet, but they seem very complicated, and the problem is that they have it set for a certain output, in my case 10kv, way way too much. I don't know enough about the concept behind the circuit to limit it for my application.

Is there an easy way to limit DC voltage? Because if there is I could just use a neon sign transformer and go from there (those are dc output right?)

If anybody has any suggestions, please let me know, because I am going nuts.

Another thing I thought of was creating some sort of bleed valve for the capcacitors that would dissipate extra voltage when it got to a certain point. this way I could use anything above 800, and not really worry. Any ideas on how to do this?

 

[Divisionbyzer0]

I thought of making a ac transformer and then changing it to dc power, but I do not know of a way to create an acceptible circuit for ac to dc. I have tried to find the circuit diagram online but haven't really found anything.

Would a full bridge rectification circuit, with some filter to smooth the output work? You just have to find diodes which can safely operate at that voltage-- probably not too hard to find, nor too expensive.

 

[ravenprp]

Hello there,

It sounds like you have a challenging project on your hands! First of all, it's important to mention that working with high voltage and capacitors can be extremely dangerous, so please make sure to take all necessary safety precautions and seek professional assistance if needed.

Now, onto your question. There are a few different options you could consider for charging your capacitor bank to 800 volts.

One option is to use a variable power supply that allows you to adjust the output voltage. This can be done with a simple circuit using a transformer, rectifier, and voltage regulator. You can find many tutorials and diagrams online for building a variable power supply, and it can be adjusted to output the exact voltage you need.

Another option is to use a step-up DC/DC converter, as you mentioned. These can be more complicated to build, but there are also pre-made modules available that can be adjusted to output the desired voltage. You may need to do some research and experimentation to find the right one for your project.

Regarding your idea of using a neon sign transformer, these do output DC voltage, but they may not be suitable for charging your capacitor bank as they typically have a lower current output. It's important to make sure the power source you use can handle the current needed to charge your capacitors safely.

As for your idea of a "bleed valve" for the capacitors, this is called a bleeder resistor and it is a common safety feature in capacitor banks. A bleeder resistor is essentially a high-value resistor connected across the capacitor terminals, which allows any excess voltage to be safely discharged. The exact value of the resistor will depend on the capacitance of your bank and the desired discharge time. Again, it's important to consult with a professional or do thorough research before implementing this in your project.

I hope this gives you some ideas for how to proceed with your project. Remember to always prioritize safety and seek professional assistance if needed. Good luck!