Best method to build a 30kv DC powersupply.

In summary, flybacks are a cheap and easy way to get on 30kV, but they are dangerous if used without proper precautions.
  • #1
Agnostic
110
0
I was initially going to use just an AC transformer and then some diodes to full way rectify and finally a capacitor on the end to convert to DC. This is probably unrealistic though due to the reverse biasing of the diodes...

Anyone have a good schematic for building s 25kv-35kv DC power supply?
 
Engineering news on Phys.org
  • #2
The boilerplate first response has to be this one:

Why do you want to build a 30 kV power supply? 30 kV is high enough voltage to kill you pretty much instantly unless only extremely small currents are involved.

You will have a hard time with materials and devices which can handle such voltages.

- Warren
 
  • #3
Use a color TV flyback circuit. Oh, and be careful -- is your life insurance policy paid up?

And I echo chroot's question -- what is this for? If it's for a research project and you have good experience working with high voltages, then using a color TV flyback circuit will probably work well. If you're wanting to make a home-brew Jacob's ladder and have no experience yet with high voltages, you're in for a shock.
 
  • #4
My current HV supply for my marx generator which is powering a TEA laser is very non precise on controlling voltage.
 
  • #5
I salvaged the goodies from every tv set that went to garbage. I don't do that any more because I have a drawer full of these suckers.

Flybacks are very easy to hook up, and there are dozens of schematics on the net.

Here is an excellent page with schematics. Flybacks are the cheapest way to get on 30 KV

http://www.kronjaeger.com/hv/

They produce very little current, less than a millamp if I had to guess, that's why they don't pose little or no danger to your life. I was shocked by them dozens of times, and it's quite soothing actually.

But in certain circumstances, a capacitance can develop between the output of the flyback and the surroundings, resulting in an increased current. That's a little dangerous. You can tell if the spark turns from a purple color to a blinding white flash.

Rule of dumb: 1 cm of maximum spark length = 10,000 Volts

Hope that helps.
 
  • #6
Agnostic said:
My current HV supply for my marx generator which is powering a TEA laser is very non precise on controlling voltage.
How much current does the laser require? As waht says, the color TV flybacks are sized for a few mA of electron beam current.

waht said:
They produce very little current, less than a millamp if I had to guess, that's why they don't pose little or no danger to your life. I was shocked by them dozens of times, and it's quite soothing actually.
Holy Zamboni, waht! :eek: You've been hanging around with Danger for too long.
 
  • #7
I work with high voltage (up to 400 KV DC) pretty regularly, and if you don't need much current you may want to consider using a Cockcroft Walton circuit. http://members.tm.net/lapointe/Cockcroft_Walton.htm This will give you an AC voltage that can be filtered to give you a DC voltage. This is going to be pretty expensive, but it should be stable.
 
  • #8
This Cockcroft Walton circuit will give you a full wave rectified voltage that will have an AC component to it. We have a filter on this to give us a stable DC voltage with little to no ripple in it.
 
  • #9
berkeman said:
Holy Zamboni, waht! :eek: You've been hanging around with Danger for too
long.

lol

He's going to be shocked if he sees this.
 
  • #10
Too bad you need 30kV. I once built a HeNe laser using a neon sign transformer (9kV @ 18mA).
 
  • #11
Ideally you want a constant current PSU for driving your Marx. These generally have simple step-up stages to an intermediate voltage and then a switching rectifying unit in an Oil Bath. Look at ALE Technologies or Maxwell, they work the same, the schematics are available for both these systems, but the art is controlling the energy without them catching fire.
 

1. What materials are needed to build a 30kv DC power supply?

To build a 30kv DC power supply, you will need a high voltage transformer, capacitors, diodes, resistors, and a power supply unit. Additionally, you may require other components such as insulation materials, heat sinks, and wiring.

2. How can I ensure safety when building a 30kv DC power supply?

Safety is of utmost importance when working with high voltage. It is crucial to use proper insulation materials, wear protective gear, and work in a dry and well-ventilated area. It is also important to follow the manufacturer's instructions and use caution when handling high voltage components.

3. What is the best method to test a 30kv DC power supply?

Before testing, it is essential to double-check all connections and ensure that all components are properly installed. A multimeter can be used to test the voltage output, and a load resistor can be used to simulate a load on the power supply. It is also recommended to use a variable power supply to slowly increase the voltage and monitor for any issues.

4. Can I build a 30kv DC power supply on my own?

Building a 30kv DC power supply requires a strong understanding of electronics and high voltage components. It also requires careful planning and precise execution to ensure safety and functionality. If you are not experienced in building high voltage circuits, it is recommended to seek assistance from a professional or purchase a pre-made power supply.

5. Are there any precautions I should take when using a 30kv DC power supply?

Yes, there are several precautions you should take when using a 30kv DC power supply. Always wear protective gear, never touch high voltage components with bare hands, and never use the power supply in wet or humid conditions. Additionally, make sure to properly ground the power supply and to have a fire extinguisher nearby in case of emergencies.

Similar threads

  • Electrical Engineering
Replies
10
Views
2K
  • Electrical Engineering
Replies
8
Views
1K
  • Electrical Engineering
Replies
7
Views
3K
  • Electrical Engineering
Replies
4
Views
1K
  • Electrical Engineering
Replies
15
Views
3K
Replies
6
Views
2K
  • Electrical Engineering
Replies
7
Views
843
  • Electrical Engineering
Replies
9
Views
3K
  • Electrical Engineering
Replies
20
Views
1K
  • Electrical Engineering
Replies
25
Views
2K
Back
Top