Low frequency circuits

[DesmondTan]

Hi , i was thinking of home-brewing a plasma spark project using household input voltage of 230 Vac, 16 amp and 50/60Hz.
For a start, i would like to step down the house whole voltage(230 Vac, 16 amp and 50/60Hz) to DC using a rectifier and than increase the frequency from 50/60Hz sine wave to 10KHz ~ 30KHz square wave using mosfet inverter. After which i will use a HF voltage transformer to pump up the voltage to several thousand volts.
Is it possible to achieve a plasma spark using a rectifier, mosfet inverter and a HF transformer? Do i need any capacitors?
Many Thanks.

 

[WimRFP]

It is definitely possible, some kW is more then enough to make a very spectacular gas discharge, but you really need to know what you are doing (High Voltage Engineering and Safety aspects).

If this is your first power poject, look for something else, unless you have somebody near you that can guide you during the design and construction process. You may pay an error with severe injury or even with your life.

Regarding rectification, it will not "step down" the voltage. If you use a bridge rectifier you will get a no load voltage very likely around 330V (without galvanic isolation). This 330V will very likely be fed to a full bridge circuit (so that you still can use MOSFET instead of IGBT). As arcs show negative impedance/resistance, you need a current limiting scheme (similar as used in a "ballast" for fluorescent lighting).

 

[mtwieg]

You don't need any specific DC voltage to generate an arc. It just determines what kind of turns ratio you need on your transformer to get the desired output voltage.

I've built some very high power musical tesla coils and singing arcs in the past, and I recommend you start with a simple and low power method, especially if you are not experienced in power electronics. A flyback arc generator is a good starting point. 4hv.org is a good place for general info on HV projects like this, also check out the HV wiki.

High voltage is incredibly dangerous and a single mistake can kill. You should never conduct high energy/high voltage experiments alone (get a CPR buddy).

 

[DesmondTan]

Hi buddies, many thanks for your concerns on personal safety, appreciated that.
I hope to gather enough info on the subject and than look for a power electronic chap to provide assistance.
I will start a small project first. Thanks

- - - Updated - - -

Hi buddies, many thanks for your concerns on personal safety, appreciated that.
I hope to gather enough info on the subject and than look for a power electronic chap to provide assistance.
I will start a small project first. Thanks