Ceska verze

3-phase high voltage supply with 6 MOTs

    I wanted to test how the discharegs will behave with the DC current. So I built the three-phase high-voltage high-power PSU. For transformation I used a total of 6 MOTs (transformers from microwave ovens). At each phase there's one pair of MOTs connected with both primary and secondary in parallel. The resulting pairs are then connected to the star configuration. Current limiting is provided by 9 capacitors from microwaves (capacity around 1uF), 3 in parallel in each phase. Output voltage is three-phase bridge rectified. I needed 6 high-voltage diodes. Each of these is created by combining 12-BY255 (1300V 3A) and therefore withstand voltage 15.6 kV and current of 3A. Voltage of this source with no load is about 6kV, Short-circuit current to 3.5 A. When shorted, it draws 3x 11A from three phases of 230V~, so it is is 7.6 kVA. Supply can work with the 6-capacitors (one from each branch removed) - MOTs then produce much less heat, but the current is smaller. In the supply I used MOTs 1,3,4,5,6 a 8 from the table of my MOTs .

    Arcs from the three-phase supply are characteristic by its sound, in which instead of folders 50Hz and 100Hz prevails combined frequency of 150Hz and 300Hz. Three-phase rectified current never passes through the zero point, and therefore discharges don't extinguish so easily. See the photos and videos below :).

     Warning! Output voltage of transformers from microwave oven is about 2100 Vac. This voltage is absolutely deadly! Capacitors can remain charged even after shutdown. Everything you do at your own risk. Author takes no responsibility for any injury, deaths or property damage.

The schematic of the three-phase high voltage supply with 6 MOTs
The schematic of the three-phase high voltage supply with 6 MOTs

entire 3-phase power supply with six MOTs and nine MO capacitors.
entire 3-phase power supply with six MOTs and nine MO capacitors.

Sparks from the 6 MOT high voltage supply :)
Sparks from the 6 MOT high voltage supply :)




occasionally the discharge was too big for the picture
occasionally the discharge was too big for the picture :)

Vertical arc
Vertical arc

just disappearing discharge
just disappearing discharge

























plasma after discharge disappeared
plasma after discharge disappeared

   short current measurement
short current measurement

100pcs of diode BY255 (1300V 3A).
100pcs of diode BY255 (1300V 3A). I used 72 of them

high voltage electric candle :)
high voltage electric candle :)

"three-phase" wall outlet
"three-phase" wall outlet

circuit breakers
circuit breakers


Video - discharges with 6 capacitors (3x2)


Video - now discharges with 9 capacitors (3x3)


home