Kapanadze Cousin - DALLY FREE ENERGY

[verpies]

But concerning the low inductance, well that's the design of this toroid i guess.  Or should we deviate from this and use much more inductance?

I think we we should eliminate the possibility mentioned in the P.S. of this message by measuring T1's winding with an inductance meter.

If the inductance meter shows much more than 50nH then this will be the sign that the core becomes saturated very soon after the MOSFET starts conducting...and we just can't see it.

[itsu]

I think we we should eliminate the possibility mentioned in the P.S. of this message by measuring T1's winding with an inductance meter.

Ok, i just tried to measure the inductance with my Voltcraft LCR-9063 LCR-multimeter which has a spec. of 0.1 µH à 20 H at 250Hz, and it show -0.016mH (16uH), but it shows this for both primary (6 turns) and secondary (12 turns). 
Also the minus sign (-) in front of the value does not make me happy, so i don't think this value can be trusted.

Regards Itsu

[verpies]

...it shows -0.016mH (16uH), but it shows this for both primary (6 turns) and secondary (12 turns). 

Yes, the inductance of the 12-turn winding should be 4 times higher than the inductance of the 6-turn winding (inductance is proportional to the 2^nd power of the turn count, see here )
It looks like the meter is measuring its own internal inductance (including test leads) or picking up some EMI

[d3x0r]

The usual ways: overcurrent when closed or overvoltage when opened.

If you think of using these Solid State Relays in Dally's circuit then forget it.  They are too slow.
I'd be lucky if they can make and break in 1ms (1kHz).

Actually it was working with the very narrow pulses from the TL494 at whole range of frequency.  It was working, until I attached high power (150V) directly;  It arced once, then it stopped transferring.  on the 150V I have a 40uf cap... would really find it hard that it would generate a killer surge to the relay, but yes it apparently was.  that's how I blew up my NTE2319 before too, attaching the high power live.

[verpies]

100kHz switching frequency is amazing for a Solid State Relay (SSR) !
Maybe you exceeded its maximum voltage rating when you connected that 150V supply. 

What was the load connected to this SSR then ? Were any flyback diodes or snubbers connected across the load or the SSR?
If the load was inductive when the relay opened, the inductor easily could have generated 10kV across that SSR.