Hi there. I need help with my simulation. The schematic is attached.

I change the value of R3, from 0% to 100%, to change the signal frequency. I want to see the output signal from every stage in all frequency, so I know the range of frequency which gives output good signal.

The problem is, I always get a convergence error when the R3 is 10% to 50%. Whereas, I want my induction heater operate at R3 15%-50% (freq. 20kHz -50kHz). It can only run for about 0.5 ms.

My question is:
1. What make the circuit error at those value of R3?
2. At those value of R3, the circuit can run for about 0.5 ms. It gives enough signal form on the oscilloscop. Is the signal form that the oscilloscope obtained enough for representing the circuit behavior?

Thanks alot guys. I hope some one can help me resolve this.

 

I don't have multisim or the tl494 for ltspice so only a guess that the dead time is to long for the higher frequency?

 

I don't have multisim or the tl494 for ltspice so only a guess that the dead time is to long for the higher frequency?

Thanks ronv for your response. I wanna ask, is it okay to let the last output (the 20:1 transformer) floating (not connected to anything, such as load or ground) as shown in the schematic?

Sorry, I still newbie in electronic. I'm in mechanical engineering.

 

Hmm. The simulation may not like it. You could put a small load on it and add say a 10 meg to ground so it has a ground reference.

 

Hmm. The simulation may not like it. You could put a small load on it and add say a 10 meg to ground so it has a ground reference.

All right, thanks alot ronv, now, i got no error.