Hi..
I have build a totem pole Gan boost pfc on LTspice. The model seems to correct, as there is no error popping up while the simulation but the simulation speed is very slow. It takes about 3hours for 3ms.. never completes the simulation.. simulation runs with respect to pico or nanoseconds speed range. As I am new to the tool, someone please check my circuit and let me know how can I speed up my simulation speed. I have attached the circuit here!

 

Couldn't find symbols:
TPH3205
LM5113_trans
SFH6136

 

I have attached the .lib files along with the circuit model ...you can auto generate the symbols from those .lib file.
Thanks

 

You want to be helped, but in addition you load potential assistants. I wanted to help you and could help you (I have a great experience in using the program LTspice). But now I have lost the desire to help you.

 

Hi Bordodynov
Sorry you have mistaken me.. even I didnot find the actual symbols of lm5113, SFH6136 and TPH3205 on LTspice tool. I have auto generated them from the .lib files only. As I am new to this tool I couldnot draw symbols of the same. I will attach the auto generated symbols here. Your suggestions will be a great help to me.

 

My opinion: the electronic scheme will not work as you intended. I slightly improved the driver model. It can still be slightly improved, but it takes time.

 

Hi..
Thankyou very much for your time..that was really a big help to me..I will check on the LTC4444 driver. But the gate pulses for the higher side GaN G_H is more of spikes, I doubt on the gate drive transformer circuit, which I have edited further but couldn't fix. Please review on the same.
the simulation speed is quite good now in the beginning but it get stuck after 15% for hours. Please help.

Thanks

 

Simple model transistor.

 

Hi.. Thank you for the simple_transistor model.The simulation speed is really good now!! I am facing an issue with the driver LTC4444 as you mentioned earlier. I have followed the same circuit as in the LTC4444 datasheet and application note. Please help me out in fixing the error with LTC4444.

Thank you

 

See

 

I have taken out of scheme spare. Has Lowered the frequency to possible was quickly look at occurring processes.

 

Hi .. Thank you very much for your valuable time again!! Yes since the low frequency FETS can be driven from normal transistor driver circuits, I go with the improvements that you have done by removing the LTC4444 driver. But I see that my boost output is not achieved. I am getting 35V DC but I expect around 400V across the load. I have changed the resistance value RL=247ohms @ 650W.

 

Also please check this circuit where I have used normal driver circuit for sync_rec FETs . There is an error popping w.r.t the Q4 npn transistor module U9.

Thanks

 

I did not try to understand with thought, mortgaged your schemes. I have simply denuded the problems. I have noticed that upper conclusion of the driver is not used for governing gate. So I have done this usual driver with standard parameter. If your scheme does not work, that this not my blame.

 

Optocoupler not work (symbol+model is bad?). I do not think that you will manage such scheme to raise the voltage. I this not to manage.

 

Is the issue with the opto? May I get an opto coupler LT spice model from you? Or any link can you suggest me for finding the same?
Sorry if I am troubling you more. I have to submit this simulation as my project in college in other 2days. So kindly help me out.

 

I tried to revive your circuit. I found that the optocoupler does not function. Then I replaced it with a standard transistor optocoupler, which caused this part of the circuit to function. I found that the synchronous rectifier chip is not used as intended. Note that the new, cascode transistors have built-in diodes!

 

I tried to revive your circuit. I found that the optocoupler does not function. Then I replaced it with a standard transistor optocoupler, which caused this part of the circuit to function. I found that the synchronous rectifier chip is not used as intended. Note that the new, cascode transistors have built-in diodes!

Hi.. thanks again for your great suggestions and time! May I get the changed schematic file in which you have replaced the standard transistor opto? And yeah myself too still working with the circuit to get the expected results. Please let me know if any other changes I need to make after changing the opto too..

Thank you

 

Hi .. according to your suggestion I replaced the opto circuit with iso-transistor. Now there are no errors. But both the low frequency MOSFETs gate pulses look distorted with lot of spike. I did some workarounds but could not fix it. Please sir help me on the same.

Thank you.

 

I came to the conclusion that you set yourself an impossible task. In your circuit again, errors. I concluded that there was insufficient qualification. Why do not you use standard solutions? I suspect that the idea of this scheme is not correct. I wanted to help, but did not solve your problem.