Proteus 8 experts?

[DerStrom8]

Hello everyone,

I am looking for someone who is VERY familiar with Proteus 8 and most of its features, including custom component/hierarchy design and simulation, transformer customization, custom simulation settings, and third-party modules. The problems I am facing are quite extensive and would rather not write them all out until I know that there's someone here who might be able to help. So, any takers?

Thanks,
Matt

 

[tvtech]

Hi Matt

I really wish I could help....strictly Eagle here....it's all that I know

Regards,
tvtech

 

[DerStrom8]

Hi Matt

I really wish I could help....strictly Eagle here....it's all that I know

Regards,
tvtech

Yes, I use Eagle for basic circuit and PCB design, but when I need to simulate circuits I opt for Proteus instead.

Cheers,
Matt

 

[Ian Rogers]

I can try and help.... What are you trying to do..... If you need to do advanced simulation, then I can't as I don't have that add on.... I do, however, have 3rd party developer ability!

 

[DerStrom8]

Hi Ian, thanks for the response.

For some reason I chose one of the hardest circuits to simulate: a solid state tesla coil. It's tough to simulate because each "section" relies on another, so it is difficult to simulate the circuit one section at a time like I normally would.

The circuit involves transformers (gate drive transformer, feedback transformer, etc) which seem to always cause convergence issues ("Time step too small) when I run the simulation. I have tried different values for GMIN, RTOL, and all those options in the Simulation settings but still I have no luck. I also placed high value resistors in parallel with capacitors and low value resistors in series with coils, which helped a little bit once but then something else started happening and I ran into even more convergence issues. I have ended up with a "design" that is less like the circuit I will be building in real life and more like a circuit designed just to be simulated.

This SSTC uses an arduino to generate an interrupter signal, which is passed to a UCC27425 dual MOSFET driver with enable. This chip drives the GDT, which then drives two IGBTs. Since the UCC27425 has one inverting and one non-inverting driver, the IGBTs will alternate between each other which is turned on and which is turned off. This causes an oscillation on the primary. The secondary then has a feedback transformer which passes a signal (which is cleaned up by the 7414) back into the 27425 as an input, and the cycle is repeated.

For those who do not have Proteus 8 and want to see the circuit, here is the schematic that I currently have in the simulator:


I included my project file and the hex code for the Arduino in the following ZIP folder.

Again, the main issue I have been having is with convergence, and that is even after applying the simulation settings for better convergence.

Any thoughts of what may be going wrong would be very much appreciated. I've been banging my head for the past couple of days trying to figure this out

Also please note that the UCC27425 is a custom device, and that its child sheet contains the internal schematic.

Regards,
Matt

EDIT: I forgot to mention that I am using a third-party model for the arduino. In order to open my project you will need to download the model files, and add them to your library.

 

[Ian Rogers]

Ooops..... I don't have permissions for AVR... I only have 8051 and all the Pic's..

I have (tried) to get simulation running by using a variable pulse as an interrupter...

Its complaining that a "node #V:Q8:fi1 #branch" is having problems.... But this node isn't in the schematic..

I have found in the past that transformers in general are horrible as well.... They haven't a ground reference and ISIS doesn't like it..

 

[DerStrom8]

Its complaining that a "node #V:Q8:fi1 #branch" is having problems.... But this node isn't in the schematic..

I have found in the past that transformers in general are horrible as well.... They haven't a ground reference and ISIS doesn't like it..

That is another issue I ran into frequently and it has me stumped.

And good point with the lack of ground reference. I had a version a while ago that had them but I think I changed the circuit since then.

What do you mean you don't have permissions for AVR? Do you not have the library?

Thanks for trying it out for me Ian, I'm glad I'm not the only one having the problem.

Regards,
Matt

 

[DerStrom8]

Hello again, Ian--

I decided to connect PRIMARY- and FEEDBACK- on the transformer together to see what happened, and the simulation runs. This means that you're probably right about it not liking the lack of ground reference. However, this bypasses the mains source, so the circuit will not simulate properly when I have this connection made. So I'm still hitting a brick wall at this point, since I can't ground the transformer due to how it's connected. I may have to redesign that portion of the circuit altogether and see if there's a way to make it work.

If you have any more suggestions I would greatly appreciate it.
Regards

 

[Ian Rogers]

When you buy ISIS you buy the microprocessor simulation libraries seperately... I only bought the 8051 and pic bundle...

I can simulate any pic and any 8051 derivative but I cant simulate AVR it would be another £200.00

 

[DerStrom8]

When you buy ISIS you buy the microprocessor simulation libraries seperately... I only bought the 8051 and pic bundle...

I can simulate any pic and any 8051 derivative but I cant simulate AVR it would be another £200.00

Ah, I was afraid of that. Oh well, as you mentioned the interrupter can be simulated any old way, so it shouldn't be a huge issue. Right now I'm having some issues with the low-voltage cutoff section, so I'm redoing that first.

I wish there was a way to bypass the error coming from the transformer not being grounded. It seems pretty stupid if you ask me that a transformer MUST be grounded on one side--there are many circuits in the real world that do not work that way.

 

[Ian Rogers]

I can ask the guy's over the hill.... I know David and Iain... John's a little harder to talk to... I'll email David ( unless you already have done?)

He will ask for the schematic? Are you okay with me passing it on?

 

[DerStrom8]

I can ask the guy's over the hill.... I know David and Iain... John's a little harder to talk to... I'll email David ( unless you already have done?)

He will ask for the schematic? Are you okay with me passing it on?

I'm not sure who any of those people are, to be honest, but by all means! I have updated the schematic so here is the latest. Many thanks for your help, Ian!

 

[Ian Rogers]

Labcenter!!! I only live 30 miles over the hill from them.. They are in Leeds....

I'll send it tomorrow morning.. They won't be there until about 9.00

 

[DerStrom8]

Labcenter!!! I only live 30 miles over the hill from them.. They are in Leeds....

I'll send it tomorrow morning.. They won't be there until about 9.00

Ah, I had no idea you were so close! Sounds great Ian, thank you

 

[DerStrom8]

Well I was able to get around that particular transformer issue by grounding the lower windings on the schematic through 1GΩ resistors, but I still run into the "trouble with node" error with the link that returns "branch not found". I guess that's the main problem at the moment.

 

[Ian Rogers]

He'll probably get back to me soon... I have linked in this thread so he can see whats going on..

 

[DerStrom8]

Hi Ian,

I'm trying another circuit that I found on the internet and I may have found another issue, that could have been causing the problems in my original schematic. If I have the transformer reversed and am accidentally driving the secondary as opposed to driving the primary, does it throw an error? My new circuit uses a center-tapped secondary transformer, but I am driving the transformer from the two coils and attempting to get an output from what is normally the primary side. Is there a way to tell Proteus to switch the secondary and primary? Also, the simple transformer only allows the coupling factor to be between 0 and 1. I thought I had read somewhere that this relates to the turns ratio (N2/N1), which means that the transformer can only be used as a step-down. Was this information correct?

The SPICE transformers seem to be poorly designed and are very difficult to use. Not sure if I'm missing something here or if I simply can't use them the way I want to.

Let me know if you need a copy of the new circuit.

Thanks,
Matt

 

[Ian Rogers]

Primary / secondary... As far as simulation is concerned should make no difference... I will ask how David is getting on, and pose that query...