How can I change the value of load during TDS?

[MuaYoi]

Hello! I'm going to run a TDS where one load increases from 250MW to 350MW at a certain moment. I have read the documentation of model "Alter", but I am confused by the sentence "To apply a PQ load change, according to [PQ], one needs to set the load model to constant power and alter Ppf and Qpf." I do not find Ppf and Qpf in the variables of model PQ, thus I don't know which value I should modify.
Would you mind giving me an example code or some suggestions?

[Albizzian]

Ppf and Qpf are config paraments of PQ used in running simulations, you can check and adjust the values by using code andes misc --edit-config in command line.
For Alter, you can use the code as follows, it adjusts Ppf and Qpf on the fly:
ss.add('Alter',dict(model='PQ',dev='PQ_1', src='Ppf',t=1.0,method='+',amount=1))
andes.run('*.xlsx', routine='tds',tf=15, config_option["PQ.p2p=1.0","PQ.p2z=0.0","PQ.q2q=1.0","PQ.q2z=0.0"])
Hope this helps.

[MuaYoi]

Thank you very much, Albizzian!
Could you please provide the xlsx file and a picture showing the generator speed curve for me to debug? Maybe I made some mistakes in my xlsx file.

[Albizzian]

You're welcome!
Here are the file and code with the figure of omega.
ieee39_full.xlsx
Alter_PQ.pdf

[MuaYoi]

Hi Albizzian!
I am surprised that your file worked very well. The difference between my file and yours is that I add a sheet named "ZIP". Should I use ZIP load to replace the PQ load? I think the reason alter of PQ didn't work is because I added the ZIP load but why?

[Albizzian]

Hi MuaYoi:
I agree with you that the reason might be adding the ZIP model. But I am not familiar with ZIP model, so I can't analyse your bug in detail. I recommend you read the help documentation https://docs.andes.app/en/latest/groupdoc/DynLoad.html?highlight=ZIP#zip, and maybe it helps.
Best Regards

[MuaYoi]

Hi Albizzian!
I think Wang Jinning's view is correct, you can check his comments on this topic.
Thank you for your help. I have adopted your answer and wish you a happy life!

[jinningwang]

After reading the ZIP and PQ documentation, my opinion is when ZIP load is in effect, the linked PQ load will be disabled if any.
In this case, I feel altering Ppf and Qpf should still work but the output power should take ZIP parameters into account.
If ZIP load is not linked with any PQ load, then they can be manipulated and no interaction happened between them.

I am not familiar with ZIP load, but welcome further discussion. Also, posting a figure and describe what happened and what you expect can be more informative.

[MuaYoi]

Thanks for response, Wang. I agree with your opinion. Even though I modified kpp and kqp to 100, kpi, kpz, kqi, kqz to 0, generators' omegas still didn't change. It seems that Ppf and Qpf will not be taken into account after ZIP model linkes with PQ load. If given the opportunity, I will make further attempts and share the results with everyone.

[jinningwang]

No problem. You are encouraged to share a minimal code and results fig in the future.