Add start-up & shut-down variables

[Cerberus22]

Related issues

There is no related issue.

Changes introduces:

Variables were added to the model describing start-up and shut-down behavior of generators, if their unit commitment method is set to 3bin-., where . can be replaced with anything. Additionally, constraints were added to ensure the variables are correctly related to the existing model. Finally, a test case was added that will demonstrate all the constraints using the start-up & shut-down variables that will be added in later pull requests.

Checklist

• I am following the contributing guidelines
• Tests are passing
• Lint workflow is passing
• Docs were updated and workflow is passing

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 98.38%. Comparing base (b56e625) to head (be80dc3).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1318      +/-   ##
==========================================
+ Coverage   98.31%   98.38%   +0.06%     
==========================================
  Files          35       36       +1     
  Lines        1306     1361      +55     
==========================================
+ Hits         1284     1339      +55     
  Misses         22       22              

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[abelsiqueira]

Thanks for the PR. I have some preliminary comments to complement the e-mail discussion.

I've enabled the workflows to run so the tests actually run. The benchmark can't run because it's from a fork, so you have to manually look into the documentation for instructions on how to run the benchmarks locally, and then paste the results here.

I haven't checked the content in details, and I won't evaluate the math behind it. Some comments on the rest:

• The file name 3bin is not clear. It would be better to be explicit on what is supposed to be.
• From recent experiences, I think it is better to split the 3bin file into two or three files (e.g., for simple and compact). Maybe create a folder for organisation, if you think it's necessary.
• From recent experiences, we are trying to use Common Table Expressions (CTEs) in the query to improve readability. We don't have many examples, and not all queries require it, so maybe this is not necessary here. I leave the comment so we remember to check later.
• Since you created a new case study, update test-case-studies with it. Otherwise, the new case study doesn't seem to be used anywhere.
• You need documentation, at least for the formulation.
• I don't get what the argument is 3bin-* where * is anything. Why is it left so broad?
• It's better to first create the new case study in a separate PR with the test update. Makes it easier for reviewers.

Thanks!

[urosgluscevic]

@abelsiqueira Thank you for the comment! I have split the 3bin.jl file into 3 files as you suggested, and given them clearer names. I have also added our case study to test-case-studies.

As for the question regarding the argument being named 3bin-*, we did this because we will be adding many different unit_commitment_methods, representing different levels of detail which can be used to model generator start-ups and shut-downs, but the constraints in this PR will be used in all of those levels of detail.

I also had a question about the benchmarks - should we change anything in the benchmarks, since we have added new variables and constraints, which only get created when the new 3bin-* argument is used?

Also, regarding your last point, is this something we should keep in mind for future PRs, or should we remove the test case from this PR?

Finally, I will hopefully push the changes tomorrow, after adding the documentation! Thank you very much for your help!