Voltage Constraint Related Issues

[zzzhhhttt]

Hello, I have some questions while using the Grid2Op environment and would greatly appreciate your assistance.

When running the Grid2Op environment, if topology control actions are used to address issues, could this impact the voltage constraints of the power grid? Additionally, is there a possibility that such actions might cause the voltage to exceed its constraints during operation? Or does Grid2Op's default configuration ensure that all operations are conducted within the voltage constraint limits?

Looking forward to your response, and thank you again!

[BDonnot]

Hello,

Thanks for this really interesting question.

Yes topological modification can modify the voltages. It can even dramatically change the voltages in some buses in some cases.

As of writing, the terminal conditions for an environment are related to isolated loads, generators, grid split into two (or more) independent connected component, the failure of the backend to find a feasible solution to the Kirchhoff Current laws, or if yhe generators cannot meet the demand.

As you see, by default, there is nothing that check the voltages directly.

This is for lots of reasons among which :

• we focused development around flow control, because it was easier to explain to ML researcher what to do and how the grid behave, so easier to get started for l2rpn competitions
• voltages are another type of constraints that we did not modeled yet, so are interactions with some kind of markets, with the maintenance, with the offer / demand, with the system short cut power, complexity for the topological modifications in certain substation, etc. Not everything is currently modeled for convenience reason (it's hard to model everything) but also to make the platform usable relatively quickly without spending first a Master Degree in power grid related issues.
• at start, grid2op used backends that did not properly model the voltages (for example not checking the maximum amount of reactive power that can be absorbed / produced by generators, not changing automatically the tap ratio of some equipments or shuts etc) which made the output voltage with a lesser fidelity than the flows
• all grid2op environment I know of have been calibrated mainly based on current flows and not voltages (for the same reasons mentioned in point 1 above) and it would have been a longer task to also create said environments from a voltage point of view (and as we did not emphasize too much on voltage related issues we did not do it)

That being said, if you would like to advance on this topic, grid2op is fully customizable. And you can easily include voltages constraints in the Backend and trigger some "game over" for certain violations.
Similar things can also be done through a reward that can give "points" to agent depending on how well (according to you) it performs.

A more difficult task would involve modeling properly the action (related to voltages) an Agent can take (for example change the tap ratio of some trafos, the shunts or other elements, add the possibility to give reactive setpoint value to generators etc.) and then to implement it in grid2op framework. Having a proper modeling will take the majority of time and did not had this time yet.

Let us know you are interested in contributing 😊

Hope this help

[zzzhhhttt]

Thanks for your detailed response!!