powsybl-open-loadflow [WIP] Avoid angle divergence with HVDC AC emulation and PMax

[WIP] Avoid angle divergence with HVDC AC emulation and PMax

Open vidaldid-rte opened this issue 11 months ago • 1 comments

Please check if the PR fulfills these requirements

[X] The commit message follows our guidelines
[ ] Tests for the changes have been added (for bug fixes / features)
[ ] Docs have been added / updated (for bug fixes / features)

Does this PR already have an issue describing the problem? Users report convergence problems with HVDC and AC emulation and PMax

What kind of change does this PR introduce? When angle difference at HVDC bounds is larger than the operational range of the HVDC (ie range in which P grows with angle difference), the derivative for the AC emulation term does not return 0 for dp/dphi but the slope between bounded teta and angle value for which P = 0/

What is the current behavior? Possible divergence if NR initialized with angle values out of the HVDC operational range.

What is the new behavior (if this is a feature change)? Better convergence. However, if a network convergence state is far outside of the operational range of an HVDC in AC eumlation mode, sensitivity analysis may return incorrect value (because dp/dphi does not return null)

Does this PR introduce a breaking change or deprecate an API?