Hvdc AC emulation: support of -Pmax/Pmax

[annetill]

Describe the current behavior

For the moment, we support a bounded flow on an hvdc line in AC emulation through the equation system in all AC calculations. For DC load flow and DC security analyses, the -Pmax/Pmax saturation is not supported. Note that for DC sensitivity analyses, AC emulation is not supported at all.

• In AC calculations, if the hvdc is saturated, it is not able to go back to linear equation mode even if it should.
• In DC calculations, saturation is not supported at all.

Describe the expected behavior

• AC calculations : switch from linear mode to saturation and switch from saturation to linear mode must be supported.
• DC load flow and DC security analysis: at least a switch from linear mode to saturation must be supported.
• DC sensitivity analysis: no support for the moment.
  The solution could be an outer loop for AC and DC runs. In order to have a light implémentation, the AC emulation equations must be 1) active in case of linear mode 2) inactive in the equation system in case of saturation mode but used to monitor when the hvdc could go back to linear mode.

Describe the motivation

No response

Extra Information

No response

[vidaldid-rte]

If PMAX/PMIN is implemented in DC, care should be taken about the interactions with the woodbury engine for sensitivity and/or security analysis. An HVDC with saturation is no longer linear.