Set fixVoltageTargets=false for contingency computation

[SylvestreSakti]

Please check if the PR fulfills these requirements

• 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)
• A PR or issue has been opened in all impacted repositories (if any)

Does this PR already have an issue describing the problem?
No

What kind of change does this PR introduce?
In security analysis and sensitivity analysis, when fixVoltageTargets is set at true, we do not want to fix the voltage targets in contingency cases. Indeed, there are currently two drawbacks for this :

• Performance issue since the admittance system is computed again for each contingency
• Exception thrown because the admittance system was not correctly computed for disabled elements

What is the current behavior?
In security analys and sensitivity analysis, if fixVoltageTargets is set at true, there is a high chance of getting an exception of unequal number of equations and variables in the admittance system matrix when computing contingencies.

What is the new behavior (if this is a feature change)?
In security analys and sensitivity analysis, if fixVoltageTargets is set at true, voltage target check is done only for pre-contingency status

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

• Yes
• No

[sonarqubecloud]

Quality Gate failed

Failed conditions
87.5% Coverage on New Code (required ≥ 90%)

See analysis details on SonarQube Cloud