Reactive power control
I have a system with a generator conected to transformer and this connected to a swing bus and when I apply a voltage step of 2%, I want the reactive power to go from -12 Mvar to 8 Mvar. But it only increases from -12 Mvar to -3 Mvar.
Generators control voltage. They will put out whatever Mvar is needed to control a voltage. Sounds like you want to control Mvar and voltage independently, but they are dependent on eachother..