Hi Community,


I am using the compiler of OpenModelica on a power system testcase and I observe that some variables and equations are added to my system.

They correspond to the derivatives of some of the algebraic variables:


//algVars (30)
//----------------------
type: algVars (30) index: 6: $DER.test.line.terminal1.pin[1].v (no alias) valueType: real initial:      arrCref:$DER.test.line.terminal1.pin.v index:(7) [3]
type: algVars (30) index: 7: $DER.test.line.terminal1.pin[2].v (no alias) valueType: real initial:     no arrCref index:(8) [3]
type: algVars (30) index: 8: $DER.test.line.terminal1.pin[3].v (no alias) valueType: real initial:     no arrCref index:(9) [3]

...

type: algVars (30) index: 27: test.line.terminal1.pin[1].v (no alias) valueType: real initial: test.line.V1A0     arrCref:test.line.terminal1.pin.v index:(28) [3]
type: algVars (30) index: 28: test.line.terminal1.pin[2].v (no alias) valueType: real initial: test.line.V1B0    no arrCref index:(29) [3]
type: algVars (30) index: 29: test.line.terminal1.pin[3].v (no alias) valueType: real initial: test.line.V1C0    no arrCref index:(30) [3]


What is the condition for those variables to be generated?


Thank you and Best regards