First time here? We are a friendly community of Power Systems Engineers. Check out the FAQ!
You have entered variable name REGCA1, which is not defined in the code, instead of string 'REGCA1'.
However, the voltage reference shall be changed with api change_vref
!
The voltage setpoint is defined in REECA1 and not in REGCA1!
Do you really want to change the setpoint to 115 pu?