The example system describes a 225/90 kV transmission system. Loads are distributed throughout the network, but mainly concentrated at the 90 kV substations. Power plants are connected via step-up transformers to both 225 and 90 kV substations. Long 225 kV transmission lines are compensated with line reactors and some loads are shunt compensated. Two wind turbine groups are also considered (East and West).


There are two study cases in the load flow folder, high Load and low load each of them related to a corresponding operation scenario. In both cases, the two variations defining the wind parks are active (“Stage 1 WPEast” is set as recording). A boundary is defined in order to monitor the flow from the 275 kV corridor.

The base conditions for the power flow simulations are:

• All generators are connected
• Gen_S2 generator set as reference machine
• Station controllers defined for power plants S11, S2 and S4 so that they control the voltage at one of their substation terminal