ERACSExercises Dr. M.W.Renton Page 1 of 1 04/02/14 Power Systems (ERACS) Case-Study Exercises 1. In ERACS create the IEE case study network as described in the ERACS Tutorial Manual. Using both the building block method and the incident matrix, determine the [Ybus] matrix for the example network 2. Run a loadflow analysis on the IEE case-study circuit in Q.1. with the 11 kV bussection switch open between busbars 3A and 3B. Display only the following:  On grid infeed, loads, generators, transformers, lines and bus-sections: real and reactive powers.  On busbars: p.u. voltage and phase angle. 3. Increase the 11 kV load to 25 MW, 5 MVAr. Predict the result below, then verify it by running a new loadflow analysis. 4. Close the 11 kV bus-section switch. Again predict and verify the outcome. 5. Return the 11 kV load to 5 MW, 5 MVAr, then simulate a grid failure (outage) by opening the appropriate switch. Predict and verify the outcome. 6. With the grid switched out, reduce the 33 kV load to 0 MW, 0 MVAr. Predict and verify the outcome. 7. Try various other scenarios to observe the behaviour of the system: e.g. switch out all generation and the grid; vary the different generator outputs; vary the loads etc.