A New Approach for Corrective and Preventive Control to Unsolvable Case in Power Networks having DERs

  • Dinh, Hung Nguyen (Dept. of Electrical Engineering and Computer Science, Seoul National University) ;
  • Nguyen, Minh Y. (Dept. of Electrical Engineering and Computer Science, Seoul National University) ;
  • Yoon, Yong Tae (Dept. of Electrical Engineering and Computer Science, Seoul National University)
  • Received : 2012.06.13
  • Accepted : 2012.10.23
  • Published : 2013.05.01


Recently, Korean system operating conditions have gradually approached an upper limit. When a contingency occurs, the power system may have no solutions. Different from the cases of bad initial guesses or the solutions are too close to the solvability boundary in which numerical methods can be applied, for unsolvable cases, the only way to restore solvability would be structure modifications. In this paper, a new approach for corrective and preventive control to such cases is proposed in two steps: (i) finding any solution regardless its feasibility; (ii) for the infeasible solution, make it feasible with additional modifications at load buses having Distributed Energy Resources. The test case built based on the peak load profile of 2008 by KEPCO including 1336 buses is analyzed. Since reactive power compensation is optimized to restore solvability, all demands are met, therefore no blackouts happen. The proposed method was integrated in the LP program designed by power21 Corporation.


Supported by : Korean Institute of Energy Technology Evaluation and Planning (KETEP)


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