Based on a new perspective in coordinating with the traditional ''N-1'' criteria and system risk, a real-time electricity market model is presented, in which the system risk is employed to model the system's overall security level. This new model is called the risk-based security-constrained economic dispatch (RB-SCED). Relative to the securityconstrained economic dispatch (SCED) used in the power industry today, the RB-SCED finds more secure and economic operating conditions. It does this by obtaining solutions that achieve a better balance between post-contingency flows on individual branches and the overall system risk. The method exploits the fact that, in a SCED solution, some postcontingency branch flows which exceed their limits impose little risk while other post-contingency branch flows which are within their limits impose significant risk. The RB-SCED softens constraints for the former and hardens constraints for the latter, thus achieving simultaneous improvement in both security and economy. In this work, the basic concept and the mathematical formulation of the RB-SCED model are systematically described. Experimental results on a 9-bus system and the ISO New England actual system have demonstrated the advantages of RB-SCED over SCED.

The research work presented in this paper represents a step forward with respect to previous approaches in the field of electricity market operating performance evaluation in China. A new method for the comprehensive evaluation of electricity markets is presented through the combined use of the fuzzy set theory and analytic hierarchy process (AHP). The fuzzy set approach is employed to identify the membership degree of each index to various evaluation results, while the AHP is used to acquire the sets of weighting factors. This method represents a unified integration of the quantitative results from fuzzy analysis with the qualitative results from the judge of relevant experts, and is generally applicable. Finally, an example is served for demonstrating the essential features of the developed method.

No abstract