A Algorithm Of Eliminating The Congestion By Sensitivity Matrix Based On Unified Marginal Price Settlement

With the development of reforms in our country, Power Market must be put intopractice in electrical industry. The first step is opening Generation Market. This paperis presented to study how to purchase electricity from power plants both economicallyand satisfying users' requirements, on the premise of ensuring the security ofelectrical network and energy quality.According to the practical quote curve, we use the Merit-order Method to solvethe Unit Commitment problem, at the aim of minimizing the cost of purchasingelectricity from power plants, based on the unified marginal price. About congestionmanagement, this paper proposes a new congestion management model based on thedouble linear programming, considering the disadvantage of eliminating congestionmethod by the single line at one time. The algorithm of Congestion Management is asfollows: first of all, computing every power plant's sensitivity to all overloading lines,and forming sensitivity matrix;secondly, forming the equal sensitivity matrixrestrictions;at last, forming the linear programming model with the unequalrestrictions of the power system and the minimum of the increased cost. The papercalculates the result of the model by double linear programming. Namely, after thefirst linear programming, we transform the coefficients of the negative adjustment tozero, make the second linear programming, and get the final result. Finally, wemodify the generators' active power using the mentioned result. This algorithm caneliminate the congestion fast, and avoid the possible shake phenomenon because ofeliminating congestion method by the single line at one time.The correctness and validity of the proposed algorithm have been proved by theIEEE-9 and IEEE-30 test cases.