Dynamic security constrained congestion management in competitive electricity markets

This paper studies dynamic security constrained congestion management in an unbundled electric power system. Making a system dynamically secure will require the re-dispatch of generators, and achieving a commercial transparent and technically justifiable approach, therefore, is very important. In this paper, the transient energy margin using the transient energy function approach has been applied to calculate the stability margin of the system after clearing a typical fault. Re-dispatch is undertaken if this margin is inadequate. It is possible to reschedule the real power generator along with curtailment of real power load to make the system dynamically secure after a fault. In some cases, congestion can be avoided by using a costlier generator, which increases the nodal prices of the system. In extreme cases, congestion can only be avoided by curtailment of transactions. A conceptually reasonable and computationally feasible approach for the solution of this problem has been developed and is illustrated by an example