Behavior of Power System Equilibrium Points in Dynamic Available Transfer Capability Calculation

  • Mohamed Shaaban Department of Electrical and Electronic Engineering, Faculty of Engineering, Universiti Malaysia Sarawak, 94300 Kota Samarahan, Sarawak, Malaysia
Keywords: Available transfer capability (ATC), electric power system, equilibrium point, optimization


Available Transfer Capability (ATC) is of fundamental importance in electric power system planning and operation. The calculation of firm ATC in a power market environment is carried out based on day-ahead market dispatch with a set of security constraints. Incorporating dynamic security constraints into the ATC calculation not only renders a heavier burden on the computational approach, but also manifests complex system behavior in the neighborhood of its equilibrium points. This paper specifically highlights exotic system characteristics encountered during dynamic ATC calculation. The problem of ATC calculation is modeled as a nonlinear mathematical programming problem to maximize the power transfer subject to system technical and operating constraints. The dynamic ATC constraints are represented via the quadratic approximation of the stable manifold of the controlling unstable equilibrium point (UEP). A case study on the IEEE WECC 3- machine, 9-bus power system is presented and analyzed.


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How to Cite
Shaaban, M. (2018). Behavior of Power System Equilibrium Points in Dynamic Available Transfer Capability Calculation. Journal of Applied Science & Process Engineering, 5(1), 242-248.