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Presents a Norton approach for modeling electric power distribution networks where the system configuration is not fully known. Influence of capacitor switching on network harmonic generation; Measurement of the harmonic current or voltage source; Accuracy of modeling a distribution network as a current or voltage source.

Details the incorporation of the integer representation of a spinning reserve into an integer model of generation scheduling. Significance of power system scheduling; Contribution of on-line units on the spinning reserve; Application of variable splitting and Lagrange relaxation models to decompose the problems.

Hydropower scheduling in day-ahead electricity markets is complex due to uncertainty in the electricity price. Internal cascade dependency of hydro power plants can also increase this complexity. One way to overcome this complexity is to replace the original hydropower system by an equivalent system, which provides simulation results sufficiently close to the ones of the original system. This paper presents a method to obtain multi-station equivalent models using a bilevel optimization problem, where the objective is to minimize the difference in outcomes between the original and the equivalent models. This bilevel problem is then transformed into a single-level optimization problem that can be solved using standard optimization techniques. Finally, the errors between the simulation results of the original and equivalent hydropower models are computed and analyzed for a Swedish system to show the accuracy of different multi-station equivalents. [ABSTRACT FROM PUBLISHER]

The current study applies the cost-benefit analysis method to determine the optimal amount of spinning reserve. However, it is difficult for the method to handle large size problem, like large interconnected power systems with several control areas, directly. Therefore, this paper proposes a power system equivalent for the original system to reduce the complexity of the original problem. According to the proposed algorithm, each area of the system is first modeled by an equivalent system, obtained by the REI (radial – equivalent – independent) method, and an interconnected REI equivalent is obtained for the original interconnected system. A cost-benefit analysis is then performed to determine the spinning reserve requirements of both the original and equivalent systems. The cost-benefit algorithm considers either the SCUC (security constrained unit commitment) or the SCED (security constrained economic dispatch). Finally, the proposed interconnected REI equivalent is evaluated by comparing the spinning reserve of each control area in the original system with that in the equivalent system. Numerical studies are performed on two IEEE test systems. [ABSTRACT FROM AUTHOR]