Energy reserve requirements (RRs) provision is crucial for transmission system operators to ensure reliable and safe operation. Moreover, generation company strategies in the energy and service markets are based on expected power and reserve requests in real-time and day-ahead operations. An approach to evaluate three tertiary RRs is proposed in this paper, accounting for load and renewable forecast errors and generation outage. The RRs estimation is carried out by a statistical analysis based on a seasonal classification of load demand and RES production compared with a reference system. Finally, the feasibility of the estimated RRs with available margins is assessed. This approach is applied to the NREL 118-bus test system.

This paper concerns with the determination of a suitable level of overplanting for photovoltaic systems. For this purpose, six futuristic operational scenarios for the Dutch electrical power system are generated for year 2050. A synthetic model is developed by using DIgSILENT Power Factory 2022 SP3 to investigate the steady-state systemic performance in each operational scenario, taking into account three cases with different levels of overplanting. Power flow calculations are conducted to reflect on the resulting voltage profiles and active power losses as well as on the implications on the required network upgrades (e.g. addition of lines, transformers, and reactive power compensation devices).

Power electronic interfaced generation (PEIG) has become significantly dominant in the electrical power grid. This development is leading to a decrease in systemic inertia and damping against electrical oscillations. This causes the introduction of new and faster dynamic phenomena. One of these phenomena is sub-synchronous control interaction (SSCI), occurring as sub-synchronous oscillations (SSOs) in the system. Several real-world events reported so far have been related with large wind power plants (WPPs) and the improper tuning of the grid side converter (GSC) of (type-4) fully rated converter (FR C) wind turbines. As other PEl G have similar topologies and control systems, it is a very relevant topic. Weak grid conditions often contribute to the risks of SSO events. This paper proposes supplementary wide-area damping (WAD) to the control system of the GSC, focused on damping excursions of the phase locked loop (PLL). Signals measured by a remote phasor measurement unit (PMU) are communicated to the control system, which uses it for dynamic damping control. The effects of the WAD are tested by comparing the results of linearization-based eigenvalue analysis with and without the addition of WAD. Supplementary analysis conducted by using time-domain simulations and Prony analysis confirm the positive effect of WAD. Numerical tests are performed in DlgSILENT PowerFactory 2023 SP2 on a modified IEEE-39 bus test system.

The operation schedule of the power generation units in electrical power systems is determined by the optimisation problem known as unit commitment (UC), aiming at minimising the total cost considering the generation constraints. To obtain a feasible solution from the network perspective, the security-constrained UC (SCUC) problem has been defined to embed the network constraints in the optimisation problem as well. Also, the higher penetration of renewable energy sources (RES) has increased the difficulty of UC problem, mainly due to the uncertainty and the high variability of RES. This paper proposed a SCUC with economic dispatch (SCUCED) optimisation developed in two stages. The first one is the solution of a merit-order based zonal day-ahead market (ZDAM) optimisation to define a preliminary generation schedule. In the second stage, the SCUCED is solved based on AC load flow routines and sensitivity factors to embed the full network representation. The approach is applied to a modified version of the IEEE 39-bus test system.

The frequency stability of the power system is challenged by the high penetration of power electronic interfaced renewable energy sources (RES). Energy storage systems (ESS) are used to supply extra power injection to enhance the frequency stability during a disturbance. This paper presents a novel approach for improving the frequency dynamics by incorporating a designed ultracapacitor (UC) with a fully decoupled wind power generation (FDWG) unit. To this aim, a suitable model implementation of UC for real-time simulations is presented. The model constitutes a parallel RC branch, which is appropriate for illustrating the relevant fast UC dynamics that occur within the first milliseconds of the time period of action for fast active-power frequency control services. The frequency performance achieved by the support of the FDWG equipped with UC is compared against the performance achieved by using electrical batteries. The comparison includes the application of droop-derivative frequency control.

The Phase I of Paraguaná wind farm is designed to provide 32.4 MW to the Paraguaná power system using 24 MADE AE-61 wind turbines. This generation unit uses single cage induction generator which requires reactive power support during the power production. Three type of dynamic reactive power compensation are evaluated in this paper: Mechanically-switch shunt capacitor, static var compensator and static synchronous compensator (STATCOM). Time-domain simulations using DIgSILENT®PowerFactory™ over the Paraguaná power system are used to evaluate the dynamic behavior of bus voltages during and after a three-phase fault. Results demonstrate STATCOM provides the best reactive power support to the network to compensate the large amount of reactive power absorbed by the wind turbine after fault and thus they considerably improve the recovery of system voltages.

La Guajira Peninsula on the western part of Venezuela has been defined as a potential area for wind power developments and one of them is La Guajira wind farm. This paper establishes the systemic impact of the integration of the Phase 1 of this wind farm on the western area of Venezuelan power system. Three integration scenarios are defined in this paper considering the connection of transmission lines on either 138 kV or 24 kV. The steady-state performance is evaluated considering the changes on the local voltage profile. The dynamic behavior of the western Zulia power system is evaluated trough response of the main electro-mechanical variables obtained from time-domain simulations. Two large contingencies are considered. The main contribution of this paper is demonstrates the positive effect of the wind farm integration on 138 kV, the low voltage fault through capabilities on the wind turbine enables good voltage profile during fault condition and fast post contingency voltage recovery.

Load modeling is a very important aspect of voltage stability analysis as load characteristics governs voltage behavior. In this paper a compact solution to extract parameters of a load model is presented, which includes estimation of power components based on Improved Recursive Newton Type Algorithm and estimation of parameters of a dynamic Load Model using Genetic Algorithms. The paper demonstrates the influence of the preprocessing of the instantaneous values on the final estimation of load parameters. All tests were carried out using 9-buses P.M.Anderson system built in DIgSILENT.