Active distribution networks planning with high penetration of wind power

YesIn this paper, a stochastic method for active distribution networks planning within a distribution market environment considering multi-configuration of wind turbines is proposed. Multi-configuration multi-scenario market-based optimal power flow is used to maximize the social welfare considering uncertainties related to wind speed and load demand and different operational status of wind turbines (multiple-wind turbine configurations). Scenario-based approach is used to model the abovementioned uncertainties. The method evaluates the impact of multiple-wind turbine configurations and active network management schemes on the amount of wind power that can be injected into the grid, the distribution locational marginal prices throughout the network and on the social welfare. The effectiveness of the proposed method is demonstrated with 16-bus UK generic distribution system. It was shown that multi-wind turbine configurations under active network management schemes, including coordinated voltage control and adaptive power factor control, can increase the amount of wind power that can be injected into the grid; therefore, the distribution locational marginal prices reduce throughout the network significantly

Upravljanje proizvodnom jedinicom spojenom na mrežu tijekom nesimetričnih napona na mreži temeljeno na kliznom režimu

The increasing presence of inverter-based distributed generation (DG) units in distribution networks (DNs) requires control methods that achieve high performance not only during normal operating conditions, but also under unbalanced conditions. With a high probability, a type of voltage unbalance in DNs is unequal three-phase voltage magnitudes at the fundamental system frequency. This can occur temporarily due to faults or permanently due to uneven distribution of unbalanced loads, on the three-phases of the DN. This paper proposes a sliding mode (SM) based controller for grid-connected DG units, under unbalanced grid voltage condition. The proposed control strategy employs a nonlinear control scheme to directly cancel out the negative-sequence (NS) components of DG output current under unbalanced voltage condition; and directly regulate the positive-sequence (PS) active and reactive power injected by DG units to main-grid. The control method proposed in this paper is shown to be robust and stable system parameter uncertainties. The validity and effectiveness of the proposed controller is verified by using time-domain simulation studies, under the MATLAB/Simulink software environment.Povećanje udjela distribuiranih proizvodnih jedinica povezanih na mrežu frekvencijskim pretvaračima zahtjeva metode upravljanja koje dobro djeluju tijekom normalnih uvjeta na mreži kao i u nesimetričnim uvjetima. Najčešći tip nesimetričnog napona na distribuiranoj jedinici je nesimetrična amplituda trofaznog napona na fundamentalnoj frekvenciji. To se događa privremeno zbog kvarova ili trajno zbog nejednake distribucije nesimetričnih tereta na tri faze distribuirane proizvodne jedinice. U ovom radu predlaže se regulator temeljen na kliznom režimu za upravljanje proizvodnom jedinicom spojenom na mrežu tijekom nesimetričnih napona na mreži. Predložena strategija upravljanja koristi nelinearnu shemu upravljanja kako bi se izravno poništile inverzne komponente izlazne struje tijekom nesimetričnih uvjeta; i izravno upravlja direktnom komponentom radne i jalove snage isporučene u mrežu. Metoda upravljanja predložena u ovom radu pokazala se kao robusna i stabilna uz nesigurne parametre sustava. Opravdanost i učinkovitost predloženog regulatora provjerena je korištenjem simulacija u MATLAB/Simulinku

Design of Ancillary Services for Battery Energy Storage Systems to Mitigate Voltage Unbalance in Power Distribution Networks

power system, voltage unbalance issues are expected to exacerbate. Single{phase connectedphotovoltaic (PV) panels may cause unequal three{phase power ows, resultingin unbalanced grid currents and voltages. In addition, the random charging behaviour ofPlug{in Hybrid Electric Vehicles (PHEVs) equipped with single{phase on{board chargersis expected to further contribute to voltage unbalance rise as the number of thesedevices grows. If voltage unbalance increases to unacceptable levels, it may have adverseeects on power system operation and on the equipment connected to it. Traditionally,the phase swapping technique has been deployed by distribution system operators forvoltage unbalance mitigation, while other mitigating techniques include the deploymentof power electronics-based devices. The majority of the devices reported in the literatureare based on three-phase congurations, including series and parallel active power lters,unied power quality conditioners (UPQCs), static synchronous compensators (STATCOMs)and, more recently, three-phase distributed generation (DG) inverters.This research proposes the use of single-phase battery energy storage systems (BESSs)for the provision of phase balancing services, which has been considered only in a few literatureworks, with most of these research papers focusing on three-phase BESSs. In thisthesis, a novel control strategy is proposed for single-phase BESS units to compensatevoltage unbalance by injecting both active and reactive power simultaneously. The proposedapproach is based on the coordinated operation of three independent single-phaseBESS inverters using local voltage and current measurements.Initially, a comprehensive literature review is performed with the following aims: arobust classication of the ancillary services currently oered by BESSs, harmonisation ofthe notation found in the literature for ancillary services, and identication of potentialfuture applications of BESSs to power grids with large number of Low Carbon Technologies(LCTs). Then, the eectiveness of the proposed voltage unbalance compensationmethod is validated in the simulation environment, where two realistic models of distributionsystems are developed. Next, the impact of increasing PV and EV penetrationlevels on voltage unbalance for a typical UK distribution system is assessed based on adeterministic approach. The control strategy is validated experimentally by carrying outHardware-In-The-Loop (HIL) tests. Finally, an equivalent model of the distribution systemand BESS inverter is derived, which allows to carry out a preliminary probabilisticstudy to cater for the uncertainties related to the location and size of the PVs and EVs,and to evaluate the voltage unbalance levels without and with the BESSs controlled toprovide voltage unbalance compensation.It is concluded that the proposed BESS control system may eectively reduce thevoltage unbalance levels under various loading and generating conditions

Análisis de armónicos variando en el tiempo en sistemas eléctricos de potencia con parques eólicos, a través de la teoría de la posibilidad

This paper focuses on the analysis of the connection of wind farms to the electric power system and their impact on the harmonic load-flow. A possibilistic harmonic load-flow methodology, previously developed by the authors, allows for modeling uncertainties related to linear and nonlinear load variations. On the other hand, it is well known that some types of wind turbines also produce harmonics, in fact, time-varying harmonics. The purpose of this paper is to present an improvement of the former method, in order to include the uncertainties due to the wind speed variations as an input related with power generated by the turbines. Simulations to test the proposal are performed in the IEEE 14-bus standard test system for harmonic analysis, but replacing the generator, at bus two, by a wind farm composed by ten FPC type wind turbines.En este trabajo se analiza el impacto de la conexión de parques eólicos, en el flujo de cargas armónicas en un sistema de potencia. Algunos generadores eólicos producen armónicos debido a la electrónica de potencia que utilizan para su vinculación con la red. Estos armónicos son variables en el tiempo ya que se relacionan con las variaciones en la velocidad del viento. El propósito de este trabajo es presentar una mejora a la metodología para el cálculo de incertidumbre en el flujo de cargas armónicas, a través de la teoría de la posibilidad, la cual fue previamente desarrollada por los autores. La mejora consiste en incluir la incertidumbre debida a las variaciones de la velocidad del viento. Para probar la metodología, se realizan simulaciones en el sistema de prueba de 14 barras de la IEEE, conectando en una de las barras un parque eólico compuesto por diez turbinas del tipo FPC. Los resultados obtenidos muestran que la incertidumbre en la velocidad del viento tiene un efecto considerable en las incertidumbres asociadas a las magnitudes de las tensiones armónicas calculadas.Fil: Romero Quete, Andrés Arturo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Instituto de Energía Eléctrica. Universidad Nacional de San Juan. Facultad de Ingeniería. Instituto de Energía Eléctrica; ArgentinaFil: Suvire, Gaston Orlando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Instituto de Energía Eléctrica. Universidad Nacional de San Juan. Facultad de Ingeniería. Instituto de Energía Eléctrica; ArgentinaFil: Zini, Humberto Cassiano. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Instituto de Energía Eléctrica. Universidad Nacional de San Juan. Facultad de Ingeniería. Instituto de Energía Eléctrica; ArgentinaFil: Ratta, Giuseppe. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Instituto de Energía Eléctrica. Universidad Nacional de San Juan. Facultad de Ingeniería. Instituto de Energía Eléctrica; Argentin