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[EN] This paper presents a robust control technique applied to a three-phase shunt active filter based on an NPC inverter, showing the modelling procedure needed to carry out the proposed control. The transfer functions for the control of the currents injected by the active filter are derived. The modelling is based on the abc/dq Park transformation of the AC system variables. The currents injected by the active filter are controlled in the synchronous orthogonal dq reference frame. The proposed robust current control technique is compared to a conventional PI controller in the dq frame, and to a PIS controller in the dq frame, consisting of a PI and resonant controllers synchronized to the frequencies of the nonlinear load current harmonics. On one hand, it is shown that the proposed technique improves the current harmonics compensation obtained by conventional PI control. On the other hand, it is found that the PIS controller is the best suited for current harmonics compensation among the controllers under study. Nevertheless, the RMF controller results in a simpler implementation than the PIS controller. Moreover, the proposed robust control has been applied to the DC-link voltage regulation, and it has been compared to a PI controller. It is shown that the robust control technique improves the dynamic response of the inverter to load steps without the need of a high crossover frequency of the DC-link voltage loop. ; This study was carried out partially with financial support from the Autonomous Government of the Basque Country's GENEDIS 2 project, and under Grant ENE2006-15521-CO3-02/CON of the Spanish Ministry of Science and Technology. ; Munduate, A.; Figueres Amorós, E.; Garcerá, G. (2009). Robust Model-Following control of a three-level Neutral Point Clamped shunt active filter in the medium voltage range. International Journal of Electrical Power & Energy Systems. 31(10):577-588. https://doi.org/10.1016/j.ijepes.2009.03.027 ; S ; 577 ; 588 ; 31 ; 10

1 19 12 11 ; S ; [EN] Central inverters are usually employed in large photovoltaic farms because they offer a good compromise between costs and efficiency. However, inverters based on a single power stage have poor efficiency in the low power range, when the irradiation conditions are low. For that reason, an extended solution has been the parallel connection of several inverter modules that manage a fraction of the full power. Besides other benefits, this power architecture can improve the efficiency of the whole system by connecting or disconnecting the modules depending on the amount of managed power. In this work, a control technique is proposed that maximizes the global efficiency of this kind of systems. The developed algorithm uses a functional model of the inverters¿ efficiency to decide the number of modules on stream. This model takes into account both the power that is instantaneously processed and the maximum power point tracking (MPPT) voltage that is applied to the photovoltaic field. A comparative study of several models of efficiency for photovoltaic inverters is carried out, showing that bidimensional models are the best choice for this kind of systems. The proposed algorithm has been evaluated by considering the real characteristics of commercial inverters, showing that a significant improvement of the global efficiency is obtained at the low power range in the case of sunny days. Moreover, the proposed technique dramatically improves the global efficiency in cloudy days. This work is supported by the Spanish Ministry of Economy and Competitiveness (MINECO), the European Regional Development Fund (ERDF) under Grants ENE2015-64087-C2-2-R and RTI2018-100732-B-C21, and the Spanish Ministry of Education (FPU15/01274). Liberos-Mascarell, MA.; González-Medina, R.; Garcerá, G.; Figueres Amorós, E. (2019). A Method to Enhance the Global Efficiency of High-Power Photovoltaic Inverters Connected in Parallel. Energies. 12(11):1-19. https://doi.org/10.3390/en12112219 Wu, H., Locment, F., & Sechilariu, ...

811 827 17 6 ; S Ackermann, T. (Ed.). (2005). Wind Power in Power Systems. doi:10.1002/0470012684 PSIM 7.0 User's Guide (2006), Powersim Inc. 2006 ; This paper presents a low power wind energy conversion system (WECS) based on a permanent magnet synchronous generator and a high power factor (PF) rectifier. To achieve a high PF at the generator side, a power processing scheme based on a diode rectifier and a boost DC-DC converter working in discontinuous conduction mode is proposed. The proposed generator control structure is based on three cascaded control loops that regulate the generator current, the turbine speed and the amount of power that is extracted from the wind, respectively, following the turbine aerodynamics and the actual wind speed. The analysis and design of both the current and the speed loops have been carried out taking into consideration the electrical and mechanical characteristics of the WECS, as well as the turbine aerodynamics. The power loop is not a linear one, but a maximum power point tracking algorithm, based on the Perturb and Observe technique, from which is obtained the reference signal for the speed loop. Finally, to avoid the need of mechanical sensors, a linear Kalman Filter has been chosen to estimate the generator speed. Simulation and experimental results on a 2-kW prototype are shown to validate the concept. © 2013 John Wiley & Sons, Ltd. Carranza Castillo, O.; Garcerá Sanfeliú, G.; Figueres Amorós, E.; González Morales, LG. (2014). Low power wind energy conversion system based on variable speed permanent magnet synchronous generators. Wind Energy. 17(6):811-827. doi:10.1002/we.1598 Muyeen, S. M., Shishido, S., Ali, M. H., Takahashi, R., Murata, T., & Tamura, J. (2008). Application of energy capacitor system to wind power generation. Wind Energy, 11(4), 335-350. doi:10.1002/we.265 Ladenburg, J. (2009). Stated public preferences for on-land and offshore wind power generation-a review. Wind Energy, 12(2), 171-181. doi:10.1002/we.308 Maeda, T., & Kamada, Y. (2009). ...

1056 1066 26 4 ; S ; This paper presents a new active anti-islanding detection method for distributed power generation systems. This method is based on introducing a disturbance at the inverter output and observing the behavior of the voltage at the point of common coupling (PCC), which depends on the impedance connected to the PCC in an islanding situation. The islanding detection is based on the Goertzel algorithm. Velasco De La Fuente, D.; Trujillo Rodríguez, CL.; Garcerá Sanfeliú, G.; Figueres Amorós, E. (2011). An active Anti-islanding method based on phase-PLL perturbation. IEEE Transactions on Power Electronics. 26(4):1056-1066. doi:10.2089643

706 717 56 3 ; S ; [EN] An accurate small-signal model of three-phase photovoltaic (PV) inverters with a high-order grid filter is derived in this paper. The proposed model takes into account the influence of both the inverter operating point and the PV panel characteristics on the inverter dynamic response. A sensitivity study of the control loops to variations of the dc voltage, PV panel transconductance, supplied power, and grid inductance is performed using the proposed small-signal model. Analytical and experimental results carried out on a 100-kW PV inverter are presented. Figueres Amorós, E.; Garcerá, G.; Sandia Paredes, J.; González Espín, FJ.; Calvo Rubio, J. (2009). Sensitivity Study of the Dynamics of Three-Phase Photovoltaic Inverters With an LCL Grid Filter. IEEE Transactions on Industrial Electronics. 56(3):706-717. doi:10.1109/TIE.2008.2010175