A Novel Multifrequency Current Reference Calculation to Mitigate Active Power Fluctuations

Moriano, Javier; Rizo, Mario; Bueno, Emilio; Martı́n, Rosario; Rodríguez, Francisco

doi:10.1109/tie.2017.2686319

Cited by 17 publications

(17 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…An advanced control strategy for the generator of a wind turbine based on Sliding Mode Control is introduced by Merabet et al and Evangelista et al . A novel multifrequency power oscillations mitigation algorithms to improve the grid connection of the wind turbine are proposed in the work of Moriano et al…”

Section: Introductionmentioning

confidence: 99%

“…An advanced control strategy for the generator of a wind turbine based on Sliding Mode Control is introduced by Merabet et al 11 and Evangelista et al. 12 A novel multifrequency power oscillations mitigation algorithms to improve the grid connection of the wind turbine are proposed in the work of Moriano et al 13 Regarding the yaw operation of a wind turbine, different studies such as the one presented by Gebraad et al 14 have been introduced in the literature to optimize the power production of a wind farm by calculation of the optimal yaw angle for individual wind turbines. Munters et al 15 present a gradient-descent-based algorithm for the calculation of this optimal yaw angle.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Performance enhancement of the artificial neural network–based reinforcement learning for wind turbine yaw control

et al. 2019

View full text Add to dashboard Cite

The yaw angle control of a wind turbine allows maximization of the power absorbed from the wind and, thus, the increment of the system efficiency. Conventionally, classical control algorithms have been used for the yaw angle control of wind turbines. Nevertheless, in recent years, advanced control strategies have been designed and implemented for this purpose. These advanced control strategies are considered to offer improved features in comparison to classical algorithms. In this paper, an advanced yaw control strategy based on reinforcement learning (RL) is designed and verified in simulation environment. The proposed RL algorithm considers multivariable states and actions, as well as the mechanical loads due to the yaw rotation of the wind turbine nacelle and rotor. Furthermore, a particle swarm optimization (PSO) and Pareto optimal front (PoF)-based algorithm have been developed in order to find the optimal actions that satisfy the compromise between the power gain and the mechanical loads due to the yaw rotation. Maximizing the power generation and minimizing the mechanical loads in the yaw bearings in an automatic way are the objectives of the proposed RL algorithm. The data of the matrices Q (s,a) of the RL algorithm are stored as continuous functions in an artificial neural network (ANN) avoiding any quantification problem. The NREL 5-MW reference wind turbine has been considered for the analysis, and real wind data from Salt Lake, Utah, have been used for the validation of the designed yaw control strategy via simulations with the aeroelastic code FAST.

show abstract

Section: Introductionmentioning

confidence: 99%

mentioning

confidence: 99%

Performance enhancement of the artificial neural network–based reinforcement learning for wind turbine yaw control

et al. 2019

View full text Add to dashboard Cite

show abstract

“…Nevertheless, most case studies only consider positive and negative sequences because zero-sequence voltages of unbalanced voltage dips do not exist in three-wire systems, nor can they propagate to the secondary side of star-ungrounded or delta-connected transformers in four-wire systems [15]. Even for unbalanced systems with zero-sequence voltage, four-leg inverter topologies can eliminate zero-sequence current with appropriate control [21].The multifrequency current reference calculator purpose, just taking into account positive and negative sequences, has been partly fulfilled for DER applications [5] as well as DFIG ones [10,22]. Both proposals are defined in synchronous reference frames (SRF), hence, coordinate transformations are required.…”

mentioning

confidence: 99%

“…Therefore, frequency-adaptive techniques [25] must be applied in order to accomplish the control objective of constant active power, as is shown in this paper.From the grid code operation point of view, the injected harmonic sequence currents are limited by the total harmonic distortion (THD) standards [26]. In order to achieve standards limitations, any of the harmonic sequence currents could be set to zero or current HD minimization could be performed [5]. Both approaches must sacrifice the cancellation of one power ripple component, and the smallest power ripple is chosen for the optimum performance.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Enhanced Current Reference Calculation to Avoid Harmonic Active Power Oscillations

Serrano

Moriano²,

Rizo

et al. 2019

Energies

Self Cite

View full text Add to dashboard Cite

Energy storage systems play a key role in the rise of distributed power generation systems, hence there is great interest in extending their lifetimes, which are directly related to DC current ripple. One of the ripple sources is the low-frequency active power fluctuations under unbalanced and distorted grid voltage conditions. Therefore, this paper addresses a multifrequency control strategy where the harmonic reference currents are calculated to reduce harmonic active power oscillations. The stationary reference frame (StRF) approach taken here improves the precision and computational time of the current reference calculation method. Additionally, in order to ensure safe converter operation when a multifrequency reference current is provided, a computational efficient peak current saturator is applied while avoiding signal distortion every time step. If the injected current harmonic distortion is to be minimized, which is a feature included in this work, the peak current saturator is a necessary requirement. Active power ripple is reduced even with frequency variations in the grid voltage using a well-known frequency-adaptive scheme. The simulation and experimental results prove the optimized performance for the control objective: power ripple reduction with minimum current harmonic distortion.Energies 2019, 12, 4075 2 of 21 torque pulsations [9]. Besides, on doubly fed induction generators (DFIGs) for wind turbines, active power oscillations are related to electromagnetic torque ripples that increase the mechanical stress on the turbine system [10].The harmonic power oscillations in three-phase three-wire AC electrical systems come from the presence of distorted or unbalanced grids. Therefore, the control strategy aims to regulate the instantaneous active power at a constant value by injecting the suitable currents into the grid. The current reference could be calculated by means of the active and reactive power theory, first introduced in Reference [11]. From that theory, many works have dealt with the regulation of active power oscillations when grid imbalances [12,13] or grid faults [14][15][16] are faced by the power converter. However, these methodologies only remove the second harmonic power ripple due to the appearance of fundamental negative sequence (FNS) voltage and its interaction with the fundamental positive sequence (FPS) current. In distorted grids, there are higher even harmonic power ripples due to other harmonic sequence voltages (−5, +7, −11, +13). Hence, an effective multifrequency current reference calculator is required by the algorithm to accomplish the power ripple removal.The presented control objective has an unavoidable characteristic in three-phase three-wire systems-the elimination of active power oscillations implies more reactive power fluctuations [13,16]. Previous publications such as References [17][18][19] claimed the elimination of both active and reactive power oscillations, simultaneously. However, this approach in three-wire systems leads to the injection of zero-sequence...

show abstract

Virtual Park‐based control strategy for grid‐connected inverter interfaced renewable energy sources

Çelík¹,

Meral²,

İnci

2019

IET Renewable Power Generation

View full text Add to dashboard Cite

Unbalanced grid faults are the most severe perturbations which degrade the performance of grid-connected inverter interfaced renewable energy sources (IIRESs). In this regard, this study proposes a novel control strategy that provides optimum use of the power capability of the grid-connected IIRES under unbalanced grid fault conditions. One of the major contributions to previous methods is to propose a fast and robust improved Virtual Park (VP) sequence extractor to implement the reference current generator (RCG). The dynamic response of the grid-connected IIRES has also enhanced thanks to the proposed VP sequence extractor. The computing of maximum active power injection and simultaneously amplitude of phase currents is embedded into a new algorithm based the RCG to meet the aimed control objectives. The controllability and minimisation of active and reactive power oscillations are also formulated and carried out with only one control parameter. Another contribution of this study is to prevent overcurrent issues with peak current limitation control. Reference for active power is online computed based on the maximum current injection at inverter capacity for overcurrent protection. The validating effectiveness of the proposed solution is performed by a comprehensive set of cases to show the shortcomings of previous similar studies.

show abstract

A Novel Multifrequency Current Reference Calculation to Mitigate Active Power Fluctuations

Cited by 17 publications

References 26 publications

Performance enhancement of the artificial neural network–based reinforcement learning for wind turbine yaw control

Performance enhancement of the artificial neural network–based reinforcement learning for wind turbine yaw control

Enhanced Current Reference Calculation to Avoid Harmonic Active Power Oscillations

Virtual Park‐based control strategy for grid‐connected inverter interfaced renewable energy sources

Contact Info

Product

Resources

About