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This paper introduces a robust system designed to effectively manage and enhance the electrical output of a Wind Energy Conversion System (WECS) using a Cascaded Doubly Fed Induction Generator (CDFIG) connected to a power grid. The solution that was investigated is the use of a CDFIG that is based on a variable-speed wind power conversion chain. It comprises the electrical and mechanical connection of two DFIGs through their rotors. The originality of this paper lies in the innovative application of a fuzzy logic controller (FLC) in combination with a CDFIG for a WECS. To demonstrate that this novel configuration enhances control precision and performance in WECSs, we conducted a comparison of three different controllers: a proportional–integral (PI) controller, a fractional PID (FPID) controller, and a fuzzy logic controller (FLC). The results highlight the potential of the proposed system in optimizing power generation and improving overall system stability. It turns out that, according to the first results, the FLC performed optimally in terms of tracking and rejecting disturbances. In terms of peak overshoot for power and torque, the findings indicate that the proposed FLC-based technique (3.8639% and 6.9401%) outperforms that of the FOPID (11.2458% and 10.9654%) and PI controllers (11.4219% and 11.0712%), respectively. These results demonstrate the superior performance of the FLC in reducing overshoot, providing better control stability for both power and torque. In terms of rise time, the findings show that all controllers perform similarly for both power and torque. However, the FLC demonstrates superior performance with a rise time of 0.0016 s for both power and torque, compared to the FOPID (1.9999 s and 1.9999 s) and PI (0.0250 s and 0.0247 s) controllers. This highlights the FLC's enhanced responsiveness in controlling power and torque. In terms of settling time, all three controllers have almost the same performance of 1.9999. An examination of total harmonic distortion (THD) was also employed to validate the superiority of the FLC. In terms of power quality, the findings prove that a WECS based on an FLC (0.93%) has a smaller total harmonic distortion (THD) compared to that of the FOPID (1.21%) and PI (1.51%) controllers. This system solves the problem by removing the requirement for sliding ring–brush contact. Through the utilization of the MATLAB/Simulink environment, the effectiveness of this control and energy management approach was evaluated, thereby demonstrating its capacity to fulfill the objectives that were set. [ABSTRACT FROM AUTHOR]

This article proposes the use of a deep reinforcement learning method—and precisely a variant of the deep deterministic policy gradient (DDPG) method known as twin delayed DDPG, or TD3—for maximum power point tracking in wind energy conversion systems that use permanent magnet synchronous generators (PMSGs). An overview of the TD3 algorithm is provided, together with a detailed description of its implementation and training for the considered application. Simulation results are provided, also including a comparison with a model‐based control method based on feedback linearization and linear‐quadratic regulation. The proposed TD3‐based controller achieves a satisfactory control performance and is more robust to PMSG parameter variations as compared to the presented model‐based method. To the best of the authors' knowledge, this article presents for the first time an approach for generating both speed and current control loops using DRL for wind energy conversion systems. [ABSTRACT FROM AUTHOR]

The paper proposes a novel speed sensor‐less stator flux‐oriented vector control of dual‐stator induction generator suitable for high‐power applications in grid‐tied wind energy conversion system. In this control strategy, the magnitude and angle of the flux are directly estimated by the measured stator voltages and currents. As the voltage and current sensors are placed on the stationery stator part, therefore, the proposed control strategy does not affect the robustness of the machine compared to the conventional rotor flux‐oriented vector control where the sensors need to be mounted on the rotating part of the machine. Moreover, the proposed speed encoder‐less stator flux‐oriented vector control eliminates the use of speed encoder, thereby reducing the cost and eliminating the error caused due to faulty speed measurement by the speed encoder of the overall system. The performance of the novel speed sensor‐less stator flux‐oriented vector control scheme has been verified by simulation and then experimentally on a 2 hp, 415 V, 50 Hz, three‐phase dual‐stator induction generator drive. The control strategy was implemented through dSPACE 1104 DAC card. From the simulated and the experimental results, it is evident that the proposed control strategy reflects improved performance w.r.t. conventional rotor flux‐oriented vector control. [ABSTRACT FROM AUTHOR]

In this study, a method for fault detection of a permanent magnet synchronous generator (PMSG) wind turbine is proposed. The dynamic model of the wind energy conversion system is simulated and the system's fault is diagnosed using a proposed terminal sliding mode observer (TSMO). The nonlinear state-space equations of the closed-loop wind turbine are derived, which include a robust adaptive controller that is implemented for maximum power capture and a PI controller that is designed for pitch angle control. Then, utilising a new approach, a TSMO is designed for estimating the states and faults in a finite time. The stability and convergence of the states and fault estimation error are investigated via the Lyapunov stability theory. A $ 3kw $ 3 kw PMSG wind turbine is simulated and using TSMO the states are estimated and a blade imbalance fault (BIF) fault is detected. The state and fault estimation errors converge to zero in a finite time. [ABSTRACT FROM AUTHOR]

The green goals imposed by many countries and the increasing application of renewable energy systems are bringing power electronics to the center of attention. Of particular interest are the wide band-gap devices, as they offer important benefits when considering the efficiency increase and volume reduction. Consequently, they can be viably adopted in renewable energy sources. In this paper, a 2 MW Doubly Fed Induction Generator (DFIG) based Wind Energy Conversion System (WECS) with a bidirectional partial-scale frequency converter composed of two back-to-back converters is considered. The main contribution of the paper is a result of comprehensive comparisons conducted for the two systems: DFIG WECS based on a Si-IGBT converter and DFIG WECS based on a SiC-MOSFET converter in terms of efficiency, volume, and cost. The performed comparison is also a fair comparison, being the selected modules are of the same power ratings. In this way, the previously unspecified but valuable decision-making process regarding the selection of power electronic modules suitable for DFIGs is facilitated. The thermal analysis has been implemented in PLECS, together with the converter control. The realistic libraries obtained from the manufacturers have been included for different power modules. The findings highlight the advantages of employing the Silicon Carbide-based converter in terms of minimizing the size and cost of passive components. They also offer insights on what is needed in order to make the Silicon Carbide solution the absolute best candidate.

In this study, the integral linear quadratic regulator (LQR) with servomechanism for machine-side power converter in PMSG-based variable-speed wind energy conversion systems (WECSs) has been proposed. The solution of the algebraic Riccati equation (ARE) has been found for the extended dimension of the state space equation of the system. The state vector has been extended with the integral of the angular shaft speed of the permanent magnet synchronous generator (PMSG) to penalize the errors. The maximum power tracking point (MPPT) algorithm is achieved by minimizing tracking errors between the angular shaft speed reference based on wind speed estimation and its actual values in the variable speed WECS. Also, the estimated aerodynamic torque is used to define the reference electromagnetic torque. This is possible when WECS is partially loaded and pitches angles are fixed at the position to generate maximum power. The mean absolute percentage error of the angular shaft speed of the PMSG-based WECS has been reduced by more than 71% under model uncertainty and noise presented case than in the traditional disturbance observers-based compensation scheme. While the disturbance observers for estimation model uncertainty are eliminated, the use of the high order disturbance observer for aerodynamic torque estimation proved to be necessary to enhance the reliability of wind speed sensors and hence the whole WECS.

A significant problem is enhancing the reliability of the wind energy conversion system (WECS), when that runs in unpredictable weather. Therefore, it is essential to construct a maximum power point tracker (MPPT), a controller for measuring the optimum power that the WECS is expected to generate. Hill climbing-based techniques were used to simulate the tracker, but they had drawbacks in terms of tracking efficiency and speed. The Grey Wolf optimization algorithm (GWO) for modelling MPPT integrated with the WECS is proposed in this work as a novel, effective method. The system is made up of a wind turbine (WT) conjoined to a permanent magnet synchronous generator (PMSG), a 3-phase rectifier that converts the generator's AC output power to direct current (DC), and a boost converter whose input DC voltage is controlled by the MOSFET duty cycle. The goal of the modelling procedure is the system's electrical output power, which is presented as an optimization problem. The results confirmed the GWO-reliability MPPT's in reaching the desired WECS performance. [ABSTRACT FROM AUTHOR]

A significant problem is enhancing the reliability of the wind energy conversion system (WECS), when that runs in unpredictable weather. Therefore, it is essential to construct a maximum power point tracker (MPPT), a controller for measuring the optimum power that the WECS is expected to generate. Hill climbing-based techniques were used to simulate the tracker, but they had drawbacks in terms of tracking efficiency and speed. The Grey Wolf optimization algorithm (GWO) for modelling MPPT integrated with the WECS is proposed in this work as a novel, effective method. The system is made up of a wind turbine (WT) conjoined to a permanent magnet synchronous generator (PMSG), a 3-phase rectifier that converts the generator’s AC output power to direct current (DC), and a boost converter whose input DC voltage is controlled by the MOSFET duty cycle. The goal of the modelling procedure is the system’s electrical output power, which is presented as an optimization problem. The results confirmed the GWO-reliability MPPT’s in reaching the desired WECS performance.

Abstract This study investigates the influence of tip speed ratio (TSR) as maximum power point tracking (MPPT) technique on energy conversion for wind-powered electric vehicles (EVs) charging stations. The data for 14 different models of (EVs) as well as the energy demand profile for El Sherouk city in new Cairo, Egypt, is used in the study. Those vehicles represent the models that are most likely to be used according to the nature of the Egyptian market from economic and technological concerns. This includes range, battery capacity, battery technology and charging methods. charging can be in the form of fast DC, three phases which are suitable for commercial charging stations or a single phase charging suitable for residential use. A simulation is done using MATLAB/Simulink for a wind turbine Permanent Magnet Synchronous Generator (PMSG) system including TSR MPPT algorithm. The energy output is compared with and without implementing the MPPT algorithms to measure the difference in energy. The system simulation optimized by the TSR MPPT algorithm shows an increase in the energy yield by 41.68%. The economic analysis showed a 30% reduction in the levelized cost of energy while utilizing the TSR concerning a bare system without an MPPT algorithm.

The adoption of renewable energy sources, particularly wind energy, has seen remarkable growth in recent years. Wind energy generation requires efficient and reliable generators that can convert wind energy into usable electrical energy. Switched Reluctance Generators (SRGs) have been gaining popularity in wind energy applications due to their high efficiency, reliability, and low maintenance requirements. The multiphase switched reluctance generators are used especially in wind power plants due to their ability to operate in variable speed ranges. In this paper, a MATLAB/SIMULINK based model of Switched Reluctance Generator (SRG) is presented. The obtained results show good agreement under different operating conditions. The obtained results (current, voltage, torque, speed, flux, and angle of generator) are shown in graphs. [ABSTRACT FROM AUTHOR]

The doubly fed induction generator (DFIG)-based wind energy conversion system (WECS) has seen rapid growth all over the world, resulting in a growing access of this source of energy into electrical grids. The low-voltage ride-through (LVRT) capability of the DFIG-based wind turbine must be improved to make it stay connected to the grid during the occurrence of grid faults. Because of its vulnerability to grid disruptions, careful arrangements must be made to the DFIG to keep it connected with the grid. Hence, this paper presents a modified control technique with crowbar protection for improving the LVRT of the WECS. This proposed scheme can be sufficient to meet the LVRT requirements as demanded by grid codes. The fault ride-through capability of the rotor side convertor (RSC) and grid side converter (GSC) is regulated in accordance with grid code requirements. During grid faults, the proposed scheme enhances device recovery by providing reactive power support through the GSC and the stator. The dynamic performance of the proposed scheme is investigated under symmetrical grid disturbances. The operation of the proposed system has been simulated in a MATLAB/Simulink environment for a 2.6 MW-grid-connected DFIG system. [ABSTRACT FROM AUTHOR]

This paper presents a new method to calculate the inversion of the controlled linear/nonlinear dynamic plants which are described by input–output differential equation models. This new U-model-based inverter (U-inverter), cancels both system dynamics and nonlinearities, can be used directly to facilitate the control system design, which the design of U-model-based control (U-control) systems is selected for demonstration in this study. The most important advantage of this U-inverter is that it does not require system state variables, only uses the input/output measurements from the controlled plants. A nonlinear disturbance observer is introduced into the U-control design framework to increase its robustness. The analysis explains the properties of this developed the disturbance observer-based U-control (DOBUC) method and its design procedures. Finally, a wind energy conversion system is simulated to illustrate the design of this DOBUC and the corresponding performance. [ABSTRACT FROM AUTHOR]

This study investigates the influence of tip speed ratio (TSR) as maximum power point tracking (MPPT) technique on energy conversion for wind-powered electric vehicles (EVs) charging stations. The data for 14 different models of (EVs) as well as the energy demand profile for El Sherouk city in new Cairo, Egypt, is used in the study. Those vehicles represent the models that are most likely to be used according to the nature of the Egyptian market from economic and technological concerns. This includes range, battery capacity, battery technology and charging methods. charging can be in the form of fast DC, three phases which are suitable for commercial charging stations or a single phase charging suitable for residential use. A simulation is done using MATLAB/Simulink for a wind turbine Permanent Magnet Synchronous Generator (PMSG) system including TSR MPPT algorithm. The energy output is compared with and without implementing the MPPT algorithms to measure the difference in energy. The system simulation optimized by the TSR MPPT algorithm shows an increase in the energy yield by 41.68%. The economic analysis showed a 30% reduction in the levelized cost of energy while utilizing the TSR concerning a bare system without an MPPT algorithm. [ABSTRACT FROM AUTHOR]

Summary: In this study, an optimal double frequency second order generalized integrator (DFSOGI) based grid side converter control (GSC) is used for monitoring active power injection from the DFIG wind energy system as well as improving power quality at utility grid terminals. The reference DC voltage is adapted to variations in voltage at the point of common coupling (PCC) that reduces the burden on the converter switches and switching losses. In addition, an intelligent control technique based on white shark optimization algorithm (WSO) is endorsed, where an objective problem is formulated to obtain the desired parameters of the controller. Finally, time‐domain simulations are conducted in MATLAB environment that demonstrate the validity of the implemented control over various operating conditions. To affirm the adequacy of the proposed control strategy, the response of DC link voltage obtained through optimal tuning is compared to the conventional one. The proposed WSO tuning outperforms traditional manual tuning pertaining to enhancing the overall performance of the DFIG system. The designed WSO gains exhibit better steady‐state and transient performance including settling time, steady‐state error, and peak of over amplitude and harmonic distortion. The grid currents' total harmonic distortion (THD) is within 5% that meets specified IEEE‐519 standard. [ABSTRACT FROM AUTHOR]

In the field of optimizing wind system control approaches and enhancing the quality of electricity generated on the grid, this research makes a fresh addition. The Sliding Mode Control (SMC) technique produces some fairly intriguing outcomes, but it has a severe flaw in the oscillations (phenomenon of reluctance: chattering) that diminish the system's efficiency. In this paper, an AST (adaptive super twisting) approach is proposed to control the wind energy conversion system of the permanent magnet synchronous generator (PMSG), which is connected to the electrical system via two converters (grid-side and machine-side) and a capacitor serves as a DC link between them. This research seeks to regulate the generator and grid-side converter to monitor the wind rate reference given by the MPPT technique in order to eliminate the occurrence of the chattering phenomenon. With the help of this approach, precision and stability flaws will be resolved, and the wind system will perform significantly better in terms of productivity. To evaluate the performance of each control in terms of reference tracking, response time, stability, and the quality of the signal sent to the network under different wind conditions, a detailed description of the individual controls is given, preceded by a simulation in the Matlab/Simulink environment. The simulation study validates the control method and demonstrates that the AST control based on the Lyapunov stability theory provides excellent THD and power factor results. This work is completed by a comparative analysis of the other commands to identify the effect on the PMSG wind energy conversion system. [ABSTRACT FROM AUTHOR]

This article proposes an approach and develops an appropriate method of applying linear non-equilibrium thermodynamics to analyze energy processes, in particular using the example of the wind energy conversion system (WECS) with a directly connected vertical axis wind turbine (VAWT) and vector-controlled permanent magnet synchronous generator (PMSG). The main steps of the proposed approach are the description of the component subsystems as universal linear or linearized energy converters (ECs), which are characterized by several dimensionless parameters, the main one of which is the degree of coupling between their input and output. According to their value, as well as justified efficiency criteria, the optimal operating points of each ECs can be easily found. Such an approach makes it possible to abstract from physical laws of a different nature and equally assess the work of each of the subsystems. The next step is a connection of the received ECs. As shown in the paper, for the most common cascade connection of ECs, there are the best conditions for their connection, under which the newly formed equivalent EC can have maximum efficiency. This opens up an opportunity to analyze the influence of already real parameters of cascaded interconnected subsystems on the quality of their connection and justify specific solutions that would not have been seen without this approach. For example, in this study, from all parameters of the PMSG, only the selection of the optimal rated inductance of the armature winding made it possible to improve the quality of the connection of the PMSG with a specific VAWT and approximate the efficiency of the entire WECS to the maximum possible, especially in medium and high winds. [ABSTRACT FROM AUTHOR]

In this study, the experimental implementation of a Hybrid Controller (HC) for a Wind Turbine Emulator (WTE) is presented. Conventionally, the speed control of a WTE is based on two Proportional Integral (PI) controllers used for the outer (speed) loop and inner (torque) loop of a DC motor drive. However, based on the extensive literature survey, with the PI controllers alone, significant overshoot and substantial settling time in the speed response are unavoidable. The overshoot cannot be completely removed without sacrificing speediness. To eliminate the overshoot and concurrently improve the settling time, an HC, combination of Adaptive Neuro-Fuzzy Inference System (ANFIS) and PI controller for the outer and inner loops, respectively, is proposed, designed, implemented and analyzed. The actual wind turbine is emulated using a 2-quadrant DC motor drive based on DS1104 R&D controller board from dSPACE. These two control schemes, namely PI (both controllers are PI), and HC (PI controller for inner loop and ANFIS controller for outer loop) for the WTE are extensively simulated based on the small-scale wind turbine model and eventually implemented using a small-scale laboratory set-up. When implemented in the WTE, with a step-change in wind speed, the hybrid control scheme produces a better result. It is found out the Root Mean Square Error (RMSE) for the WTE rotor speed of the HC is 0.495, which is lower compared to PI control scheme RMSE of 0.7273. Finally, to verify the validity of the WTE based on HC, a random wind speed with wind turbine parameters extracted from the actual wind turbine is applied. The results indicated that the WTE perfectly emulated the wind turbine rotor speed with an RMSE of 0.5004.

In this paper, a wind energy conversion system (WECS) is presented for the electrification of rural areas with wind energy availability. A three-phase AC-DC converter based on a bridgeless Cuk converter is used for power extraction from the permanent magnet synchronous generator (PMSG). The bridgeless topology enables the elimination of the front-end diode bridge rectifier (DBR). Moreover, the converter has fewer components, simple control, and high efficiency, making it suitable for a small-scale WECS. A squirrel cage induction motor (SCIM) is used to emulate a MOD-2 wind turbine to implement the PMSG-based WECS. A direct-drive eight-pole PMSG is used in this study; thus, a low-input-voltage system is designed. The converter is designed to operate in the discontinuous inductor current mode (DICM) for inherent power factor correction (PFC) and the maximum power point tracking (MPPT) is achieved through the tip-speed ratio (TSR) following. The performance of the developed system is analyzed through simulation, and a 500 W hardware prototype is developed and tested in different wind speed conditions.

Direct power smoothing control methods relying on the wind turbine itself have been widely studied to improve wind turbines’ output power quality, and the DC-link voltage control based on the capacitor of the wind power converter is one of them. In this paper, the principle of DC-link capacitor voltage control is studied at first, then an improved time interval DC-link voltage control strategy on the basis of a low-pass filter (LPF) is proposed and compared with existing DC-link voltage power smoothing controls. To further improve the power smoothing effect, the fuzzy logic control is used to adjust the time constant of LPF, and the maximum time constant in the fuzzy logic control is determined through convolution calculation. For the sake of ensuring the system stability, the transfer function of proposed DC-link voltage control is derived to determine proper parameters of voltage loop. The proposed fuzzy logic-based DC-link power smoothing strategy is verified through effective simulation results of the permanent magnet synchronous generator wind energy conversion system (PMSG-WECS).

Summary: An advanced topology comprising a wind‐turbine driven synchronous generator (SG) and solar photovoltaic (PV) array to address the power quality (PQ) concerns and the uncertainty in renewable energy generation is proposed in this paper. The fluctuations in wind speed and insolation are soaked up by utilizing successively interfaced power electronic converters (PECs), namely, SG side converter (SGC) and utility grid side converter (UGC) integrated with a DC link capacitor and a PV array. SGC is controlled by estimating the rotor position from the stator voltage and current measurement data and maintains unity power factor (UPF) at stator terminals. UGC is controlled by employing filtered X least mean fourth (FXLMF) control, which ensures superior convergence performance and reduced computational complexity. Besides, it performs operations like reactive power compensation, enhancement of PQ, load and power balancing during steady‐state and dynamic conditions. The notion of optimal fuzzy reasoning is instilled which generates a fuzzy scheme with inherent optimal‐tuning characteristics to bring about considerable improvement in system performance. A water cycle algorithm (WCA) tuned fuzzy logic controller (FLC) is employed for dynamic stability enhancement leading to the generation of accurate loss component, iloss, which bolsters the ability of VSC to accurately extricate weight signals and the fundamental load current component. This improves regulation of DC link voltage during dynamic load, insolation and wind conditions. The veracity of the proposed model is verified under wind gusts and the bell‐shaped irradiance curve. Extensive simulation results obtained in MATLAB corroborate the efficacy of the system. [ABSTRACT FROM AUTHOR]

In this article, a voltage-fed isolated matrix-type ac/dc converter (VF-MC) is proposed for wind energy conversion system (WECS). Instead of the line-frequency transformer, the high-frequency transformer (HFT) is used for isolation between the generator and the grid. The direct matrix converter (MC) is employed to connect the wind power generator and the HFT, and the intermediate dc capacitors are saved in the ac/ac conversion. Moreover, the proposed VF-MC can work without use of filter capacitors on generator side, and enable more compact size. The dedicated space-vector-modulation scheme and commutation method are proposed for safe operation of the MC. The voltage spikes due to the leakage inductance of HFT are thus reduced and the additional snubber circuit is avoided in the proposed system. A 1-kW laboratory prototype of the proposed VF-MC-based WECS is built to verify the effectiveness of the system experimentally. [ABSTRACT FROM AUTHOR]

As theincrease of wind power penetration, the fluctuations of wind power results in serious power system frequency turbulences. This article proposes a low-pass virtual filter (VF) for wind energy conversion systems (WECSs) to smoothen output power. First, a linearized model is established for a WECS. Then, a low-pass VF is derived for the active power control loop in WECS to modulate the kinetic energy stored in rotating mass for output smoothing. The principle is to modify the traditional wind power controller to emulate a physical energy storage system controlled as a low-pass filter to smooth the wind power output. The proposed low-pass VF does not need the physical deployment of energy storage system but still can filter the high-frequency fluctuations in the output wind power. Furthermore, in order to ensure operation stability of the wind turbine (WT), a stability-constrained coefficient is determined according to the proposed stability criteria to ensure the stability of WTs. Simulation and experiment results verify the effectiveness of the proposed VF in WECS for output wind power fluctuation reduction and the stability-constrained coefficient for stability ensuring. [ABSTRACT FROM AUTHOR]

This paper presents the modeling of wind energy systems using MATLAB Simulink. The model considers the MPPT (Maximum Power Point Tracking) technique to track the maximum power that could be extracted from the wind energy. The main contribution of our work lines in the choice of the Wind Energy Conversion System (WECS) components and the suitable MPPT technique. An innovating maximum MPPT technique is proposed. This technique combines the advantages of an ameliorated Perturb & Observe (P&O) control algorithm and the speed of Optimal Relationship Based (ORB) control algorithm to allow the MPPT controller output (duty cycle) adjusts the voltage input of a Buck-Boost converter to track the maximum power point. It searches for the system optimum relationship for maximum power point tracking and then controls the system based on this relationship. The main advantage of the proposed technique is that it does not require an anemometer or preknowledge of a system, but has an accurate and fast response to wind speed fluctuations. The MATLAB/Simulink simulation results show that the developed model components choice complies with cost and reliability constraints and confirm the validity and performance of the proposed control algorithm. [ABSTRACT FROM AUTHOR]

The paper deals with the performance checking of an optimally designed LCL-filter connected along the grid-side converter (GSC) in a doubly fed induction generator (DFIG) based wind energy conversion system (WECS) in attenuating harmonics. A repetitive approach is required for designing the parameters of the LCL-filter. The reasons being the explicitness of design parameters and design requirements of the proposed filter like IEEE-519 Std. for harmonic current attenuation, maximum voltage difference allowed in between two sides of the filter to limit switching losses, and limit of reactive power compensation. The proposed filter is compared with the conventional LCL-filter. Based on the proposed method, a minimal inductance and optimal capacitance-based filter is obtained in this paper which is validated using a 2.2 kW DFIG based WECS. Comparative stability analysis of DFIG system with and without proposed filter is performed using small signal stability analysis. The system under study is simulated using MATLAB/Simulink and OPAL-RT 4510, simultaneously. Simulation results validates the effective use of proposed filter design method into DFIG system in terms of harmonic attenuation, total harmonic distortion and reactive power compensation.

The adoption of renewable energy sources, particularly wind energy, has seen remarkable growth in recent years. Wind energy generation requires efficient and reliable generators that can convert wind energy into usable electrical energy. Switched Reluctance Generators (SRGs) have been gaining popularity in wind energy applications due to their high efficiency, reliability, and low maintenance requirements. The multiphase switched reluctance generators are used especially in wind power plants due to their ability to operate in variable speed ranges. In this paper, a MATLAB/SIMULINK based model of Switched Reluctance Generator (SRG) is presented. The obtained results show good agreement under different operating conditions. The obtained results (current, voltage, torque, speed, flux, and angle of generator) are shown in graphs.

In this paper, a novel robust fault-tolerant control scheme based on event-triggered communication mechanism for a variable-speed wind energy conversion system (WECS) with sensor and actuator failures is proposed. The nonlinear WECS with event-triggered mechanism is modeled based on the Takagi–Sugeno (T–S) fuzzy model. By Lyapunov stability theory, the parameter expression of the proposed robust fault-tolerant controller with event-triggered mechanisms is proposed based on a feasible solution of linear matrix inequalities. Compared with the existing WECS fault-tolerant control methods, the proposed scheme significantly reduces the pressure of network packet transmission and improves the robustness and reliability of the WECS. Considering a doubly-fed variable speed constant frequency wind turbine, the event- triggered mechanism based fault-tolerant control for WECS is analyzed considering system model uncertainty. Numerical simulation results demonstrate that the proposed scheme is feasible and effective.

We present the ferroresonance overvoltage mitigation concerning the power systems of the grid-connected wind energy conversion systems (WECSs). WECS is considered based on a doubly-fed induction generator (DFIG). Ferroreso-nance overvoltage associated with a single-pole outage of the line breaker is mitigated by fast regulating the reactive power using the static compensator (STATCOM). STATCOM controller is introduced, in which two incorporated proportional-inte-gral (PI) controllers are optimally tuned using a modified flower pollination algorithm (MFPA) as an optimization technique. To show the capability of the proposed STATCOM controller in mitigating the ferroresonance overvoltage, two test cases are introduced, which are based on the interconnection status of the power transformer used with the grid-connected DFIGs. The results show that the ferroresonance disturbance can occur for the power transformers installed in the wind farms although the transformer terminals are interconnected, and neither side of the transformer is isolated. Furthermore, as a mitigation method of ferroresonance overvoltage, the proposed STATCOM controller succeeds in improving the system voltage profile and speed profile of the wind turbine as well as protecting the system components against the ferroresonance overvoltage.

In this paper, a control model based on hybrid algorithm is proposed to improve LVRT capability of the DFIG system. The proposed hybrid system is joined performance of fertile field algorithm (FFA) and momentum search algorithm (MSA) with adaptive neuro-fuzzy inference system (ANFIS). The searching behavior of FFA is enhanced by the updating behavior of MSA. Hence, commonly the proposed system is known FAMSANFIS technique. The purpose of the proposed control system makes sure LVRT capacity on DFIG-based wind energy conversion system under fault and voltage dip conditions. Here, the FFA–MSA methodology is used as the offline way to recognize the optimal solutions as obtainable search space. The FFA–MSA system, multiple parameters are measured to be related with LVRT, as voltage, real and reactive power, and current, correspondingly. The objective function solved using the FFA–MSA system is characterized. In light of the achieved data set, ANFIS performs and forecasts the better probable control signals from machine-side and network-side converter. Through fault conditions, the proposed system regulates system and voltage instability problem, respectively. The LVRT capability of the DFIG system is enhanced and, in addition, the power quality is improved through the aid of proposed system. The proposed control procedure is implemented on MATLAB/Simulink framework, and performances are assessed using the comparison analysis with existing techniques. [ABSTRACT FROM AUTHOR]

As the wind energy is progressively pursued to supplement conventional power generation, the stochastic wind behavior considerably deteriorates power quality (PQ) and stability of the connected grid. This article is attributed to the comprehensive control design of the grid-integrated doubly fed induction generator (DFIG) wind energy system that aims to address encountered wind variability and PQ intricacies. Battery energy storage with bidirectional dc–dc converter control is assimilated at the dc-link of the DFIG that regulates the dc-link voltage to mitigate the wind power fluctuations in specified grid power modes. A higher order adaptive control for grid-interfaced converter accurately computes desired weights of various components to exercise accurate power balance and PQ control. Moreover, a novel Jaya particle swarm optimization algorithm is adopted for the optimal tuning of wind maximum power point tracking and the dc-link voltage PI controller parameters that significantly improves steady-state and dynamic responses of both the controllers. The rotor speed converges faster with precise reference tracking that leads to almost zero steady-state error using optimized PI controller gains. Along with the attenuated initial overshoot and fast settling time during sudden large step wind speed change, the dc-link voltage also characterizes superior response with optimal tuning during load unbalance and abnormal grid voltage conditions. The presented control strategy analyzes the capability of DFIG system under variable wind-speed changes, specified grid power modes, load changes, and other grid disturbances. The satisfactory system response is endorsed through experimental results conducted on a laboratory prototype. [ABSTRACT FROM AUTHOR]

Wind turbines driven by permanent magnet synchronous generators (PMSG) are widely used in the present utility industry because of their better efficiency in terms of energy generation and design simplicity. However, the performance of such a system is greatly reduced when subjected to the intermittency of a wind speed or sudden wind gust. An efficient approach was proposed by integrating the neural network (NN)-based wind turbine model with a PMSG system to accurately and efficiently estimate the maximum power and optimal turbine speed to drive the PMSG rotor. This strategy employs the speed control method for the PMSG system, where the proportional-integral controller is feedback with the error signal of the PMSG output rotor speed and the reference speed generated by the NN-based wind turbine model. The performance of the wind turbine NN-based PMSG model was investigated using both MATLAB and SIMULINK tools. The robustness of the control strategy is verified by subjecting the model to the wind speed ranging from 4 to 13 m/s to obtain the maximum power with an error as low as 0.0025%. Further, a case study was performed by using the real-time wind speed data for Hafar Al-Batin, KSA and the potential for wind power generation is explored. The maximum power and optimum reference speed to drive the PMSG rotor was estimated using the proposed model for this location and compared with the theoretically calculated maximum power and optimum reference speed with an error of less than 0.27%. [ABSTRACT FROM AUTHOR]

As the finite nature of non-renewable energy resources is realised and climate change concerns become more prevalent, the need to shift to more sustainable forms of energy such as the adoption of renewable energy has seen an increase. More specifically, wind energy conversion systems (WECS) have become increasingly important as a contribution to grid frequency support, to maintain power at the nominal frequency and mitigate power failures or supply shortages against demand. Therefore, limiting deviations in frequency is imperative and, thus, the control methods of WECS are called to be investigated. The systematic literature review methodology was used and aimed at investigating these control methods used by WECS, more specifically variable-speed wind turbines (VSWT), in supporting grid frequency as well as the limitations of such methods. The paper identifies these to be de-loading, energy storage systems and emulated inertial response. Further classification of these is presented regarding these control methods, which are supported by literature within period of 2015–2022. The literature indicated a persistent interest in this field; however, a few limitations of VSWTS were identified. The emulated inertial response, specifically using a droop control-based frequency support scheme, was the primary means of providing frequency support. This systematic literature review may be limited by the number of papers selected for the study. Results and conclusions will not only be useful for WECS development but also in assisting with the security of the transmission grid's frequency stability. Future work will focus on further studying the limitations of WECS providing frequency support. [ABSTRACT FROM AUTHOR]

The direct-drive permanent-magnet synchronous generator (PMSG) based wind energy conversion system (WECS) with a soft drivetrain shaft is vulnerable to torsional oscillation when it participates in power oscillation damping (POD) services for the AC grid. This paper investigates three possible scenarios of incorporating both torsional oscillation damping (TOD) and POD controllers into PMSG-based WECS. A model of a PMSG-based offshore wind farm (OWF) connected to the IEEE 39-bus AC grid is developed and utilized to analyze the stability and dynamic performances of the WECS within these three scenarios. Comprehensive modal analysis is carried out to analyze the interaction between the torsional and power oscillations, and to tune the TOD and POD controllers to damp these oscillations simultaneously in each scenario. Furthermore, the dynamic performances of the PMSG-based WECS within these scenarios are evaluated through time-domain simulations. Then an optimal scenario for PMSG-based WECS to damp both oscillation types with close frequencies is identified, which is modulating the DC-link voltage for the TOD and the grid-side active power for the POD. This result can provide useful guidance for the future industrial application of the TOD and POD control in the PMSG-based WECS. [ABSTRACT FROM AUTHOR]