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1.
PLoS One ; 19(6): e0305272, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38941302

RESUMO

This article represents a novel study of the design and analysis of a wind turbine system that includes a line-side permanent magnet synchronous generator (PMSG) with an ultra-step-up DC-DC converter for voltage regulation. Integrating renewable energy sources such as wind power into the grid requires efficient and reliable power conversion systems to handle fluctuating power and ensure a stable power supply. The wind turbine system utilizes a PMSG, which offers several advantages over traditional induction generators, including higher efficiency, reduced maintenance, and better power quality. The line-side configuration allows for increased control and flexibility, allowing the system to respond dynamically to grid conditions. This wind turbine system involves the integration of a grid-side PMSG-fed DC-DC converter between the PMSG and the grid. The converter enables a seamless flow of electricity between the wind turbine and the grid. By actively controlling the intermediate circuit voltage, the converter efficiently regulates the output voltage of the wind turbine and thus enables constant power generation regardless of fluctuating wind speeds. The simulation outcomes illustrate the efficacy of the proposed system in achieving voltage regulation and seamless integration with the grid. Performance is evaluated under various operating conditions and compared to conventional wind turbines.


Assuntos
Fontes de Energia Elétrica , Eletricidade , Vento , Energia Renovável , Desenho de Equipamento
2.
Sci Rep ; 14(1): 12920, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38839866

RESUMO

The parameter extraction process for PV models poses a complex nonlinear and multi-model optimization challenge. Accurately estimating these parameters is crucial for optimizing the efficiency of PV systems. To address this, the paper introduces the Adaptive Rao Dichotomy Method (ARDM) which leverages the adaptive characteristics of the Rao algorithm and the Dichotomy Technique. ARDM is compared with the several recent optimization techniques, including the tuna swarm optimizer, African vulture's optimizer, and teaching-learning-based optimizer. Statistical analyses and experimental results demonstrate the ARDM's superior performance in the parameter extraction for the various PV models, such as RTC France and PWP 201 polycrystalline, utilizing manufacturer-provided datasheets. Comparisons with competing techniques further underscore ARDM dominance. Simulation results highlight ARDM quick processing time, steady convergence, and consistently high accuracy in delivering optimal solutions.

3.
Heliyon ; 10(10): e30669, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38770320

RESUMO

Voltage and reactive power regulation in a deregulated microgrid can be achieved by strategically placing the Static Synchronous Compensator (STATCOM) in coordination with other renewable energy sources, thus ensuring high-end stability and independent control. STATCOM plays a crucial role in effectively addressing power quality issues such as voltage fluctuation and reactive power imbalances caused by the intermittent nature of wind energy conversion systems. To successfully integrate STATCOM into the existing system, it is essential that the control system employed for STATCOM coordination aligns with the Doubly-Fed Induction Generator (DFIG) controller within the microgrid. Therefore, an efficient control algorithm is required in the microgrid, capable of coordinating with the DFIG controller while maintaining system stability. The utilization of a Genetic Algorithm (GA) in calibrating the Restricted Boltzmannn Machine (RBM) can streamline the process of determining optimal hyperparameters for specific tasks, eliminating the need for computationally intensive and time-consuming grid searches or manual tuning. This approach is particularly advantageous when dealing with large datasets within short time durations. In this research, a Simulink model comprising a DFIG-based microgrid and STATCOM has been developed to demonstrate the effectiveness of the proposed control system using RBM in managing STATCOM and facilitating microgrid operations.

4.
PLoS One ; 19(5): e0301522, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38776325

RESUMO

The design of a power electronic interface for high voltage difference DC buses is a key aspect in DC microgrid applications. A multi-port non isolated interleaved high-voltage gain bidirectional converter, which facilitates bidirectional power transfer and islanded operation in a DC microgrid, is presented in this paper. The forward high-voltage transfer ratio is achieved using a voltage multiplier circuit, and the high-gain step-down power conversion is performed using a resonant power module. A novel power transfer selection algorithm is proposed to control power flow among the interfaces of the RES, ESS, and DC grid converters, which utilizes the net power difference as the basis for switching the converter. The proposed converter is simulated for a 24 V PV source, 12 V battery, and 400 V DC grid interface using MATLAB/SIMULINK. A 200 W hardware prototype is implemented. The simulation results for voltages, currents, and power flow among RES, ESS, and microgrid DC bus proved an excellent voltage regulation, efficient power conversion, and a feasible duty cycle range with high voltage gain. These observations are validated through equivalent experimental results. A comparison is made regarding achieved gain, component sizing, achievable power transfer modes, efficiency, and control complexity with existing converters for DC microgrid applications. The presented topology proved to be a better interface with multiple-mode support with high efficiency.


Assuntos
Fontes de Energia Elétrica , Algoritmos , Desenho de Equipamento , Simulação por Computador
5.
Sci Rep ; 14(1): 5664, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38453951

RESUMO

The paper proposes a nonlinear controller called dual super-twisting sliding mode command (DSTSMC) for controlling and regulating the rotor side converter (RSC) of multi-rotor wind power systems that use doubly-fed induction generators. It was proposed that this controller be developed as an alternative to the direct power control (DPC), which makes use of a pulse width modulation (PWM) strategy to regulate the RSC's functioning. Overcoming the power/current quality issue with the proposed technique (DPC-DSTSMC-PWM) is characterized by great robustness and excellent performance. The designed strategy was contrasted with the standard method of control and other methods already in use. So, the unique proposed control strategy's robustness, performance, efficiency, and efficacy in enhancing system characteristics were tested and validated in Matlab/Simulink. In both tests, the proposed method resulted in significant improvements, reducing active power ripples by 83.33%, 57.14%, and 48.57% in the proposed tests. When compared with the traditional regulation method, the reduction rates of reactive power ripples are 64.06%, 52.47%, and 68.7% in the tests. However, in contrast to the conventional method, the proposed tests showed a decrease of between 72.46%, 50%, and 76.22% in the value of total harmonic distortion (THD) of the provided currents. These ratios show how effective the proposed plan is in ameliorating and enhancing aspects of the energy system.

6.
Heliyon ; 10(5): e27312, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38495137

RESUMO

In this work, the operation of photovoltaic system, wind turbine driven doubly fed induction generator along with battery has been observed. Also, a searching space minimization-based artificial bee colony scheme is developed for tracking the maximum power in a doubly fed induction generator-based system. To track maximum power in solar systems, an improved adaptive reference voltage approach has been presented. Several conventional and optimization-based techniques are used by DFIG and photovoltaic systems to get around the non-linearity features in the output parameters. Regarding DFIG, the artificial bee colony method based on searching space minimization can be used to solve the shortcomings of the perturb and observe algorithm. Because of its weather-sensitive nature, it can withstand sudden changes in wind speed. The suggested searching space minimization based artificial bee colony strategy uses a mechanism for determining the range of optimal rotor speed in order to track the maximum power point more quickly. The maximum power point tracking performance of the adaptive reference voltage technique is superior to that of current perturb and observed-based systems. However, a huge processing memory is required in order to track the maximum possible power point. This paper proposes an enhanced maximum power point tracking technique based on adaptive reference voltage that does not require a memory unit. Additionally, despite sudden changes in irradiation conditions, improved adaptive reference voltage can drift-free and reliably monitor the maximum power point. The new adaptive reference voltage technique uses temperature and radiation sensors to identify the region nearest to the maximum power point. This helps the system respond more quickly. The proposed system with searching space minimization based artificial bee colony and improved adaptive reference voltage schemes displays lower inter-harmonic content in grid current compared to perturb and observe scheme. The proposed scheme has been implemented in MATLAB & simulink atmosphere and OPAL-RT displayed satisfactory results.

7.
Sci Rep ; 14(1): 3248, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38332236

RESUMO

This work emphasizes the development and examination of a Hybrid Luo Converter integrated with a unified Maximum Power Point Tracking (MPPT) for both grid and independent hybrid systems. The primary objectives of this hybrid system are to efficiently harness power from intermittent and variable renewable sources while elevating low-voltage energy inputs to utility-grade levels. Unlike previous studies employing specific MPPT algorithms for solar and wind sources, this work aims to simplify the control system by utilizing a unified MPPT controller. This research also introduces a novel approach involving dual-lift hybrid Luo converters to create hybrid systems, operating exclusively or concurrently based on the availability of renewable resources. To maximize power generation from all renewable sources, a unified MPPT algorithm is developed. The hybrid system, incorporates 500 W wind and 560 W PV systems, the innovative Luo converter, and the unified MPPT controller. A comprehensive comparative analysis is presented, comparing the hybrid system's performance with that of traditional control algorithms, such as the Perturb & Observe, and Radial Basis Function Network controllers. The successful prototype of the converter validates the practicality of the proposed approach.

8.
Sci Rep ; 14(1): 3342, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38336945

RESUMO

As of now, there are multiple types of renewable energy sources available in nature which are hydro, wind, tidal, and solar. Among all of that the solar energy source is used in many applications because of its features are low maitainence cost, less human power for handling, a clean source, more availability in nature, and reduced carbon emissions. However, the disadvantages of solar networks are continuously depending on the weather conditions, high complexity of the solar energy storage, and lots of installation place is required. So, in this work, the Proton Exchange Membrane Fuel Stack (PEMFS) is utilized for supplying the power to the local consumers. The merits of this fuel stack are high power density, ability to work at very less temperature values, efficient heat maintenance, and water management. Also, this fuel stack gives a quick startup response. The only demerit of PEMFS is excessive current production, plus very less output voltage. To optimize the current supply of the fuel stack, a Wide Input Operation Single Switch Boost Converter (WIOSSBC) circuit is placed across the fuel stack output to improve the load voltage profile. The advantages of the WIOSSBC are less current ripples, uniform voltage supply, plus good voltage conversion ratio. Another issue of the fuel stack is nonlinear power production. To linearize the issue of fuel stack, the Grey Wolf Algorithm Dependent Fuzzy Logic Methodology (GWADFLM) is introduced in this article for maintaining the operating point of the fuel cell near to Maximum Power Point (MPP) place. The entire system is investigated by utilizing the MATLAB software.

9.
Heliyon ; 9(11): e21488, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38034628

RESUMO

The heliostat field layout in a central receiver solar thermal power plant has significant optical losses that can ultimately affect the overall output power of the plant. In this paper, an optimized heliostat field layout based on annual efficiency and power of 50 MW for the local coordinates of Quetta, Pakistan, is proposed. The performance of two different heliostat field layouts such as radial staggered and Fermat's spiral distribution are evaluated and different design points in a year are considered for the analysis. The field layouts are then optimized using a rejection sampling based Genetic Algorithm (GA). It considers the output power and mean overall efficiency for vernal equinox, summer solstice, autumnal equinox, and winter solstice as objective functions. The GA optimizes the heliostat field parameters, namely, security distance (DS), tower height (TH), heliostat width to length ratio (WR), and the length of heliostats (LH). The study system was developed in MATLAB for validation. It was observed that for the radial staggered layout, the number of heliostats decreased by 364 and the efficiency was improved by 8.52 % using GA optimization relative to unoptimized results field layout. The annual efficiency for Fermat's spiral configuration was improved by 14.62 % and correspondingly, the number of heliostats decreased by 434.

10.
Sci Rep ; 13(1): 17534, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37845297

RESUMO

The power grid faults study is crucial for maintaining grid reliability and stability. Understanding these faults enables rapid detection, prevention, and mitigation, ensuring uninterrupted electricity supply, safeguarding equipment, and preventing potential cascading failures, ultimately supporting the efficient functioning of modern society. This paper delves into the intricate challenge of ensuring the robust operation of wind turbines (WTs) in the face of fault conditions, a matter of substantial concern for power system experts. To navigate this challenge effectively, the implementation of symmetrical fault ride-through (SFRT) and asymmetrical fault ride-through (AFRT) control techniques becomes imperative, as these techniques play a pivotal role in upholding the stability and dependability of the power system during adverse scenarios. This study addresses this formidable challenge by introducing an innovative SFRT-AFRT control methodology based on rotor components optimization called RCO tailored for the rotor side converter (RSC) within a doubly-fed induction generator (DFIG) utilized in wind turbine systems. The proposed control strategy encompasses a two-fold approach: firstly, the attenuation of both positive and negative components is achieved through the strategic application of boundary constraints and the establishment of reference values. Subsequently, the optimization of the control characteristic '[Formula: see text]' is accomplished through the utilization of a particle swarm optimization (PSO) algorithm integrated within an optimization loop. This intricate interplay of mechanisms aims to optimize the performance of the RSC under fault conditions. To measure the efficacy of the proposed control technique, a comparative analysis is conducted. Fractional-order (FO) proportional-integral-derivative (PID) controllers are employed as an additional method to complement the novel approach. By systematically juxtaposing the performance of the proposed SFRT-AFRT control technique with the FO-PID controllers, a comprehensive evaluation of the proposed approach's effectiveness is attained. This comparative assessment lends valuable insights into the potential advantages and limitations of the novel control technique, thereby contributing to the advancement of fault mitigation strategies in WT systems. Finally, the paper highlights the economic viability of the proposed control method, suggesting its suitability for addressing broader power network issues, such as power quality, in future wind farm research.

11.
Arab J Urol ; 20(4): 189-194, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36353469

RESUMO

Objective: To compare outcomes of low-intensity extracorporeal shock wave therapy (LIESWT) versus 20 mg of Tadalafil in Erectile dysfunction (ED) patients. Materials and Methods: We performed a prospective study of 51 men with ED. Twenty-five were in the LIESWT group and 26 in the Tadalafil group. Patients in the LIESWT group received 6 sessions (2 per week) with an average of 6,000 shocks per session with the PiezoWave2 unit. Other patients self-administered Tadalafil on demand. The outcomes were assessed using the International Index of Erectile Function (IIEF-5) score, Erection Hardness Score (EHS) and Self-Esteem And Relationship (SEAR) questionnaire before, at 6 and 12 weeks after treatment. Treatment-related side effects and costs were recorded too. Results: The mean age in the LIESWT group was 43.7 years old, and in the Tadalafil group was 47 years old. After the 6 and 12-week follow-ups, both groups showed significant improvement when comparing the baseline values to the follow-up variables for all IIEF-5, EHS, and SEAR (P < 0.05). There was a notable statistical difference between the two groups regarding the side effects, as the shockwave group was with mild side effects (8%), while the Tadalafil group (44%) of patients had side effects (p < 0.05). This cost difference is statistically significant (p < 0.001). LIESWT is more costly compared to Tadalafil. Conclusion: LIESWT has a comparable short-term therapeutic efficacy with higher safety outcomes than on-demand 20 mg of Tadalafil for ED patients.

12.
Sensors (Basel) ; 22(20)2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36298266

RESUMO

The number of unsecured and portable Internet of Things (IoT) devices in the smart industry is growing exponentially. A diversity of centralized and distributed platforms have been implemented to defend against security attacks; however, these platforms are insecure because of their low storage capacities, high power utilization, single node failure, underutilized resources, and high end-to-end delay. Blockchain and Software-Defined Networking (SDN) are growing technologies to create a secure system and to ensure safe network connectivity. Blockchain technology offers a strong and trustworthy foundation to deal with threats and problems, including safety, privacy, adaptability, scalability, and security. However, the integration of blockchain with SDN is still in the implementation phase, which provides an efficient resource allocation and reduced latency that can overcome the issues of industrial IoT networks. We propose an energy-efficient blockchain-integrated software-defined networking architecture for Industrial IoT (IIoT) to overcome these challenges. We present a framework for implementing decentralized blockchain integrated with SDN for IIoT applications to achieve efficient energy utilization and cluster-head selection. Additionally, the blockchain-enabled distributed ledger ensures data consistency throughout the SDN controller network and keeps a record of the nodes enforced in the controller. The simulation result shows that the proposed model provides the best energy consumption, end-to-end latency, and overall throughput compared to the existing works.

13.
Asian J Androl ; 24(2): 167-170, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34213492

RESUMO

Penile prosthetic implantation represents a cornerstone for patients with organic erectile dysfunction (ED) that is refractory, unsatisfactory, or contra-indicated for other approved medical or mechanical options. In this study, we introduce the "Ghattas technique," wherein we constructed a polypropylene mesh sheath that surrounds and is fixed to a 13-mm malleable prosthesis cylinder, which can increase the cylinder diameter for cases that need a larger prosthesis. All patients underwent preoperative evaluation and completed the five-item International Index of Erectile Function questionnaire (IIEF-5). Postoperative outcomes were evaluated by IIEF-5 and Erectile Dysfunction Inventory of Treatment Satisfaction (EDITS) questionnaires at final follow-up. The mean age of the 23 included patients was 57.9 (standard deviation [s.d.]: 11.4) years and the mean duration of ED was 8.5 (s.d.: 7.9) years. Erection improvement was determined by comparing mean preoperative and postoperative IIEF-5 scores (8.3 [s.d.: 3.9] vs 24.6 [s.d.: 0.6], P < 0.001). High treatment satisfaction was determined according to a mean EDITS score of 94.9 (s.d.: 9.9). The proposed Ghattas technique was safe and effective in our patients, and provides opportunity for cases that need a diameter larger than 13 mm. Further studies are needed to confirm these results.


Assuntos
Disfunção Erétil , Prótese de Pênis , Criança , Disfunção Erétil/cirurgia , Humanos , Masculino , Satisfação do Paciente , Telas Cirúrgicas , Inquéritos e Questionários , Resultado do Tratamento
14.
Clin Pract ; 2(2): e42, 2012 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-24765441

RESUMO

This case report describes a 32-year-old male who presented to an emergency department with severe chest pain and a history of cough, fever, night sweats, loss of appetite and weight. Chest radiography revealed a left upper lobe consolidation and multiple compression deformities in the thoracic spine. Magnetic resonance imaging demonstrated significant kyphosis and vertebral plana at two thoracic levels. Anterior compression of the spinal cord and adjacent soft tissue masses were also noted.

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