Types Of Wind Turbines Research Articles

Forecasting Wind Power Generation Using Artificial Neural Network

Today, among renewable energy sources, wind energy is used effectively as a clean and sustainable energy source in electricity generation. The uncertain nature of renewable energy sources and the smart ability of the neural network approach to process complex time series inputs have allowed the use of artificial neural network (ANN) methods in the prediction of renewable energy generation. In this study, the speed and power of wind turbines and electricity generation were estimated from wind speed data using artificial neural networks. In our calculations, the real wind speed data were used in the test phase, and the speed-power data of six different types of wind turbines were used in the training phase. It has been shown that the predictions made by our ANN model from the regression curves of the training, validation, and test data obtained are quite successful and reliable. According to our results, it has been understood that the wind potential of our selected region is good enough and that the electrical energy need for this region can be met from wind energy by using the appropriate wind turbine type, so it is quite appropriate to invest in wind energy.

Evaluation of the Influences of Different Roof Shapes on the Flow Properties and Performance of Small Wind Turbines

Small wind turbines offer a complement to photovoltaic systems and are becoming an interesting solution in the wake of rising energy prices. The measurement results indicate that some locations on and around the building are not suited for installing wind turbines, while others show increased wind potential. Due to limited space, rooftop mounting is an interesting alternative to free mounting on a mast from a technical point of view. For this reason, the influence of roof shapes on the flow on and behind the building was measured and the performance of two different types of small wind turbines was investigated. The turbines assessed in the project are VertikonM with a vertical axis and helix-shaped rotor blades, and Superwind 1250 wind turbine with a horizontal axis and centrifugal force pitch control. The results showed that there is an average increase in wind speed of 0.2 m/s on gable roofs at hub height (7 m). In comparison, there is an increase of 0.4 m/s on flat roofs at hub height (7 m). In relation to the performance of the turbines, high turbulence on the roof seems to cancel out this effect. The performance of the horizontal axis small wind turbine has not increased in comparison with gable roof and free-standing mast. For the vertical-axis turbine, a power increase by a factor of 2.23 was achieved between free-standing mast and gable roof. Vertical wind flow above the gable roof was identified as the main cause for power increase. The experiment was conducted on the Lichtenegg energy research park (Lower Austria) and its results make it possible to better identify all effects that affect the turbine output power.

Improving the oscillating wind turbine model

Disadvantages in the structure of the most common rotary wind generators limit their use. This motivates the development of alternative types of wind turbines, the most promising of which are oscillating wind generators. The object of the study is the structure of an oscillating type wind generator, which provides self-oscillating movement of the blade-wing. The design of the wind generator uses a modified wing shape to provide maximum lift. For this purpose, added elements are the tip and flap, which affect the shape of the wing, its angle of attack, and regulate the direction of the lifting force. The principle of attaching the tip and flap to the wing using spiral springs has been developed. The structure also includes locking magnets that affect the movement of the wing during a turn. The mechanism that drives the self-oscillating mode of operation of the wind turbine was described. This mode occurs under the action of the inertial force of the movement of the wing, the force of elasticity, the repulsive force of the magnets, and the pressure force of the air flow. A computer simulation of the wind generator was carried out using the Ansys CFX software package. The model of the flow around an absolutely rigid body at small values of the Reynolds number was applied. The resulting dynamics of the horizontal movement of the wing of the wind turbine make it possible to use it for energy generation already at a wind speed of 2 m/s. The low cost of the wing and the automatic regulation of its movement make it possible to install many wings to increase the power of the wind generator. Thus, the improved wind turbine is low-cost, harmless to birds, has self-regulation of wing movement and can use the low-speed component of the wind, which significantly expands the geography of its operation. It is possible to transfer the proposed technological solutions for the construction of hydroelectric generators

Assessment of Bach-type internal rotor on the performance of a hybrid wind turbine: effects of attachment angle, tip speed ratio, and free-wind speed

ABSTRACT The application of the Darrieus rotors in regions with lower wind potentials is one of the challenging issues in the operation of this type of vertical axis wind turbine (VAWT). To overcome this problem, various combinations of Darrieus and Savonius rotors, called the hybrid rotor, are proposed, which is one of the attractive subjects among wind turbine researchers. Using the computational fluid dynamics technique (CFD), this study investigates a new combination between the Savonius and Darrieus rotors at which a two-bladed Bach-type rotor is attached inside a two-bladed Darrieus rotor made by NACA 0018. In this way, various attachment angles (α) between the internal and external rotors such as 0°, 45°, and 90° are studied to find the optimal case. Computations are performed for various tip speed ratios (TSR) such as 1.5, 2.5, and 3.5, and free-wind speeds (U∞) of 5 and 10 m/s. The obtained results revealed that the application of a hybrid wind turbine is more beneficial under lower TSR and U∞ values. Additionally, it is demonstrated that the case with α = 90° is the optimal case in TSR = 1.5 and 2.5 providing a maximum 21.43% improvement in comparison to the Darrieus rotor for TSR = 1.5 and U∞ = 5 m/s.

An Enhanced AC Fault Ride through Scheme for Offshore Wind-Based MMC-HVDC System

This study presents an improved, communication-free Fault Ride-Through (FRT) strategy for type-3 and type-4 wind turbine integrated modular multilevel converter-based high-voltage direct current (MMC-HVDC) systems in offshore wind power plants (OWPPs). The research aims to enhance the reliability and resilience of OWPPs by ensuring their connection with AC grids remains intact during and after faults. Simulation results conducted on a 580 kV, 850 MW MMC-HVDC system using PSCAD/EMTDC software v.4.6.2 demonstrate quick post-fault recovery operation and the ability to effectively manage DC link and capacitor voltages within safe limits. Furthermore, the circulating current (CC) and capacitor voltage ripple (CVR) remain within acceptable limits, ensuring safe and reliable operation. The study’s major conclusion is that the proposed FRT strategy effectively mitigates the adverse effects of short circuit faults, such as a rapid rise in DC-link voltage, on the performance of the MMC-HVDC system. By promptly suppressing DC-link overvoltage, the proposed FRT scheme prevents compromising the safe operation of various power electronics equipment. These findings highlight the significance of FRT capability in OWPPs and emphasize the practical applicability of the proposed strategy in enhancing the reliability of offshore wind power generation.

Modification of the Vertical Axis with Variations in the Number of Blades of the Savonius Wind Turbine

The potential wind speed in Indonesia is generally low at 3 m/s to 7 m/s so that this type of vertical axis turbine is considered very suitable for use in wind conditions in Indonesia. There are several types of vertical axis wind turbines. One type of vertical axis wind turbine is the Savonius wind turbine. Many advantages that this type of wind turbine has, such as being able to receive wind from all directions, easy and cheap to manufacture, and can rotate at a fairly low angular speed. This test was carried out to determine the performance of conventional and modified savonius turbines with 2 and 3 blades variables in each turbine blade shape. The form of modification made is by changing the shape of the blade twisting by 45o. The turbine is carried out on a laboratory scale with a wind source using a fan that is directly opposite the turbine. The results showed that the highest turbine power occurred in a modified 2-blade turbine, namely 1.88 Watt with a torque value of 0.04 Nm and a shaft rotation of 450 rpm. The highest rotation value is also obtained by 2 modified blades at a wind speed of 6 m/s producing 896 rpm. However, the highest torque value is obtained by a conventional 2-blade turbine with a value of 0.136 Nm. The highest turbine efficiency in each turbine is obtained by a modified 2 blade turbine with an efficiency value of 36.92% while the highest turbine efficiency for a modified 3 blade turbine reaches 11.69% which is considered less efficient than other turbines.

OPTIMALISASI METODE BLADE TURBIN ANGIN SUMBU HORIZONTAL

The utilization of wind turbines is able to convert wind energy into electrical energy. It is recorded from the DG of NREEC source that Indonesia has a wind energy potential of 60.6 Giga Watt (GW) with a total renewable energy potential of 442GW. One of the most common types of wind turbines is the horizontal axis wind turbine. This study uses a literature study method that aims to compare and summarize data optimizing variations in the number of blades and wind speed on horizontal axis wind turbines from various sources. The results of the study are known that the pinwheel power generated by the rotation of the pinwheel blade produces energy that is converted into electrical energy. The wind speed and blade rotation yield are directly proportional to the energy produced. The greater the wind speed given to the turbine, the higher the rotation. Variations in the number of blades result in variations in rotational properties, since the effect of the ratio of tip speed is inversely proportional to wind speed. The performance of horizontal axis wind turbines can be optimized by applying blade design using chord and twist linearization methods. The greatest efficiency of the counter-rotational horizontal shaft wind turbine is achieved at a blade angle of 10° and a wind speed of 4.03m/s, resulting in a maximum efficiency of up to 71.8%, which is higher than the optimal single-rotor power coefficient of 59%. This means dual-rotor wind turbines are more efficient at converting energy than single-rotor wind turbines.

Economic optimization of hybrid renewable energy systems supplying electrical and thermal loads of a tourist building in different climates

Due to the high potential of tourism in Iran and the high utilization of tourist buildings in Iran, as well as the high energy consumption in the buildings sector, this study aims to provide a feasible model for designing a renewable energy supply system for a tourist building in different climates of Iran. According to the country’s climate, 5 cities of Ahvaz, Bandar Abbas, Rasht, Mashhad, and Yazd were selected as the cities under study. The hybrid system also consists of photovoltaic panels, wind turbine, battery, and converter for power supply and boilers with natural gas fuel and geothermal heat pump to provide building thermal load. The heat pump is used to supply the load needed to preheat the building’s hot water. The system is connected to the electricity grid, so by selling excess electricity, the net project costs (NPC) will be reduced and the system can provide part of its need from the grid. The scenarios which were studied are of two categories. In the first category, all the thermal load is supplied by the boiler. After selecting the best economic scenario by Homer software in this category, the heat pump is added to the system by calculating the thermal load required to preheat the hot water. The scenarios used two types of wind turbines with a capacity of 10 and 50 kW and two types of 25-W panels with different efficiencies of 15.3% and 18%. Finally, a top-down scenario was chosen for each city. The best city to run the project on economic criteria is Mashhad with an NPC of $ 195,745 and a renewable fraction of $ 50.5. Using a heat pump to preheat the hot water, would also save 7% on fuel consumption and reduce CO2 production by 639,000 kg per year.

Exploring Dynamic P-Q Capability and Abnormal Operations Associated with PMSG Wind Turbines

With the proliferation of large-scale grid-connected wind farms, subsynchronous oscillation (SSO) incidents associated with Type-4 wind turbines (WTs) with a permanent magnet synchronous generator (PMSG) have occurred frequently. These incidents have caused severe reliability risks to the power grid. Conventionally, P-Q capability charts are utilized to ensure the safety operating region of a synchronous generator. However, a PMSG WT exhibits completely different and dynamic P-Q capability characteristics due to the difference in energy conversion technique and several critical factors related to the WT power converters. This paper presents a comprehensive dynamic P-Q capability study of a PMSG WT with sufficient and accurate considerations of the WT control and operation in the dq reference frame, its power converter constraints, and grid dynamics. Models of a PMSG WT are first developed based on its control principle in the dq reference frame. Then, algorithms for obtaining the P-Q capability charts of the WT are developed with the considerations of complete WT constraints in different aspects. The study analyzes the root cause of many abnormal operations of grid-connected PMSG WTs, reported in the literature, from the dynamic P-Q capability perspectives. The proposed study is verified via an electromagnetic transient (EMT) model of a grid-connected Type-4 WT.

Offshore wind farm layouts designer software's

Offshore wind energy can be considered one of the renewable energy sources with high force potential installed in marine areas. Consequently, the best wind farm layouts identified for constructing combined offshore renewable energy farms are crucial. To this aim, offshore wind potential analysis is essential to highlight the best offshore wind layouts for farm installation and development. Furthermore, the offshore wind farm layouts must be designed and developed based on the offshore wind accurate assessment to identify previously untapped marine regions. In this case, the wind speed distribution and correlation, wind direction, gust speed and gust direction for three sites have been analyzed, and then two offshore wind farm layout scenarios have been designed and analyzed based on two offshore wind turbine types in the Northwest Persian Gulf. In this case, offshore wind farm layouts software and tools have been reviewed as ubiquitous software tools. The results show Beacon M28 and Sea Island buoys location that the highest correlation between wind and gust speeds is between 87% and 98% in Beacon M28 and Sea Island Buoy, respectively. Considerably, the correlation between wind direction and wind speed is negligible. The Maximum likelihood algorithm, the WAsP algorithm, and the Least Squares algorithm have been used to analyze the wind energy potential in offshore buoy locations of the Northwest Persian Gulf. In addition, the wind energy generation potential has been evaluated in different case studies. For example, the Umm Al-Maradim buoy area has excellent potential for offshore wind energy generation based on the Maximum likelihood algorithm, WAsP algorithm, and Least Squares algorithm.

Investigation of Performance Enhancements of Savonius Wind Turbines through Additional Designs

This study examines the literature on improving the low performance of Savonius wind turbines, which are a type of vertical axis wind turbine. The literature studies on improving the performance of Savonius turbines have been summarized into two categories: interior structural design and exterior additional design. Due to the extensive nature of studies focusing on interior design changes, this research primarily focuses on performance studies related to exterior design modifications of Savonius wind turbines, particularly in recent years. This study aimed to provide a comprehensive examination of these performance studies and contribute to the existing literature by presenting a systematic reference on this issue. To achieve this objective, a thorough review of turbine exterior design studies has been conducted. The focus was on determining the percentage increase in power coefficient achieved by turbines with exterior design modifications compared to the classical turbine versions. Here, it has been determined that the power coefficient values of Savonius wind turbines can reach approximately 0.400 through interior design changes. However, with the implementation of additional exterior design modifications, these power coefficient values can be further increased to around 0.520. Thus, within the scope of this study, it has been determined that the turbine power coefficients show a fairly good increase with exterior design techniques compared to interior design techniques.

Techno-economic assessment of offshore wind energy potential at selected sites in the Gulf of Guinea

Offshore wind power has been found to stand out among the most dynamic renewable energy technologies. With its long coastal line, Nigeria has an overwhelming advantage in developing marine energy resources to relieve the power crisis effectively. This work analyzed and characterized observation data of sea-surface wind speed and direction at 30-minute intervals between 1979 and 2015 at five synoptic offshore stations in the Gulf of Guinea. The seasonal variations in hourly surface wind speed and directions as well as the Weibull distribution of wind speed and wind power at 100 m hub height were examined. The wind shears, capacity factors, and accumulated energy outputs for seven offshore wind turbine types were determined for the selected locations. In addition, the economic analysis of the selected offshore turbines using levelized cost of energy was carried out, while sensitivity analysis of the total levelized cost of energy to key input parameters was further determined. The results revealed large spatial and temporal variations in wind speed and wind power in the Gulf of Guinea. The most viable offshore site for wind energy exploitation was Agbami (the deepest offshore site), while Bonny (the shallow coastal site) had the least. The findings established very good fits (having mean bias (between −0.08 ms−1 and −2.44 ms−1), percentage bias (between −0.47% and −13.98%), correlation coefficients (between 0.97 and 0.98), Chi-square (between 0.2 and 1.2), and root mean square error (between 1.2 ms−1 and 3.1 ms−1)) between Weibull distribution and the actual wind data. The wind turbines with the highest and the lowest wind power densities, capacity factors, and power outputs across the seasons and sites were V236-15.0 MW and Siemens SWT113, respectively. The levelized cost of energy was considered for the deep waters due to the moderately high-capacity factors. The highest values ranged between 101.48 and 137.12 USD/MWh at Sea Eagle with V236-15 MW and V117-4.2 MW, respectively, while the lowest ranged from 52.29 to 69.66 USD/MWh at Agbami with V236-15 MW and Siemens (SWT113), respectively. The exploitation of Nigeria’s offshore wind resources could also be dedicated to producing renewable hydrogen and can serve to meet the country’s ambitious targets set for carbon neutrality by 2060.

Approaches Used In Adapting Metaheuristic Optimization Algorithms Developed For Continuous Problems to Discrete Problems

Many real-world problems such as determining the type and number of wind turbines, facility placement problems, job scheduling problems, are in the category of combinatorial optimization problems in terms of the type of decision variables. However, since many of the evolutionary optimization algorithms are developed for solving continuous optimization problems, they cannot be directly applied to optimization problems with discrete decision variables. Therefore, the continuous decision variable values generated by these metaheuristics need to be converted to binary values using some techniques. In other words, to apply such algorithms to discrete optimization problems, it is necessary to adapt the candidate solution vectors of the algorithms to discrete values and make changes in their working structures. In this study, firstly, adaptation methods that are frequently used in previous studies in transforming metaheuristic optimization algorithms designed for the solution of continuous optimization problems into discrete optimization algorithms are explained. Then, the popular location update strategies used in solving discrete optimization problems are explained. The presented work summarizes the process of adapting continuous optimization algorithms to solve combinatorial problems step by step.

Wind farm repowering optimization: a techno‐economic‐aesthetic approach

AbstractWhen a wind farm (WF) approaches the end of its life cycle, repowering is another opportunity for wind energy to prove its value. This paper proposes an optimization framework to guide the WF repowering, considering the power generation, the economic cost, and the aesthetic of the WF when various types of new wind turbines (WTs) are added. When calculating the wake deficits inside the WF, a three‐dimensional (3‐D) Gaussian wake model is applied which considers the height differences among the new WTs. A harmony pattern metric is used to assess the visual impact of the rebuilt WF. This optimization problem is formulated as an integer programming (IP) problem and is tackled by the integer particle swarm optimization (IPSO) algorithm. The wind data used for this optimization procedure is predicted by the auto‐regressive (AR) model. The case study on the OWEZ WF verifies the effectiveness of the proposed method. It is also validated that the application of predicted wind data is better than the historical data for WF repowering optimization.

A RANS-based surrogate model for simulating wind turbine interaction

A new wake surrogate model based on Reynolds-averaged Navier-Stokes (RANS) single rotor simulations is presented. The model relies on a series of three-dimensional pre-calculated deficit and added turbulence intensity flow fields, stored in a look-up table (LUT) as a function of the thrust coefficient and the ambient turbulence intensity. For any combination of these parameters, the flow around a wind turbine can be predicted by linearly interpolating within the look-up table. Furthermore, the resulting three-dimensional flow fields from different turbine sources can be superposed linearly to calculate the total wind farm flow. The model is implemented in PyWake and benchmarked against other, commonly employed engineering wake models, namely the Gaussian-Bastankhah, the N. O. Jensen and the Zong models, where RANS wind farm simulations are used as reference. In both full and partial wake cases, the surrogate model achieves a higher accuracy than any other model. Besides providing an accuracy comparable to a full RANS solution, the model can compute a flow case in the order of 1 s on a single processor. The main disadvantage is that the generation of the look-up table is time consuming, computationally expensive and can be memory demanding (especially if more inputs, such as the yaw misalignment angle, stability, etc. are added). Nevertheless, generating the LUT only has to be done once per wind turbine type.

Calculating energy capacity and capacity factors of wind energy generating in the Special Region of Yogyakarta using RETScreen Expert with variations in height

This study aims to get simulation results for the energy capacity and capacity factor of wind turbine type Wind Energy Solutions 80 kW in the Special Region of Yogyakarta at heights of 30m, 60m, and 90m. Energy capacity and capacity factors were calculated using the RETScreen Expert software simulation, beginning with gathering monthly wind speed data from the Special Region of Yogyakarta for use in simulations with height and wind turbine variations. This study indicates that wind turbine type Wind Energy Solutions 80 kW is best suited for installation in the Special Region of Yogyakarta with annual energy capacities of 42.6 MWh, 54.1 MWh, and 63.1 MWh, for heights of 30m, 60m, and 90m, respectively. Meanwhile, the capacity factors for 30m, 60m, and 90m are 6.1%, 7.7%, and 9.0%, respectively. Based on these results, it can be concluded that the wind turbine type Wind Energy Solutions 80 kW is a viable future alternative for the planned construction of a power plant in the Special Region of Yogyakarta. With the wind speed and a power capacity that is not excessively high, it is suitable as a wind turbine type for the Special Region of Yogyakarta.

Cause analysis of doubly-fed wind turbine faults

Doubly-fed wind turbine is the mainstream model at present. This paper first introduces the working principle of a doubly-fed wind power generation system, counts the fault frequency and fault duration of a doubly-fed wind turbine, and makes an in-depth analysis of the fault data in the recent two years. Then it summarizes the fault components and fault types of doubly-fed wind turbines, and on this basis, analyzes the causes of the faults, which can be used as a reference for wind farms to formulate fault prevention schemes for doubly-fed wind turbines.

Aerodynamic analysis of a 2-stage elliptical-bladed Savonius wind rotor: Numerical simulation and experimental validation

ABSTRACT The Savonius rotor is a type of vertical-axis wind turbine that utilizes drag to generate power. Its design simplicity and ability to self-start at low wind speeds make it an attractive option for small-scale wind energy generation. Previous research has focused on optimizing the geometric configuration of a 1-stage, 2-bladed rotor with semicircular blade profiles to improve its performance and mitigate negative torque. However, limited research has been conducted on 2-stage, 2-bladed Savonius rotors with elliptical blade profiles. The present investigation aims to fill this research gap by evaluating the aerodynamic characteristics of a 2-stage, 2-bladed Savonius rotor with elliptical profiles. 3D unsteady simulations using the SST k-ω turbulence model in ANSYS Fluent are conducted to evaluate the performance coefficients over a range of tip speed ratios. The numerical results are validated through wind tunnel experiments. The results show that the CPmax (maximum power coefficient) for the 1-stage rotor is 0.19 and 0.12 for numerical and experimental analyses, respectively. For the 2-stage rotor, the CPmax is 0.21 and 0.17 for numerical and experimental analyses, respectively. These findings suggest that the 2-stage rotor with elliptical profiles has the potential to efficiently harness wind energy.

A CNN encoder decoder LSTM model for sustainable wind power predictive analytics

Wind Power (WP) proliferates as one of the significant sustainable energies available in the form of temporal intervals. WP exists as a natural energy generating resource that depends on climatic parameters like wind speed, wind direction. These parameters are highly undetermined, thus collected over a fixed time interval. Hence, the nature of WP is quite uncertain over the time sequences and intricate to forecast. Accurate WP prediction has high significance for wind plants. It sequences the planning for different types of wind farm layouts, number and type of wind turbines required, peak load estimation, distribution areas and plans, cost and benefit risk mitigation etc. Long Short-Term Memory (LSTM) involves prediction using temporal relationships of data points collected over a period of time. The type of predictive analytics required in WP forecasting is very similar to the working of LSTM model. A hybrid Deep Learning (DL) based model using encoder decoder framework with Convolution Neural network (CNN) encoder with LSTM as decoder, named CNN Encoder-Decoder LSTM (CNN-ED-LSTM) is proposed in this study. Hence, to enhance the existing WP predictive analytics (WPPA), this paper focuses on optimization of WPPA using LSTM as the decoder and one-dimensional CNN as encoder. Evaluation of the proposed model is done using five different performance evaluation metrics Mean Absolute Error (MAE), Mean Squared Error (MSE), Mean Absolute Percentage Error (MAPE), Root Mean Squared Error (RMSE) and computational time. Also, other traditional DL models such as VanillaLSTM, StackedLSTM, CNN-LSTM and Bidirectional-LSTM (Bi-LSTM) are assessed over the same metrics. Additionally, five statistical models namely, ARIMA-LSTM, AutoARIMA, AutoRegressive Integrated Mean Average (ARIMA), AutoRegressive Mean Average (ARMA) and AutoRegressive (AR), are evaluated. Then, the efficacy of CNN-ED-LSTM is compared with these conventional models of time series predictive analytics as well as traditional DL models that are already used in different studies for WPPA. The proposed CNN-ED-LSTM model for WPPA is performing better than traditional DL models from 3.2% to 9.6% in terms of MSE metric and 3.2–7.5% for RMSE metric.

Fatigue Life Convergence of Offshore Wind Turbine Support Structure According to Wind Measurement Period

This paper investigated the fatigue life of offshore wind turbine (OWT) support structures. For this purpose, a 3 MW-capacity typical wind turbine is investigated using time-domain finite element simulations. In numerical simulations, different stochastic wind models corresponding to different accumulation periods are applied. Then, the stress-based fatigue life is estimated following the rain-flow counting algorithm and Palmgren-Miner linearly cumulative damage rule. The study also addresses the joint distribution of loads at the site of interest. Generally, the study emphasizes the significance of the long-term distribution of the applied environment loads and its influence on the fatigue life of OWT’s substructures. The results imply that the wind measurement period is directly linked to the fatigue life of offshore wind turbine support structures. Accordingly, its fatigue life is significantly reduced at the 25-year accumulative period of wind. Therefore, this study recommends that a sufficient number of accumulative periods of wind and other environmental loads should be considered appropriately.