Probabilistic model of combined wind and ice loads on overhead power line conductors

There is evidence that extreme ice loads combined with moderately high winds may cause catastrophic damage to overhead power lines and prolonged periods of electrical power outage. In this paper, a probabilistic model for combined wind and ice loads was developed for establishing realistic and conservative criteria for design and normalization. The proposed model combines icing of extreme thickness with a moderate wind speed, Vice, reduced by a reduction factor, kr, with respect to the extreme wind speed, Vmax. The evaluation of kr, which is the main purpose of this paper, is done by means of statistical analysis of samples taken from the same initial distribution of hourly wind speeds, Vh. The size of samples corresponds to the average annual icing persistency period, Tipp, observed in the climatic conditions of Quebec. This period, which was established in an earlier study by the authors using statistical analysis of data from the Hydro-Québec passive ice meter (PIM) network, is evaluated to be on average 144 h/year. It was found that kr ranges from 0.4 to 0.7, mainly as a function of the coefficient of variation (COV) of the initial distribution of wind speeds and the return period prescribed for extreme climatic loads.Key words: combined wind and ice loads, probabilistic model, overhead transmission lines.

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Active Conical and Planetary Gearing System for Wind Turbines

Volume 6: Energy, Parts A and B ◽

10.1115/imece2012-86430 ◽

2012 ◽

Author(s):

M. Salim Azzouz ◽

Anjolajesu Fagbe ◽

Zachary Evetts ◽

Ethan Rosales

Keyword(s):

Wind Speed ◽

Wind Turbine ◽

Design Theory ◽

Planetary System ◽

Experimental Testing ◽

Electrical Power ◽

Angular Speed ◽

Equilibrium Equations ◽

Input Shaft ◽

Wind Speeds

The purpose of this research project is to explore the possibility of harvesting the energy of the wind by taking advantage of higher wind speeds. Two active gearbox systems allowing a variable speed at the input shaft and delivering a constant speed at the output shaft are currently being built and tested. The first system consists of an assembly of spur, planetary, and ring gears run and controlled by electrical motors. The second system consists of an assembly of a conical shaft, a wheel, and a set of centrifugal masses. The two gearing systems can act separately as a continuously variable transmission (CVT) between the wind turbine hub and the electricity generator which requires an entry speed corresponding to a frequency of 60 Hz. The two gearing systems are designed using the SolidWorks CAD software for modeling and simulation, and the gearing design theory is used to dimension the required spur, planetary and ring gears for the first proposed system. Betz’s law associated with appropriate and realistic wind turbine efficiency is used to estimate the wind power transferred to the turbine hub. The law is also used to determine the hub angular speed as a function of the wind speed. The kinematic gearing theory is used to establish the different gearing ratios of the planetary system, and the kinematic relationships between the system stages. The forces and torques acting on the first and the second systems are computed using the equilibrium equations. The speed ratios are calculated for the first and second system using the kinematic theory. Ideally, the electrical power consumed by the regulating motor for the first system is minimal so that a maximum percentage of the generated electrical power is supplied to the electricity grid. For the second system the totality of the harvested power is transmitted through the conical/wheel system. For the planetary system, when the wind speed deviates from a certain optimum value, the electrical controls activate a regulating motor to guarantee that the generator input speed remains constant. Currently, a prototype of a more robust planetary gearing system than a previously made one is under construction while a newly constructed conical system is under experimental testing. Running speeds, torques, power transfer and distribution for the two systems will be measured. The generated electrical power is measured using different load resistances and compared to the electrical power consumed by the regulating motor for the planetary system. The torques are measured using a prony brake system while the angular speeds are measured using tachometers. It is expected that the power consumed by the regulating motor for the gearing system will remain a small percentage of the power supplied to the grid for various hub input speeds.

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Performance Evaluation of a Novel Small Wind Turbine: UAE Case Study

ASME 2016 Power Conference ◽

10.1115/power2016-59242 ◽

2016 ◽

Cited By ~ 1

Author(s):

Sayem Zafar ◽

Mohamed Gadalla ◽

Mohammad Ismail Al-Naiser

Keyword(s):

Wind Speed ◽

Wind Turbine ◽

United Arab Emirates ◽

Electrical Power ◽

Electrical Efficiency ◽

Wind Speeds ◽

Small Wind Turbine ◽

Sufficient Power ◽

Personal Use ◽

Domestic Power

A small personal use wind turbine (PWT) is studied and tested for power evaluation under different wind speed conditions. The wind turbine has small blades with FX 63137 airfoil. The blades are non-tapered and non-twisted to be economical and easy to manufacture. The blade span is 1.52 m which makes it small enough for personal domestic use yet big enough to produce sufficient power. The PWT size satisfies the requirements for rooftop small wind turbine for domestic power generation. The study is conducted in United Arab Emirates (UAE) and the PWT is installed in an open area to test under the natural conditions. Readings are recorded for wind speeds, generator RPMs, current and voltage for different timings and conditions. The PWT is tested at a variety of wind speeds to establish the operating range of the wind turbine. Using the calculated electrical power and wind power values, corresponding electrical efficiency is determined. Results are evaluated for electrical power and electrical efficiency against wind speed. The result suggests better performance and efficiency for continuous wind speed conditions. It also shows the PWT can effectively generate power under the conditions found in UAE.

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Evaluation of the Effect of Blades Number on the Performance of Pico Wind Turbines

Iraqi Journal of Industrial Research ◽

10.53523/ijoirvol8i1id20 ◽

2021 ◽

Vol 8 (1) ◽

pp. 29-39

Author(s):

Yasir Abood ◽

Tariq A. Ismail ◽

Omar A. Abdulrazzaq ◽

Haider S. Hussein

Keyword(s):

Wind Speed ◽

Wind Turbine ◽

Wind Turbines ◽

Electrical Power ◽

Internal Resistance ◽

Power Coefficient ◽

Sharp Reduction ◽

Wind Speeds ◽

Air Blower

In this paper, the influence of blades number on the performance of pico wind turbine was investigated by using a small-motorized axial DC fan with a rated power of 4W. Fixed streaming air blower was used as a source of wind. Varying in wind speed was accomplished by changing the distance from the blower. A resistor equals to the turbine internal resistance was utilized as a load to collect the electrical power across the load at various wind speeds and for fans of different blades (1, 2, and 5). Values of the cut-in and cut-out speeds were extracted from the power plot. Rated power was recorded, as well. The results have shown that the rated power generated by turbine has decreased due to the reduction of blades number (i.e., reduction in solidity) from 2.6W for a 5-bladed turbine to 0.665W for a 2-bladed turbine and to 0.13W for a 1-bladed turbine. Moreover, the cut-in speed (initial electrical generating speed) has increased from 4.9m/s for 5-bladed to 8m/s for 2-bladed, then to 19.15m/s for 1-bladed. These results are explained by the balancing problems during rotation (polar asymmetrical rotor), and it is seen that the reduction of blades has made a sharp reduction in power coefficient.

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PENGARUH JUMLAH SUDU TERHADAP KINERJA TURBIN ANGIN SUMBU VERTIKAL TIPE DARRIEUS-H NACA 3412 DENGAN SUDUT PITCH 00

INFO-TEKNIK ◽

10.20527/jit.v19i2.153 ◽

2018 ◽

Vol 19 (2) ◽

pp. 195

Author(s):

Arif Rochman Fachrudin

Keyword(s):

Renewable Energy ◽

Wind Speed ◽

Electric Power ◽

Wind Turbines ◽

Mechanical Energy ◽

Renewable Energy Sources ◽

Electrical Power ◽

Wind Speeds ◽

Turbine Performance ◽

The Given

Potential and utilization of renewable energy in Indonesia is still very small. Oneof the renewable energy sources is wind energy. The use of wind turbines, windenergy is converted into mechanical energy and can then generate electricitythrough a generator. Wind turbines are environmentally friendly, inexpensive,easy to operate and easy to maintain. The purpose of this study was to determinethe effect on the performance of the number of blades and wind speed for thevertical axis wind turbine type darrieus H with the NACA profile 3412 with apitch 0o angle. This study uses an experimental method, with a number of bladesand varying wind speeds. The number of blades given is 2 units, 3 units and 4units. The speed of the given wind is 3.3 m / s, 3.5 m / s, 3.7 m / s, and 3.9 m / s.Performance is obtained from the electrical power produced by a generatormounted on the turbine axis. The results showed that the turbine performance wasinfluenced by the number of blades. The highest power in the number of bladeswas 4 units at a wind speed of 3.3 m / s which resulted in electric power of 5.166Watt. The lowest electric power is produced on turbines with a number of units of2 units at a wind speed of 3.3 m / s, which is 3.0173 Watts. The blade is 2 unitsand 3 units, at a wind speed of 3.3 m / s; 3.5 m / s; 3.7 m / s and 3.9 m / s, theelectrical power produced is relatively the same, while in blades 4 units, thedifference in wind speed (3.3 m / s; 3.5 m / s; 3.7 m / s and 3.9 m / s) produce adifference in the electrical power produced

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Assessment of regional weather and climatic conditions as health risk factors according to the wind-cold index

Sanitarnyj vrač (Sanitary Inspector) ◽

10.33920/med-08-2103-04 ◽

2021 ◽

pp. 35-43

Author(s):

Rofail Salykhovich Rakhmanov ◽

Elena Sergeevna Bogomolova ◽

Denis Alekseevich Narutdinov ◽

Yuriy Gennadievich Piskarev ◽

Lyudmila Ignatievna Tokareva

Keyword(s):

Wind Speed ◽

Health Risk ◽

Well Being ◽

Climatic Conditions ◽

Severe Weather ◽

The Body ◽

Wind Speeds ◽

Average Temperature ◽

Regional Features ◽

Climatic Characteristics

Determined the cold periods of the year in different weather and climatic conditions of the Krasnoyarsk Territory. We assessed the health risk of the population under the influence of temperature and wind speed in an open area according to the wind-cold index (which determines the comfort and discomfort of the weather). The average monthly daily, average monthly minimum temperatures and wind speeds were estimated for 10 years (2010–2019). Wind speed was assessed using the Bothford scale. In terms of ambient temperature, the cold period lasted: subarctic zone (Norilsk) — 5, moderate continental (Krasnoyarsk and Minusinsk) — 3 months. According to the wind-cold index (in terms of average temperature and wind speed), the period of severe weather in the subarctic zone lasted from 6 to 7 months a year. Three months of the year, the meteorological perception was assessed as «very» and 1 month — as «extremely cold». In the region of Krasnoyarsk, as well as in Minusinsk, the cold «uncomfortable period» was lengthened by 1 month. The health risk under the combined influence of the minimum temperature and maximum wind increased in the subarctic zone up to 8, moderate continental up to 5 (Krasnoyarsk) — 5–6 (Minusinsk) months. In the area of Norilsk, the period, assessed as «extremely cold, exposed parts of the body can be supercooled by 10 minutes,» extended by 4 months, in Krasnoyarsk such a period was possible in January, Minusinsk was recorded in January and February. In the conditions of one climatic zone (Krasnoyarsk, Minusinsk), regional features of weather and climatic characteristics (duration of cold and warm periods, temperature, wind speed, severity and duration of periods of severe weather), which can affect the well-being and state of health of the population, have been identified.

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Again about reliability characteristics of electrical power grids elements

E3S Web of Conferences ◽

10.1051/e3sconf/20185801002 ◽

2018 ◽

Vol 58 ◽

pp. 01002

Author(s):

Abdula Abdurakhmanov ◽

Sergey Glushkin ◽

Vladislav Plotnikov ◽

Andrey Shuntov

Keyword(s):

Statistical Analysis ◽

Transmission Line ◽

Transmission Lines ◽

Electrical Power ◽

Power Grids ◽

Overhead Transmission Line ◽

Overhead Transmission Lines ◽

Network Layout ◽

Reliability Characteristics ◽

Technical Solutions

The reliability characteristics of the (auto)transformers and overhead transmission lines of the unified national electric grid are subjected to statistical analysis. It is shown that their scheduled outages for scheduled or unscheduled repairs, as well as maintenance, weaken the network layout much more than emergency repairs. At the same time, there was a noticeable deterioration in the (auto)transformers and overhead transmission line reliability indexes over the last 30 years, which requires the development and adoption of appropriate organizational and technical solutions.

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OPTIMALISASI PEMANFAATAN DATA ARAH DAN KECEPATAN ANGIN POLA MONSUNAL UNTUK KAJIAN PEMETAAN POTENSI ENERGI ANGIN DI WILAYAH NUSA TENGGARA BARAT

Prosiding SNFA (Seminar Nasional Fisika dan Aplikasinya) ◽

10.20961/prosidingsnfa.v3i0.28502 ◽

2019 ◽

Vol 3 ◽

pp. 14

Author(s):

Abdul Hamid Al Habib ◽

Kholis Nur Cahyo ◽

Prasetyo Umar Firdiyanto ◽

Paulus Agus Winarso

Keyword(s):

Wind Speed ◽

Wind Energy ◽

Wind Turbines ◽

Electrical Power ◽

The West ◽

Wind Speeds ◽

Wind Potential ◽

High Winds ◽

Turbine Installation ◽

Potential Area

Abstract: The National Institute of Aeronautics and Space (LAPAN) as of July 18 2017 released data that from 166 locations studied, there were 35 locations that had good wind potential with wind speeds above 5 meters per second at a height of 50 meters. Regions that have good wind speeds, one of which is West Nusa Tenggara (NTB). West Nusa Tenggara is an area that is crossed by monsunal wind patterns and is an island surrounded by beaches so that the West Nusa Tenggara region receives high winds. This can potentially be installed by wind turbines to be able to convert wind energy into electricity. Wind direction and speed data obtained from satellites are processed into average data then adjusted to the wind speed threshold that can rotate wind turbines. The results obtained are mapped using the GrADS application to determine the potential area for horizontal axis type wind turbine installation at a height of 10 meters based on monsunal pattern direction and wind speed. This study will provide recommendations on potential areas of wind energy and predictions of electrical power that will be generated from the use of these maps. The results of the study show that the West Nusa Tenggara region by utilizing wind energy can create electricity in a year totaling 14067.4026 kWh.Abstrak: Lembaga Penerbangan dan Antariksa Nasional (LAPAN) per 18 Juli 2017 merilis data bahwa dari 166 lokasi yang diteliti, terdapat 35 lokasi yang mempunyai potensi angin yang bagus dengan kecepatan angin diatas 5 meter perdetik pada ketinggian 50 meter. Daerah yang mempunyai kecepatan angin bagus tersebut, salah satunya adalah wilayah Nusa Tenggara Barat (NTB). Nusa Tenggara Barat merupakan wilayah yang dilintasi oleh pola angin monsunal dan merupakan pulau yang dikelilingi oleh pantai sehingga wilayah Nusa Tenggara Barat menerima hembusan angin yang cukup tinggi. Hal ini dapat berpotensi untuk dipasang turbin angin untuk dapat mengkonversi energi angin menjadi energi listrik. Data arah dan kecepatan angin yang diperoleh dari satelit diolah menjadi data rata-rata kemudian disesuaikan ke dalam batas ambang kecepatan angin yang dapat memutar turbin angin. Hasil yang diperoleh tersebut dipetakan dengan menggunakan aplikasi GrADS guna menetukan wilayah yang berpotensi untuk pemasangan turbin angin jenis sumbu horizontal pada ketinggian 10 meter berdasarkan arah dan kecepatan angin pola monsunal. Penelitian ini akan memberikan rekomendasi wilayah potensi energi angin serta prediksi daya listrik yang akan dihasilkan dari pemanfaatan peta tersebut. Hasil penelitian menunjukan wilayah Nusa Tenggara Barat dengan memanfaatkan energi angin dapat menciptakan energi listrik dalam setahun berjumlah 14067.4026 kWh.

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A study on flow as affected by the shape and wind speed of ventilated seat

International Journal of Engineering & Technology ◽

10.14419/ijet.v7i2.33.14175 ◽

2018 ◽

Vol 7 (3.3) ◽

pp. 311

Author(s):

Kye Kwang Choi ◽

Jae Ung Cho

Keyword(s):

Statistical Analysis ◽

Wind Speed ◽

Flow Path ◽

Maximum Speed ◽

Maximum Pressure ◽

Wind Speeds ◽

Ansys Cfx ◽

Design Factors

Background/Objectives: We studied the ventilated seats with amenities. The study has its purpose in checking the flow as affected by the shape of the ventilated seats and thereby acquiring the design factors.Methods/Statistical analysis: In order to acquire the design factors for ventilated seats as affected by the shapes and wind speeds of the different models, we used CATIA program to design the shape, of which the flow was analyzed with ANSYS CFX program. Thus, we have acquired the design factors for ventilated seats, which data can be used to ensure higher levels of efficiency as compared to the shapes before.Findings: For analyzing, we placed an inlet at the vent at the bottom and placed an outlet at the top by setting a boundary around it. From the setup, which had the initial wind speed at 15m/s, the wind speed within the boundary was 29.91m/s for model 1 and 44.81m/s for model 2. At the initial wind speed of 30m/s, we got a wind speed of 60.25m/s for model 1 and 88.60m/s for model 2. As for the pressure and speed in the flow path as the initial wind speed of 15m/s, we got the maximum pressure of 100.60kPa and the maximum speed of 29.45m/s. For model 2, we got the maximum pressure of 102.30kPa and the maximum speed of 44.81m/s. At the initial wind speed of 30m/s, we got the maximum pressure of 102.30kPa and the maximum speed of 60.25m/s for model 1. For model 2, we got the maximum pressure of 105.10kPa and the maximum speed of 88.60m/s.Improvements/Applications: Through the data obtained from this analysis, the varied seat structure for additional amenities can be improved and applied with more design factors.

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RANCANG BANGUN TURBIN ANGIN SAVONIUS 200 WATT

Conference SENATIK STT Adisutjipto Yogyakarta ◽

10.28989/senatik.v2i0.35 ◽

2016 ◽

Vol 2 ◽

pp. 71

Author(s):

Daniel Rudianto

Keyword(s):

Wind Speed ◽

Turbine Blade ◽

Electrical Power ◽

Electrical Energy ◽

Test Results ◽

Small Power ◽

Wind Speeds ◽

Turbine Shaft ◽

District Government ◽

The Cost

This study aimed to establish the type of Savonius wind turbines that capable of generating electric power of 200 Watts. This objective relates to Bantul District Government program which plans to build wind turbin generating electrical power (Pembangkit Listrik Tenaga Bayu, PLTB) 200 Watt as a backup power source for powering cooling fish caught by fishermen in the southern coast. Savonius Turbine chosen with consideration that it has simple construction so that the cost is not expensive, not depending on the direction of the wind, and is suitable for small power plants.Design of Savonius turbine blade has been completed, the turbine blade height 168 cm and a diameter of 55 cm. Blade turbine mounted on an arm along 55 cm from the turbine shaft and separate 120º. The turbine is supported by a 3-foot-tall turbines framework 2,5 m iron box 4 cm x 4 cm. The test simulated to determine the turbine rotation has been performed at varying wind speeds, i.e. 2 m /s, 4 m /s and 6 m /s.Based on test results, the turbine is capable of rotating an average of 54,2 rpm at a wind speed of 2 m /s; 86,8 rpm at a wind speed of 4 m /s; and 124,2 rpm at a wind speed of 6 m /s. These test results indicate that the Savonius turbines can be used to drive a generator producing the need of electrical energy

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Simulation of Wind Speeds with Spatio-Temporal Correlation

Applied Sciences ◽

10.3390/app11083355 ◽

2021 ◽

Vol 11 (8) ◽

pp. 3355

Author(s):

Moisés Cordeiro-Costas ◽

Daniel Villanueva ◽

Andrés E. Feijóo-Lorenzo ◽

Javier Martínez-Torres

Keyword(s):

Wind Speed ◽

Power Systems ◽

Electrical Power ◽

Primary Source ◽

Wind Farms ◽

Temporal Correlation ◽

Electrical Power Systems ◽

Wind Speeds ◽

Temporal Correlations ◽

Spatio Temporal

Nowadays, there is a growing trend to incorporate renewables in electrical power systems and, in particular, wind energy, which has become an important primary source in the electricity mix of many countries, where wind farms have been proliferating in recent years. This circumstance makes it particularly interesting to understand wind behavior because generated power depends on it. In this paper, a method is proposed to synthetically generate sequences of wind speed values satisfying two important constraints. The first consists of fitting the given statistical distributions, as the generally accepted fact is assumed that the measured wind speed in a location follows a certain distribution. The second consists of imposing spatial and temporal correlations among the simulated wind speed sequences. The method was successfully checked under different scenarios, depending on variables, such as the number of locations, the duration of the data collection period or the size of the simulated series, and the results were of high accuracy.

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