Types Of Wind Generators Research Articles

EFFICIENCY OF A WIND PLANT IN REAL CONDITIONS WITH ADDITIONAL COSTS AND THE MARKET PRICE OF ELECTRICITY

In its development, the global energy sector is constantly demonstrating the growth of electricity consumption. Traditional power plants in this process ensure an increase in greenhouse emissions and aggravation of climate problems, which are becoming more relevant every year. Against this background, modern alternative energy sources, namely wind power plants, contribute to reducing the impact of traditional power plants and encourage solving environmental problems. The development of global wind energy is accompanied by the growth of unit capacities of generators of wind power plants. The paper analyzes the efficiency of a wind power plant based on modern wind generators for predetermined location conditions, taking into account operating costs based on operational experience and based on the assessment of the power plant's participation in the balancing market of electricity with a waiver of the "green tariff". Calculations of the technical and economic indicators of an imaginary designed 4-unit wind power plant with various wind generators under the wind conditions of a predetermined industrial site located in the Carpathian region of Ukraine were carried out. The calculations take into account the modern typical characteristics of wind generators, additional operating costs and the estimated cost of electricity purchase of the station under the "green tariff" and in the conditions of a balancing electricity market to compare economic efficiency. In order to make an optimal design technical decision with a comparative assessment, three types of wind generators were determined for installation at an imaginary wind farm - Enercon E-175 EP5, Vestas V136-4.5 MW and Vestas V172-7.2 MW. In the conditions of the predetermined construction site of the projected wind farm on the Carpathian ridges of Ukraine, the measured and calculated annual probability distribution of wind speed according to the analytical Weibull distribution is applied, and the characteristics of the annual productivity of the 4-unit wind farm for the adopted three types of wind generators are given. The technical and economic characteristics were obtained in the work: capital investment, operating costs, characteristics of electricity production, the gross profit during the annual operation of the wind power plant with three options for installing wind generators was calculated, making it possible to estimate the payback time of the investment in the construction of the wind plant. So, for a 4-unit station with generators of the Enercon E-175 EP5, the payback period is 3.3 years, and with wind generators of the Vestas V136-4.5 MW - 3.4 years, as well as for the Vestas V172-7.2 MW in operating conditions of the "green tariff" and, respectively, 2.9 years, 2.9 years and 3.0 years under conditions of sale of electricity at balancing market prices. Additional operating costs for the disposal of worn wind turbine blades do not have a significant impact on the overall cost indicators and amount to 5-7% of the total costs.

Design of wind power plant with a turbine capacity of 300 Watt

Wind is a renewable energy source that is abundant and can be used for areas that have not been reached by electricity. Wind power plants can be used to meet household-scale electricity needs. The purpose of this study is to design, test, and analyze wind power plants as an alternative power source for home lighting. This research method uses a horizontal type wind turbine that has 3 blades, a three-phase AC permanent magnet generator type wind turbine that can generate electricity up to 300-310 Watts. The results of the wind turbine design have worked well. Testing the voltage and current from the controller to the battery produces the highest voltage of 14 Volts, with a current of 1.38 Ampere at a wind speed of 4.1 m/s. The higher the wind speed, the higher the voltage and current. The magnitude of the DC and AC voltages is determined by the wind speed and also when it is loaded.

Оцінка ефективності вітрогенераторів в реальних умовах з додатковими експлуатаційними витратами

The development of world energy is constantly accompanied by the growth of electricity consumption. Traditional sources of electricity in this process contribute to the growth of greenhouse emissions and the aggravation of climate problems, which are becoming more urgent every year. Against this background, alternative sources of electricity, in particular wind power plants, reduce the impact of traditional sources and contribute to solving environmental problems. The development of wind power generation is accompanied by an increase in the unit capacities of wind generators. The article analyzes the efficiency of the operation of a wind power plant with modern wind generators for certain location conditions, taking into account additional operating costs based on operating experience. Calculations of the technical and economic operational indicators of the designed four-unit wind power plant with various types of wind generators were carried out. During these calculations the wind conditions of a specific industrial territory for the construction of wind power plant were taken into account. This industrial territory is located in the Carpathian region of Ukraine. At the same time, the modern typical power capacities of wind generators and additional costs during the operation of wind power plants were taken into account. In order to make the optimal technical design decision for comparative evaluation, two types of wind generators — Enercon E-175 EP5 and Vestas V136-4.5 MW — were selected for installation at the wind power plant. For the determined location of the wind power plant at the upper reaches of the Carpathian mountain ranges in the Lviv region of Ukraine (coordinates of the area are (lat., lon.) 49.2470; 22.8763), the annual wind probability characteristic was calculated according to the Weibull analytical characteristic. According to these data, in the article the characteristics of an annual electrical productivity of the designed 4-unit wind power plant for the selected two types of wind generators were given. The obtained technical and economic indicators: the capital investment, operating costs, performance characteristics and calculated gross profits during the year of operation of the considered wind power plant with two types of wind generators — made it possible to estimate the payback period of its equipment. So, for a 4-unit station with wind generators of the Enercon E-175 EP5 type, the payback period is 3.7 years, and with wind generators of the Vestas V136-4.5 MW type — 3.6 years.

An internal parallel capacitor control strategy for DC-link voltage stabilization of PMSG-based wind turbine under various fault conditions

In recent years, wind energy conversion systems (WECSs) have been growing rapidly. Due to various advantages, a permanent magnet synchronous generator (PMSG) is an appealing solution among different types of wind generators. As wind power penetration level in the grid increases, wind power impacts the grid and vice versa. The most essential concerns in the system are voltage sag and swell, and grid code compliance, particularly for low voltage ride-through (LVRT) and high voltage ride-through (HVRT) capability, is a pressing necessity. This paper presents a parallel capacitor (PC) control strategy to enhance the LVRT and HVRT capability of PMSG. Furthermore, this study presents a method for the sizing of a PC system for the reduction of the overvoltage of the DC-link during voltage sags and swell. Fast Fourier transform analysis is used to determine the total harmonic distortion (THD) for the injected current into the grid. The obtained results illustrate the effectiveness of the proposed system in keeping the DC-link voltage below the limit, power quality improvement, and increasing the LVRT and HVRT capability. Models of wind turbine, PMSG, and PC control system are built using MATLAB/SIMULINK software.

Effect of Grid Faults on Dominant Wind Generators for Electric Power System Integration:A Comparison and Assessment

In recent times, various types of wind generators have been linked to the power grids globally and the focus has been to control them to be more efficient and reliable. This study concisely discusses performance analysis, modeling, and assessment of different wind generators (permanent magnet synchronous generator, doubly-fed induction generator, squirrel cage induction generator), covering their benefits, drawbacks, and impact on the electric power systems. This comparison aims to guarantee that their technical and economic evaluations are comparable, allowing engineers to make a more informed decision about which generator is best suitable for their installation. Findings for the investigated wind generators lead to significant observations about their application fields, such as permanent magnet synchronous generator outperforms doubly-fed induction generator and squirrel cage induction generator, especially during grid disruptions; on the other hand, squirrel cage induction generator is simple and inexpensive.

An enhancement approach of Reboost converter for unification of disparate WECS with the utility grid system

The WECS is an important phenomenon to reduce green house gas emission. The power generated from wind energy is clean, zero emission and volatility. The generation of Wind energy is stochastic due to the variation of velocity of wind. The Unification of WECS with the utility grid is a major formidable area of research. The integration of grid with WECS is done by means of Rotor side converter and Grid side inverter. These two converters are linked by using a DC link capacitor in a conventional system. In this paper, a novel topology had been proposed. The conventional system DC link element is replaced by Reboost converter. A Reboost converter is a DC–DC converter which bestows boosting or increased output voltage. It comprises a power MOSFET switch, hence the switching stress is minimized and efficiency of the proposed converter is predominant. The Reboost converter dispenses a continuous input current that lessen the voltage stress. The output ripple voltage and total harmonic distortion factor are minimized. A comparative analysis on different types of wind generators are performed by implementing the Reboost converter. The input voltage total harmonic distortion, output voltage, output power and output voltage total harmonic distortion factor are determined. The MATLAB Simulation on different types of wind generators are analyzed and the results prove that Doubly fed induction generators are expedient. • The Wind energy conversion system is a blooming technology in the field of research area to meet the energy demands in the world. • The article focuses on performance study of the proposed Reboost converter on the different wind energy conversion systems. • According to the literature survey and the simulation results attained, it had been concluded in the article the proposed converter with Doubly fed Induction Generator bestows the better performance on comparison with Permanent Magnet Synchronous Generator and Squirrel Cage Induction Generator. • The circuit description of the proposed converter along with its modal circuit had been elaborated in the article. • The Simulation Circuit Schematic of Reboost Converter with Utility Grid for PMSG, SCIG and DFIG based WECS are embraced with its performance study and its values are verified experimentally.

Multi-degree-of-freedom high-efficiency wind power generation system and its optimal regulation based on short-term wind forecasting

The efficient and stable operation of wind generators is important for the realization of large-scale power generation. In this study, a multi-degree-of-freedom (multi-DoF) wind power generation system (WPGS) based on short-term wind forecasting is proposed, which is suitable for off-grid types of operation. First, the change in wind direction and speed over 24 h was obtained through short-term wind forecasting considering the relationship between wind speed and direction based on the Gaussian mixture model (GMM). Meanwhile, a novel control strategy, long short-term memory network-based model predictive control, was proposed to guide the real-time wind aligning operation of a wind generator based on wind forecasting results. Finally, a multi-DoF permanent-magnet synchronous wind generator was deflected around the rotor shaft to align it toward the wind direction, thereby substituting the yaw system in the traditional wind generator. The proposed system was evaluated by comparing it with other existing models, and its performance was found to be superior to the existing models in all aspects. This is the first study to generate a complete set of high-efficiency WPGSs, which is composed of wind forecasting results, a control system, and a new type of wind generator. The proposed system improves the passive and hysteretic operation modes of traditional wind turbines and significantly increases the efficiency of wind generators and is expected to serve as a reference for future research in this area.

Wind-driven permanent magnet synchronous generators connected to a power grid: Existing perspective and future aspects

Scholars are motivated to work in the field of renewable energy systems (RESs) especially on grid-connected wind generators because of the exciting and noticeable developments going on in this area. This progress is utilized to obtain the maximal, efficient, and stable electric power from the RESs and integrating it into existing systems to improve its efficiency, stability, reliability, and overall power quality. Recently, permanent magnet synchronous generators (PMSGs) have become the main pillar of advanced wind systems thanks to their fascinating pluses over other types of wind generators. This paper presents the up-to-date trends in converter topologies, control approaches, maximal power production methods, and grid integration issues for PMSG-based wind systems. The performed statistical analyses assure the dominance of the two-level back-to-back converter among the studied power converter topologies, field-oriented control method for the machine side converter, voltage oriented control method for the grid side converter control, perturb and observe algorithm amongst the studied maximum power point techniques, and fault ride-through capability out of grid integration issues. Further, recent general trends in technological advancements for PMSG wind system components are illustrated as a pie chart in terms of percentage figures. It is expected that the researchers working in this field would benefit from this article in terms of the presented state-of-the-art statistical analyses and its related literature given in this study.

Performance of Low Voltage Ride-Through Protection Techniques for DFIG Wind Generator.(Dept.E)

Due to the increase of the number of wind turbines connected directly to the electric utility grid, new regulator codes have been issued that require Low-Voltage Ride-Through capability (LVRT) for wind turbines so that they can remain online and support the electric grid during low voltage fault events instead of direct tripping of the wind turbines. This LVRT capability will increase the stability of the network and reduce the need for load shedding after the fault clearance. Each utility has its own grid codes for this LVRT. There are many types of wind generators, and currently the Doubly Fed Induction Generator (DFIG) is the most popular type among the leading wind turbine (WT) manufacturers. In this paper five LVRT methods for protection of DFIG during LV events are implemented and compared. The five methods are Crowbar, DC Chopper, series dynamic resistances, and two hybrid methods that combine DC chopp er with Crowbar and DC chopper with series dynamic resistances respectively. These methods were tested under different types of fault including symmetrical and unsymmetrical faults and their performances were compared.

WLEACH: Real-Time Meteorological Data Based Wind LEACH

Introduction:Nowadays, Wireless Sensor Network (WSN) plays an important role in various fields. The limited power capability of the sensor nodes in the WSN brings constraints on the performance of the network. Low Energy Adaptive Clustering Hierarchy (LEACH) is a promising protocol for WSN that suffers from higher energy consumption.Objective:The primary objective of this study is to give an alternate harvesting resource power to sensor nodes in the LEACH algorithm which can be equally capable of providing the same or sometimes better results.Methods:This study is based on real-time meteorological data. A real-time wind speed data is taken for the starting of a day to the end of the day on an hourly basis from the weather forecast. Now to convert this rotational energy into electrical energy, we used two types of wind turbines. For the proposed methodology, a micro wind turbine generator and 300watt wind turbine are used. Then this converted electrical energy is given to sensor nodes. For the clustering, the wind power operated nodes are given maximum preference to be elected as the cluster heads based on realtime wind meteorological data. We consider 10 wind-powered sensor nodes. As we increase the number of wind-powered sensor nodes in the network, the performance is increased in terms of a lifetime but then increases the complexity of the network. These wind-powered nodes remain alive in the network. Since the deployment of the sensor nodes is random, each simulation runs for 5 times and the average of first node dead, half node dead and last node dead is considered.Results:The experimental results for the micro wind turbine generator are compared based on with and without the MPPT controller. MPPT controller gives the maximum power by using the tip speed ratio control, power signal feedback control, and hill climb search control method. Therefore, the network lifetime should be higher for the MPPT based wind generator. Network lifetime and Energy consumption are compared for a micro wind turbine generator and 300watt wind turbine. Finally, the performance of the proposed system is compared with the modified solar LEACH implemented using real-time meteorological data.Conclusion:This paper has investigated the wind-based LEACH which uses the real-time meteorological data for the selection of the cluster head. Two types of wind generators are considered for the implementation and it is found that the performance of the commercial 300W wind turbine and the micro wind turbine with and without MPPT is almost similar since the data from both wind turbines are given on hourly basis. The performance of the wLEACH is compared with the sLEACH which shows that the network lifespan of the wLEACH is also nearly the same compared to the sLEACH. However, it was found that wind power generation is cheaper and efficient than solar power generation. Therefore, it is inferred that this proposed wLEACH provides a costefficient solution.

IoT AND WIND POWER SUPPLY IN CONTEX OF THE NEW ONPU s SPECIALIZATION

The article describes the current state of wind energy, the main achievements in this area and its problems. One of the problems is the lack of qualified specialists in this field. To solve this problem, the training course "Renewable Energy Sources" was created at the Odessa Polytechnic University for the specialization "Engineering of smart electrical systems". For the course, a laboratory stand "Vetroenergetika" was developed. The stand simulates the operation of a wind generator and displays the main electrical and mechanical performance indicators. It is also provided for the output of these values to the computer using the microcontroller and the platform. With a computer, all the main dependencies are built in real time to monitor the state of the wind generator. Also, a laboratory workshop on the topic "Wind power" was prepared, which, at the moment, included four laboratory works, namely: the study of the external characteristics of the wind generator when the electrical load changes, the study of the dependence of the change in power on the wind speed, the study of the dependence of the change in power on the angle of attack wind flow for two different types of wind generators and a study of the dependence of the speed on the electrical load. The plan of the experiments and the results obtained during the laboratory tests of the stand are described in detail. Each of the above dependencies has practical applications in the production and operation of wind turbines. The authors do not consider the list of possible researches complete and it will be replenished as the stand and laboratory workshop develop. Also, the proposed teaching methodology can by no means be considered the only and complete one.

Power-Angle Modulation Controller to Support Transient Stability of Power Systems Dominated by Power Electronic Interfaced Wind Generation

During the last few years, electric power systems have undergone a widespread shift from conventional fossil-based generation toward renewable energy-based generation. Variable speed wind generators utilizing full-scale power electronics converters are becoming the preferred technology among other types of renewable-based generation, due to the high flexibility to implement different control functions that can support the stabilization of electrical power systems. This paper presents a fundamental study on the enhancement of transient stability in electrical power systems with increasing high share (i.e., above 50%) of power electronic interfaced generation. The wind generator type IV is taken as a representative form of power electronic interfaced generation, and the goal is to investigate how to mitigate the magnitude of the first swing while enhancing the damping of rotor angle oscillations triggered by major electrical disturbances. To perform such mitigation, this paper proposes a power-angle modulation (PAM) controller to adjust the post-fault active power response of the wind generator type IV, after a large disturbance occurs in the system. Based on a small size system, the PAM concept is introduced. The study is performed upon time-domain simulations and analytical formulations of the power transfer equations. Additionally, the IEEE 9 BUS system and the test model of Great Britain’s system are used to further investigate the performance of the PAM controller in a multi-machine context, as well as to perform a comparative assessment of the effect of different fault locations, and the necessary wind generators that should be equipped with PAM controllers.

Impacts of Grid Frequency Variation on Dynamic Performance of DFIG Based Wind Turbine

Wind energy is one of popular sources of renewable energy that massively used to generate electric power nowadays. Among wind generator technologies, Doubly Fed Induction Generator (DFIG) is placed as the first dominant wind generator type that is installed worldwide since 2004. Its popularity is due to the advantages of its capability to extract more energy compare to the fixed speed type. Moreover, it uses only one-third converter size which reduced the total construction cost compared to its closest rival, Full Converter Wind Turbine Generator Type. Although DFIG widely installed worldwide, it is in fact, very sensitive to the grid disturbances such as frequency variation. Based on IEEE standard for 60 Hz system, a power system should not be allowed to work in less than 59.3 Hz or more than 60.5 Hz. In this paper, DFIG-grid connected is extensively simulated in the condition of frequency variation that is carried out using Matlab/Simulink. The results show that some important parameters such as power output of the generator, voltage at point of common coupling, voltage at DC link and generator speed are experiencing significant rise/drop which in turn might damage the wind turbine generator.

Loading margin sensitivity analysis in systems with significant wind power generation penetration

The main objective of this paper is to evaluate the impacts in electrical networks, particularly on the voltage stability margins, due to the presence of Wind Generation (WG) and its intermittent characteristic. For this purpose, linear and quadratic sensitivities of the Loading Margin (LM) with relation to the wind speed are calculated, and then utilized to estimate possible alterations in the LM due to perturbations in the wind speed of the wind farms. To include the variable wind speed in the sensitivity analysis of the LM two types of wind generators are mathematically modeled and then incorporated into the power flow formulation. Lastly, three case studies are performed, where accurate estimates of the LM are obtained for wind speed perturbations in the wind farms, demonstrating the effectiveness of the proposed methodology and its potential to assist in the real-time operation and the operation planning of power systems with WG.

Impact of Wind Generation on Power Swing Protection

Large-scale integration of wind generation changes the power swing characteristics of a power system and may result in the misoperation of legacy power swing protection schemes. This paper presents a qualitative study on the impact of wind generation on power swing protection. The objective is to provide an understanding of the problem through case studies and present possible solutions and adjustments in protection schemes to ensure the efficiency of protection under large-scale integration of wind generation. The misoperation of power swing protection functions, namely power swing blocking and out-of-step tripping (OST), as a result of increased wind generation levels, are shown through case studies. It is also shown that the electrical center of a power system may move due to wind generation. In this case, it would be necessary to revise the optimal location of the OST protection. Finally, the impact of various factors, such as wind generator type, control scheme and fault-ride-through function, and wind generation level and capacity are investigated to determine the key features that need to be accounted for in practical protection studies.

Performance analysis of wind generators and PV systems in industrial small-scale applications

In this paper, some aspects of the performance of photovoltaic systems and wind generators are discussed. The performance of technologies for different types of wind generators is briefly explained, including the advantages and disadvantages of each type, and for different wind speeds. Technologies and techniques that improve the performance of different photovoltaic systems are also presented in a general way. In addition, a case study is presented to evaluate the use of wind generators and photovoltaic systems for small-scale industrial applications in the Tomar region (Portugal). The approach presented puts the focus on the small-scale applications for small/medium scale industries. These industries have a small/medium power consumption and most of them occupy limited spaces and the environmental conditions are those which exist in the place. The simulations show that there is a significant financial risk associated with the small-scale wind and photovoltaic systems. The purpose of this comparison is to ensure their technical and economic evaluation, leading to a better choice towards achieving zero net energy in buildings. The results obtained for the two technologies allow some important conclusions regarding their applications: photovoltaic systems have better performance than wind generators, photovoltaic systems have high-energy density, which leads to less need for space.

Experimental Evaluation of Wind Turbines Inverters on Generating Harmonic Currents

Abstract The search for alternative sources of energy, aimed at supplying the energy matrix, has shown a rapid increase in the use of wind energy worldwide. However, the interaction between wind farms and the electrical networks has shown itself to be an area of research interest. Among those phenomena that require evaluations by regulatory agencies, which in general aim at authorizing access to electric networks, emphasis is given to the following performance magnitudes: harmonic distortions, flicker, impacts on steady state voltages, transitory and dynamic performances, etc. The focus is here placed upon studies related to the estimation of individual and total harmonic distortions that are produced on the connection bus, these are frequently performed through use of computational resources. To this end, the studies are conducted on the basis of injecting individual harmonic current components produced by the generating units, which once adequately fixed, interact with the harmonic impedances determined by the composition of the internal network of the windfarm, along with the geometric locations that characterize the harmonic impedances of the connecting network. Therefore, such evaluations are performed based on equivalent Norton harmonics, which require, as a premise, the harmonic currents that are produced and injected. In this context, the present article is centered on specific issues linked to the qualitative and quantitative characterization of these harmonic currents, with emphasis on operational factors that exert influence on its orders and amplitudes. This work is conducted in order to clarify the origin and nature of the generated currents, the factors that influence such magnitudes, and finally, an evaluation of the theme through experimental studies performed for a laboratory installation aimed at emulating a full converter type of wind generator.

Comprehensive Protection Schemes for Different Types of Wind Generators

The fault characteristics for different types of wind generators are studied in this paper. Three types of wind generators are simulated within a microgrid that has the ability to connect and disconnect to a main grid. Types 1, 3, and 4 wind generators are simulated in both connected and islanded modes using MATLAB/Simulink software. The attributes of the current and voltage waveforms for each type at the time of the fault are detected. The simulation results show that each type of the wind generators contribute to the fault current in a way differs from the other type due to its configuration. The attributes of the fault characteristics reveals that careful design of the protection schemes, which protect the system, should be considered and special requirements on fault ride through capabilities are needed. Adequate protection schemes that suit the three types of the wind generators are proposed for islanded and grid-connected modes.

Design, Evaluation and Implementation of an Islanding Detection Method for a Micro-grid

Correct and fast detection of a micro-grid (MG) islanding is essential to the MG since operation, control, and protection of the MG depend on its operating mode i.e., an interconnected mode or islanding mode. This study describes the design, evaluation and implementation of an islanding detection method for an MG, which includes a natural gas-fired generator, a doubly fed induction generator type wind generator, a photovoltaic generator, and some associated local loads. The proposed method is based on the instantaneous active and reactive powers at the point of common coupling (PCC) of the MG. During the islanding mode, the instantaneous active and reactive powers at the PCC are constants, which depend on the voltage of the PCC and the impedance of the dedicated line. The performance of the proposed method is verified under various scenarios including islanding conditions for the different outputs of the MG, and fault conditions by varying the position, type, inception angle and resistance of the fault, using the PSCAD/EMTDC simulator. This paper also concludes by implementing proposed method into a TMS320C6701 digital signal processor. The results indicate that the proposed method successfully detects islanding for the MG in islanding conditions, and remains stable in fault conditions.

Damping tie-line power oscillations by modulation feedback of wind generators

This paper uses the power modulation capability of wind generators for damping tie-line power oscillations. The type of wind generator investigated is the permanent magnet synchronous generator (PMSG) connected to the power grid through a dc link. First, the paper develops a small-signal aggregate model for the wind generator. Subsequently, three modulation signals are investigated in order to provide effective power modulation: the PMSG speed reference, the rotor blade pitch angle and the dc link voltage. The latter is a novel approach that utilizes the energy stored in the dc link capacitors in order to modulate the power injected into the grid. The paper investigates the relation between the wind turbine and PMSG dynamics and the ability of each modulation loop to provide effective damping. A design method of the feedback loops based on the damping torque concept is demonstrated in the paper. Analytical results on a two-area power system show that wind generation can enhance the system dynamic stability by damping tie-line power oscillations. The analytical results are verified through time-domain simulations of a detailed 3-phase model of the system. The proposed dc link voltage modulation is shown to be a very effective means to provide power modulation in dynamic conditions.