Evaluation of Energy in Wind Turbine System Using Probability Distribution

Received Oct 2, 2017 Revised Dec 10, 2017 Accepted Jan 1, 2018 In this work, annual energy output of a variable speed wind turbine is analyzed using annual Weibull wind speed probability distribution function. The power coefficient variety with tip speed proportion in torque control district and pitch point variety for most extreme power yield from wind turbine are examined for distinguishing control framework parameters. The wind turbine power output and variation of power coefficient with tip speed ratio as well as pitch angle are examined / reported using annual Wei bull distribution function. Finally the variation of the estimated annual energy output of the given wind turbine with the mean wind speed is presented.


INTRODUCTION
The estimation of the annual energy output of a wind turbine to be installed at a particular site is very important in the assessment of economic feasibility of wind turbine installation [1], [2]. The output power of a wind power plant depends on many parameters (e.g. available wind speed resources, operational and power characteristics of the wind turbine).

BACKGROUND
Wind speed circulation investigation is required for choice of wind turbine and furthermore to design its control framework. The Weibull capacity is the one that most usually utilized for wind vitality forecast despite the fact that numerous numerical capacities have been proposed for wind speed likelihood appropriation capacities [3].

THE PROBLEM
The renewable energy is used in recent days especially solar is widely used. The solar power generation is only in day hours but in wind has generates power in both during day and night. The wind generates high power compared to other renewable energy.

PROPOSED SOLUTION
This paper introduces the portrays an approach of assessing the yearly vitality yield for a variable speed FRC wind turbine combined with a synchronous generator utilizing Weibull factual appropriation of wind speed Experimental Investigations on The Performance of A Solar Pond by using Encapsulated Pcm with Nano particles is discussed in [4]- [6]. Additionally in this work, variety of the yearly vitality yield with the mean wind speed is considered for augmenting the wind turbine control yield [7].

Figure 1. Typical FRC Wind Turbine Configuration
Wind turbine should be operated between cut-in wind speedand rated wind speed to extract the maximum power from thewind by keeping the pitch angle and the tip speed ratio at theiroptimum values [8].

WIND SPEED DISTRIBUTION
The wind data can be well fitted into Weibull distributionfunction. The expression of Weibull distribution functionwhich describes the probability of having a wind speed u during the year is expressed in (1) [9]. For the example, it is characterized with specified Weibullparameters: a = 8.3 ms−1, k = 1.9 and illustrated in Figure 2.

OPERATIONAL CHARACTERISTICS OF THE WIND TURBINE
The operation of the wind turbine is divided into fewregions, in order wind turbine to be operated to maximizethe power output while ensuring the safety of the system asillustrated in Figure 3 [8]. The output power of a wind turbine is expressed in (1) [8].
where, ρ : the air density (1.25 kg/m3) A : the area swept by the rotor in m2 u : the wind speed in ms−1 Cp: the power coefficient β : pitch angle in degrees λ : tip speed ratio In this work, MOD-2 wind turbine is utilized and after that the power coefficient (Cp) of MOD-2 wind turbine and the tip speed proportion of the turbine are communicated in (4) [10] and (5) separately.

OUTPUT CHARACTERISTICS OF THE SYNCHRONOUS GENERATOR
The shaft of the wind turbine is connected to the generatorthrough a gear box.Then at the generator, the transmittedmechanical energy is transfered into electrical energy througha magnetic medium Analysis on Solar Panel Crack Detection Using Optimization Techniques. Journal of Nano-& Electronic Physics is explained in [11]. Hence, the total power output from theturbine is not converted into electrical power as it is, due tothe mechanical and electrical losses in the energy conversionprocess [8]. In this work, typical power characteristic of an medium scale synchronousgenerator coupled with an AC-DC-AC link shown in Figure 4 is used [12].

ESTIMATION OF ANNUAL ENERGY OUTPUT OF THE WIND TURBINE
By in-cooperating the Weibull distribution, the energy contributionat wind speed u to the energy output of the systemcan be expressed in (2) [12].

P(u) = w(u)Pelectrical
(2) where, P(u) : Predicted energy output [Wh] w(u) : Probability of having a wind speed u Pelectrical: The output power of the synchronousgenerator at wind speed (u) For each set of Weibull parameters, the variation of theenergy contribution to the annual energy output is consideredwith the 1.0 ms−1 class intervals over the range of wind speed0 − 30 ms−1. Then the total annual energy generation of the system foreach set of Weibull parameters over the considered range ofmean speed, can be calculated by taking summation of theestimated energy output of the wind turbine of wind speed uover the range of possible wind speed 0−∞. The estimatedtotal annual energy output of the wind turbine over the rangeof mean wind speed 5 − 15 ms−1 for different shape factorsranging from 1.4 − 1.9 is illustrated in Figure 5.

CONCLUSION
This work introduces a method of estimating the annualenergy output for a variable speed FRC wind turbine coupledwith a synchronous generator using Weibull statistical distributionof wind speed. So as to survey the monetary attainability, operational execution of a twist turbine to be introduced, assurance of yearly vitality yield by the framework is essential. The wind turbine control yield and variety of energy coefficient with tip speed proportion and also pitch point are analyzed. It has been observed that the power regulation of thewind turbine system can be improved using pitch controllingabove the rated wind speed and below the cut-off wind speed.