WIND SPEED-TIP SPEED RATIO CONTROLLED WIND TURBINE APPARATUS
20230383725 · 2023-11-30
Assignee
Inventors
Cpc classification
F03D15/00
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F03D7/045
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F03D1/00
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F03D7/0224
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F03D7/0276
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F03D7/028
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F03D9/25
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F03D7/046
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
G05D13/66
PHYSICS
F05B2270/1033
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
International classification
F03D7/04
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F03D1/00
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F03D15/00
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F03D7/02
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F03D9/25
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
Abstract
A wind turbine control apparatus, method and non-transitory computer-readable medium are disclosed. The wind turbine control apparatus comprises a generator connected to a wind turbine with a drive train. The drive train comprises a rotor, a low speed shaft, a gear box, a high speed shaft, and a controller module. The controller module is configured to obtain a maximum power within a large range of varying wind velocities by operating the rotor at a neural network determined optimal angular speed for the current wind velocity.
Claims
1. A wind speed-tip speed ratio neural network (NN) trained wind turbine control apparatus, the neural network (NN) trained wind turbine control apparatus comprising: a controller module, the controller module comprising: a memory and a processor, wherein the processor includes instructions to control the wind turbine, wherein the wind turbine comprises a drive train comprising a generator, a high-speed shaft, a gearbox, a low-speed shaft, and a rotor and one or more blades connected to the rotor, wherein the gearbox connects the low-speed shaft to the high-speed shaft which is attached to the generator; wherein the blades have a length R equivalent to a radius of the wind turbine, wherein each blade of the one or more blades has a blade tip, a blade pitch angle, β, a blade swept area, and a tip speed, and a tip speed ratio (TSR), wherein the TSR is a ratio between a tangential speed of the blade tip and a wind velocity, wherein the controller module is configured to implement a machine learning neural network method to control a rotor speed of the wind turbine to achieve an optimum rotor speed and a maximum power as determined by the neural network at varying wind velocities, V.sub.w, the method including generating a data set including at least 120 samples each of wind velocities and tip speed ratios at wind speeds between 3 to 19.4 m/s; determining the maximum power and the optimum rotor speed for every sample of wind velocity in the data set; training a neural network (NN) model using the data set in which each sample of wind velocity in the data set is fed as an input and the determined optimum rotor speed and the determined maximum power are output from the NN model, testing the NN model with random input wind speed; and controlling the rotor of the wind turbine based on a current wind velocity and the optimum rotor speed determined by the NN model.
2. The wind speed-tip speed ratio neural network (NN) trained wind turbine control apparatus of claim 1, wherein the optimum rotor speed is given by:
ω.sub.opt=(λ.sub.optV.sub.w)/R where λ.sub.opt is an optimal tip speed ratio, and V.sub.w is a current wind velocity.
3. The wind speed-tip speed ratio neural network (NN) trained wind turbine control apparatus of claim 1, wherein the generator is a Permanent Magnet Synchronous Generator (PMSG).
4. The wind speed-tip speed ratio neural network (NN) trained wind turbine control apparatus of claim 1, wherein the maximum power (P.sub.max) at any given wind speed is given by:
P.sub.max=½ρAV.sub.w.sup.3C.sub.pmax(Δ,β) where ρ is an air density, A is a blade swept area, V.sub.w is wind velocity and C.sub.pmax is a power coefficient which is depicted by function of (λ,β) where λ is the tip speed ratio and β is the pitch angle, the function being
5. The wind speed-tip speed ratio neural network (NN) trained wind turbine control apparatus of claim 1, wherein the wind turbine achieves a maximum power output and an optimum rotor speed for a fluctuating wind speed between 3 m/s and 19.4 m/s.
6. The wind speed-tip speed ratio neural network (NN) trained wind turbine control apparatus of claim 1, wherein the trained wind turbine control apparatus stops the wind turbine only for wind speeds below 3 m/s and above 19.4 m/s.
7. The wind speed-tip speed ratio neural network (NN) trained wind turbine control apparatus of claim 1, wherein the controller changes the blade pitch angle only for wind speeds above 19.4 m/s.
8. The wind speed-tip speed ratio neural network (NN) trained wind turbine control apparatus of claim 1, wherein the controller adjusts the wind turbine to achieve the optimum rotor speed within 10 ms of a wind speed change.
9. A wind speed-tip speed ratio wind energy control method for a PMSG based wind turbine, wherein the PMSG based wind turbine comprises a controller module, and a drive train comprising a generator, a rotor, a gear box, high-speed shaft, and a low-speed shaft, and one or more blades; wherein the controller module comprising a memory and a processor; wherein the gearbox connects the low-speed shaft to the high-speed shaft which is attached to the generator, the method comprising: generating a data set including at least 120 samples each of wind velocities and tip speed ratios at wind speeds between 3 to 19.4 m/s; determining a maximum power and an optimum rotor speed (ω.sub.opt) for every sample of wind velocity in the data set; training a neural network (NN) model using the data set in which each sample of wind velocity in the data set is fed as an input and the determined optimum rotor speed and the determined maximum power are output from the NN model. testing the NN model with random input wind speed; and controlling the rotor of the PMSG based wind turbine based on a current wind velocity and the optimum rotor speed determined by the NN model.
10. The method of claim 9, wherein a feed forward back propagation method is used in the training of the neural network (NN) model.
11. The method of claim 9, wherein a radial basis function method is used in the training of the neural network (NN) model.
12. The method of claim 9, wherein the NN model determines that the maximum power (P.sub.max) at any given wind speed is given by:
P.sub.max=½ρAV.sub.w.sup.3C.sub.pmax(Δ,β) where ρ is air density, A is blade swept area, V.sub.w is wind velocity and C.sub.pmax is a power coefficient which is depicted by function of (λ, β), the function being
13. The method of claim 9, wherein the NN model determines the optimum rotor speed (ω.sub.opt) is given by:
ω.sub.opt=(λ.sub.optV.sub.w)/R where λ.sub.opt is optimal tip speed ratio, V.sub.w is wind velocity and R is a radius of the wind turbine.
14-20. (canceled)
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0038] A more complete appreciation of this disclosure and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein:
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DETAILED DESCRIPTION
[0064] In the drawings, like reference numerals designate identical or corresponding parts throughout the several views. Further, as used herein, the words “a,” “an” and the like generally carry a meaning of “one or more,” unless stated otherwise.
[0065] Furthermore, the terms “approximately,” “approximate,” “about,” and similar terms generally refer to ranges that include the identified value within a margin of 20%, 10%, or preferably 5%, and any values therebetween.
[0066] Aspects of this disclosure are directed to a neural network (NN) based wind turbine model for tracking maximum power in wind energy systems, particularly a Permanent Magnet Synchronous Generator (PMSG) based wind turbine. The present disclosure provides implementation of speed control for the PMSG based wind turbine using the NN based wind turbine model that effectively track estimated angular speed at maximum power therefor and thereby efficiently determines an optimum reference angular speed to drive a rotor of the PMSG based wind turbine.
[0067] Referring to
[0068] As illustrated in
[0069] The rotor 104 may be part of a horizontal access wind turbine (HAWT) or a vertical access wind turbine (VAWT) with HAWT being the dominant design configuration. The HAWT also allows for pitch and yaw control of the turbine which may be accomplished by a Yaw drive 130 and a yaw motor 132. VAWT has the advantage of allowing for heavy generating equipment to be mounted on the ground. Modern HAWT wind turbines used for electrical generation typically include 3 blades 106 as 3 blade HAWT systems have been found to be among the most efficient. Two bladed wind turbine are also efficient with three or four blades being marginally more efficient. However, the slightly higher efficiency is often weighed against the extra material, construction, and maintenance costs of a four or more blade system.
[0070] Curved blades 106 are typically used and are very similar to a long airplane wing (also known as an aero foil) which has a curved surface on top. The curved blade has air flowing around it with the air moving over the curved top of the blade faster than it does under the flat side of the blade, which makes a lower pressure area on top, and therefore, as a result, is subjected to aerodynamic lifting forces which create movement. The net result is a lifting force perpendicular to the direction of flow of the air over the turbines blade.
[0071] If the turbines propeller blades rotate too slowly, it allows too much wind to pass through undisturbed, and thus does not extract as much energy as it potentially could. If the propeller blade rotates too quickly, though, it appears to the wind as a large flat rotating disc, which creates a large amount of drag.
[0072] It's known that by slightly curving the turbine blade, they're able to capture 5 to 10 percent more wind energy and operate more efficiently in areas that have typically lower wind speeds. Then the optimal tip speed ratio, TSR, which is defined as the ratio of the speed of the rotor tip to the wind speed, depends on the rotor blade shape profile, the number of turbine blades, and the wind turbine propeller blade design itself.
[0073] Blades with tip speed ratios of six to nine utilizing an aero foil design are found to have negligible drag and tip losses,
[0074] The drive train 102 of a wind turbine is composed of the gearbox 110 and the generator 122, the necessary components that a turbine needs to produce electricity. The gearbox 110 is responsible for connecting the low-speed shaft 108 to the high-speed shaft 112 which in turn is attached to the generator 122. Assisted by a series of gears of varying sizes, the gearbox 110 converts the slow rotation of the blades 106—to the higher rotation, that the generator needs to begin producing electricity. The gearbox comprises the low speed shaft 108 connected to the rotor 104, a gear box 110 connected to the low speed shaft 108 from one side thereof, and a high speed shaft 112 connected to gear box 110 from other side The drive train 102 converts low-speed rotation of the rotor 104 (from wind energy) to high-speed rotation at the high speed shaft 112 using the gear box 110, such that the high-speed rotation of the high speed shaft 112 is connected to a generator 122 utilized for generating the power output, the generator connected to a controller module 124. Also shown in
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[0076] The blades 106 of the wind turbine 101 may capture the kinetic energy (KE) in the wind and translate it into rotational mechanical energy of the rotor 104, which in turn is converted into electrical energy by the generator 122 using the drive train 102. The KE of the moving air is:
where, ρ is an air density, V.sub.w is wind velocity (also referred to as “wind speed” for purposes of the present disclosure) and A is blade swept area. Herein, the air density (p) and the wind velocity (V.sub.w) are external factors; and the blade swept area (A) is the area through which the blades 106 of the rotor 104 of the wind turbine 101 spin, as seen when directly facing the center of the rotor 104. For example, a wind turbine 101 with radius 4.5 meters (the length of a single blade being the radius of the turbine) would have a wind swept area of π (radius) 2=3.14×20.25=63.585 m.sup.2. As may be understood, the expression in equation (1) clearly shows that as the wind velocity (V.sub.w) increases, the KE increases cubic times because of the cubic function of the wind velocity (V.sub.w).
[0077] From the above equation (1) above, the aerodynamic mechanical power (P.sub.m) for the wind turbine is given by:
P.sub.max=½ρAV.sub.w.sup.3C.sub.pmax(Δ,β) (2)
where, C.sub.p is a power coefficient which is depicted by function of (λ, β) with λ being tip speed ratio and β being blade pitch angle. Herein, the tip speed ratio (λ) also referred to as TSR is a ratio between the wind speed and the speed of tips of the blades 106 of the wind turbine 101; and the blade pitch angle (β), often shortened to pitch, refers to the angle between a chord line of the blade 106 and a plane of rotation of the rotor 104 in the wind turbine 101.
[0078] Further, as may be contemplated by a person skilled in the art, the relationship between the tip speed ratio (λ) and angular rotor speed (ω.sub.r) (in rad/sec) for the rotor 104 of the wind turbine 101 is given as:
where, R is radius of the wind turbine rotor 104. It may be appreciated that larger radius of the wind turbine rotor 104 (R) allow the wind turbine 101 to sweep more area, and thereby capture more wind and produce more power output.
[0079] Furthermore, the power coefficient (C.sub.p) being function of (λ, β) for the wind turbine 101 is evaluated as:
[0080] and, the tip speed ratio (λ) is estimated as:
[0081] Also, the relationship between mechanical torque (T.sub.m) and the aerodynamic mechanical power (P.sub.m) is given as:
[0082] Now, maximum power (P.sub.max) at any given wind speed is possible when maximum power coefficient (C.sub.pmax) is achieved at optimal tip speed ratio (λ.sub.opt). In particular, the maximum power coefficient (C.sub.pmax) is achieved at the optimal tip speed ratio (λ.sub.opt) with the blade pitch angle (β) being controlled only when the wind velocity (V.sub.w) exceeds the rated wind speed to maintain the rated active power of the wind turbine 101 and otherwise is kept constant at β=0° Herein, the maximum power (P.sub.max) at any given wind speed is given as:
[0083] Thereby, in the present embodiments, optimum rotor speed (ω.sub.opt) at the maximum power (P.sub.max) for the wind turbine 101 is given by:
[0084] Referring to
[0085] Also, as discussed, the mechanical power of the wind turbine is non-linear in nature due to intermittence of the wind speed. Referring to
[0086] In order to implement the MPPT technique, a model for the PMSG based wind turbine 101 needs to be developed. Herein, as the low speed shaft 108 is connected to the high speed shaft 112 via the gear box 110, therefore torque generated at the high speed shaft 112 near the PMSG 122 is given as T.sub.s operating at a speed given by ω.sub.ref. It may be noted that the PMSG 122 is connected to a current control pulse width modulation (PWM) inverter (not shown) for purposes of the present disclosure. The PMSG 122 is driven by the high speed shaft 112, as the entire dynamic model is implemented in dq-frame. The PMSG synchronous electrical model as given by the following equations:
where, V.sub.sd, V.sub.sq, I.sub.sd and I.sub.sq represent d-q axis stator voltages and currents, respectively; L s d and L.sub.sq represent inductances of the generator 122; P represents number of poles; ψ.sub.p represents permanent flux, R.sub.sa represents stator resistance; co s represents generator's electrical angular frequency; and T.sub.e represents electromagnetic torque.
[0087] Continuing with
[0088] Further, as illustrated in
[0089] The controller module 124 is configured to implement a machine learning neural network model (as represented by block 232); hereinafter, sometimes referred to as “neural network (NN) model” or “artificial neural network (ANN)” without any limitations. The machine learning neural network 232 is implemented to execute a machine learning neural network method. In particular, the controller module 124 is configured to implement the machine learning neural network method considering the wind speed (V.sub.w), as well as blade pitch angle (β), tip speed ratio (λ), radius of a wind turbine rotor (R), air density (ρ), maximum power coefficient (C.sub.pmax), optimum tip speed (or optimal tip speed ratio (λ.sub.opt)), maximum power (P.sub.max), gear ratio, stator phase resistance and armature inductance as input, and output a maximum power (P.sub.max) at varying wind speeds and a reference angular speed (i.e., optimum rotor speed (ω.sub.opt)) at varying wind speeds. It may be understood that, herein, the gear ratio is the gear ratio of the gear box 110; and the stator phase resistance and the armature inductance may be fixed properties of the generator 122 (as may be obtained from specification thereof).
[0090] The machine learning neural network 232 is developed by a series of algorithms that endeavors to recognize underlying relationships in a set of data through a process that mimics the way the human brain operates. The ANN 232 is an intelligent technique that evolved with the concept of biological neurons to perform complex computation. The ANN 232 has an ability to train from any data which is based on parallel processing by iteratively tuning of weights. In particular, a set of inputs is by means of weighting function is provided to hidden layer and then to output layer. The initial weight may be selected randomly by selecting maximum and minimum value of input. During the process of training, the weights are continuously updated for i.sup.th neuron. The weight equation is given in equation (12) below. Once the network is trained, then by subjecting any input the ANN can estimate the output accordingly with minimum error.
[0091] The implementation of the NN model 232 generally involves four major steps as listed below: [0092] i. Data generation: This is the primary step that involves the generation of offline data for a system with selected inputs and outputs to train the NN model 232. [0093] ii. Input/output selection: After data generation, candidate variables of the NN model 232 for input and output are selected based on the requirements of the present disclosure. [0094] iii. ANN architecture selection: Further, an architecture for the NN model 232 to be implemented may be selected depending on the requirements of the present disclosure, such as, but not limited to, Feed forward back propagation (FFBP) ANN and Radial basis function ANN. [0095] iv. ANN training and testing: Upon selection of the algorithm, the weights are determined to reduce or minimize the errors such as mean square error (MSE) or sum of squared errors (SSE). The selected inputs and outputs are provided to train the NN model 1232 thus modifying the NN model 232 data structure stored in the controller memory 230 After training, the NN model 232 is subjected to produce the outputs based on the selected test inputs.
[0096] In one or more embodiments, the feed forward back propagation (FFBP) method is used in the training of the neural network model 232. Referring to
[0097] As discussed, the present wind energy system 100 is formed by coupling the PMSG 122 with the wind turbine 101. The control strategy for the present wind energy system 100 with the PMSG 122 is performed by implementing the following steps: [0098] Generating data set [0099] NN training for WECS [0100] Testing of wind turbine NN model [0101] Speed control of wind energy PMSG system
[0102] Herein, the value(s) or range(s) for the given parameters that may be utilized are listed in Table 1 below.
TABLE-US-00001 TABLE 1 Control Parameters Wind Turbine Parameters Wind speed range (V.sub.w) 3 to 19.4 m/s Blade pitch angle (β) 0 Tip speed ratio (λ) 0.1~14 Radius of the wind turbine rotor (R) 37.5 m Air density (ρ) 1.225 kg/m.sup.3 Maximum power coefficient (C.sub.pmax) 0.4818 Optimum tip speed ratio (λ.sub.opt) 6.5 Maximum power (P.sub.max) @ 19.4 m/s 9.5 MW Gear ratio 75 PMSG parameters Stator phase resistance (R.sub.sa) 2.875 Ω Armature inductance (H) 0.00153 Simulation Parameters Operating wind speed 4-13 m/s Sampling time 2 μs.
[0103] Referring to
[0104] At step 502, the method 500 includes generating a data set, wherein the wind speed and the tip speed ratio are averagely sampled. In an example embodiment, the wind speed (V.sub.w) and the tip speed ratio (λ) are averagely sampled with 140 samples each, respectively. The range for the wind speed and the tip speed ratio are mentioned in Table 1 as provided above. Herein, the maximum power coefficient is achieved when the blade pitch angle (β) is set to zero (as discussed above).
[0105] At step 504, the method 500 includes calculating the maximum power (P.sub.max) and the optimum rotor speed (ω.sub.opt) for every sample of wind speed. From the equations (2) and (3) above, the mechanical power (P.sub.m) and the turbine rotational speed (ω.sub.r) are evaluated for each sample of wind speed. This generates a data set with a matrix 140 by 140 (or 19600) samples. Herein, each row corresponds to the mechanical power produced at one wind speed with 140 samples of the tip speed ratio. From each row, maximum value is selected as the maximum power (P.sub.max) and the optimum rotor speed (ω.sub.opt) for every sample of wind speed.
[0106] At step 506, the method 500 includes training the neural network (NN) model (such as, the NN model 232), wherein a sampled wind speed is fed as input while the optimum rotor speed (ω.sub.opt) and the maximum power (P.sub.max) are output from the neural network 232. That is, the NN model 232 is trained to obtain the optimum rotor speed (ω.sub.opt) and the maximum power (P.sub.max) from the wind energy system 100 based on the input wind speed. In an embodiment, the feed forward back propagation method is used in the training of the neural network model 232. That is, the NN model 232 is trained by using backpropagation algorithm (e.g., the FFBP model 400, as described above). In another embodiment, the radial basis function method is used in the training of the neural network model 232. The generated data set for wind is used as input to the NN model 232, and the data set generated for the maximum power (P.sub.max) and the optimum rotor speed (ω.sub.opt) is selected as target output. Referring to
[0107] At step 508, the method 500 includes testing the NN model 232. Referring to
[0108] At step 510, the method 500 includes controlling the PMSG based wind turbine 101 based on a current wind speed and the optimum rotor speed (ω.sub.opt) determined by the NN model 232. In the present embodiments, the wind turbine control module 124 drives the wind turbine 101 based on the maximum power (P.sub.max) or the reference angular speed (i.e., the optimum rotor speed (ω.sub.opt)) at varying wind speeds generated by the machine learning neural network method (as described above). For the speed control purposes, a control algorithm along with a power converter (PWM inverter, not shown) is implemented. Referring to
[0109] The controller module 124 may be implemented in the form of a PI (Proportional Integral) controller (with the two terms being interchangeably used), which corrects for error between the commanded set-point and the actual value based on some type of feedback. Herein, the PI controller 124 is fed by the error Δω=ω.sub.ref−ω.sub.PMSG between the reference angular speed (ω.sub.ref) and the PMSG output angular rotor speed (ω.sub.PMSG). With respect to the error in speed, the PI controller 124 generates q-axis current (i.sub.qref), while d-axis current (i.sub.dref) is set to zero as d-axis current control is adapted. This is implemented in order to control the grid side rectifier through the PI controller 124. Further, stator current (i.sub.abc) from the PMSG 122 is fed back to the PWM inverter and is compared with the reference current (i.sub.abcr). It may be contemplated that the electromagnetic torque (T.sub.e) may have a noisy behavior due to the presence of noise in the stator current.
Experimental Data
[0110] The PMSG based wind turbine 101 was designed and simulated in MATLAB/Simulink environment using the parameters in Table 1 above.
[0111] Further, a performance test of the wind energy system 100 under random varying input wind speed was performed. Herein, the NN model 232 for MPPT was adopted and tested under varying input wind speed. Referring to
[0112] Furthermore, based on the control strategy implemented as described in the preceding paragraphs, simulation is also performed to investigate the performance of the PMSG control based on the NN model 232 for the wind energy system 100. Referring to
[0113] Referring to
[0114] To test the performance of the proposed method 500, the wind energy control system 100 was simulated for 60 milliseconds (ms), with an input wind speed decreasing from 12.5 m/s to 12.26 m/s. Referring to
[0115] Further, to validate and confirm the robustness of the proposed method 500, the designed model was subjected to real time dataset of Eastern province (i.e. Hafar Al-Batin), KSA (28.268806° N, 44.203111° E). Monthly averaged wind speed for a year recorded at 80 meters height was used to quantify the performance of the designed control system under real conditions. The dataset was obtained from renewable resource atlas, King Abdullah city for Atomic and Renewable Energy (K.A. CARE). Referring to
[0116] Table 2 below shows the maximum power generated from the NN model 232, and theoretical and estimated power at given wind speed data of Hafar Al-Batin. During the month of June, the wind speed reached up to 9.23 m/s thereby increasing the mechanical power generated from the NN based wind turbine model to 1.025 MW. The proposed control system was found to be robust for a real time field wind data of Hafar Al-Batin with an error less than 0.27%.
TABLE-US-00002 TABLE 2 Maximum power generated from NN model and Theoretical calculated power at given wind speed of Hafar Al-Batin Mechanical Theoretical power Wind calculated generated speed Maximum from designed Error Month (m/s) power (MW) NN model (MW) (%) January 7.30 0.507 0.507 0.00 February 8.01 0.669 0.668 0.14 March 7.80 0.618 0.618 0.00 April 8.25 0.732 0.730 0.27 May 7.03 0.453 0.452 0.22 June 9.23 1.025 1.025 0.00 July 8.83 0.898 0.897 0.11 August 8.27 0.737 0.736 0.13 September 6.96 0.439 0.439 0.00 October 6.91 0.430 0.429 0.23 November 6.29 0.324 0.324 0.00 December 7.01 0.449 0.449 0.00
[0117] Referring to
[0118] Thereby, the present disclosure provides an intelligent control strategy for the PMSG based wind turbines. The proposed speed control of the PMSG was implemented with the help of the PI controller which was provided with the error of the reference shaft speed and the PMSG rotor speed. The MPPT was tracked and the PMSG generator 122 of the WECS 100 was capable to operate at reference speed as instructed by reference shaft speed generated by the NN model 232. The present wind turbine control module 124 and the method 500 achieve maximum power output under fluctuating wind speed with an error as low as 0.0025%. The robustness of the wind turbine control module 124 and the method 500 was confirmed as the PMSG rotor achieved the reference speed in less than 10 ms. The robustness of the proposed control system is further verified from the response of the angular speed and torque of the shaft rotor and the PMSG rotor, respectively, as both factor responded instantly to any change in the wind speed. The proposed NN-based control system was further validated with a real time dataset recoded in Eastern province (i.e. Hafar Al-Batin, 28.268806° N, 44.203111° E) of KSA. The present wind turbine control module 124 and the method 500 was found to be robust for a real time field wind data with an acceptable error as low as 0.27%. To the extent, the angular speed generated from the NN-based wind turbine model (that drives the PMSG rotor) effectively tracked the estimated angular speed at maximum power. Thus, the proposed NN-based intelligent control by the present wind turbine control module 124 and the method 500 may prove to be indispensable to design and specify wind turbine setup for optimum wind energy harvesting.
[0119] Next, further details of hardware description of the controller module 124 which may be implemented to control various functions and operation of the present wind energy control system 100 according to exemplary embodiments is described with reference to
[0120] Further, the claims are not limited by the form of the computer-readable media on which the instructions of the inventive process are stored. For example, the instructions may be stored on CDs, DVDs, in FLASH memory, RAM, ROM, PROM, EPROM, EEPROM, hard disk or any other information processing device with which the computing device communicates, such as a server or computer.
[0121] Further, the claims may be provided as a utility application, background daemon, or component of an operating system, or combination thereof, executing in conjunction with CPU (processor) 220 and an operating system such as Microsoft Windows 7®, Microsoft Windows UNIX®, Solaris®, LINUX®, Apple® MAC-OS and other systems known to those skilled in the art.
[0122] The hardware elements in order to achieve the computing device may be realized by various circuitry elements, known to those skilled in the art. For example, processor 220 may be a Xenon® or Core processor from Intel® of America or an Opteron® processor from AMD® of America, or may be other processor types that would be recognized by one of ordinary skill in the art. Alternatively, the processor 220 may be implemented on an FPGA, ASIC, PLD or using discrete logic circuits, as one of ordinary skill in the art would recognize. Further, processor 220 may be implemented as multiple processors cooperatively working in parallel to perform the instructions of the inventive processes described above.
[0123] The controller module 124 also includes a network controller 2306, such as an Intel Ethernet PRO network interface card from Intel Corporation of America, for interfacing with network 2360. As can be appreciated, the network 2360 can be a public network, such as the Internet, or a private network such as an LAN or WAN network, or any combination thereof and can also include PSTN or ISDN sub-networks. The network 2360 can also be wired, such as an Ethernet network, or can be wireless such as a cellular network including EDGE, 3G and 4G wireless cellular systems. The wireless network can also be Wi-Fi, Bluetooth, or any other wireless form of communication that is known.
[0124] The computing device further includes a display controller 2308, such as a NVIDIA GeForce GTX or Quadro graphics adaptor from NVIDIA Corporation of America for interfacing with display 2310, such as a Hewlett Packard HPL2445w LCD monitor.
[0125] The general purpose storage controller 2324 connects the storage medium disk 2304 with communication bus 2326, which may be an ISA, EISA, VESA, PCI, or similar, for interconnecting all of the components of the computing device. A description of the general features and functionality of the display 2310, the display controller 2308, storage controller 2324, network controller 2306, and the sound controller 2320 is omitted herein for brevity as these features are known.
[0126] In the present embodiments, the non-transitory computer readable medium having instructions stored therein that, when executed by one or more processors, cause one or more processors to perform a control method for wind turbine control. The method comprises generating a data set, wherein wind speed and tip speed ratio are averagely sampled. The method further comprises training a neural network model, wherein wind speed and tip speed ratio are fed as input, and a maximum power (P.sub.max) and an optimum rotor speed (ω.sub.opt) are output. The method further comprises testing of the neural network model with random input wind speed. The method further comprises speed control of a Permanent Magnet Synchronous Generator (PMSG) based wind turbine according to the P.sub.max from the neural network model.
[0127] In one or more exemplary embodiments, the instructions stored cause the one or more processors to calculate the maximum power (P.sub.max) at any given wind speed by:
P.sub.max=½ρAV.sub.w.sup.3C.sub.pmax(Δ,β)
where ρ is air density, A is blade swept area, V.sub.w is wind velocity and C.sub.pmax is a power coefficient which is depicted by function of (λ, β).
[0128] In one or more exemplary embodiments, the instructions stored cause the one or more processors to calculate the optimum rotor speed (ω.sub.opt) at the maximum power by:
where λ.sub.opt is optimal tip speed ratio, V.sub.w is wind velocity and R is the radius of the wind turbine rotor.
[0129] In one or more exemplary embodiments, the instructions stored therein cause the PMSG based wind turbine to achieve a maximum power output and an optimum reference angular speed under fluctuating wind speed between 3 m/s and 19.4 m/s.
[0130] In one or more exemplary embodiments, the instructions stored therein cause the PMSG based wind turbine to shut down for wind speeds below 3 m/s and above 19.4 m/s.
[0131] In one or more exemplary embodiments, the instructions stored therein cause the neural network model to be trained using a feed forward back propagation method.
[0132] In one or more exemplary embodiments, the instructions stored therein cause the neural network model to be trained using a radial basis method.
[0133] The exemplary circuit elements described in the context of the present disclosure may be replaced with other elements and structured differently than the examples provided herein. Moreover, circuitry configured to perform features described herein may be implemented in multiple circuit units (e.g., chips), or the features may be combined in circuitry on a single chipset.
[0134] The above-described hardware description is a non-limiting example of corresponding structure for performing the functionality described herein.
[0135] Obviously, numerous modifications and variations of the present disclosure are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein.