1MW vertical axis wind generating set

Abstract

The invention relates to the field of vertical axis wind driven generators, and provides a 1MW vertical axis wind driven generator set which comprises a wind wheel system and a power generation system used for converting kinetic energy captured by the wind wheel system into electric energy. The defects in the prior art are overcome, the blade tip speed ratio is dynamically adjusted to be controlled within the range of 5-7, the aerodynamic efficiency is optimized, and the power generation efficiency is improved. It is ensured that the wind wheel can obtain the optimal aerodynamic performance under different wind speed conditions, and therefore the power generation efficiency is improved; the blade angle is adjusted according to the wind direction, the blade position and the wind speed, the blades at different positions can obtain the maximum torque, and therefore the overall power generation efficiency is improved, and the defect that a traditional blade is fixed in angle is overcome.

Description

Technical Field

[0001] The present invention relates to the field of vertical axis wind turbines, and in particular to a 1MW vertical axis wind turbine generator set. Background Art

[0002] With the growing global demand for renewable energy, wind power generation is gaining increasing attention as a clean and sustainable form of energy. Small wind turbines, particularly in remote areas or those without electricity, are becoming an important means of addressing power supply challenges due to their ease of installation and low maintenance costs. Vertical-axis wind turbines, with their blades aligned horizontally with the main shaft and perpendicular to the ground, offer significant advantages in installation and maintenance, eliminating the need for a high tower. However, this design also imposes efficiency limitations. For example, when incoming air strikes the vertical-axis rotor, one side of the rotor experiences thrust from the wind, while the other side experiences resistance. This reduces effective wind-receiving performance, impacting overall power generation efficiency. Furthermore, the load-bearing structure of vertical-axis wind turbines requires special attention to ensure its stability and durability in harsh environments.

[0003] The vertical axis wind turbines currently on the market mainly have the following problems:

[0004] Since the torque magnitude and direction of the vertical axis wind wheel vary significantly at different positions, the aerodynamic efficiency is low, which affects the self-starting ability and load capacity.

[0005] Vertical axis wind turbines require a high starting wind speed and are difficult to start effectively under low wind speed conditions, which limits their application in light wind environments.

[0006] The blade design is complex and requires special design to adapt to the vertical airflow, which increases the difficulty of manufacturing and maintenance.

[0007] When running at low speed, vertical axis wind turbines may generate loud noise, affecting the user experience.

[0008] Based on the above problems, we propose a 1MW vertical axis wind turbine. Summary of the Invention

[0009] In response to the shortcomings of the existing technology, the present invention proposes a 1MW vertical axis wind turbine generator set, which significantly improves the power generation efficiency and reliability of the wind turbine by dynamically adjusting the tip speed ratio, optimizing the blade design, and improving the transmission system and control system.

[0010] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0011] A 1MW vertical axis wind turbine generator set, comprising: a wind wheel system and a power generation system for converting the kinetic energy captured by the wind wheel system into electrical energy, the optimization control process of the wind wheel system comprising the following steps:

[0012] Step 1: the wind wheel captures wind energy and calculates wind energy power;

[0013] Step 2: evaluate wind energy utilization rate;

[0014] Step 3: dynamically adjust the tip speed ratio to optimize aerodynamic efficiency;

[0015] Step 4: design the main drive shaft diameter based on maximum torque, and check according to torsional strength and stiffness;

[0016] Step 5: calculate the equivalent dynamic load according to the axial load and radial load, and match the ISO standard bearing.

[0017] Preferably, the wind energy power captured by the wind wheel is calculated by converting the wind energy into kinetic energy in the wind turbine, and the flow of air, i.e. wind, drives the wind wheel to rotate, and the wind energy power formula is:

[0018] P = W / t

[0019] m = pV

[0020] V = SL

[0021]

[0022] According to the above: Where P is the wind energy power, indicating the rate of wind energy conversion into mechanical or electrical energy, W is the wind energy, indicating the energy contained in the wind, t is the time, indicating the duration of the wind energy action, m is the air mass, indicating the air mass flowing through the wind wheel, p is the air density, indicating the mass of air per unit volume, v is the wind speed, i.e. the speed of air flow, S is the wind wheel swept area, indicating the area covered by the wind wheel when rotating, and L is the wind wheel radius, i.e. the distance from the center of the wind wheel to the edge.

[0023] Preferably, the wind energy utilization rate is evaluated, and the wind energy utilization rate C is obtained by converting the wind energy into the mechanical energy of the wind wheel. p The formula is: Where the wind energy utilization coefficient C p Indicates the wind turbine efficiency parameter; P m The mechanical power output by the wind turbine; P w The wind energy input by the wind turbine.

[0024] Preferably, the tip speed ratio is dynamically adjusted, wherein the tip speed ratio λ is a key measure of the performance of the wind wheel, and the tip speed ratio λ of the wind wheel at different wind speeds is measured by the ratio of the circumferential speed of the blade to the wind speed, and the calculation formula is: Where n is the rotational speed of the wind wheel, ω is the angular velocity of the wind wheel; R is the radius of the wind wheel, and v is the wind speed.

[0025] The minimum diameter of the main transmission shaft is preferably estimated according to the torsional strength of the hollow main shaft:

[0026]

[0027] Where A is the material coefficient, d is the diameter of the shaft end; n is the working rotational speed of the shaft, P is the power transmitted by the shaft, and a is the ratio of the inner diameter d1 to the outer diameter d of the hollow shaft, a = d1 / d;

[0028] The diameter is calculated according to the torsional stiffness of the main transmission shaft:

[0029]

[0030] Where B is the stiffness coefficient, and if there are key grooves on the cross section of the main transmission shaft, the diameter of the main transmission shaft is increased by

[0031] The safety factor of the main transmission shaft is checked; the maximum torque of the main transmission shaft is the torque borne under the maximum wind speed:

[0032] The safety factor when only considering the torsional effect is:

[0033] Where τ -1 is the material torsional fatigue limit under symmetric cyclic stress; K τ is the effective stress concentration coefficient when torsion; β is the surface quality coefficient; ε τ is the size influence coefficient when torsion; τ a , τ m are the stress amplitude and average stress of the torsional stress; ψ τ is the average profit conversion coefficient of the material torsion.

[0034] The equivalent dynamic load of the bearing is preferably calculated, and the axial load is:

[0035] F a = (m1 + m2 + m3 + n x m4) x g

[0036] Where m1 is the rotor mass; M2 is the transmission mechanism mass; M3 is the generator rotor mass; n is the safety factor; M4 is the dynamic additional mass; and g is 9.81 m / s 2 ;

[0037] The radial load is calculated according to the set working condition, and according to the Bernoulli equation, the pressure of the airflow acting on the blade is: P = 0.5 p v 2

[0038] The total force acting on the blade is: Fr = dPS, where d is the number of corresponding blades;

[0039] The formula for calculating the equivalent dynamic load of the bearing is: P = XF r + YF a , where X and Y are the radial dynamic load coefficient and the axial dynamic load coefficient, respectively, and then the load P is calculated;

[0040] The bearing rated dynamic load is calculated according to the following formula: , where: C is the basic rated dynamic load calculation value, f n is the speed factor; f m is the torque load factor, f d is the impact load factor; f T is the temperature factor; f h is the life factor, and P is the equivalent dynamic load; the C value is obtained by substituting the data into the above formula, and compared with the C r value of the corresponding type of bearing, which is less than C r ;

[0041] The bearing life is calculated as follows:

[0042]

[0043] , where: f T is the temperature factor, f d is the impact load factor, C is the rated dynamic load, n is the speed of the bearing, and P is the equivalent dynamic load.

[0044] Preferably, the power generation system comprises a silicon rectifier alternator, which is composed of a rotor, a stator, a rectifier, an end cover and a silicon diode rectifier, and the alternator is connected with a wind wheel through a main transmission shaft; the main transmission shaft and the alternator are connected by a conical pin sleeve coupling.

[0045] Preferably, the rectifier is a three-phase bridge full-wave rectifier circuit composed of six silicon diodes, which converts three-phase alternating current into direct current; three of the diodes are positive diodes and are press-fitted on an insulating element plate; the other three are negative diodes and are press-fitted on a non-insulating element plate or an end cover.

[0046] Preferably, the end cover comprises a driving end cover and a brush end cover; the brush end cover is provided with a brush holder and two insulating brushes, which are in contact with a rotor slip ring through brush springs; the rectifier assembly is installed on the driving end cover.

[0047] Preferably, the blades of the wind wheel adopt H-shaped or Ф-shaped airfoils.

[0048] The ratio of the total area of the airfoils to the area through which the wind passes the wind wheel is called the solidity ratio, which is a reference data of the wind turbine. The formula for calculating the solidity of the vertical axis wind turbine is:

[0049] σ=NCL / 2RL=NC / 2R

[0050] The lift-type vertical axis wind turbine rotor, C is a wing piece chord, N is the number of wing pieces, R is the radius of the wind turbine, L is the length of the wing piece, and sigma is the solidity ratio; the wing piece section adopts a main beam skin type structure, the surface material is aluminum alloy, the main beam adopts hard aluminum material, forms an O-shaped structure, and the hollow part of the wing piece is filled with polyurethane.

[0051] The application provides a 1MW vertical axis wind turbine generator set.

[0052] By dynamically adjusting the tip speed ratio to be controlled in the range of 5 to 7, the aerodynamic efficiency is optimized, and the wind turbine can obtain the best aerodynamic performance under different wind speed conditions, so that the power generation efficiency is improved;

[0053] The H-shaped or Φ-shaped wing piece is adopted, the shape and structure of the blade are optimized, the wind energy capturing capacity is improved,

[0054] The blade angle is adjusted according to the wind direction, the blade position and the wind speed, so that the blades at different positions can obtain the maximum torque, and the overall power generation efficiency is improved, and the defects of the traditional fixed angle of the blade are overcome,

[0055] The minimum diameter of the main transmission shaft is calculated based on the maximum torque requirement, the torsional strength and the stiffness are double-checked, the stability and reliability of the main transmission shaft under high load conditions are ensured, in addition, by reasonably selecting the bearing type (such as an angular contact ball bearing), the radial and axial loads can be simultaneously borne, and the overall performance of the system is improved;

[0056] By adopting the coaxial structure design, the relative movement between the wind turbine shaft and the generator shaft is avoided, and the failure is reduced. At the same time, by optimizing the blade width and structure, the self-starting ability and wind resistance of the wind turbine are improved. BRIEF DESCRIPTION OF DRAWINGS

[0057] Figure 1 The figure is a wind speed curve of the wind turbine speed and output power of the application;

[0058] Figure 2 The figure is a wing piece section view of the application;

[0059] Figure 3 The figure is a main shaft schematic view of the application;

[0060] Figure 4 The figure is a schematic view of the installation position of bearing 1 of the application;

[0061] Figure 5 The figure is a schematic view of the installation position of bearing 2 of the application;

[0062] Figure 6 Figure 1 is a schematic diagram of a conical pin sleeve coupling of the present invention;

[0063] Figure 7 Figure 2 is a schematic diagram of the kinetic energy of air flow of the present invention; DETAILED DESCRIPTION

[0064] In order to make the purposes, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be described clearly and completely below with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are some but not all of the embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the present invention.

[0065] Reference is made to the drawings Figures 1-7 A 1MW vertical axis wind turbine generator set, comprising: a wind wheel system and a power generation system for converting the kinetic energy captured by the wind wheel system into electrical energy, the optimization control process of the wind wheel system comprising the following steps:

[0066] Step 1: the wind wheel captures wind energy and calculates wind energy power;

[0067] Step 2: evaluate wind energy utilization rate;

[0068] Step 3: dynamically adjust the tip speed ratio to optimize aerodynamic efficiency;

[0069] Step 4: design the main drive shaft diameter based on maximum torque, and double check according to torsional strength and stiffness;

[0070] Step 5: calculate the equivalent dynamic load according to the axial load and radial load, and match the ISO standard bearing.

[0071] As Figure 7 shown, the calculation of wind energy power captured by the wind wheel converts wind energy into kinetic energy in the wind turbine, and the flow of air, i.e. wind, drives the wind wheel to rotate, and the wind energy power formula is:

[0072] P = W / t

[0073] m = pV

[0074] V = SL

[0075]

[0076] According to the above, we can get: Where P is the wind power, indicating the rate of wind energy converted into mechanical or electrical energy, with the unit of watt (W). W is the wind energy, indicating the energy contained in the wind, with the unit of joule (J). t is the time, indicating the duration of wind energy acting, with the unit of second (s). m is the air mass, indicating the air mass flowing through the wind wheel, with the unit of kilogram (kg). p is the air density, indicating the mass of air per unit volume, with the unit of kilogram per cubic meter (kg / m 3 ). v is the wind speed, i.e. the speed of air flow, with the unit of meter per second (m / s). S is the swept area of the wind wheel, indicating the area covered by the wind wheel when rotating, with the unit of square meter (m 2 ).

[0077] The wind energy utilization rate is evaluated, and the wind wheel converts the wind energy into the mechanical energy of the wind wheel, and the wind energy utilization rate C p is obtained. The formula is: Where the wind energy utilization coefficient C p represents the wind turbine efficiency parameter; P m is the mechanical power output by the wind turbine; P w is the wind energy input by the wind turbine.

[0078] At present, the wind energy utilization rate of most vertical axis wind wheels can reach about 0.4, and if the wind energy utilization rate is calculated at 0.4, the wind wheel power is 1000W, and the wind energy is 1000 / 0.4=2500W.

[0079] According to the above formula, S 3 v can be obtained. =2500x2 / p=5000 / 1.25=4000, if the rated wind speed is 20m / s, S=0.5m 2 , obviously the lower the rated wind speed is set, the larger S will be; S=2xrXL, S is the swept area of the wind, r is the distance of the blade from the shaft and also the radius of the wind wheel, and L is the height of the blade.

[0080] If the wind wheel power reaches 1000W, the swept area of the wind cannot be less than 0.5m 2 , then if r is 0.25m, L is 1m.

[0081] The torque of the wind turbine is:

[0082]

[0083] The tip speed ratio is dynamically adjusted, where the tip speed ratio λ is the key to measure the performance of the wind wheel. The tip speed ratio λ of the wind wheel at different wind speeds is measured by the ratio of the circumferential speed of the blade to the wind speed, and the calculation formula is: Where: n is the rotation speed of the wind wheel, r / s; ω is the angular velocity of the wind wheel, rad / s; R is the radius of the wind wheel, m; v represents the wind speed.

[0084] The tip speed ratio determines the power of the wind rotor. For a fixed pitch wind rotor, its speed increases with the increase of wind speed. In this case, the output power (proportional to the cube of the wind speed) also increases.

[0085] However, the increase in output power does not mean that the wind energy utilization rate also increases. Generally speaking, the curve of tip speed ratio and wind energy utilization rate is approximately an inverted parabola.

[0086] According to the tip speed ratio λ and C p The relationship between p The relationship between the blade tip speed ratio and the output power is that when the wind speed is fixed, different rotation speeds correspond to different blade tip speed ratios, that is, different C p The value also corresponds to different output powers. If different wind speeds are set, the relationship between the output power and speed of the wind turbine at different wind speeds can be obtained, such as Figure 1 As shown, it can be seen that at a certain wind speed, the output mechanical power of the wind turbine varies with the rotational speed. There is an optimal rotational speed at which the wind turbine outputs the maximum mechanical power. Its relationship with the wind speed is the optimal tip speed ratio relationship. At different wind speeds, there is an optimal rotational speed that enables the wind turbine to output the maximum mechanical power, thereby obtaining a maximum output mechanical power curve. At any point on this curve, the relationship between the rotational speed and wind speed is the optimal tip speed ratio relationship. Reasonable selection of the optimal tip speed ratio can make the wind rotor power reach its peak value; generally, the vertical axis wind rotor tip speed ratio is selected between 4 and 8, and 6 is recommended. The lower the speed, the lower the noise, but it is also more difficult to increase the power.

[0087] like Figure 3 As shown, the minimum diameter of the main drive shaft is estimated based on the torsional strength of the hollow main shaft:

[0088]

[0089] Where A is the material coefficient, d is the shaft end diameter, mm; n is the shaft operating speed, r / min; P is the power transmitted by the shaft, kW; α is the ratio of the inner diameter d1 to the outer diameter d of the hollow shaft, α = d1 / d;

[0090] Calculate the diameter based on the torsional stiffness of the main drive shaft:

[0091]

[0092] Where B is the stiffness coefficient. If there is a keyway on the cross section of the main transmission shaft, the main transmission shaft diameter will be increased and the main transmission shaft safety factor will be checked. The maximum torque of the main transmission shaft is the torque it can withstand at the maximum wind speed:

[0093] The safety factor only considering the torsional resistance is:

[0094] Where τ -1 is the torsional fatigue limit of the material under symmetrical cyclic stress, Mpa, K τ is the effective stress concentration factor during torsion; β is the surface quality coefficient; ε τ is the size effect coefficient during torsion; τ a , τ m are the stress amplitude and average stress of the torsional stress; ψ τ is the average profit conversion coefficient of the material torsion.

[0095] If τ -1 = 115, K τ = 1.8, β = 0.44, ε τ = 0.89, ψ τ = 0.21, substituting into the above formula The safety factor S τ = 5.5 can be obtained, then according to the material quality mark of the steel, check the table to see if the safety factor meets the requirement, if not, increase the diameter of the main shaft.

[0096] The equivalent dynamic load of the bearing is calculated, since the wind turbine not only bears the torsion of the wind wheel, but also bears a certain bending moment in the direction of the airflow, the angular contact ball bearing can not only bear the radial force, but also bear a certain radial load, therefore two angular contact ball bearings are installed on the main transmission shaft; the installation position of the angular contact ball bearing 1 is shown as Figure 4 , and the installation position of the angular contact ball bearing 2 is shown as Figure 5 .

[0097] The axial load is:

[0098] F a = (m1+m2+m3+n×m4)×g

[0099] In the formula, m1 is the rotor mass; M2 is the transmission mechanism mass; M3 is the generator rotor mass; n is the safety factor; M4 is the dynamic additional mass; g is 9.81 m / s 2 ;

[0100] The radial load is calculated according to the set working condition (air density ρ = 1.25 kg / m 3 , design wind speed v = 10 m / s, single blade area S = 4 × 0.6 = 2.4 m 2 ), according to Bernoulli equation, the pressure of the airflow acting on the blade is: P = 0.5 ρv 2

[0101] The total force acting on the blade is: Fr = dPS, where d is the number of corresponding blades;

[0102] The formula for calculating the equivalent dynamic load of the bearing is: P = XF r + YF a , where X and Y are the radial dynamic load coefficient and the axial dynamic load coefficient, respectively, and then the load P is calculated.

[0103] The bearing rated dynamic load is calculated as follows: , where: C is the basic rated dynamic load calculation value, N; f n is the speed factor; f m is the torque load factor, f d is the impact load factor; f T is the temperature factor; f h is the life factor, P is the equivalent dynamic load; substitute each data into the above formula to get the value of C, and compare it with the C r value of the corresponding type of bearing. If it is less than C r , it is acceptable.

[0104] Calculate the bearing life:

[0105]

[0106] , where: f T is the temperature factor, f d is the impact load factor, C is the rated dynamic load; n is the speed of the bearing, r / min; P is the equivalent dynamic load.

[0107] When the shaft diameter d = 30 mm, the rated torque T = 4.3 Nm;

[0108] Axial load:

[0109] F a = (m1 + m2 + m3 + n x m4) x g

[0110] , where m1 is the rotor mass ≈ 85 kg; M2 is the transmission mechanism mass ≈ 32 kg;

[0111] M3 is the generator rotor mass ≈ 28 kg; n is the safety factor, taken as 1.5; M4 is the dynamic additional mass ≈ 15 kg; g is 9.81 m / s 2 ;

[0112] Substituting the calculation gives: F a = (85 + 32 + 28 + 1.5 x 15) x 9.81 ≈ 1680 N

[0113] The radial load is calculated according to the air density p = 1.25 kg / m 3 , the design wind speed v = 10 m / s, the single blade area S = 4 x 0.6 = 2.4 m2 According to Bernoulli equation, the pressure of the airflow acting on the blade is calculated as:

[0114] P = 0.5 p v 2 = 0.5 x 1.25 x 10 2 = 62.5 Pa

[0115] The total force acting on the blade is:

[0116] F r = g P S = 3 x 62.5 x 4 x 0.6 = 450 N

[0117] where g is 3 corresponding to the number of blades;

[0118] When ISO 281 standard is adopted: Parameter values: for deep groove ball bearing 6206: X = 0.56, Y = 1.45 (when F a / F r >e = 0.26)

[0119] Calculation verification: F a / F r = 1680 / 450 ≈ 3.73 > 0.26, so: P = 0.56 x 450 + 1.45 x 1680 ≈ 252 + 2436 = 2688 N

[0120] Bearing rated dynamic load; where: f n (speed factor): assumed to be a certain value, such as 1.0 (in practice, it needs to be determined according to specific circumstances);

[0121] f m (moment load factor): according to the description, select 2;

[0122] f T (temperature factor): assumed to be 1.0 (as no specific value is given);

[0123] f h (life factor): assumed to be 0.9 (in practice, it needs to be determined according to the expected life);

[0124] p (equivalent dynamic load): assumed to be 1000 N;

[0125] Calculation process: C = (1.0 * 2 * 1000 N) / 0.9 * 1.0 ≈ 2222.22 N;

[0126] Result comparison: compare the calculated C value with the nominal C value of the corresponding type of bearing in the manual, if less than the nominal value, it meets the use conditions;

[0127] The power generation system comprises a silicon rectification alternator composed of a rotor, a stator, a rectifier, an end cover and a silicon diode rectifier, and the alternator is connected with a wind wheel through a main transmission shaft; the main transmission shaft and the alternator are connected through a conical pin sleeve coupling, as shown in Figure 6

[0128] The rectifier is a three-phase bridge full-wave rectification circuit composed of six silicon diodes, which converts three-phase alternating current into direct current; three diodes are positive diodes and are press-fitted on an insulating element plate; the other three are negative diodes and are press-fitted on a non-insulating element plate or an end cover.

[0129] The three-phase alternating current generated by the alternator is converted into direct current through three-phase bridge full-wave rectification of the rectifier;

[0130] The rectifier is a three-phase bridge full-wave rectification circuit composed of six silicon diodes, which converts three-phase alternating current into direct current; three diodes are positive diodes and are press-fitted on an insulating element plate; the other three are negative diodes and are press-fitted on a non-insulating element plate or an end cover.

[0131] The end cover comprises a driving end cover and a brush end cover; the brush end cover is provided with a brush holder and two insulating brushes, which are in contact with the rotor slip rings through brush springs; the rectifier assembly is installed on the driving end cover.

[0132] The end cover comprises a driving end cover and a brush end cover, both of which serve as front and rear supports of the alternator;

[0133] The brush end cover is provided with a brush holder and two insulating brushes, which are in contact with the two slip rings on the rotor shaft through brush springs; the leads of the brushes are connected with two magnetic field connection posts on the brush end cover (for an outer-ironing alternator) or one is connected with a magnetic field connection post and the other is internally ironed (for an inner-ironing alternator); the rectifier assembly of the alternator is also installed on the driving end cover, which is conducive to maintenance.

[0134] The blades of the wind wheel adopt H-shaped or Φ-shaped wings; the wings are rotated by the pressure difference generated when the airflow passes through,

[0135] The ratio of the total area of the wings to the area of the wind passing through the wind wheel (wind wheel swept area) is called the solidity ratio (volume ratio), which is a reference data of the wind turbine, and the wing solidity calculation formula of the vertical axis wind turbine is:

[0136] ​σ = NCL / 2RL = NC / 2R

[0137] The wind wheel of the lift-type vertical axis wind power generator, C is the wing piece chord length, N is the wing piece number, R is the wind wheel radius, L is the wing piece length, and σ is the solidity ratio; the wing piece section adopts the main beam skin type structure, the surface material is aluminum alloy, the main beam adopts hard aluminum material, forms an O-shaped structure, and the hollow part of the wing piece is filled with polyurethane,

[0138] The main beam and the aluminum alloy skin are connected through direct welding, after the connection is completed, the polyurethane is filled in the open-web structure, and the filling and forming are completed through direct foaming, so that the integrity and sealing performance of the structure are ensured, the cross section form is as shown in Figure 2 Thus, the basic parameters of the wind power generator can be determined, as shown in the table.

[0139]

[0140] Reasonable selection of the solidity ratio is to minimize the cost of manufacturing the wing piece under the condition of ensuring the aerodynamic characteristics of the wind wheel, in order to maximize the dynamic efficiency, the airfoil characteristics should have the following requirements: large lift coefficient slope;

[0141] Small drag coefficient;

[0142] The drag coefficient is symmetrical to the zero-lift angle.

[0143] The drag coefficient of NACA0012 is small, and the symmetrical airfoil of NACA0012 with lower drag coefficient is selected;

[0144] Since NACA0012 is a symmetrical airfoil, c is the chord length (the chord length is 1.00); x is the chord length coordinate (the unit is x / c); y is the distance between the airfoil and the chord corresponding to the x position (the unit is y / c).

[0145] The solidity ratio is preferably selected in the range of 0.5-0.6, and thus the chord length of the wind wheel wing piece can be obtained:

[0146]

[0147] The wing piece chord length that can be used is 0.4m,

[0148] It is to be noted that, in the present text, relational terms such as first and second and the like can be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises", "comprising", or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can also include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element proceeded by "comprises... a" does not, without more constraints, exclude the existence of additional identical elements in the process, method, article, or apparatus that comprises the element.

[0149] The above examples are merely used to illustrate the technical solutions of the present application, but not to limit it; although the present application has been described in detail with reference to the foregoing examples, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing examples, or make equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A 1MW vertical axis wind turbine generator set, characterized in that: include: A wind rotor system and a power generation system for converting kinetic energy captured by the wind rotor system into electrical energy, wherein the optimization control process of the wind rotor system includes the following steps: Step 1: The wind wheel captures wind energy and calculates wind power; Step 2: Evaluate wind energy utilization; Step 3: Dynamically adjust the tip speed ratio to optimize aerodynamic efficiency; Step 4: Design the main drive shaft diameter based on the maximum torque, and double-check the torsional strength and stiffness; Step 5: Calculate the equivalent dynamic load based on the axial load and radial load and match the ISO standard bearing.

2. A 1MW vertical axis wind turbine generator set according to claim 1, characterized in that: Calculate the wind power captured by the wind rotor. The wind energy is converted into kinetic energy by the wind rotor in the wind turbine. The flow of air, that is, wind, drives the wind rotor to rotate. The wind power formula is: P=W / t m=ρV V=SL According to the above, we can get: Among them, P is wind power, which indicates the rate at which wind energy is converted into mechanical energy or electrical energy; W is wind energy, which indicates the energy contained in the wind; t is time, which indicates the duration of wind energy action; m is air mass, which indicates the mass of air flowing through the wind rotor; ρ is air density, which indicates the mass of air per unit volume; v is wind speed, that is, the speed of air flow; S is the swept area of ​​the wind rotor, which indicates the area that can be covered when the wind rotor rotates; L is the radius of the wind rotor, which is the distance from the center of the wind rotor to the edge.

3. A 1MW vertical axis wind turbine generator set according to claim 1, characterized in that: To evaluate the utilization rate of wind energy, the wind wheel converts wind energy into mechanical energy of the wind wheel, and the wind energy utilization rate C is obtained. p The formula is: The wind energy utilization coefficient C p Represents the wind turbine efficiency parameter; P m P is the mechanical power output by the wind turbine; w Wind energy input to wind turbines.

4. A 1MW vertical axis wind turbine generator set according to claim 1, characterized in that: Dynamically adjust the tip speed ratio, where the tip speed ratio λ is the key to measuring the performance of the wind rotor. The tip speed ratio λ of the wind rotor at different wind speeds is measured by the ratio of the circumferential speed of the blade to the wind speed. The calculation formula is: Where: n is the rotation speed of the wind wheel, ω is the angular velocity of the wind wheel; R is the radius of the wind wheel, and v represents the wind speed.

5. A 1MW vertical axis wind turbine generator set according to claim 1, characterized in that: The minimum diameter of the main drive shaft is estimated based on the torsional strength of the hollow main shaft: Where A is the material coefficient, d is the diameter of the shaft end; n is the operating speed of the shaft, P is the power transmitted by the shaft, α is the ratio of the inner diameter d1 of the hollow shaft to the outer diameter d, α = d1 / d; Calculate the diameter based on the torsional stiffness of the main drive shaft: Where B is the stiffness coefficient. If there is a keyway on the cross section of the main transmission shaft, the diameter of the main transmission shaft will be increased. Check the safety factor of the main transmission shaft; the maximum torque of the main transmission shaft is the torque it can withstand at the maximum wind speed: The safety factor when only torsion rejection is considered is: where τ -1 K is the torsional fatigue limit of the material under symmetrical cyclic stress; τ is the effective stress concentration factor in torsion; β is the surface quality coefficient; ε τ is the dimensional influence coefficient during torsion; τ a , τ m is the stress amplitude and average stress of torsional stress; ψ τ The average profit conversion coefficient for material reversal.

6. A 1MW vertical axis wind turbine generator set according to claim 1, characterized in that: Calculate the equivalent dynamic load and axial load of the bearing: F a =(m1+m2+m3+n×m4)×g Where m1 is the rotor mass; M2 is the transmission mechanism mass; M3 is the generator rotor mass; n is the safety factor; M4 is the dynamic additional mass; g is 9.81 m / s 2 ; The radial load is calculated according to the set working conditions. According to the Bernoulli equation, the pressure of the airflow on the blade is: P = 0.5ρv 2 The total force acting on the blade is: F r =dPS, where d is the number of corresponding leaves; The calculation formula for the equivalent dynamic load of the bearing is: P = XF r +YF a , where X and Y are radial dynamic load coefficient and axial dynamic load coefficient respectively, and then calculate the load P; The dynamic load rating of the bearing is calculated according to the following formula: Where: C is the calculated value of basic rated dynamic load, f n is the speed factor; f m is the moment load factor, f d is the impact load factor; f T is the temperature factor; f h is the life factor, P is the equivalent dynamic load; Substitute each data into the above formula to get the C value, and compare it with the C value of the corresponding bearing model. r Value comparison, less than C r That's it; Calculating bearing life: Where: f T is the temperature factor, f d is the impact load factor, C is the rated dynamic load, n is the speed of the bearing, and P is the equivalent dynamic load.

7. A 1MW vertical axis wind turbine generator set according to claim 1, characterized in that: The power generation system includes a silicon rectifier AC generator, which consists of a rotor, a stator, a rectifier, an end cover and a silicon diode rectifier. The generator is connected to the wind wheel through a main drive shaft; the main drive shaft and the generator are connected by a tapered pin sleeve coupling.

8. A 1MW vertical axis wind turbine generator set according to claim 7, characterized in that: The rectifier is a three-phase bridge full-wave rectifier circuit, consisting of 6 silicon diodes, which converts three-phase alternating current into direct current; 3 of the diodes are positive diodes, which are pressed onto an insulating component board; the other 3 are negative diodes, which are pressed onto a non-insulating component board or end cover.

9. A 1MW vertical axis wind turbine generator set according to claim 7, characterized in that: The end cover includes a driving end cover and a brush end cover; the brush end cover is equipped with a brush holder and two insulating brushes, which are in contact with the rotor slip ring through a brush spring; and the rectifier assembly is installed on the driving end cover.

10. A 1MW vertical axis wind turbine generator set according to claim 7, characterized in that: The blades of the wind wheel adopt H-shaped blades or Ф-shaped blades; The ratio of the total area of ​​the blades to the area of ​​the wind passing through the rotor is called the solidity ratio, which is a reference data for wind turbines. The formula for calculating the blade solidity of a vertical axis wind turbine is: σ=NCL / 2RL=NC / 2R The lift-type vertical axis wind turbine rotor, C is the blade chord length, N is the number of blades, R is the rotor radius, L is the blade length, σ is the solidity ratio; the blade section adopts a main beam skin structure, its surface material is aluminum alloy, the main beam is made of hard aluminum material, forming an O-shaped structure, and the hollow part of the blade is filled with polyurethane.

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