WO2017096645A1

WO2017096645A1 - Adjustable pitch changing device having front end support based on inclined hinge blades

Info

Publication number: WO2017096645A1
Application number: PCT/CN2015/098216
Authority: WO
Inventors: 曾攀; 谢炜; 雷丽萍; 陆红亚
Original assignee: 清华大学
Priority date: 2015-12-10
Filing date: 2015-12-22
Publication date: 2017-06-15
Also published as: CN105508138A; CN105508138B

Abstract

An adjustable pitch changing device having a front end support based on inclined hinge blades, comprising blades, a hub, a fan main shaft, a front end support connecting assembly, and a front-end variable pitch adjusting assembly; each blade of the wind power generator device is an inclined hinge blade; the root portion of the blade is connected to the hub by means of an inclined hinge assembly; the middle front portion close to the root portion of the blade is connected to the front-end variable pitch adjusting assembly by means of the front end support connecting assembly; the front-end variable pitch adjusting assembly mainly consists of a base flange, a main support shaft, a lead screw and a variable pitch motor; the variable pitch motor drives the lead screw, and the front end support connecting assembly enables the inclined hinge blade to generate out-plane tilting, so that a corresponding windward attack angle of the blade can be significantly changed to achieve a pitch changing effect. By means of hinge support, the connection of the root portion of the blade bears no bending moment, and the stress state of the fan device is greatly improved. The device provided by the invention has a simple structure, balanced stress, control convenience and the like, and is suitable for variable pitch adjustment of large/medium fans.

Description

Front end support adjustable pitch device based on inclined hinge blade

Technical field

The invention relates to a large and medium-sized wind turbine blade structure and belongs to the field of wind power generation equipment.

Background technique

Wind energy resources are abundant in the world, and almost all regions and countries have considerable wind energy reserves. In recent years, oil crises have occurred frequently. The oil reserves and coal reserves of all countries in the world will be exhausted within hundreds of years. Therefore, China, the United States, the United Kingdom, Spain and other countries have gradually shifted their attention to the development and utilization of new energy. As one of the important components of renewable energy, wind energy has attracted the attention of researchers and has received strong support from governments.

From the 1970s to the modern era, the world's wind power has made amazing development. In 1996, the world's total wind power generation was only 12.2 TWh; ten years later, in 2008, the world's wind power generation reached about 219 TWh, accounting for 1.1% of the world's total power generation of 20,261 TWh. In three years, the world's wind power The power generation reached 460 TWh (2011), accounting for 2.1% of the world's total power generation of 22018 TWh.

In the early 1990s, a 200kW fan designed and manufactured in Germany was put into operation on a large scale. The wind turbine has a diameter of 25m and a tower height of 30m. In March 2011, Vestas released a 7MW offshore wind turbine with a diameter of 164m. Mitsubishi Power Systems Europe (MPSE) has released a 7MW offshore wind turbine with a diameter of 165m. Siemens, Alstom and Nordex also launched a large 6MW wind turbine in 2011. The large size of the blades can significantly enhance the wind turbine. The installed capacity of the single unit significantly improves the utilization efficiency of wind energy in the wind field.

The fan blades are constantly moving toward the large-scale direction. The weight and rated power of a single blade are proportional to the cubic and quadratic relationship of the blade length. Currently, the mainstream wind power generation equipment for land and sea is 1 to 3MW and 3 respectively. ~5MW, the blade length is 26 ~ 50m and 50 ~ 65m. As the length of the blade increases, the weight increases too fast, and the problems of transportation and installation, etc., make lightweighting the focus of research. In the past, wind turbine blade materials used mainly wood, canvas and metal. Nowadays, new composite materials such as light-weight FRP and carbon fiber reinforced composites are mainly used. Danish LM has always been the world's largest wind power group with a market share of 45%. The longest blade currently produced by LM is 61.5m, made of epoxy-based glass fiber reinforced composite material, and the weight of a single blade reaches 17.7 tons. It can be seen that simply relying on composite materials such as FRP can not meet the development requirements of large-scale and lightweight blades. New research must be done from the blade, blade system, etc.

At present, the development trend of wind power equipment is: large-scale, lightweight, offshore wind power, high reliability, high controllability, and reasonable manufacturing/installation/maintenance costs. The pitching technology of large wind turbines is a core technology of power regulation. At present, the pitching principle is realized by the rotary bearings at the root of the blade. This pitching method is called the blade self-rotating pitching mode. The existing large-sized wind turbine blades adopt a cantilever beam structure, and a pitch bearing is installed at the root. The bearing has to bear the stress of six components caused by the self-weight and aerodynamic load of the large blade, wherein the root of the cantilever beam is at the root of the cantilever beam. The resulting bending moment will be very large, which poses a great challenge to the pitch bearing. Generally, large-diameter, heavy-duty bearings are used, and the manufacturing, installation and maintenance costs are very high, and the reliability is also difficult to guarantee. How to solve the contradiction between blade pitch and blade root force is a challenging problem.

"Single-rotor horizontal-vertical-axis combined wind turbine system" (license announcement number CN100338359C) gives a way to passively adjust the power of the blade under the action of wind-load thrust, which is a downwind arrangement, the blade Only when the wind is large, the sweeping area of the blade changes due to the movement of the spring rod under the action of a large thrust, and thus the wind energy can be absorbed, but the blade has almost no angle of attack change. The effect of pitching is very limited, and active control under any conditions cannot be achieved, for example, stopping under any conditions; and the spring rod movement is a passive motion with large uncertainty while the blades are dumping There is also a large rotational centrifugal force that makes this uncertainty more complicated.

The Chinese patent document (Application No. 201210526207.3) proposes a two-stage inclined folding blade device for a large-scale wind power generator, which comprises a fan hub, a two-stage combined blade and a blade connecting device, and the main blade of the two-stage combined blade is fixed The blade, the folded blade is a rotating blade. The technology has two characteristics: one is the use of inclined folding blades, so its pitching mode is the hinge rotation of the blade, because the blade hinge rotation axis is at an angle with the reference axis on the main blade, which is oblique folding Rotating, the blade will change the angle of attack with respect to the incoming flow when the blade is tilted and folded, so that the pitching effect will be produced; the second is the segmented blade structure, the main blade is the fixed blade, and the front blade is the folding pitch. The blade, the folding pitch drive will be placed at the segmented blade. If it is a three-blade fan, three sets of drive devices are required. After the front blade is folded, the folding pitch drive is driven by the large rotational inertia force. The force state of the device becomes very complicated. Therefore, this requires sufficient space in the middle of the blade to properly position the tilting folding blade device to provide the driving power for the blade folding, and also has sufficient strength to ensure safety under stress conditions, which gives the device The application presents a big challenge. In response to this problem, the patent of the present invention is based on the pitching principle of the inclined hinged blade, and proposes a pitching mode of the full blade. The linear motion of the supporting tie rod drives the tilting of the inclined hinged blade to change the relative angle of attack of the blade against the wind. It plays the role of pitching; since the blade is hinged support, the blade root does not bear the bending moment, which greatly improves the force state of the fan device. Only a set of pitch drive device for linear movement of the screw is needed, so that all the driving devices can be placed on the hub, and the folding and pitching of the whole blade can be realized, and the blade power can be easily adjusted in the wind power technology, and the blade can be easily adjusted. The two goals of improving the state of stress.

Summary of the invention

The invention aims at two core technologies of simple power adjustment of the fan and improvement of the blade force state, and proposes an adjustable pitch device based on the front end support of the inclined hinge blade.

The technical solution of the present invention is as follows:

A front end support adjustable pitch device based on inclined hinged blades, comprising a blade, a hub, a fan main shaft, a tilting hinge assembly, a front end support connection assembly and a front end pitch adjustment assembly, wherein the blade of the wind power generator device is The inclined hinge blade; the root of the blade is connected to the hub through the inclined hinge assembly, and is connected to the front pitch adjustment assembly in the blade root region through the front end support connection assembly; the front pitch adjustment assembly includes: a base flange, a front support shaft, a pitch motor, a screw sleeve sleeve and a hollow screw; the front support shaft is connected to the cylinder of the base flange through a front support shaft connecting bolt; the base of the base flange is fixed to the hub by a base connecting bolt; The lead screw is fixed on the front support shaft through the front support bearing of the lead screw and the rear support bearing of the lead screw; the front end of the hollow lead screw is provided with a screw sleeve outer sleeve slider for rotating motion, and a screw drive gear is fixed at the rear end thereof. The outer sleeve of the screw sleeve is in sliding contact with the slider rail; the slider rail is fixed on the rail bracket; the root of the rail bracket It is fixed to the hub; pitch motor gear engaged with the spindle drive motor via a transmission gear, the pitch is fixed to the motor hub via a bracket.

The technical feature of the present invention is further that the inclined hinge assembly comprises a hub hinge bracket and a blade hinge bracket, the blade hinge bracket is fixed at the root of the blade, the hub hinge bracket is fixed on the hub, and the blade hinge bracket and the hub hinge bracket have a plurality of corresponding Hinged holes, each hinged hole is connected by hinged bearings and bolts.

The technical feature of the present invention is also that the front end support connecting assembly comprises a support pull rod, a blade connecting support, and a slider connecting support; the blade connecting support is fixedly connected with the blade, the self-rotating universal joint is installed, and the self-rotating universal joint is adopted The joint is connected with the support rod, the slider connecting bracket is fixedly connected with the outer sleeve sleeve of the screw rod, and the hinge bearing is installed, and is connected with the support rod through the hinge bearing.

The technical feature of the present invention is also that the hinge axis of the blade hinge bracket in the tilt hinge assembly is inclined at an angle of 45 to 75 between the hinge axis formed by the blade string.

Compared with the prior art, the invention has the following characteristics and outstanding effects: 1 using a complete inclined hinged blade, the angle of attack of the blade is changed by the tilting of the blade, and the blade has obvious effect, and the pitch adjustment component is mainly Bearing screw, the adjustment method is linear motion, very simple, the hinge connection between the 3 blades and the hub, the force transmission mode is the support tie rod, so that the root of the blade does not bear the moment load, the force state is greatly improved, 4 due to The pitching mode is relatively simple and the stress state is improved, which greatly improves the reliability of the fan system and facilitates installation and maintenance. Therefore, the front end support adjustable pitching device based on the inclined hinge blade has the characteristics of simple structure, balanced force and simple control.

DRAWINGS

1 is a front view of a front end support adjustable pitching device based on a tilt hinged blade provided by the present invention.

2 is a side view of a front end support adjustable pitching device based on a tilted hinged blade.

Figure 3 is a detailed schematic view of the front end support adjustable pitch device.

In the figure: 1-inclined hinged blade; 2-hub; 3-front support connection assembly; 4-front pitch adjustment assembly; 5--inclined hinge assembly; 5a-blade hinge bracket; 5b-hub hinge bracket; 5c-hinging axis 5d-blade string; 6-elastic axis tilt angle; 7-impeller rotation direction; 8-spindle; 9-spindle support bearing; 10-support tie rod; 11-blade connection support; 11a-rotary universal joint; 12-slider connection support; 13-screw outer sleeve slide; 13a-slider guide; 13b-rail support; 14-hollow screw; 15-screw drive gear; 16-motor drive gear; Pitch motor; 18-bracket; 19-base flange; 20-front support shaft; 21-screw front support bearing; 22-screw rear support bearing; 23-base connecting bolt; 24- front support shaft connecting bolt; 25-wind direction; 26-sleeve direction of movement; 27- fairing.

detailed description

The structure and specific embodiments of the present invention are further described below with reference to the accompanying drawings:

1 is a front view of a front end support adjustable pitching device based on a tilt hinged blade provided by the present invention, the device comprising a blade 1, a hub 2, a fan spindle 8, a tilting hinge assembly 5, a front end support connecting component 3 and a front end a pitch adjustment assembly 4, the blades of which are inclined hinged blades 1, the roots of which are connected to the hub 2 by a tilting hinge assembly 5, and connected to the front pitch adjustment assembly 4 in the blade root region by a front end support connection assembly 3 The hinge axis 5c of the blade hinge bracket 5a in the tilt hinge assembly 5 and the hinge axis 5d form an angle of inclination 6 between 45° and 75°.

Figure 2 is a side view of the adjustable pitch control device based on the front end of the inclined hinged blade, and Figure 3 is the front end support adjustable pitch paddle. Schematic diagram of the details. The front end pitch adjustment assembly 4 includes: a base flange 19, a front end support shaft 20, a pitch motor 17, a screw outer sleeve slider 13 and a hollow screw rod 14; the front end support shaft 20 is connected to the shaft through the front end support shaft 24 is connected to the cylinder of the base flange 19; the base of the base flange 19 is fixed to the hub 2 by the base connecting bolt 23; the hollow screw 14 is fixed at the front end by the lead screw front support bearing 21 and the screw rear support bearing 22 The front end of the hollow screw 14 is provided with a screw outer sleeve slider 13 for performing a rotary motion, and a screw drive gear 15 is fixed at the rear end thereof; the outer sleeve slider 13 and the slider guide 13a is in sliding contact; the slider guide 13a is fixed on the rail bracket 13b; the root of the rail bracket 13b is fixed on the hub 2; the pitch motor 17 is engaged with the screw drive gear 15 through the motor transmission gear 16, and the pitch motor 17 is passed through the bracket 18 is fixed to the hub 2.

The tilt hinge assembly 5 includes a hub hinge bracket 5b and a blade hinge bracket 5a. The blade hinge bracket 5a is fixed to the root of the blade, and the hub hinge bracket 5b is fixed to the hub. The blade hinge bracket 5a and the hub hinge bracket 5b are provided with corresponding ones. Hinged holes, each hinged hole is connected by hinged bearings and bolts.

The front end support connection assembly 3 includes a support rod 10, a blade connection support 11 and a slider connection support 12; the blade connection support 11 is fixedly coupled to the blade, is mounted with a self-rotating universal joint 11a, and passes through the self-rotating universal joint 11a Connected to the support rod 10, the slider connection support 12 is fixedly connected with the outer sleeve sleeve 13 of the screw, and the hinge bearing is mounted, and is connected to the support rod 10 through the hinge bearing.

The fan impeller rotates along the direction of rotation of the impeller. When the wind speed is too large and the speed of the impeller is too fast, it is necessary to adjust the angle of attack of each blade in the impeller with respect to the incoming flow, and start the pitch motor 17 to drive the motor transmission gear 16, and Driving the screw drive gear 15 causes the hollow screw 14 to rotate, thereby driving the outer sleeve slider 13 of the lead screw to linearly move toward the front end, and pulling the blade 1 forward by the support rod 10, since the root of the blade passes through the inclined hinge assembly 5 and The hub 2 is connected, and there is an inclination angle α of the hinge shaft. When it tilts forward, the blade must be tilted out of the way, thereby changing the relative angle of attack of the blade against the wind, and functioning as a pitch; therefore, through the hollow wire The forward or reverse rotation of the bar 14 can linearly move the outer sleeve slider 13 toward the front end or the rear end, thereby causing the blade to tilt forward or backward to adjust the angle of attack of the blade relative to the incoming flow. It becomes larger or smaller; while the blade is tilted, it also makes a large change in the sweeping area of the blade, which can also enhance the effect of pitching. Since the blade is an articulated support, the blade root does not bear the bending moment, and the force state of the fan device can also be improved. In the pitching drive process, only a pitch drive device with a linear motion of the screw is needed on the hub, so that the folding pitch of the whole blade can be realized, and the blade power can be easily adjusted and the blade force can be well realized in the wind power technology. The state of improvement is the two major goals.

Claims

A front end support adjustable pitch device based on inclined hinged blades, comprising a blade, a hub, a fan main shaft, a tilting hinge assembly, a front end support connection assembly and a front end pitch adjustment assembly, wherein the blade is a tilt hinged blade ( 1); the root of the inclined hinged blade is connected to the hub (2) through the inclined hinge assembly (5), and is connected to the front pitch adjustment assembly (4) through the front end support connection assembly (3) in the blade root region;

The front pitch adjustment assembly (4) includes a base flange (19), a front support shaft (20), a pitch motor (17), a screw outer sleeve slider (13), and a hollow screw (14) The front support shaft (20) is connected to the cylinder of the base flange (19) through the front support shaft connecting bolt (24); the base of the base flange (19) is fixed to the hub by the base connecting bolt (23) (2) The hollow screw (14) is fixed on the front support shaft (20) through the screw front support bearing (21) and the screw rear support bearing (22); the front end of the hollow screw (14) is provided with a rotary motion. a screw sleeve outer sleeve slider (13), the rear end of which is fixed with a screw drive gear (15); the outer screw sleeve slider (13) is in sliding contact with the slider guide rail (13a); the slider guide rail ( 13a) fixed on the rail bracket (13b); the root of the rail bracket (13b) is fixed on the hub (2); the pitch motor (17) is engaged with the screw drive gear (15) through the motor transmission gear (16) The paddle motor (17) is fixed to the hub (2) by a bracket (18).
A tilting hinged blade-based front end support adjustable pitching device according to claim 1, wherein the tilting hinge assembly (5) comprises a hub hinge bracket (5b) and a blade hinge bracket (5a), the blade hinge bracket (5a) fixed at the root of the blade, the hub hinge bracket (5b) is fixed on the hub, and the blade hinge bracket (5a) and the hub hinge bracket (5b) are provided with a plurality of corresponding hinge holes, and each hinge hole is hinged Bearings and bolts are connected.
A tilting hinged blade-based front end support adjustable pitching device according to claim 1 or 2, characterized in that the front end support connection assembly (3) comprises a support tie rod (10), a blade connection support (11) and a slider connecting support (12); the blade connecting support (11) is fixedly connected with the blade, is mounted with a self-rotating universal joint (11a), and is connected to the supporting pull rod (10) through a self-rotating universal joint (11a); The slider connecting bracket (12) is fixedly connected with the screw outer sleeve slider (13), and the hinge bearing is installed, and is connected with the supporting rod (10) through the hinge bearing.
A tilting hinged blade-based front end support adjustable pitching device according to claim 2, characterized in that: the hinge axis (5c) of the blade hinge bracket (5a) and the blade string in the tilt hinge assembly (5) 5d) The hinge axis formed by the angle of inclination (6) is between 45° and 75°.