WO2003040554A1

WO2003040554A1 - Vertical axis wind turbine (vawt)

Info

Publication number: WO2003040554A1
Application number: PCT/KZ2002/000011
Authority: WO
Inventors: Albert Vasilievich Bolotov; Sergei Albertovich Bolotov
Original assignee: Albert Vasilievich Bolotov; Sergei Albertovich Bolotov
Priority date: 2001-11-08
Filing date: 2002-07-09
Publication date: 2003-05-15
Also published as: EA003784B1; EA200200694A1

Abstract

The invention relates to power engineering and the use of wind power for the generation of power being supplied for power systems or the use for feeding individual consumers. The technical result of the invention is the simplification of the structure and operation of wind energetic units (WEU) and wind-power stations (WPS) at the account of unification of WEU blocks and increase of utilization factor of wind power. It is achieved by the fact that in WEU, including one or several cylindrical blocks with stators and rotors, the outside diameter of rotors of blocks is constant for all blocks, that provides their unification. The block stators can be supplied with blowers, made in form of additional plates attached to the stator plates. The vertical shaft, to which the rotors of all blocks are connected, is connected to the rotor of the multi-pole multi-operation electric generator supplied with systems of automatic control of output capacity, accumulation of information about wind activity and its use for adjustment. Multi-unit high-power WPS are packed from WEU, located in lines or groups so that to except their shading by the ahead standing WEU with regard for the prevailing wind rose.

Description

VERTICAL AXIS WIND TURBINE (VAWT)

The invention relates to power engineering and the use of wind power for the generation of power being supplied for power systems or the use for feeding individual consumers. There has been known a number of types of wind-energetic units (WEU) and wind-power stations (WPS), including WEU with horizontal and vertical axes of rotors, propeller-, drum- and rotor-type [Robert Gasch (Hrsg). Windkraftanlagen - B.G. Teubner Stuttgart, 1993]. However, only propeller two- and three-blade units have become practically used. They have a complicated design of the blades, expensive reducer with a large reduction ratio, generator, computer for blade position control and facing the wheel into the wind. Because of large mass of the wind-wheel and blades, the systems of their position control can not provide coiτect facing of the wheel into the wind fast changing its velocity and direction. As a result of constant nonconformity of setting the blades and wheel position with the direction and velocity of the wind according to height, utilization factor of WPS installed capacity does not exceed 10-23 %. Thereby wind-power engineering based on the use of propeller WEGP can not exist now without the government support and grants. For getting a chance of using a wind of any direction, the WEU designs with vertical arrangement of blades are known, Darier type [Robert Gasch (Hrsg). Windkraftanlagen - B.G. Teubner Stuttgart, 1993; Siegfried Heier. Windkraftanlagen im Netzbetrieb, B.G. Teubner Stuttgart, 1996], Savonius rotor [US Patent No. 413407, cl.415-H, 1979], but non of them got distribution because of their complexity.

There has been known a wind-rotor power station [Patent of the Republic of Kazakhstan No. 3355 cl. F03,fl, 3/4. Wind-rotor power

5 station BONI -V Bull. No. 2,1996], whose units comprise modules consisting of cylindrical rotors with volumetric profile blades and mobile directing devices, the position of which as respects the wind direction is set by a vane. For power generation two or several generators connected to the shaft of the rotor through breakdown couplings and mechanical _{j Q} gears are used.

However, when using this device, practically there is no possibility of operative control over the position of the directing device at multi-modular stations because of its large mass, the working space of the rotor is loaded by volumetric blades, that excludes a chance of

₁5 getting a high wind power utilization factor. The availability a breakdown coupling and mechanical gears complicates the design and makes it more expensive.

Closest to the invention is a wind-rotor power station [Patent of the Republic of Kazakhstan No. 5595 cl. F03 R 3/4.Bull. No. 9, 1999], 0 whose units consist of wind-rotor blocks or modules including cylindrical directing devices and blade vertical wind-rotors, designed with the use of Helman formula, connected with the generating group. However, this offer has also some drawbacks. The diameters of directing devices and module rotors, and also the amount of blades in module rotors is changed according to the height of the unit in accordance with Helman formula, which does not give reliable results in real conditions and does not cover all the multiplicity of operating conditions of wind- power stations in the bottom layer of the air flow, and the difference of sizes and designs of rotors in one unit complicates manufacturing and increases the WPS cost. Besides, in a wind-rotor WPS it is provided a multi-serial installation of wind units in compact parallel lines, that hinders the possibility of an effective utilization of the wind flow power at a multi-vector wind rose, when the neighboring units shade one another, and the distance between the lines is supposed to be not less than 10-multiple WEU height, that requires a considerable territory for WPS installation and increases the length of internal connective current networks. Placing of the hoisting crane on the top of WEU predetermines the necessity of considerable strengthening of the construction and making it more expensive.

The object of the invention is the creation of wind-electric units of a block type, and also multi-unit stations providing the increase of utilization factor of wind power and specific generation of electric energy per 1 kilowatt of installed capacity of the electric generator.

The technical result from the use of the invention is the simplification of the structure and operation of WEU and WPS at the account of unification of WEU blocks and increase of utilization factor of wind power at a multi-vector wind rose (WR). It is achieved by the fact that in the wind energetic unit (WEU), including one or several cylindrical blocks installed in succession and concentrically in a vertical line, each of which comprises a stator with concave-convex plates and rotor with concave-convex blades, connected with vertical shaft common for all blocks, the bottom end of which is connected to the generator rotor, in all blocks the rotors have a constant outside diameter, the ratio between outside diameters of stator and rotor is within the range of 1.2 ÷ 4.0, the number of blocks in the unit comes to 1 ÷ 50 depending on the height of one block and wind conditions, and between the blocks in WEU there are some gaps supplied with ring conic shields. And at the same time the rotors of all blocks contain equal number of blades "K_r" determined according to the formula:

D ₊ D

K" = π r 2

D _ D

Where D_r - rotor outside diameter, D₂ - rotor diameter along the internal ends of the blades, radial length of rotor blade "/" is equal to the distance between the blades, measured along the circle of the rotor blades middles

D _L D

D ₌ ^{r 2} mb Λ with diameter and is determined under the formula accurate within ±50 %, and the ratio of the outside rotor diameter and the

diameter of the internal ends of plates — - = 1,05 ÷ 3,5 is determined under

A

the formula / = — = — - . Besides number of stator plates "K_s" and

2 K. K number of rotor plates " K_r " are connected by a ratio — '- = 1 ÷ 4 , and the

stator cross sizes are determined by a ratio — — = 1,2 ÷ 4 , where D_bs -

-^ int stator diameter along the outside ends of plates, D_int - stator diameter along the internal ends of plates. It is also achieved by the following: the blocks can be supplied with blowers, made in the form of additional concave-convex plates fixed on the outside ends of the stator plates. Therewith, each stator plate can be attached by a single blower plate having a bend being corresponding to a bend of the stator plate or the stator can comprise, at least, two complex components of connecting with the blower, in which to one of the stator plates there two blower plates, having different radiuses of curvature and/or different directions of convexities are joined, and the planes passing through the blower plates in complex connector assemblies divide the WEU block into sectors taking in a wind load with the formation of the sector aperture angles between the said planes, where the sector aperture angles depend on a real wind rose and for one-vector wind rose they come to 180 ÷ 210°, for two-vector - 150 ÷ 170°, for three-vector - 60 ÷ 140° - individually for each sector of the block. Besides, the rotor of each block has face and intermediate basic disks for connecting blades with the shaft, in which through-windows are made. It is also achieved by the fact that in the WEU there has been installed a multi-pole multi-operation gated direct current generator, voltage - 12 ÷ 1000 V with the system of automatic actuation control, for ensuring direct voltage when the wind power changes and when it is possible to use the energy of short-term gusts, storms and hurricanes, and with the system of analysis of electrical circuits state supplied with outlet protective relay. Besides, the generator is supplied with a mechanical rotor brake including a brake disk, installed above the top cover of the generator, fixed on the rotor and at the same time having functions of a canopy for the generator, where the brake is supplied with a trigger actuated from the electric drive or manually. Besides, WEA has a control unit to operate the generator regimes including regulator of the generator output power for ensuring nominal frequency of the rotor within the range of n_nom = (0.3 ÷ 0.7) n_xx, where n_xx - frequency of rotor rotation in idle running at the wind velocity in real conditions, and in the top part of WEA blocks, vanes are installed with the electromagnetic gauge of wind velocity vector, and electrical anemometers for ensuring, together with the control unit of the generator operation regimes, long-term registration of wind activity and of the electric power generated.

It is also achieved by the fact that WEA is supplied with the analyzer of the generator loading for ensuring regulation of the number of the connected consumers or switching on a ballast load at the insufficient number of consumers and has a tachometer generator connected with the generator rotor and relay of switching on- and off of the generator actuation, being fed from the tachometer generator, or from a residual voltage of the generator, for switching on the generator actuation under the wind power- containing velocities.

WEA can be installed on piles, platform, or in a reservoir on a raft.

It is also achieved by the fact that the wind-power station (WPS) includes several WEU under the present invention, where the wind units included in WEU are connected with the adjacent WEU by rigid bundles for raising their stability, WEU are installed on supporting trestles, over which there are their wind-mechanical parts from the blocks with stators and rotors, and under the supporting trestles a machine hall is placed. WEU, being included in WPS can be placed in one or two lines with the distance between the units in a line at a distance (0.6÷10) D_{s o} , where - D_{s 0} is the stator outside diameter along the plates of the blower, depending on the fluctuation of the direction and velocity of the wind, and the distance between the lines (0.8÷10) D_{s α}, where the units of the second line are located in points corresponding to the middles of the distance between the units of the first line, or can be located in groups along the closed contour in the amount of 3 or 5 or 7 groups being set at distances, making for reset of the speed of the wind flow, passing through the groups located ahead, the number of units being 3, 5 or 7 in a group of being located according to the circuit, excepting the shading of one unit by another. The unification of rotors and the parameters of stators, being appropriate to them, allows to simplify the structure and repair of WEU and WPS. Making gaps in the bullheads of rotors and gaps between the blocks facilitate the air flow through the block and provide the increase of operating ratio of a wind power. The setting of blowers, whereby control of conditions of forcing a wind flow by choosing their sizes and formation by them of optimal angles of opening the block sectors can be provided, also allows to increase operating ratio of a wind power at any heights of placing the blocks in WEU and at any wind rose. The use of the gated multi-pole multi-operation direct current generator with the system of automatic actuation control allows to provide voltage stability under sudden change of wind conditions, and the control equipment of the generator operation mode provides an optimum mode depending on the external factors. The use of offered WEU allows creating multi-unit WPS, also possessing the said advantages. And the offered placing of WEU in multi-unit WPS, where minimum shading of units is achieved by ensuring their compact displacement, improves the use of energy of air currents and reduces losses of energy to the own needs of the station.

The essence of the invention is explained by drawings, where in figure 1 the general view of the unit is shown by disposing the units in two lines. In figure 2 the sections of blocks are shown according to A-A and B-B in figure 1 , figure 3 gives the schemes of setting the blowers under 2- vector (a) and three-vector (b) wind rose. Figure 4 shows the cross section of a rotor, figure 5 shows the longitudinal section of the block, figure 6 gives the schemes of the units arrangement in WPS under different wind roses: - a, b - single-line and double-line in a two-vector wind rose, c - group disposition of double-line WPS, d - group disposition of units in multi-vector wind roses.

The wind energetic unit consists of blocks 1 , comprising a stator 2 with concave-convex plates 3 and rotor 4, comprising convex-concave blades 5, located along the circle. The installed against each other blocks form a column with a common shaft, the bottom end of which is connected to electrical generator 6. The outside diameter of rotor D_r is installed constant for all blocks with the aim of their unification. It is selected out of the conditions for getting the needed capacity in wind conditions, the data of which are obtained by preliminary studies in the locality or from the information of Hydrometeoservice. Proceeding from the same conditions the diameter of rotor is determined according to the internal ends of blades (D₂) with regard for the ratio D_r/D₂=1.05÷3.5, the base outside diameter of stator, i.e. its diameter along the outside ends of blades (D_sb) with regard for the ratio D_sb D_r = 1.2÷4.0, the number of blocks Z in the unit, at Z=T÷50, the number of rotor blades, determined

D ₊ D

V r _

K. - _π

D _ D according to the formula: ^{r 2} , and the radial length of the blade "/", equal to the distance between the blades, measured along

the middle circle of the rotor, having a diameter D - — , where the length "/" is determined according to the formula / = — - = — - with

² R, an accuracy of ± 50 %.

Wind conditions in the locality also dictate the need for setting, on a number of WEU blocks, some blowers in the form of additional directing plates 7, attached to plates 3 of the stator. In conditions of a multi-vector wind rose each plate of the blower is attached to each plate of the stator, and at one-, two- or three-vector wind roses the circle of the stator by means of the plates of the blower is divided into sectors. For this purpose plates of the bowler in two with different radiuses of curvature, and/or different directions of convexities are attached to the stator plates located in the borders of the sectors. Conventional planes, traced through these plates, will delimit the sectors, and the angles between them are the angles of opening the sectors. At one-vector wind rose these angles come to 150-170°, at two-vector - 150-170°, at three- vector - 60-140°. Sectors with the largest aperture angles are set according to vectors of the wind rose . It allows to load each block to the limit and equally and to provide maximum operating ratio of the installed capacity of the electric generator under the conditions of one-, two-, three- and multi-vector wind roses. For simplification of the outgoing air passing from the rotors, between the blocks of the column there are gaps 8, covered with shields 1 1 , and the bullheads of blade fastening 5 of the rotor 4 are made with through apertures formed by spokes or windows. On the shaft, connected to the rotor of the electric generator 6, the compactor 12 is installed, protecting the generator from the ingress of moisture. The duplication of moisture protection of the generator is provided with rotating disk 13, being at the same time a canopy and brake disk 14, switched on- and off automatically or manually by means of drive 15. The brake is brought into operation by the outlet protective relay of generating circuits and can be used at repair work.

For ensuring the generation of electrical energy corresponding to the air flow power a multi-pole multi-operation direct current generator 6 is installed with output voltage 12÷1000 V depending on its capacity, supplied with system 16 of automatic switching on actuation within the range of the wind power-bearing velocities, providing constancy of voltage under changing wind velocity over a wide range and parallel work with the same generators with overloading ability 1.5 - 4.5. The output of WEU to power systems, and as parallel work with generators of other types is being carried out through the inverter.

The optimization of work of the electric generator according to electrical load and the current value of wind velocity with observance of the ratio n_nom = (0.3÷0.7) n_xx is provided with a system of automatic control 16, including electrical anemometers with electromagnetic vanes 17, being installed in the upper part of blocks 1 and on the top of WEU under lightning conductor 23, and also electronic block 18 accumulating the continuous information about wind, needed also for the calculation of radial length and angles of setting blowers 7. Here n_nom - nominal frequency of rotation of a rotor at an optimum load, n_xx - frequency of rotation of a rotor in idle running of the generator (without actuation).

The generator has an analyzer of loading (not shown) regulating the porting of groups of consumers of different importance, or switching

5 on ballast when there is no need or it is impossible to connect consumers. When the wind velocity is decreased, the analyzer prohibits connection of insignificant consumers.

The generator is also supplied with the relay of switching on- and off exciting current being powered from the tachometer generator,

, connected with the rotor or from the transformed residual voltage of the generator intended for energizing excitation at the wind power-bearing velocities.

It is possible to install WEU under the conditions of weak soils on piles or platforms, and also - in pools, using rafts.

15 If it is necessary to generate electric energy in large volumes wind-driven units are combined to multi-unit wind-power stations (WPS) and are installed according to a certain linked arrangement dependent on a local wind rose (Figure. 6). So, at one-vector and two- vector WR the units are arranged perpendicularly to the basic vector WV 0 in one or two number lines (Figure 6 a, b) with a distance between the units in a line chosen within the limits of A = (0.6 - 10) D_so, where D_so - outside diameter of the stator with blowers, and the distance between the lines (Figure 6 b) is determined according to the ratio B = (0.8- 10) D_so. The distance between the multi-unit stations (Figure 6 c) is determined by the actually measured recovering of the air flow velocity in the locality. The units in the line are connected among themselves in the top part by longitudinal stitches 19, and cables 20 with bases. At a two-line arrangement the units are additionally strengthened by connections between the neighboring lines 21.

At three-vector and multi-vector wind roses the units are arranged by "bushes" in the amount of 3-5-7 units in a bush (Figure 6 d), strengthened by stitches at different levels of columns and are provided with common protection against impacts of lightning in the form of a pin-type lightning-conductor 22.

With the aim of carrying out the assembly, disassembly and service, the generators 6 are installed in the machine room 23 on adjustment platforms 24, allowing to install the generator exactly towards the wind mechanical column, installed on the roof of the unit basis or on the platform of the multi-unit wind-power station 25.

The operation of WEU and WPS is being carried out as follows. In each block 1 of WEU stator 2 captures the airflow by the ends of plates and, directing it to the rotor blades, provides its compression and acceleration. Using the blowers 7 this process gains in strength. As a result, the wind power being transferred by the rotor blades is 1.2-4 times higher than the energy of a free airflow. After passing through the rotor blades the airflow passes through apertures in basic disks 10 and through gaps 8 between the blocks comes out. Thus, it experiences minimum possible resistance that increases operating ratio of a wind power.

Effecting the rotor blades 5, the airflow causes rotation of the rotor connected by basic disks 9 with common for all blocks by the central shaft. And the shaft transmits rotation to a rotor of the electric generator 6, generating electric power.

When constructing wind-power stations, combining several WEU, the wind flow coming to WEU is captured and is braked by separate WEU and if other WEU are blocked by those located ahead, they will use a weakened wind flow. But if they have two WEU ahead of them, narrowing the pass for a wind flow and, hence, raising its velocity, the operation efficiency of such WEU considerably grows. With regard for this circumstance the circuits of the WEU arrangement in WPS are accepted.

Claims

1. Wind energetic unit (WEU), including one or several cylindrical blocks installed in succession and concentrically on a vertical line, each of which comprises a stator with concave-convex plates and rotor with concave-convex blades, connected with the common for all blocks vertical shaft, the bottom end of which is connected to a rotor of the generator wherein in all blocks the rotors have a constant outside diameter, the ratio of outside diameters os stator and rotor is within the limits of 1.2 ÷ 4.0, the number of blocks in the unit is 1÷50 depending on the height of one block and wind conditions, and between the blocks in WEU there are gaps supplied with ring conic shields.

2. WEU as set forth in claim 1 wherein the rotors of all blocks comprise identical number of blades "K_r, determined by the formula:

D + D r r 2 ^κ = π D D

where D_r - outside diameter of a rotor, D₂ - diameter of a rotor along the internal ends of the blades, radial length of the rotor blade " ^l" is equal to distance between the blades, measured along the circle of middles of the

rotor blades with a diameter D = — and is determined by the

2 ^J

formula / = — ^- = — - with an accuracy of ±50 %, and the ratio of

2 K „ the outside diameter of the rotor and diameter of the internal ends of

plates is — - = 1,05 ÷ 3,5

3. WEU as set forth in claim 2 wherein number of the stator plates "K_s" and the number of the rotor "K_R" are connected by a ratio

c — - = 1 ÷ 4 , and the cross sizes of the stator are determined by a ratio

^h- = 1,2 ÷ 4 , where D_bs - diameter of the stator along the outside ends of

plates, Di_nt - diameter of the stator along the internal ends of plates.

4. WEU as set forth in claim 3 wherein the blocks are supplied with blowers, made in the form of additional concave-convex plates 0 fixed on the outside ends of the stator plates.

5. WEU as set forth in claim 4 wherein each stator plate is attached by one plate of the blower, having a bend corresponding to the bend of the stator plate.

6. WEU as set forth in claim 5 wherein the stator comprises, at least, two complex units of connection with the blower, in which two plates of the blower are connected to one plate of the stator, having different radiuses of curvature and/or different directions of convexities, and the planes conducted through the plates of the blower in complex conjunctive units divide the block WEU to sectors taking in the wind 0 load, with the formation between the mentioned planes of the sector aperture angles, where the sector aperture angles depend on a real wind rose and constitute for an one-vector wind rose the come to 180÷210°, for two-vector - 150÷170°, for three-vector - 60÷140° individually for each sector of the block.

7. WEU as set forth in claims 2 and 4 wherein the rotor of each block has face and intermediate basic disks for connecting the blades with the shaft, in which through windows are made.

8. WEU as set forth in claims 1-7 wherein on it there is a multi- pole multi-operation gated direct current generator with voltage of 12÷1000 V with the system of automatic control of excitation, for ensuring a constant voltage at change of wind power and possibility of using energy of short gusts, storms and hurricanes, and with system of analysis of state of electrical circuits protection, supplied with the protective relay.

9. WEU as set forth in claim 8 wherein the generator is supplied with a mechanical brake of a rotor containing a brake disk, installed above the top cover of the generator fixed on the rotor and at the same time executing functions of a canopy for the generator, where the brake is supplied with a trigger actuated from the electric drive or manually.

10. WEU as set forth in claims 2 and 4 wherein it has control unit of the mode of operation of the generator including regulator of output capacity of the generator for ensuring nominal frequency of rotation of a rotor within the range of n_nom = (03÷0.7) n_xx, where n_xx - frequency of rotation of a rotor in idling running at the velocity of the wind in real conditions.

11. WEU as set forth in claim 8 wherein in the top part of blocks of WEU there have been installed vanes with the electromagnetic gauge of a vector of velocity of the wind and electrical anemometers for ensuring, together with the control unit of the generator operation conditions, long-term registration of wind activity and of the electric power generated.

12. WEU as set forth in claims 8-11 wherein it is supplied with an analyzer of loading the generator for regulating the number of porting consumers, or switching on a ballast load when it is impossible to connect consumers.

13. WEU as set forth in claims 8-12 wherein it has tachometer generator, connected with the rotor of the generator and relay of switching on - switching off the excitation of the generator, powered from the tachometer generator or from the residual voltage of the generator, for switching on the excitation of the generator at power bearing velocities of the wind.

14. WEU as set forth in claims 1-13 wherein it is installed on piles or on a platform.

15. WEU as set forth in claims 1 -13 wherein it is installed on a raft in a reservoir.

16. Wind-power station (WPS), including several WEU wherein WEU as set forth in claims 1 -15 are used.

17. WPS as set forth in claim 16 wherein wind units (WEU) being included in WPS are connected with the neighboring WEU by rigid bundles for raising their stability, WEU are installed on supporting trestles, above which there have been placed their wind-mechanical parts from blocks with stators and rotors, and under the supporting trestles a machine hall is placed.

18. WPS as set forth in claim 17 wherein they are located in one or two lines with a distance between the units in a line at a distance (0.6÷10) D_so., where D_so - outside diameter of the stator along the plates of the blower, depending on fluctuation of the direction and velocity of the wind, and the distance between the lines (0.8÷10) D_{s n} , where the units of the second line are located in points corresponding to the middles of distances between the units of the first line.

19. WPS as set forth in claim 17 wherein WEU are located in groups along the closed contour in the amount of 3 or 5 or 7 groups being set at distances causing recovering the velocity of the wind flow passing through the groups ahead at the number of units 3, 5 or 7 in a group arranged according to the scheme, excepting the shading of one unit by others.