CN1009020B

CN1009020B - Control hub for adjusting pitch of wind turbo-propeller

Info

Publication number: CN1009020B
Application number: CN88101156A
Authority: CN
Inventors: 克林特·科尔曼
Original assignee: DAYA ENERGY SOURCE Co Ltd
Current assignee: DAYA ENERGY SOURCE Co Ltd
Priority date: 1988-02-29
Filing date: 1988-02-29
Publication date: 1990-08-01
Also published as: CN1035547A

Abstract

The present invention relates to a wind turbine system with variable propeller pitch, wherein the angle of propeller pitch is determined by a hydraulic actuator which is connected between cranks on a blade propeller adjusting shaft. A hydraulic circuit concentrically passes through a transmission shaft of a rotor, and passes through a swivel pipe joint to arrive at an air charged accumulator on a deflection load carrier. A propeller adjusting shaft line is forwardly connected with a gear system to carry out one to one inverse rotation, preferably on one side of the shaft line of the rotor corresponding to the hydraulic actuator.

Description

Control hub for adjusting pitch of wind turbo-propeller

The control system of the general relevant wind turbine rotor of the present invention, particularly about the automatic control system of the blade pitch of the wind turbine that drives generator, generator links to each other with power supply network.The angle of blade is that pitch can be controlled, and with the adjusting output torque, and in a wind speed scope of design, obtains the highest output power.This is a kind of passive type system of fully-machinery type, and is desirable especially, because be not subjected to the influence of environmental factor and sensed system or control system fault relatively, so reliability is arranged.

The controlled rotor of most existing pitches belongs to active pitch control.Sensor is made sensing to needs, and electromotion system or hydraulic systems are changed pitch.The potential vulnerability in essence of this system is to work as sensed system, or microprocessing systems or actuating system or mechanism can not be adjusted to big propeller pitch angle when breaking down, and turbine is slowed down or stops.

And opposite, even control system has broken down, the automatic recovery system of passive type still can be fed back into safe pitch automatically, i.e. the high attack angle pitch.

U. S. Patent 4,435,646 disclose a kind of wind turbine pitch control system, it comprises that a housing has the parallel blade of spacing to transfer the oar axis to be limited in the plane with a pair of, intersect with rotor axis near described two accent oar axis mid points on this plane and machine control unit vane angle angle when initiatively determining to turn round.This device has the defective of most existing wind eddies wheel pitch control systems.

Main purpose of the present invention is to utilize a reliable power machinery system, the output torque of control feather wind turbine, and it controls the pitch of blade automatically with the blade moment variations that wind-force load and centrifugal force cause.

In the passive pitch control system of a kind of double runner rotor of the present invention, the parallel accent oar of two blades axle directly connects with a train of gearings.The pitch angle depends on the gas-liquid linear actuators that connects between the crank on two sharfs.Hydraulic pipe line passes rotor transmission shaft with one heart, by a swivel joint, connects an air charged accumulator.

In the ideal structure figure of the contrary wind stabilized deflection wind turbine with deflection hub, parallel blade transfers the oar axis to form a rotor plane, passes the rotor transmission shaft line, and the rotor transmission shaft line transfers mid point and rotor plane between the oar axis to intersect two.Be bearing on the hub shell with the accent oar axle of transferring oar axis coaxle line respectively.The blade axle head is sizable length of overlap joint mutually.In desirable embodiment, train of gearings connects the side of diaxon at rotor axis, is having a linear actuators to connect between the crank on the axle on the opposite side.Best and the train of gearings parallel operation of actuator.Scalable hydraulic pressure leverage and " gas spring " between blade accent oar axle provide and control function manually, and can pass through blade feathering autostop.

Fig. 1 is the side view of the tower double-leaf contrary wind of the present invention turbine, and its pitch control rotor hub is in running order.

Fig. 2 be wind turbine along Fig. 1, the plan view of 2-2 line.

Fig. 3 be rotor hub along Fig. 1, the worm's eye view of 3-3 line.

Fig. 4 is the sectional view of the axle head of hub among Fig. 1 along the 4-4 line.

Fig. 5 is the schematic representation of hydraulic system.

Fig. 6 is the wind turbine that is provided with pitch control hub of the present invention, and its predicted power is with respect to the curve of wind speed.

Fig. 1 shows the installation diagram of the contrary wind stabilized deflection double-leaf wind turbine that uses with the synchronous generator coupled of power utilization network.A tower seat 10 is supported liftoff about 70 feet horizontal revolving stage assembly parts 12.A loader 14 is installed on the turntable assembly parts 12, around the vertical axis of turntable assembly parts 12, does the rotation of deflection direction.Install on the loader 14 and rotate axle housing 16, with the hollow rotatingshaft 17 of high moment of torsion of shell 16 supporting the insides.

The front end of double runner rotor 18 and transmission shaft is connected, the transmission shaft rear end connects a pair of induction generator 22 and 24 by gear-box 20, and generator can be done the optimization running respectively under the height wind friction velocity, thereby rotor can be rotated by two corresponding designing requirements under optimum operation speed.Be installed in the free wheel device (not shown) on the gearbox output shaft, can reduce the number of power system control loop and relay box, thereby increase the entire life of equipment, and reduce maintenance.The connection that unidirectional free wheel device can improve alternator/electrical network with separate.

Rotor 18 has a hub 28 that is generally rectangle, as shown in Figure 4, rotates on transmission axis a.Two identical

wind turbine blades

30 and 32 are installed on the hub 28.In specified 100 kilowatts design, the diameter of rotor blade is about 58 feet.Desirable blade has the zero degree tapering, is provided with elasticity and waves hub.The two speed runnings (48/72 commentaries on classics/per minute) that are designed to of rotor should starting automatically under about 7 miles/speed hourly.The tip speed ratio of design is 7-9.

Fig. 2-4 shows the details of hub 28.Hub 28 has pair of cylinders bearing 34 and 36, and

sharf

38 and 40 is bearing in the inside respectively and can rotates, and

cylindrical bearing

34 and 36 determines blade to transfer the position of oar axis b and c respectively.Circle

eccentric mounting flange

42 and 44 connects the opposite end that blade is transferred

oar axle

38 and 40 respectively.Blade 30 and 32(Fig. 1) flange 46 and 48 that matches is with it arranged, be installed on

flange

42 and 44 with bolt respectively.

The box-shaped pipe stull 50 and 52 that bearing

cylinder

34 and 36 usefulness are welded with it forms a firm rigidity square frame.Rotor shaft 17 is connected with hub, shown in Fig. 3 and 4.Mounting bracket 54 will wave hub assembly parts 55 and box-shaped pipe 50 and 52 is rigidly connected.A gear-box 60 is on bearing

cylinder

34 and 36 respective end.Quaternate spur wheel 60 is installed in the gear-box and rotates, shown in Fig. 1 and 4.Prototype pitch circle diameter is 9 inches.Two

actuation gears

62 and 64 are being transferred coaxial installation on oar axle 38 and 40.Eccentric mounting flange 42 is connected with spur wheel 62.Two

shaftgears

62 and 64 connect with a pair of driving gear 66 and 68 and to do transmission, the plane bias that they are bearing in the gear-box 60 and axis b and c form, as shown in Figure 4.

On the end in addition of bearing

cylinder

34 and 36, axis is connected by a rotation biasing member, and the identical crank throw of a pair of placement direction 70 and 72 is arranged in these parts, is rigidly connected with

accent oar axle

38 and 40 respectively.Crank throw 72 and eccentric mounting flange 44 cast solids can be cast when needing.Crank throw 70 and 72 outer end and hydraulic linear actuator 74 are done pivotally connected, and actuator 74 has cylinder body 76, do pivotally connectedly with crank throw 70, and piston rod 78 slides in cylinder, does pivotally connected with crank throw 72.In order to make design compact as far as possible, crank throw preferably stretches towards the circular mounting flange, and direction is identical with the knuckle core of gear-box 60, and as shown in Figure 2, linear actuators 74 can be established spring bias voltage propelling piece when needing.

Hydraulic system such as Fig. 5 letter are shown.Hydraulic pipe line passes with one heart towards gear-box 20 in rotor transmission shaft, connects by the gentle pressure accumulator of a swivel joint pipe fitting, and other assemblies are installed in the deflection loader 14, as shown in Figure 5.Just hydraulic fluid is freely led to oil groove when forwarding to valve on the closed position, make centrifugal force the complete feathering of blade.

Hydraulic system among Fig. 5 is used to control pitch actuator 74, makes two blades regulate about 70 ° between feathering and working state.During running, the accent oar moment that the airload on centrifugal force and the blade causes is tended to piston rod is extracted out from linear actuator.This moment increases with wind speed, and direction is identical with wind direction.A bladder air charged accumulator 80 is arranged, absorb the accent oar moment that piston rod 78 elongations cause and extrude the liquid of linear actuator.Gas-filling bag plays spring action, absorbs the power of aerodynamic moment, thereby the restoring moment that increases is provided, and blade is sent back on the working state.

Some element of hydraulic system is placed in the NEMA4 case (NEMA is a U.S. National Electrical Manufacturer Association) as shown in Figure 5

There are four kinds of programs in this system:

A. pressurized start program;

B. load is transferred pitch to feathering down;

C. transfer pitch to working state during off-load;

D. rapid feathering (instruction is stopped).

Shut-off valve 82 cuts out during energising, and electric-motor pump 84 startings increase to running pressure with system pressure.Gas spring pressure in the accumulator 80 and liquid stock balance, linear actuator 76 retreat on the starting position (in Fig. 5 and working state position opposite) fully.When reaching running pressure, pump 84 makes it motionless through pressure switch 86.Pump starting when needing is to keep the system pressure of pressure switch area requirement.But when pump quit work, check valve 88 and hydraulic system were isolated.

In program B (pitch turns to feathering under load), the accent oar moment of the centrifugal force when wind speed increases in the turbo driving and aerodynamic increase is tended to piston rod 78 is extracted out from linear actuator 76.The liquid that linear actuator is discharged will be passed through oil hydraulic circuit, suck accumulator 80, bleed valve 90 be arranged, quick-break device 92, the oil hydraulic circuit that passes through from turbine shaft 17 and swivel joint 94, quick-break device 96, check valve 98, quick-break device 100 and decompressor 102 in the loop.Liquid stock increase the gas spring pressure and the system pressure that will increase in the accumulator 80.The accumulator size requirement should be able to absorb the storage under the highest system pressure.Liquid from linear actuator inflow accumulator tends to the rotor blade feathering.

In program C when off-load (on the blade pitch change) to operating condition, the hydraulic fluid reverse flow.When the accent oar moment on the blade reduced because of wind speed, the gas elastic force in the accumulator 80 provided control force, and linear actuator 74 is returned on the working position.This control force is in operating mode B, because of length of spring compressed is stored.When spring when state of equilibrium is return, liquid is discharged from accumulator, by check valve 98, through identical oil hydraulic circuit, enters actuator by valve 104.

Program B and C often occur during turbo driving.Because flowage friction and actuator friction cause the loss of stored energy, just pump must be started, and keep the pressure in the system.

Program D(makes the rapid feathering of shutdown) be by with solenoid valve 82 outages, hydraulic fluid row is obtained to liquid storage tank 106.Because centrifugal force or aerodynamic force feathering moment, the liquid that linear actuator 76 is discharged by solenoid valve 82, enters liquid storage tank through check valve 98.The liquid stream of discharging from accumulator also is introduced into liquid storage tank.Pump 84 must be reset recovery system pressure after the shutdown.

Increase wind-force load and cause blade moment to rise on blade, it reverses and transfers the oar axle.This moment of torsion that increases will run into the resistance that linear actuators 74 more strengthens.Wind-force load is big more, and the control moment of blade is also big more, and blade just is more prone to feathering.

As among Fig. 6 about shown in the curve of this programme, the power curve of being done comprises the scope of 7 to 30 miles per hour wind speed.In linear actuators 74, increase a spring, can make the envelope of curve broadening of running.The shape of curve, peak output output flat segments curve and shutdown tilting section power curve are decided by that all the pitch that changes with wind speed changes program.Two recline pressure curves are represented the design standard of Passive Control, and Passive Control can adopt fluid power, or in the load control area, increase the combination of spring bias voltage.The blade pitch angle approximative value curve representation of Passive Control.

The blade pitch controller is a passive mechanical device, makes blade in transferring the oar degrees of freedom, seek the equilibrium position voluntarily when condition changes.Some accent oar moments are comprehensive, the pitch equilibrium code of decision rotor.Blade profile, biasing of blade thrust and the biasing of blade centrifugal force produce transfers oar moment, its vector and decision pitch equilibrium code, the pitch equilibrium code determines the power curve feature again, the size of each moment and variation, can be by the scrupulous blade center of gravity axis of placing, the biasing of control axis and aerodynamic force axis etc. and in advance to change.The Eulerian angle of axis of runner blade are inswept cone angle, when performing an analysis and wave all no less importants of angle △ 1 and △ 3 of dynamically pulling back.

This passive rotor control system utilize wind-force and blade intrinsic be used to power, change the pitch of rotor automatically, at fitful wind, strong wind and zero load protection turbine down.Select suitable gas spring, can be with the rotor pitched on given position, to obtain maximum power curve.Reliability that the automatic rotor hub provides and level of security can be saved break, but the weathercock manually-operable.

100 kilowatts of wind turbine systems for utilizing pitch control hub to design that the application discloses also have following mechanical technique to require:

Gear-box 20:

The speed ratio of two outputs is 25: 1 and 37.5: 1,

Full-load efficiency 95%

Low starting torque

First order planetary pinion

The second level spiral gear that dual output is arranged

The mono-directional overrun clutch of output

Two seal structures

Continuous oil-lubricated bearing

Generator:

100 kilowatts 20 kilowatts of power

1800 rev/mins 1800 rev/mins of rotating speeds

Pattern induction type induction type

480 alternating voltages, 480 alternating voltages

Power factor 0.95 0.85

Efficient 94% 91%

Pedestal 405 worm gear drives 284 worm gear drives

The drip-proof type drip-proof type

Structure H class H class

Deflection driven:

Drive deflection efficiency 4/ per second

The inertia structure that hypervelocity is arranged

Gear ratio 800: 1

1/2 horsepower of reversible inductor motor

The gear of transferring gear 62 on the oar axle and 64 the most handy hot hardenings to handle, AGMA(AGMA) the tolerance level is 11.Preferably these gears are being transferred hot jacket installation on the oar axle, the mounting flange of rotor blade is done adjustable installation with circular cone anchor clamps (not shown) on gear and axle, and the adjustable pine of anchor clamps makes blade can do ten/once " timing ", tightens then.But idler gear push-and-pull and rotation are to mesh new tooth.Because idler gear is replaceable, so can use the metal manufacturing softer, adapt to wearing and tearing than end gear, preferably free gear is installed on the eccentric part for ease of regulating.

The extreme stress alternation of dimensional range double-leaf wind turbine during the design of this hub can be handled, dimensional range are 50 to 80 feet.Leaf weight increases with the cube of radius.Gravity load on hub and the blade is when blade rotates the rotation of sub-axis, with the change in orientation of blade.In addition, because the center of gravity of blade is at the rear of transferring the oar axis, the gravity item has the less important alternation effect relevant with angle to the pitch angle.The loading off-load of this alternation is born by the design of rigid mount hub.

With the angular velocity square centrifugal force item that is directly proportional, more important than aerodynamic force item in design, rotating speed is transferred in the oar moment at blade reflected.

If needed, the different accumulator of available some pressure, available one or more actuators are handled different load ranges.Yet single actuator/single accumulator can show as all pitch controlling Design of summary of an exquisiteness.

Except that normal operation shown in Figure 6, pitch control hub also can compensate the loss of fitful wind and electric load.Fitful wind is reflected as because the increase of the nose-down pitching moment that the control axis bias causes on blade.This just causes the corresponding direct variation of propeller pitch angle, by blade be used to the power correction, discharge the moment of flexure of blade.The passive spring assembly of pitch control hub can not produce the instantaneous peak value moment of flexure of high torque peak and blade, and make it to reduce by the corresponding passive release of fitful wind load.

Just produce the corresponding hypervelocity of rotor along with the reduction of load.The hypervelocity that the design of passive type rotor also can cause load decline is controlled in the safety margin.At last, use passive pitch control hub also can save complicated electronic control logical circuit, the sensor that cooperatively interacts and be difficult to check and the feedback loop of running program complexity.With telescopic hydraulic pressure leverage, form direct and effective override capability at blade pitch load and gas spring chien shih, further improve the reliability of system.Feathering by blade provides automatic and manual shutdown function, just need not increase braking member or control unit.

Above-mentioned embodiment purpose is only for narrating not for to limit.Can do many variations and increase and decrease to the system that discloses and not break away from the principle and the spirit of invention.For example can be to spur

wheel

62,64,66 and 68 power train changes on demand, produces and the direct-connected contrary rotation of blade.And train of gearings and linear actuators can change along the position of transferring oar axis b and c.If any enough spaces, also power train can be placed on other positions, for example be placed on hub in the heart, one (as shown) or a plurality of linear actuators are connected with crank throw on the blade axle head that stretches out the bearing cylinder.Also can do other modification to hydraulic system.A for example available double acting cylinder is initiatively shifted blade onto all-cis oar state when needing.In any case scope of the present invention is decided by the accompanying Claim book.

Claims

1, a kind of wind turbine pitch control wheel hub comprises:

A housing has the parallel blade of spacing to transfer the oar axis to be limited in the plane with a pair of, and near the rotor axis this plane and this two mid point of transferring between the oar axis intersects,

A machine control unit, with the starting pitch angle bias voltage of sharf to a demarcation, bearing the total load of blade, the pitch angle during the decision running initiatively,

It is characterized in that this propeller boss also comprises:

A pair of sharf is bearing on this shell, does part rotation at least around the corresponding oar axis of transferring,

A train of gearings (device) two is transferred between oar axis (in a side of this rotor axis) and is laterally connected at this, this sharf is directly connected do contrary rotation, bearing the stress alternation of blade, and the pitch angle of two blades is interrelated,

Each sharf has the crank of a circumferentially extending,

The device that connects between this crank changes the relative displacement of crank with blade loads, do controllable variation.

This machine control unit that connects between this crank has a linear actuators, and its cylinder body and a crank are done pivotally connected, and a piston rod and another crank are done pivotally connected.

2, hub according to claim 1, it is characterized by this train of gearings has quaternate coplane spur wheel.

3, as the hub as described in the claim 2, it is characterized by four spur wheels has two driving gears, and each transfers coaxial installation on the oar axle corresponding, has at least two driving gears and driving tooth crop rotation to be in transmission connection.

4, hub according to claim 1, it is characterized by this linear actuators is oil hydraulic cylinder.

5, hub according to claim 1, an and hydraulic system is arranged in addition, wherein have pressurization device and with the oil hydraulic circuit of this rotor axis coaxial line, this pressurization device is connected with this oil hydraulic cylinder.

6,, it is characterized by this pressurization device and this rotor axis relative fixed as the hub as described in the claim 5.

7, as the hub as described in the claim 6, it is characterized by this hydraulic system has on-off valve device in circuit apparatus for hydraulic in addition, so that make manual feathering.

8, as the hub as described in the claim 4, it is characterized by this linear actuators has spring-loaded.

9, hub according to claim 1, and a pair of circular blade mounting flange is arranged in addition respectively determines a blade installation Flange Plane, has device that each mounting flange is connected with the respective vanes eccentric shaft, the Flange Plane axis of laterally sizing mixing, and the center-biased of blade flange.

10, as the hub as described in the claim 9, it is characterized by each blade installation flange at same direction upper offset, crank roughly stretches to the axis of respective vanes flange.

11, a kind of wind turbine feather is controlled the wind turbine system, comprising:

A deflection loader,

A rotor wherein has a hub, has the blade of two variablepistons at least, be installed on the hub on the accent oar axle of skew,

Rotating shaft device is done rotatable the connection with this rotor with this loader,

It is characterized in that this system also comprises:

A hydraulic actuator (device) is directly pivotally connected between this two accent oar axle, thereby corresponding blade pitch load directly acts on mutually by this actuator,

Inflation hydraulic accumulator on this loader, the pressure oil pressurization to the inside,

The hydraulic pressure tube connecting device guides this hydraulic fluid, and this actuator devices is connected with this accumulator apparatus.

12,, and there is device will transfer the oar axle to do 1: 1 contrary rotation in addition as the system as described in the claim 11.

13, as the system as described in the claim 11, and control valve unit is arranged in addition, discharge the pressure in this hydraulic pressure tube connecting device according to halt instruction.

14, as the system as described in the claim 13, and the electric-motor pump device is arranged in addition, hydraulic fluid is injected this accumulator apparatus,, be elevated to predetermined working pressure by this hydraulic pressure leverage.

15,, is connected and have pressure switch apparatus and this hydraulic pressure to take in addition, to this energising of electric-motor pump device or outage, maintenance rated working pressure as the system as described in the claim 14.

16, as the system as described in the claim 13, it is characterized by this control valve unit is solenoid valve.

17, as the system as described in the claim 11, it is characterized by this tube connecting device essentially concentric in this driveline and pass.

18, hub according to claim 1 is characterized by this train of gearings and connects this axle in this rotor axis one side, and this linear actuators is connected this rotor axis this between centers of side in addition.

19, hub according to claim 1, it is characterized by has an elastomeric hub that waves in this housing.