JP2005030264A - Pitch angle control device of windmill blade - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily and securely rotate a windmill blade 11 into a feathering state when a supply circuit 77 for supplying a fluid to a fluid servomotor 37 fails. <P>SOLUTION: Since an accumulator 108 storing the high-pressure fluid of a specified pressure is connected to the supply circuit 77, even when the supply circuit 77 fails and the high-pressure fluid cannot be supplied to the fluid servomotor 37, the windmill blade 11 can be easily and securely rotated into the feathering state by supplying the high-pressure fluid from the accumulator 108 to the fluid servomotor 37. In addition, since the accumulator 108 is connected to the supply circuit 77, normally the high-pressure fluid is supplemented from the supply circuit 77 thereto, and the maintenance of the accumulator can be easily performed. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a pitch angle control device for controlling a pitch angle of a wind turbine blade in a wind turbine used for wind power generation.
[0002]
[Prior art]
[Patent Document 1]
JP 2001-99045 A
[0003]
As a conventional wind turbine blade pitch angle control device, for example, the one described in Patent Document 1 is known. This is an electric servo motor whose output shaft rotates when energized, and a transmission mechanism comprising a plurality of bevel gears for transmitting the rotation of the output shaft of the electric servo motor to the wind turbine blade and rotating the wind turbine blade synchronously. And. The electric servo motor is normally servo-controlled by a control signal output from a comparator based on an operation signal and a detection signal from an encoder or the like connected to the output shaft of the electric servo motor.
[0004]
However, since the electric servo motor as described above has a small output torque, there is a problem that the entire control device becomes large. In order to solve such a problem, a large torque is output while being small. It is conceivable to use a fluid servomotor that can be used for rotating the windmill blade and to servo-control the fluid servomotor by a servo control valve.
[0005]
[Problems to be solved by the invention]
Here, the supply circuit for supplying fluid to the fluid servo motor as described above may fail, for example, the electric motor for driving the fluid pump may stop due to a power failure. It becomes impossible to control the pitch angle of the blade. Especially, when the pitch angle of the windmill blade is set for weak wind, the windmill will rotate at high speed when the wind circuit blows and then strong wind blows. There is a problem that it becomes dangerous.
[0006]
An object of the present invention is to provide a pitch angle control device for a wind turbine blade that can easily and reliably rotate the wind turbine blade to a feathering state when a supply circuit that supplies fluid to the fluid servomotor fails. To do.
[0007]
[Means for Solving the Problems]
Such an object is a pitch angle control device for a wind turbine blade in which a pitch angle is controlled by rotating a plurality of wind turbine blades whose inner ends in the radial direction are rotatably connected to a rotor head. And a fluid servomotor that rotates when the high-pressure fluid is supplied to rotate the windmill blade, and a pair of supply / discharge passages connected to the fluid servomotor, a supply circuit, and a discharge circuit, A servo control valve having a spool that moves in the axial direction to supply high-pressure fluid from a supply circuit to a fluid servomotor through one of the supply / discharge passages, and servo control based on feedback output and operation signals from the fluid servomotor Servo control means for servo-controlling the fluid servomotor by moving the valve spool in the axial direction, and a high-pressure fluid of a predetermined pressure connected to the supply circuit This is achieved by supplying a high-pressure fluid from the accumulator to the fluid servomotor through a servo control valve and a supply / exhaust passage and rotating the wind turbine blade to a feathering state when the supply circuit fails. it can.
[0008]
In the present invention, since the accumulator for storing the high-pressure fluid having a predetermined pressure is connected to the supply circuit as described above, when the supply circuit fails and the high-pressure fluid cannot be supplied, the servo control valve, the supply / discharge passage By supplying a high-pressure fluid from the accumulator to the fluid servomotor through the windmill blade, the windmill blade can be easily and reliably rotated to the feathering state. As a result, even when the pitch angle of the windmill blade is set for a weak wind, the supply circuit breaks down, and even if a strong wind comes after that, the windmill hardly rotates and is safe. Since this accumulator is connected to the supply circuit, the high-pressure fluid is replenished from the supply circuit at normal times. As a result, no fluid replenishment work is required and maintenance is facilitated.
[0009]
Here, a feathering fluid motor that rotates the windmill blade in the event of a failure of the supply circuit described above is provided separately, and the high-pressure fluid from the accumulator is supplied to the feathering fluid motor to rotate the windmill blade to the feathering state. It is possible to move it. However, if this is done, the structure becomes complicated and the manufacturing cost is also expensive, but if the fluid servo motor that rotates the windmill blade at the normal time is used as it is for rotating to the feathering state as in the present invention, The above-described feathering fluid motor is not required, the structure is simplified, and the manufacturing cost can be reduced.
[0010]
Further, if a part of the servo control means is composed of mechanical parts as described in claim 2, it becomes strong against lightning strikes and is hardly affected by it.
Furthermore, if constituted as in claim 3, the accumulator can be shared by the fluid servomotor and the emergency fluid motor, the structure can be simplified and the manufacturing cost can be reduced.
Further, when configured as described in claim 4, when the windmill blade is rotated to just before the feathering state, the high-pressure fluid in the accumulator can be discharged, and the application of rotational force to the windmill blade can be terminated. Thereby, the rotational speed when a windmill blade reaches | attains a feathering state can be reduced.
Furthermore, if it comprises as described in Claim 5, although the structure is simple, the protrusion amount from a housing can be made small and size reduction is attained.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
1 and 2, reference numeral 11 denotes a plurality of windmill blades that extend in the radial direction and are spaced at equal angles in the circumferential direction. The radial inner ends of the windmill blades 11 are cylindrical and rotatable to the windmill body. It is rotatably connected to a supported hollow rotor head (not shown). The rotor head is connected to a speed increaser and a generator (not shown). As a result, when the wind turbine blade 11 and the rotor head rotate around the rotation axis of the rotor head, the generator generates (wind) power generation. To do. Here, an internal gear 12 is formed on the inner periphery of the inner end portion in the radial direction of each wind turbine blade 11.
[0012]
Reference numeral 15 denotes a plurality of pitch angle control devices (the same number as the wind turbine blades 11) for controlling the pitch angle, that is, the mounting angle of the wind turbine blades 11 with respect to the rotor head by rotating the wind turbine blades 11, and each pitch angle control device. Reference numeral 15 denotes a planetary gear speed reducer, here an eccentric oscillating speed reducer 17 attached to one side of a fixed cover 16 fixed to the inner periphery of the rotor head. The speed reducer 17 has a case 20 having a substantially cylindrical shape. A carrier 21 is accommodated in the case 20, and a large number of internal teeth pins 22 as internal teeth are provided on the inner periphery thereof. . Reference numeral 23 denotes an output shaft integrally connected to one end of the carrier 21, and the output shaft 23 and the carrier 21 are rotatably supported by the case 20.
[0013]
Reference numeral 26 denotes a plurality of, here two, pinions housed in the case 20, and these pinions 26 are arranged in parallel in the axial direction. Further, these pinions 26 have external teeth (not shown) whose number of teeth is slightly smaller than the number of internal teeth pins 22 on the outer periphery, and these external teeth are out of phase with each other by 180 degrees in the adjacent pinion 26. It meshes with the internal tooth pin 22.
[0014]
The pinion 26 has a plurality of through holes 27, and each of the through holes 27 has an eccentric portion 28 a formed at the center in the axial direction of the crankshaft 28 rotatably supported by the carrier 21. It is inserted with the needle bearing 29 interposed. Reference numeral 30 denotes an input gear connected to the other end of each crankshaft 28, and these input gears 30 are engaged with an external gear 31 fixed to a rotating shaft of a fluid servo motor described later.
[0015]
When the rotational driving force is transmitted to the input gear 30 through the external gear 31 and the crankshaft 28 rotates synchronously in the same direction, the eccentric portion 28a rotates eccentrically in the through hole 27 and rotates the pinion 26 eccentrically (revolves). At this time, the case 20 is stationary, and the number of external teeth of the pinion 26 is slightly smaller than the number of internal teeth pins 22, so that the carrier 21 and the output shaft 23 rotate at a low speed. The above-described case 20, carrier 21, internal pin 22, pinion 26, crankshaft 28, and input gear 30 as a whole reduce the rotation of the fluid servomotor with a large reduction ratio and output it to the output shaft 23. 17 is constituted.
[0016]
Reference numeral 34 denotes an external gear connected to the output shaft 23, and the external gear 34 meshes with the internal gear 12 of the wind turbine blade 11. Then, after the rotation of the fluid servo motor is decelerated by the speed reducer 17, it is transmitted to the windmill blade 11, and the pitch angle is changed by rotating the windmill blade 11.
[0017]
In FIGS. 1, 2, and 3, reference numeral 37 denotes a fluid servomotor attached to the other side of the fixed cover 16, and this fluid servomotor 37 is composed of a swash plate type fluid motor here. The fluid servomotor 37 has a motor case 39 in which a storage chamber 38 is formed. A rotary shaft 40 stored in the storage chamber 38 is rotatably supported by the motor case 39, and the rotation shaft The external gear 31 is fixed to the front end portion (one end portion) of 40 as described above. Reference numeral 41 denotes a cylindrical cylinder block stored in the storage chamber 38. The rotary shaft 40 is inserted into the cylinder block 41 and splined. Plungers 43 are slidably inserted into the plurality of cylinder holes 42 formed in the cylinder block 41, and shoes 44 are connected to the tips (one ends) of the plungers 43.
[0018]
A timing plate 47 is interposed between a cylinder block 41 and a housing described later. A pair of supply / discharge holes 46 formed in the timing plate 47 includes a cylinder hole 42 and a pair of supply / discharge passages 48 and 49. Are connected to each other. Reference numeral 50 denotes a substantially ring-shaped swash plate stored in the storage chamber 38. An inclined surface 50a is formed on the other end surface of the swash plate 50, and the shoe 44 is in sliding contact with the inclined surface 50a. When high-pressure fluid is supplied from the supply / discharge passages 48 and 49 to the cylinder hole 42 through the supply / discharge holes 46 of the timing plate 47, the cylinder block 41 and the rotating shaft 40 rotate.
[0019]
Further, two flat surfaces are formed on one end surface of the swash plate 50, and a fulcrum member (not shown) is disposed on the boundary between the flat surfaces. Reference numeral 51 denotes a cylinder chamber formed on one end surface of the storage chamber 38. In this cylinder chamber 51, a tilting piston 52 in contact with one end surface of the thin portion of the swash plate 50 is slidably stored. . Then, when the high-pressure fluid is supplied to the cylinder chamber 51 or the fluid is discharged from the cylinder chamber 51, the tilting piston 52 protrudes or retracts. At this time, the swash plate 50 has the fulcrum member. Is tilted between two tilt positions, a high-speed tilt position and a low-speed tilt position. Due to such a change in the tilting position of the swash plate 50, the stroke of the plunger 43 in the cylinder block 41 is changed to two stages, whereby the rotational speed of the rotary shaft 40 and the cylinder block 41 is increased to two stages of high and low speed. A wide range of rotation speed control can be performed.
[0020]
The motor case 39, the rotating shaft 40, the cylinder block 41, the plunger 43, the shoe 44, the timing plate 47, the swash plate 50, and the tilting piston 52 constitute the fluid servomotor 37 as a whole. When the high pressure fluid is supplied, the rotating shaft 40 rotates. The rotation of the rotating shaft 40 is decelerated by the speed reducer 17 and then transmitted to the windmill blade 11 to rotate the windmill blade 11. The fluid servomotor 37 is connected to the pair of supply / discharge passages 48 and 49 as described above.
[0021]
55 is a negative brake that applies a braking force to the fluid servomotor 37 when the fluid servomotor 37 is stopped. The negative brake 55 includes a plurality of inner friction plates 56 that are splined to the outer periphery of the cylinder block 41; A plurality of outer friction plates 57 are splined to the inner periphery of the storage chamber 38 of the motor case 39. In the negative brake 55, when the supply of high-pressure fluid to the brake passage 58 is stopped, the outer friction plate 57 is placed on the inner side by a spring (not shown) disposed between the piston 59 and a housing described later. When pressed against the friction plate 56 to apply a braking force to the cylinder block 41, when the high pressure fluid is supplied to the brake passage 58 and the piston 59 moves to the other side while compressing the spring, the outer friction plate 57 is moved to the inner side. The cylinder block 41 is allowed to rotate away from the friction plate 56.
[0022]
In FIGS. 1, 2, 3, and 4, reference numeral 61 denotes a housing fixed to the other end surface of the fluid servomotor 37, and the housing 61 has a penetrating cross section extending in a direction perpendicular to the rotation axis 40 of the fluid servomotor 37. A circular spool hole 62 is formed. The front end opening of the spool hole 62 is closed by a front end cap 63 fixed to the housing 61, while the rear end opening is closed by a rear end cap 64 fixed to the housing 61.
[0023]
A spool 67 is slidably inserted into the spool hole 62. The spool 67 can move in the spool hole 62 in the axial direction while being prevented from rotating by a key 68 attached to the tip cap 63. . On the outer periphery of the spool 67, two annular grooves 67a and 67b that are axially separated from the front end side toward the rear end side are sequentially formed. The aforementioned spool hole 62, spool 67, and key 68 constitute a servo control valve 69 having a spool 67 movable in the axial direction as a whole.
[0024]
Reference numeral 72 denotes a fluid pump. The fluid pump 72 is always driven by an electric motor 73 to suck fluid from the tank 74 through the suction passage 75 and discharge the fluid as a high-pressure fluid to the supply passage 76. The supply passage 76 is connected to the servo control valve 69, specifically, the spool hole 62. As a result, high-pressure fluid is guided from the fluid pump 72 to the servo control valve 69 through the supply passage 76. The fluid pump 72, the electric motor 73, the suction passage 75, and the supply passage 76 described above constitute a supply circuit 77 that supplies high-pressure fluid to the servo control valve 69 as a whole.
[0025]
Reference numeral 78 denotes a discharge circuit (discharge passage) that connects the tank 74 and the servo control valve 69, specifically, the spool hole 62, and this discharge circuit 78 guides the low-pressure return fluid flowing out from the servo control valve 69 to the tank 74. Thus, the servo control valve 69 is interposed between the pair of supply / discharge passages 48 and 49 connected to the fluid servomotor 37, the supply circuit 77 and the discharge circuit 78, and the spool 67 moves in the axial direction. As a result, the high-pressure fluid is supplied from the supply circuit 77 to the fluid servomotor 37 through one of the supply / discharge passages 48 and 49, and the fluid servomotor 37 is rotated forward or backward while performing servo control.
[0026]
That is, when the spool 67 of the servo control valve 69 is stopped at the position indicated by the solid line in FIG. 4, the servo control valve 69 is positioned at the neutral position, and therefore the supply and discharge passages 48 and 49 are supplied by the spool 67. Although the circuit 77 and the discharge circuit 78 are disconnected, when the spool 67 moves to the rear end side, the servo control valve 69 is switched to the parallel flow position, and the supply / discharge passage 48 and the supply circuit 77 are connected to the annular groove 67b. In addition, the supply / discharge passage 49 and the discharge circuit 78 communicate with each other through the annular groove 67 a, whereby high-pressure fluid from the fluid pump 72 is supplied to the fluid servomotor 37 via the servo control valve 69 and the supply / discharge passage 48. Is done.
[0027]
On the other hand, when the spool 67 moves to the front end side, the servo control valve 69 is switched to the cross flow position, and the supply / discharge passage 48 and the discharge circuit 78 pass through the annular groove 67b, and the supply / discharge passage 49 and the supply circuit 77 The high-pressure fluid from the fluid pump 72 is supplied to the fluid servomotor 37 via the servo control valve 69 and the supply / discharge passage 49. In this way, the fluid servomotor 37 operates while being servo-controlled by the servo control valve 69, and the rotating shaft 40 rotates forward and backward.
[0028]
A notch 81 is formed in the spool 67 between the annular grooves 67a and 67b, and a thrust bush 83 for rotatably supporting a substantially cylindrical sleeve 82 is housed and fixed in the notch 81. As a result, the sleeve 82 is rotatably supported by the spool 67 via the thrust bush 83. Reference numeral 84 denotes a loose fitting hole formed on the central axis of the spool 67, and a loosely fitting screw shaft 86 having a screw 85 on the outer periphery of the central portion is loosely fitted into the loose fitting hole 84. A screw 87 is formed on the inner periphery of the sleeve 82 and is a screw. The female screw 87 is screwed with a male screw 85 of the screw shaft 86. As a result, when the screw shaft 86 rotates, the sleeve 82 moves integrally with the spool 67 in the axial direction by the screw action of the male screw 85 and the female screw 87.
[0029]
Reference numeral 90 denotes a control motor such as a pulse motor attached to the rear end surface of the housing 61. An operation signal (pulse) is input to the control motor 90 from a controller 91 such as a CPU. The control motor 90 has an output shaft (not shown) that is coaxial with the screw shaft 86 and is rotated by the operation signal, and this output shaft is connected to the rear end portion of the screw shaft 86 that penetrates the rear end cap 64. ing. The control motor 90 generates a rotational driving force corresponding to the input operation signal, and applies the rotational driving force to the screw shaft 86 of the conversion moving means described later.
[0030]
Reference numeral 94 denotes a loose fitting hole formed in the housing 61 and coaxial with the rotary shaft 40 of the fluid servomotor 37, and the other end opening of the loose fitting hole 94 is closed by a receiving member 95. Reference numeral 96 denotes a transmission shaft loosely fitted in the loose fitting hole 94. One end of the transmission shaft 96 is splined to the other end of the rotary shaft 40, while the other end is connected to the receiving member 95. It is rotatably supported. As a result, the transmission shaft 96 can rotate integrally with the rotating shaft 40. A helical gear 99 is integrally formed on the outer periphery of the central portion of the transmission shaft 96, and the helical gear 99 meshes with a helical gear 100 formed on the outer periphery of the central portion of the sleeve 82. Here, since the rotation axis of the sleeve 82 and the rotation axis of the transmission shaft 96 are orthogonal to each other in a twisted state, the helical gears 99 and 100 constitute an orthogonal helical spiral gear.
[0031]
As a result, when the screw shaft 86 rotates to the right by the operation of the control motor 90, the sleeve 82 is restricted from rotating integrally with the screw shaft 86 by the helical gears 99, 100. In this case, it moves toward the rear end side, so that the spool 67 also moves in the axial direction (rear end side) integrally with the sleeve 82 and the servo control valve 69 is switched to the parallel flow position. The passage 48 and the supply circuits 77 communicate with each other, and the supply / discharge passage 49 and the discharge circuits 78 communicate with each other. On the other hand, when the screw shaft 86 rotates counterclockwise, the sleeve 82 moves in the axial direction (front end side) while rotating rightward. As a result, the spool 67 and the sleeve 82 move in the axial direction (front end side) and servo. The control valve 69 is switched to the cross flow position so that the supply / discharge passage 48 and the discharge circuits 78 communicate with each other and the supply / discharge passage 49 and the supply circuit 77 communicate with each other.
[0032]
The sleeve 82, the thrust bush 83, the screw shaft 86, and the helical gear 100 as a whole, when the rotational driving force according to the operation signal is applied from the control motor 90, the rotational driving force is converted into the axial movement force. Conversion converting means 101 is configured to convert and move the spool 67 of the servo control valve 69 in the axial direction. Further, the transmission shaft 96 and the helical gear 99 described above constitute a mechanical transmission means 102 connected to the fluid servomotor 37, more specifically, the rotary shaft 40, and the mechanical transmission means 102 is the fluid. The rotational force of the servo motor 37 is fed back to the helical gear 100 of the conversion moving means 101, and the spool 67 is moved in the direction opposite to the moving direction by the control motor 90.
[0033]
The aforementioned supply / discharge passages 48 and 49, servo control valve 69, supply circuit 77, discharge circuit 78, control motor 90, conversion moving means 101, mechanical transmission means 102 as a whole are feedback output and operation from the fluid servomotor 37. Servo control means 103 is configured to servo-control the fluid servomotor 37 by moving the spool 67 of the servo control valve 69 in the axial direction based on the signal. Thus, if a part of the servo control means 103 is composed of mechanical parts such as the control motor 90 and the conversion moving means 101 housed in the housing 61 and the mechanical transmission means 102, it is resistant to lightning strikes, and almost no influence is exerted. You will not receive it.
[0034]
When the spool 67 of the servo control valve 69 is switched from the neutral position to the parallel flow or cross flow position by the control motor 90, the high-pressure fluid discharged from the fluid pump 72 is supplied to the supply passage 76 or one of the supply / discharge passages. The fluid servomotor 37 is supplied to the fluid servomotor 37 through 48 and 49, and the fluid servomotor 37 is operated. At this time, the rotation of the rotary shaft 40 of the fluid servomotor 37 is transmitted as feedback force to the conversion movement means 101 by the mechanical transmission means 102, so that the spool 67 moves in the direction opposite to the movement direction by the control motor 90 and is neutral. The fluid servomotor 37 is servo-controlled by trying to return to the position. When the rotary shaft 40 rotates while the fluid servomotor 37 is servo-controlled in this way, this rotation is transmitted to the speed reducer 17 and decelerated at a high ratio, and then transmitted to the windmill blade 11 to rotate the windmill blade 11. The pitch angle is controlled.
[0035]
Reference numeral 104 denotes a relief valve that returns the high pressure fluid discharged from the fluid pump 72 to the tank 74, and reference numeral 105 denotes a prevention circuit that prevents cavitation in the supply / discharge passages 48 and 49. Reference numerals 106 and 107 are check valves which are interposed in the supply circuit 77, specifically in the middle of the supply passage 76 and permit only the flow of fluid from the fluid pump 72 to the servo control valve 69. Supply between these check valves 106 and 107 An accumulator 108 for storing a predetermined high-pressure fluid is connected to the circuit 77 (supply passage 76). Among these check valves, the check valve 106 is a tank in which high-pressure fluid is supplied from the accumulator 108 through the supply passage 76 and the fluid pump 72. The situation where it flows back to 74 is prevented. Since this accumulator 108 is connected to the supply circuit 77 (supply passage 76), the high-pressure fluid discharged from the fluid pump 72 is always replenished, and the internal pressure is always maintained at a predetermined high pressure.
[0036]
Reference numeral 111 denotes a swash plate type emergency fluid motor attached to the front end surface of the housing 61, and the output shaft of the emergency fluid motor 111 is connected to the front end of the screw shaft 86. As a result, the emergency fluid motor 111 is disposed on the opposite side surface (front end surface, rear end surface) of the housing 61 which is 180 degrees away from the control motor 90. Compared with the case where the two are stacked on one side of the housing, the projecting amount from the housing 61 can be reduced while simplifying the structure, and the size can be reduced.
[0037]
An inflow passage 112 connects the emergency fluid motor 111 and the accumulator 108, and an outflow passage 113 connects the emergency fluid motor 111 and the tank 74. In the middle of these inflow and outflow passages 112, 113, in other words, an open / close valve 114 made up of an electromagnetic valve is interposed between the accumulator 108 and the emergency fluid motor 111. The on-off valve 114 is in a closed position during normal energization to block the flow of high-pressure fluid from the accumulator 108 to the emergency fluid motor 111. However, the supply circuit 77, for example, the electric motor 73, When an emergency occurs when the control motor 90 or the like breaks down due to disconnection or power failure, the energization is cut off simultaneously with the failure. As a result, the on-off valve 114 is switched to the open position to supply high-pressure fluid from the accumulator 108 to the emergency fluid motor 111 through the inflow passage 112, and the emergency fluid motor 111 is operated to the screw shaft 86 of the conversion moving means 101. A rotational driving force is applied.
[0038]
Reference numeral 115 denotes a flow rate adjusting valve interposed in the inflow passage 112 between the on-off valve 114 and the accumulator 108. The flow rate adjusting valve 115 controls the flow rate of the high-pressure fluid flowing through the inflow passage 112, thereby enabling an emergency fluid motor. The rotation speed of the output shaft 111 is controlled. As a result, when the on-off valve 114 is switched to the open position, the emergency fluid motor 111 has the screw shaft of the conversion moving means 101 at a rotational speed corresponding to the high-pressure fluid from the accumulator 108 whose flow rate is controlled by the flow rate adjusting valve 115. 86 is rotated. Then, when the servo control valve 69 is switched from the neutral position to the flow position by the rotation of the screw shaft 86 by the emergency fluid motor 111 as described above, the high-pressure fluid is transferred from the accumulator 108 to the servo control valve 69, one of the supply / discharge passages 48. 49, 49 is supplied to the fluid servomotor 37, whereby the windmill blade 11 is easily and reliably rotated to the feathering state (the state where the windmill blade 11 is parallel to the wind direction).
[0039]
In this way, the emergency fluid motor 111 that is connected to the accumulator 108 and can apply a rotational driving force to the conversion moving means 101, and the on-off valve 114 interposed between the accumulator 108 and the emergency fluid motor 111, When the supply circuit 77 and the control motor 90 fail, the on-off valve 114 is opened and a high-pressure fluid is supplied from the accumulator 108 to the emergency fluid motor 111, whereby the emergency fluid motor 111 is rotationally driven to the conversion moving means 101. If force is applied, the accumulator 108 can be shared by the fluid servomotor 37 and the emergency fluid motor 111, and the structure can be simplified and the manufacturing cost can be reduced.
[0040]
Reference numeral 118 denotes a connection path having one end connected to the accumulator 108 via the inflow path 112 and the other end connected to the tank 74. The connection path 118 is normally closed, but the valve opening force is When received, a discharge valve 119 for opening the high-pressure fluid stored in the accumulator 108 and discharging the high-pressure fluid to the tank 74 is interposed. Reference numeral 120 denotes a valve-opening cam attached to the radially inner end of the windmill blade 11. When the windmill blade 11 rotates toward the feathering state by the operation of the fluid servomotor 37, the valve-opening cam 120 is rotated. When the wind turbine blade 11 gradually approaches the exhaust valve 119 and rotates until just before the feathering state, the exhaust valve 119 engages with the exhaust valve 119 and applies a valve opening force to the exhaust valve 119.
[0041]
As described above, when the wind turbine blade 11 is rotated until just before the feathering state by using the discharge valve 119 and the valve opening cam 120, the high-pressure fluid in the accumulator 108 is discharged to the tank 74 and imparts rotational force to the wind turbine blade 11. If the wind turbine blade 11 reaches the feathering state, the rotational speed when the wind turbine blade 11 reaches the feathering state can be reduced, whereby a stopper (not shown) when the wind turbine blade 11 reaches the feathering state can be reduced. Can be reduced.
[0042]
Next, the operation of one embodiment of the present invention will be described.
When the pitch angle of the windmill blade 11 is changed according to the change in the wind speed at the normal time, first, an operation signal (pulse) corresponding to the change in the wind speed is output from the controller 91 to the control motor 90, thereby The output shaft of the motor 90 and the screw shaft 86 rotate by an amount corresponding to the operation signal. Here, when the screw shaft 86 rotates clockwise, the sleeve 82 and the spool 67 move toward the rear end side, so that the servo control valve 69 is switched to the parallel flow position and the fluid pump is supplied through the supply circuit 77 and the supply / discharge passage 48. When the high-pressure fluid from 72 is supplied to the fluid servomotor 37 and the screw shaft 86 rotates counterclockwise, the sleeve 82 and the spool 67 move toward the tip side, so that the servo control valve 69 is switched to the cross flow position. The high pressure fluid from the fluid pump 72 is supplied to the fluid servomotor 37 through the supply circuit 77 and the supply / discharge passage 49.
[0043]
When the high-pressure fluid is guided to the fluid servomotor 37 in this way, the high-pressure fluid is supplied to one of the cylinder holes 42, and the plunger 43 in the cylinder hole 42 is pressed against the inclined surface 50 a of the swash plate 50. At this time, since the tip of the plunger 43 is in sliding contact with the inclined surface 50a via the shoe 44, the circumferential component of the pressing force acts on the plunger 43, whereby the plunger 43 and the shoe 44 are inclined to the inclined surface 50a. The plunger 43, the cylinder block 41, and the rotating shaft 40 are integrally driven and rotated in the forward direction or the reverse direction.
[0044]
Here, the rotation of the rotary shaft 40 described above is transmitted to the transmission shaft 96 to rotate the helical gear 99. Since the helical gear 116 meshes with the helical gear 100 of the sleeve 82, The sleeve 82 rotates in the direction opposite to the direction of rotation and the direction of movement by the control motor 90, and the spool 67 of the servo control valve 69 attempts to return toward the neutral position. In this way, the rotational force of the fluid servomotor 37 is fed back to the conversion moving means 101.
[0045]
As described above, when the fluid servomotor 37 is operated, the conversion moving means 101 is applied with the rotational force that causes the control motor 90 and the rotation shaft 40 to generate the reverse axial movement from the rotation shaft 40 to the spool 67. Is slightly delayed from the rotation of the output shaft of the control motor 90, the servo control valve 69 is held in the parallel flow position or the cross flow position.
[0046]
When the rotating shaft 40 rotates as described above, the rotation of the rotating shaft 40 is transmitted to the crankshaft 28 via the input gear 30, and the crankshaft 28 is rotated synchronously. At this time, the case 20 is stationary, and the number of external teeth of the pinion 26 is slightly smaller than the number of internal teeth pins 22, so that the rotation of the rotary shaft 40 is decelerated by the speed reducer 17 and the output shaft 23. Is output to the external gear 34 to rotate the external gear 34 at a low speed. Here, since the internal gear 12 formed on the wind turbine blade 11 is meshed with the external gear 34, the wind turbine blade 11 rotates in either direction by the rotation of the external gear 34, and the pitch angle thereof is changed. The In this manner, the fluid servomotor 37 is operated while being servo-controlled by the servo control valve 69 to apply the rotational force to the windmill blade 11, and the windmill blade 11 is moved to a position corresponding to the operation signal, that is, a position corresponding to the wind speed. Rotate until.
[0047]
The pitch angle of the windmill blade 11 is controlled within a range of 10 to 30 degrees during normal operation. When the wind becomes weak, the windmill blade 11 is rotated so that the pitch angle becomes small. The rotation of the rotor head is increased, and when the wind becomes stronger, the windmill blade 11 is rotated so as to increase the pitch angle to reduce the rotation of the rotor head, thereby avoiding the danger of strong winds. While trying to improve power generation efficiency. In the normal state as described above, since the accumulator 108 is constantly replenished with the high-pressure fluid discharged from the fluid pump 72, its internal pressure is a predetermined pressure.
[0048]
Here, when an emergency occurs when the supply circuit 77 (for example, the electric motor 73), the control motor 90, or the like breaks down due to disconnection or power failure, the high-pressure fluid is not supplied to the fluid servomotor 37 and the operation stops. When the pitch angle of the windmill blade 11 cannot be controlled, particularly when the above-described failure occurs when the pitch angle of the windmill blade 11 is set for a weak wind, and then a strong wind blows, the windmill Rotates at high speed and becomes dangerous. In such a case, since the energization to the on-off valve 114 is cut off simultaneously with the above-described failure, the on-off valve 114 is switched from the closed position to the open position, and from the accumulator 108 to the emergency fluid motor 111 through the inflow passage 112. High pressure fluid is supplied. At this time, since the amount of fluid flowing into the emergency fluid motor 111 is controlled by the flow rate adjusting valve 115, the rotation speed of the output shaft of the emergency fluid motor 111 is controlled to an appropriate value.
[0049]
When the output shaft of the emergency fluid motor 111 and the screw shaft 86 are rotated in this way, the sleeve 82 and the spool 67 are moved in the axial direction in the same manner as described above to move the servo control valve 69 from the neutral position to the flow position, for example, the parallel flow position. The supply / discharge passage 48, the supply passage 76, the supply / discharge passage 49, and the discharge circuit 78 are communicated with each other. As a result, the high-pressure fluid from the accumulator 108 is supplied to the fluid servomotor 37 through the servo control valve 69 and the supply / discharge passage 48, and the fluid servomotor 37 is operated, that is, the rotating shaft 40 is rotated.
[0050]
The rotation of the rotating shaft 40 of the fluid servomotor 37 is input to the speed reducer 17, and after being decelerated in the speed reducer 17 in the same manner as described above, it is output to the external gear 34 to rotate the external gear 34 at a low speed. . Thereby, the windmill blade 11 can be rotated toward a feathering state at the time of emergency when the supply circuit 77, the control motor 90, etc. have failed. Also at this time, the rotation of the rotary shaft 40 is fed back to the conversion moving means 101 through the mechanical transmission means 102 as described above.
[0051]
Then, when the windmill blade 11 is rotated until just before the feathering state, the valve opening cam 120 engages with the discharge valve 119 to apply a valve opening force to the discharge valve 119. As a result, the discharge valve 119 is switched from closed to open, and the high-pressure fluid in the accumulator 108 is discharged to the tank 74 through the inflow passage 112 and the connection passage 118, thereby stopping the supply of high-pressure fluid to the fluid servomotor 37. Thus, the turning power application to the windmill blade 11 is completed.
[0052]
Thereafter, the windmill blade 11 is rotated to the feathering state by the inertia and the wind load and is brought into contact with the stopper to restrict the rotation. As described above, the windmill blade 11 is rotated immediately before the windmill blade 11 reaches the feathering state. When the application is finished, the rotational speed when the wind turbine blade 11 reaches the feathering state is reduced, and the impact when the wind turbine blade 11 collides with the stopper is reduced.
[0053]
Thus, in this embodiment, since the accumulator 108 that stores high-pressure fluid of a predetermined pressure is connected to the supply circuit 77, when the supply circuit 77 fails and the high-pressure fluid cannot be supplied, the servo control valve 69, by supplying the high-pressure fluid from the accumulator 108 to the fluid servomotor 37 through the supply / discharge passage 48 or 49, the wind turbine blade 11 can be easily and reliably rotated to the feathering state. As a result, when the pitch angle of the windmill blade 11 is set for a weak wind, even if the supply circuit 77 breaks down and then a strong wind blows, the windmill hardly rotates and is safe. Become. Since the accumulator 108 is connected to the supply circuit 77, the high-pressure fluid is replenished from the supply circuit 77 in the normal state. As a result, no fluid replenishment work is required and maintenance is facilitated.
[0054]
Here, a feathering fluid motor for rotating the windmill blade 11 in the event of a failure of the supply circuit 77 described above is provided separately, and the high pressure fluid from the accumulator 108 is supplied to the feathering fluid motor to remove the windmill blade 11 from the feather. It is also conceivable to rotate to the ring state. However, if this is done, the structure becomes complicated and the manufacturing cost is high. However, as in this embodiment, the fluid servomotor 37 that rotates the wind turbine blade 11 during normal operation is used as it is for rotating to the feathering state. This eliminates the need for the above-described feathering fluid motor, simplifies the structure, and reduces the production cost.
[0055]
In the above-described embodiment, the case 20 of the speed reducer 17 is fixed, and the windmill blade 11 is rotated by rotating the carrier 21 and the external gear 34. However, in the present invention, the carrier is On the other hand, the wind turbine blade may be rotated by fixing the case to a fixed plate provided at the radially inner end of the wind turbine blade and transmitting the low speed rotation of the case directly to the wind turbine blade. In this way, the internal gear 12, the output shaft 23, and the external gear 34 are not required, the structure is simple and small, and the manufacturing cost can be reduced.
[0056]
In the above-described embodiment, the servo control means 103 is configured by combining mechanical parts such as the servo control valve 69, the supply circuit 77, the control motor 90, the conversion moving means 101, the mechanical transmission means 102, etc. In the invention, a control signal is output to the servo control valve based on a detection sensor such as an encoder that detects the rotation of the rotary shaft of the fluid servomotor, and an operation signal and a detection signal from the detection sensor, and the servo control valve is controlled. It may be configured from a comparator.
[0057]
Further, in the above-described embodiment, the fluid pump 72 is always operated. However, in the present invention, the fluid pump is intermittently operated while the accumulator is used as a fluid source when the fluid pump is not operated. May be used. In the above-described embodiment, an AC or DC motor such as a pulse motor is used as the control motor 90. However, in the present invention, a fluid motor may be used.
[0058]
【The invention's effect】
As described above, according to the present invention, when the supply circuit that supplies fluid to the fluid servomotor fails, the windmill blade can be easily and reliably rotated to the feathering state.
[Brief description of the drawings]
FIG. 1 is a circuit diagram showing an embodiment of the present invention.
FIG. 2 is a partially cutaway front view of the vicinity of a fluid servomotor and a speed reducer.
FIG. 3 is a front sectional view of the vicinity of a fluid servomotor and servo control means.
4 is a cross-sectional view taken along the line II in FIG. 3;
[Explanation of symbols]
11 ... windmill blade 15 ... pitch angle control device
37 ... Fluid servo motor 48, 49 ... Supply / discharge passage
61 ... Housing 67 ... Spool
69 ... Servo control valve 74 ... Tank
77 ... Supply circuit 78 ... Discharge circuit
90 ... Control motor 101 ... Conversion moving means
102 ... Mechanical transmission means 103 ... Servo control means
108 ... Accumulator 111 ... Emergency fluid motor
114 ... Open / close valve 118 ... Connection passage
119 ... Drain valve 120 ... Valve opening cam

Claims (5)

A pitch angle control device for a wind turbine blade that controls a pitch angle by rotating a plurality of wind turbine blades whose inner ends in a radial direction are rotatably connected to a rotor head. And a fluid servo motor that rotates when rotated to rotate the windmill blade, and is interposed between a pair of supply / discharge passages connected to the fluid servo motor, a supply circuit, and a discharge circuit, and moves in the axial direction. The servo control valve having a spool for supplying high-pressure fluid from the supply circuit to the fluid servomotor through any supply / discharge passage, and the servo control valve spool in the axial direction based on the feedback output and operation signal from the fluid servomotor And a servo control means for servo-controlling the fluid servomotor, and an accumulator connected to the supply circuit for storing high-pressure fluid of a predetermined pressure And a high pressure fluid is supplied from the accumulator to the fluid servomotor through a servo control valve and a supply / exhaust passage when the supply circuit fails, and the windmill blade is rotated to the feathering state. Wind turbine blade pitch angle control device. When the servo control means receives the rotational drive force, the servo control means converts the rotational drive force into an axial movement force to move the spool of the servo control valve, and rotationally drives the servo control valve according to the operation signal. , A control motor for applying the rotational driving force to the conversion movement means, and a mechanical transmission means for feeding back the rotation of the fluid servo motor to the conversion movement means and moving the spool in a direction opposite to the movement direction of the control motor. The pitch angle control apparatus of the windmill blade of Claim 1 comprised. An emergency fluid motor connected to the accumulator and capable of applying a rotational driving force to the conversion moving means, and an on-off valve interposed between the accumulator and the emergency fluid motor are further provided, and a supply circuit and control 3. A wind turbine blade according to claim 2, wherein when the motor fails, the on-off valve is opened and a high-pressure fluid is supplied from the accumulator to the emergency fluid motor so as to apply a rotational driving force from the emergency fluid motor to the conversion moving means. Pitch angle control device. A connecting passage that connects the accumulator and the tank, a discharge valve that is provided in the middle of the connecting passage and that opens when receiving a valve opening force, and is attached to a radially inner end of the wind turbine blade. The wind turbine blade pitch angle control device according to any one of claims 1 to 3, further comprising a valve-opening cam that applies a valve-opening force to the discharge valve when the blade rotates just before the feathering state. 4. The pitch angle control device for wind turbine blades according to claim 3, wherein the control motor and the emergency fluid motor are arranged on the opposite side surfaces of the housing accommodating the conversion moving means and the mechanical transmission means while maintaining a coaxial relationship.

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