JP2008106700A - Wind power generating device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a gyro-mill type wind power generating device equipped with a self-starting mechanism capable of enhancing power generating capacity by harnessing omnidirectionality to wind, which is an advantage of a gyro-mill type, and by controlling revolution of a windmill to make the most of windmill efficiency. <P>SOLUTION: The wind power generating device using a gyro-mill type windmill is provided with the self-starting mechanism composed of a wind velocity sensor, a controller to send a starting signal to a driver when set wind velocity is detected, a geared motor rotating/starting a windmill shaft through a driving gear with the starting signal from the driver, and a control means for stopping the driving gear when the number of revolution of the windmill is increased up to a set value and idling the windmill shaft through an idle clutch. A load is controlled so that a peripheral speed ratio of a windmill blade can become 2-3 to generate power. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a gyromill type wind power generator provided with a self-starting mechanism for starting a windmill from a low wind speed range.

In recent years, large-scale power generators of 1500 to 2000 kW class are becoming mainstream with the background of fossil fuel depletion, CO ₂ emission suppression, and global environment conservation. However, large power generators have problems such as location restrictions and power transmission facilities, and in order to further spread wind power generation, it is highly efficient and quiet that can be installed on the rooftops, urban areas, and residential areas of urban buildings. A small power generator (500 to 3000 W class) is indispensable.

  On the other hand, the types of wind turbines for wind power generators are roughly classified into horizontal axis wind turbines typified by a propeller type and vertical axis wind turbines typified by a gyromill type. In general, propeller type windmills are developed in Western countries where wind energy conversion efficiency is good and the wind direction does not change so much. In large windmills, two or three wings are adopted. Propeller type windmills have the advantage of good wind energy conversion efficiency, but because the rotating surface must face the wind direction, direction control is necessary, and the tracking performance is inferior when the wind direction changes There are drawbacks. Further, a slip ring or the like is required for taking out the power and signal system, and there is a problem that the number of consumable parts increases.

  The wind blown to urban areas and urban areas in Japan is weaker than the wind blown to mountainous areas and coastlines, and the wind speed and direction change frequently. Therefore, vertical axis windmills (gyromill type windmills) that can take in wind energy from anywhere are used. Is suitable.

  However, the gyromill type windmill has the disadvantages of poor startability and poor power generation efficiency at low speeds.

  Conventionally, in a small wind power generator, various proposals have been made in order to improve the startability and improve the operating rate of wind power generation regardless of a horizontal axis wind turbine or a vertical axis wind turbine.

  For example, in the case of a propeller type windmill, it is started by canceling the cogging torque of the generator, or by connecting a starter motor to the windmill shaft and actively giving a rotational force to start, and when it reaches a predetermined rotation after the start Techniques for separating a motor for a motor from a windmill have been proposed (see, for example, Patent Documents 1 and 2).

  However, the techniques of Patent Documents 1 and 2 require a relatively large current supply. For example, in a situation where the windless state continues for a long time, it is necessary to supply the motor driving current for a long time, and a large amount of power energy is consumed. Therefore, in the above-described conventional technology, there arises a problem that it is difficult to adapt to actual use of the small-capacity wind power generator.

As a technique for improving the techniques of Patent Documents 1 and 2, Patent Document 3 proposes a system that saves power by turning on and off the current supply system for startup assist depending on the rotation state of the windmill.
Japanese Utility Model Publication No. 6-9400 JP-A-8-322298 JP 2004-285991 A

  The above-described prior art is mainly intended to reduce the power consumption at the time of starting the windmill, and is not practically sufficient in terms of improving the operating efficiency of the windmill comprehensively. .

  The present invention makes use of the omnidirectionality with respect to the wind, which is an advantage of the gyromill type, and also includes a self-starting mechanism capable of increasing the power generation capacity by utilizing the windmill efficiency to the maximum by controlling the windmill rotation. The purpose is to provide a mill-type wind turbine generator.

  The present invention relates to a wind power generator using a gyromill type windmill, a wind speed sensor, a controller for sending a start signal to a driver when a set wind speed is detected, and a windmill shaft via a drive gear by a start signal from the driver. A self-starting mechanism comprising a motor with a speed reducer for starting rotation of the wind turbine and a control means for stopping the drive gear when the wind turbine rotation speed rises to a set value and causing the wind turbine shaft to idle via the idle clutch. This is a gyromill type wind power generator that generates electric power by controlling a load so that a peripheral speed ratio is 2 to 3.

  Hereinafter, the present invention will be described in detail. In general gyromill type windmills, the windmill begins to rotate at a startup wind speed of 2 to 5 m / s. However, if the wind becomes weaker or fluctuates below the startup wind speed, power generation may not occur and the windmill rotation may also stop. . As mentioned above, in order to improve the startability of the windmill, a method of canceling the cogging torque of the generator has been proposed, but it is obvious that power generation is not possible simply by starting up, and the operating rate of the windmill does not increase It is.

  The present inventors conducted a thorough experiment on the wind speed rotation characteristics of the gyromill type windmill. FIG. 1 is a graph showing the relationship between wind speed and wind turbine rotation speed in a wind tunnel experiment on an actual machine scale.

  It can be seen that when the wind speed is increased from no wind, the startup wind speed is about 4 m / s, and when the wind speed exceeds 8 m / s, the rotational speed increases rapidly. On the other hand, as can be seen at a glance in FIG. 1, there is a large hysteresis in the acceleration direction and deceleration direction of the windmill, and the startup wind speed from no wind is about 4 m / s, whereas in the deceleration direction at the same wind speed. The rotation speed is about 80 rpm. Furthermore, the rotation of 60 rpm is maintained even at a wind speed of 3.5 m / s, and almost perfect linear characteristics are shown up to the maximum rotation of 360 rpm.

  This means that once the windmill reaches a certain rotation, it reacts linearly to the wind speed. Conversely, even if a middle wind (5-8 m / s) blows, it is difficult to rotate in a stopped windmill, It means that it will not rise easily.

  The present invention has been made on the basis of such knowledge, and increases the power generation capacity by utilizing the wind turbine efficiency to the maximum by controlling the rotation of the gyromill type wind turbine.

  This will be described in more detail with reference to the graph of FIG. 2 which is a schematic representation of the graph of FIG. In FIG. 2, A is a point indicating the startup wind speed, and B is a point indicating the efficiency maintaining minimum rotational speed. If there is no self-start, the windmill starts from point A, but if there is no significant increase in wind speed, it cannot move to the BC curve (efficiency maintenance curve) via A ', and the windmill rotates with low efficiency. It will be to the extent that it is. The cause of this is thought to be due to the shape, number of blades, inertial force, and other mechanical sliding resistance. More or less, this hysteresis is a characteristic of a gyromill type windmill.

  The B-C curve is a rotational state that maintains the maximum wind turbine efficiency, and both C to B (down) and B to C (up) are reversible, and does not shift from A 'to A when descending.

  A feature of the gyromill type wind power generator of the present invention is that point A (minimum efficiency maintenance) is detected when the minimum wind speed at which the wind turbine can generate power is detected by omitting the AA ′ curve (startability, low-speed wind turbine efficiency poor state). It is to have a mechanism (self-starting mechanism) that can increase the number of revolutions up to (number of revolutions).

  This point B is determined by the peripheral speed ratio 2-3 of the windmill blade. For example, when the windmill diameter is 2 m, the cut-in wind speed (minimum wind speed capable of generating power) is 3 m / s, and the peripheral speed ratio is 2, the point B is 57 rpm, and the driving force from the start up to 57 rpm is consumed as electric power, but acceleration Since the time is a short time of several tens of seconds and the set speed of the windmill is low, a small motor with a reduction gear can be used and power consumption is low.

  The gyromill type wind power generator according to the present invention includes a wind speed sensor, a controller that sends a start signal to a driver when a set wind speed is detected, and a deceleration that rotates the windmill shaft via a drive gear by the start signal from the driver. It is an essential component to have a self-starting mechanism comprising a motor with a motor and a control means for stopping the drive gear when the wind turbine rotation speed rises to a set value and causing the wind turbine shaft to idle via the idle clutch. FIG. 3 shows an overall view of an example of the apparatus, FIG. 4 shows details of the gear box, and FIG. 5 shows a system configuration diagram.

  In FIG. 3, 1 is a main blade, 2 is a support arm, 3 is a rotor shaft, 4 is a gear box, 5 is a wind speed sensor, 6 is a solar panel to be installed if desired, and 7 is a control box with a built-in control system. , 8 are struts, and the basic configuration may be the same as that of a conventional gyromill type wind turbine.

  In FIG. 4, 9 is a drive gear, 10 is an idle clutch, and 11 is a shaft.

  When there is no wind, naturally the windmill rotation is zero. When the wind speed sensor detects a slight wind with a wind speed of 2 to 3 m / s, the controller sends a start signal to the driver and starts rotating the windmill shaft via the drive gear by the motor with a speed reducer.

  The driver operates the motor with a speed reducer for a few dozen seconds from the state where the windmill is stopped until reaching a certain set speed, and when the speed of the windmill rises to the set value, the speed reducer receives a stop signal from the control means. Stop the attached motor. Since the motor with a reduction gear is operated by converting the frequency from 0 Hz to a set number of rotations and several tens of Hz when starting from the driver, there is no impact due to the wind turbine inertia force, and there is no power consumption due to the inrush current. For example, in a 1000 W class windmill, the operation time is 20 seconds, the electric speed reducer current is about 0.5 A, and the power consumption is small.

  When the motor with a reduction gear is stopped, the drive gear is stopped, but the wind turbine shaft is idled via an idle clutch. Since the idling resistance at this time is as small as the bearing resistance, the wind turbine energy effectively drives the generator nearly 100%.

  The wind turbine set rotational speed is increased to the minimum rotational speed for maintaining the optimum wind turbine efficiency, and then the driving force is disconnected. The wind turbine can maintain its rotation even if a wind of about 2 m / s comes as a fluctuating wind, if only the friction loss of the mechanical system is extracted from the wind as fluid energy by the rotational energy given in the initial stage. Furthermore, if the wind speed increases, the wind turbine rotation speed increases linearly and increases to the maximum rotation speed of the wind speed. If a power generation load is applied in this state, the wind turbine rotation starts to decrease, and if the load is too large, it decreases past the maximum wind turbine efficiency point, but by controlling the load on and off in a timely manner, the maximum efficiency rotation speed of the wind turbine can be reduced. Can be maintained. Furthermore, since the rotational energy (inertial force) of the windmill can be effectively used for power generation from the maximum no-load rotational speed of the windmill to the power generation maintaining rotational speed, the windmill efficiency is improved.

  The appropriate windmill setting rotational speed can be determined from the peripheral speed ratio of the windmill blade. When the peripheral speed ratio λ, the wind speed v, the windmill rotational diameter D, and the windmill rotational speed N are represented, λ = πDN / v. In the wind turbine rotation control according to the present invention, the wind speed and the wind turbine rotation speed are always sensed from a slight wind speed to a high wind speed, and the load is controlled so that the peripheral speed ratio λ = 2 to 3 that is the maximum wind turbine efficiency is obtained. Is to secure. When the wind speed is strong and the maximum speed exceeds the peripheral speed ratio λ = 3-4, the machine brake is stopped for safety.

  The wind speed sensor used in the present invention preferably employs a transmission / reception type ultrasonic sensor. It is small and lightweight, is not affected by temperature, and has no rotating parts. Therefore, it is suitable for wind turbine measurement with a long life and stable wind speed and direction.

  In general gyromill type windmills, it is necessary to reduce the weight of windmill blades in order to improve startability, and materials such as FRP and carbon fiber are selected. However, it takes time to manufacture, and there are problems in terms of adhesive strength and price. there were. Since the self-starting wind turbine blade of the present invention is forcibly started, it is not necessary to reduce the weight significantly, and high-strength aluminum, iron-based, titanium, or other metal elastic material can be used, and the weight of the blade uses inertial force. This is advantageous for the wind turbine control of the invention, and it is easy to cope with the increase in the size of the wind turbine. In addition, the manufacturing method can be general molding processing such as extrusion molding and press molding, and the manufacturing cost can be reduced and a large amount can be supplied with a short delivery time.

  FIG. 5 shows a case where an independent power source battery load is connected to a wind turbine as an embodiment. The switch is usually installed for the purpose of switching to an emergency power source when using battery power and during a commercial external power failure.

FIG. 1 is a graph showing the relationship between wind speed and wind turbine rotation speed in a wind tunnel experiment on an actual machine scale. FIG. 2 is a graph schematically showing the graph of FIG. FIG. 3 is an overall view of an example of the gyromill type wind power generator of the present invention. FIG. 4 is a diagram showing details of the gear box. FIG. 5 is a diagram showing an example of a system configuration used in the apparatus of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Main blade 2 Support arm 3 Rotor shaft 4 Gear box 5 Wind speed sensor 6 Photovoltaic panel 7 Control box 8 Strut 9 Drive gear 10 Idling clutch 11 Shaft

Claims (1)

In a wind turbine generator using a gyromill type windmill, a wind speed sensor, a controller that sends a start signal to a driver when a set wind speed is detected, and a windmill shaft that starts rotation via a drive gear by the start signal from the driver It has a self-starting mechanism that consists of a motor with a speed reducer and a control means that stops the drive gear when the wind turbine rotation speed rises to the set value and idles the wind turbine shaft via the idle clutch, and the peripheral speed ratio of the wind turbine blade is A gyromill type wind power generator that generates power by controlling a load so that it becomes 2-3.

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