JP5404367B2 - Wind generator braking system - Google Patents

Description

  The present invention relates to a wind power generator braking device that stops a wind power generator in a strong wind or the like, and more particularly to a wind power generator braking device that stops a wind turbine by electromagnetic force.

  In recent years, wind power, which is a renewable energy, has attracted attention and is spreading due to problems such as global warming and resource reduction. Wind power generation includes so-called wind power generation. Wind power generation is a method in which wind power is converted into electric power by combining a windmill and a generator, and the obtained electric power is converted into a form suitable for the intended use. This method has the advantage of a wide range of applications, and has become the current mainstream.

  Some wind power generators are configured to stop the wind turbine by an electromagnetic braking device when the rotational speed of the wind turbine and the generator is excessively increased due to excessive wind speed such as storm. Such an electromagnetic braking device detects, for example, the rotational speed of a generator, and when the detected rotational speed exceeds a certain value, the circuit of the generator is short-circuited, and the rotational load is increased by the electric power generated at that time. Some of them reduce the rotation of the generator and stop it. As a braking device using such an electromagnetic braking device, for example, the one disclosed in Patent Document 1 is known.

JP 2002-339856 A (0008, 0015)

  By the way, when it is going to stop a windmill by excessive wind speed, it is necessary to stop a windmill as short as possible. This means that the power generated by the generator during braking needs to be released in the shortest possible time. As a solution to this problem, for example, there is a technique of lowering the thermal resistance of means for consuming electric power generated during braking (power consumption means) and using an element having a large power capacity as the power consumption means.

  However, the use of such means increases the capacity and size of the power consuming means, and it is necessary to consume power by the power consuming means from the start of braking until the wind turbine stops. The amount of heat generated by the power consuming means is increased. As a result, the braking device is increased in size and the amount of heat generated by the power consuming means is large, so that the arrangement of the devices constituting the braking device may be restricted. The present invention has been made in view of the above, and in a braking device for a wind power generator that stops a windmill by causing the power consuming means to consume the power generated by the generator, the power consuming means is downsized. With the goal.

  In order to solve the above-described problems and achieve the object, the present invention stores an electric energy generated by a generator that converts wind power into electric energy, and discharges the stored electric energy, and the electric storage means Power consumption means for consuming electrical energy stored in the power supply, and switching means for electrically connecting or disconnecting the generator and the power storage means based on wind speed information indicating the speed of the wind driving the generator. , A braking device for wind power generators.

  In the present invention, when braking the wind power generator, the switching means changes the supply destination of the electric energy generated by the generator of the wind power generator to the power storage means, and the power storage means temporarily stores the electric energy. And after a generator and a windmill stop, the electrical energy stored in the electrical storage means is consumed by an electric power consumption means. Thus, the timing at which the power consuming means consumes the electric energy generated by the braking of the wind power generator can be set later than when the wind power generator is braked. In addition, since the power storage means can control the discharge time according to the specifications of the power consuming means connected to the power storage means, the electric energy generated by braking of the wind power generator and stored in the power storage means is the time required for power storage. Can be discharged in a longer time. By these actions, the present invention can greatly reduce the power consumption means.

  As a desirable aspect of the present invention, the generator has a short-circuit means for short-circuiting the output of the generator, and the switching means recognizes that the generator has stopped after electrically connecting the generator and the power storage means. In this case, it is preferable that the switching means electrically cuts off the generator and the power storage means, and the short-circuit means short-circuits the output of the generator. By this short-circuit means short-circuiting the generator circuit, the generator can be reliably stopped even while the power consuming means is consuming the electrical energy stored in the power storage means.

  As a desirable aspect of the present invention, it is preferable to have an intermittent means for electrically connecting or disconnecting the power storage means and the power consumption means between the power storage means and the power consumption means. During braking, while the electrical energy generated by the generator is stored in the power storage means, the electrical energy generated by the generator is converted into the power consumption means by electrically disconnecting the power storage device and the power consumption means by the intermittent means. It does n’t flow. Therefore, assuming that a part of the electric energy generated by the generator flows to the power consuming means, it is not necessary to set the power capacity of the power consuming means large, so the power consuming means can be further reduced in size. .

  As a desirable aspect of the present invention, the intermittent means includes the power storage means, while the switching means electrically connects the power generator and the power storage means, and it is not recognized that the power generator has stopped. It is preferable that the power storage means and the power consumption means are electrically connected after the power consumption means is electrically cut off and it is recognized that the generator has stopped. Thus, during braking of the wind power generator, electrical energy does not flow to the power consuming means, and when the power storage means is discharged, the stored electrical energy can be reliably consumed by the power consuming means.

  As a desirable mode of the present invention, it is preferable that the intermittent means and the power consuming means are constituted by semiconductor switching elements. As a result, the apparatus configuration can be simplified and the number of parts can be reduced.

  As a desirable aspect of the present invention, it is preferable that a voltage drop means is provided between the generator and the power storage means. The output voltage of the generator is 100 V to 200 V, and there is a possibility that the power storage means that can directly apply this is limited. In this aspect, since the voltage drop means is provided and the output voltage of the generator is stepped down and applied to the power storage device, the degree of freedom of elements constituting the power storage device and the combination thereof is increased.

  As a desirable mode of the present invention, it is preferable to have a rectifying means between the voltage drop means and the power storage means. Accordingly, since direct current power can be applied to the power storage means, the degree of freedom in designing the power storage means is improved.

  As a desirable mode of the present invention, it is preferable that the switching unit is configured by combining a plurality of semiconductor switching elements, and electric energy generated by the generator is converted into DC power and input to the switching unit. . Thus, for example, an inverter circuit can be configured by a plurality of semiconductor switching elements to serve as switching means. In this way, with one switching means, power is stored in the power storage means during braking of the wind power generator, and when the power consumption means consumes the electrical energy stored in the power storage means, the generator and the windmill are stopped. Both can be realized.

  As a desirable mode of the present invention, it is preferable that the switching means electrically connects the generator and the power storage means when the wind speed information is equal to or higher than a predetermined threshold value.

  The present invention can reduce the size of the power consuming means in the braking device for a wind power generator that stops the windmill by consuming the power generated by the generator to the power consuming means.

FIG. 1 is a schematic diagram illustrating a configuration of a braking device for wind power generators according to a first embodiment. FIG. 2 is a flowchart for explaining the operation of the braking device according to the present embodiment. FIG. 3 is a timing chart when the braking device according to this embodiment operates. FIG. 4 is a schematic diagram illustrating a configuration of a braking device according to a modification of the present embodiment. FIG. 5 is a schematic diagram illustrating a configuration of a braking device according to the second embodiment. FIG. 6 is a schematic diagram illustrating the configuration of the braking device according to the second embodiment. FIG. 7 is a timing chart when the braking device according to the second embodiment operates. FIG. 8 is a schematic diagram illustrating the configuration of the braking device according to the third embodiment. FIG. 9 is a diagram illustrating an example in which an interrupter is provided in a configuration that does not use a transformer. FIG. 10 is a timing chart when the braking apparatus according to the third embodiment operates. FIG. 11 is a diagram illustrating an example in which the interrupter and the power consuming device are configured by semiconductor switching elements. FIG. 12 is a schematic diagram illustrating a configuration of a braking device according to a modification of the third embodiment. FIG. 13 is a schematic diagram illustrating a configuration of a braking device according to the fourth embodiment. FIG. 14 is a schematic diagram illustrating a configuration of a braking device according to a modification of the fourth embodiment. FIG. 15 is a timing chart when the braking device according to the fourth embodiment operates.

  Hereinafter, the present invention will be described in detail with reference to the drawings. The present invention is not limited by the following modes for carrying out the invention (hereinafter referred to as embodiments). In addition, constituent elements in the following embodiments include those that can be easily assumed by those skilled in the art, those that are substantially the same, and those in a so-called equivalent range. Furthermore, the constituent elements disclosed in the following embodiments can be appropriately combined.

(Embodiment 1)
FIG. 1 is a schematic diagram illustrating a configuration of a braking device for wind power generators according to a first embodiment. A wind power generator braking device (hereinafter referred to as a braking device if necessary) 10 is incorporated in the wind power generator 1. The wind power generator 1 includes a power generator 2, a windmill 3 attached to the input shaft 4 of the power generator 2, and a braking device 10. When the windmill 3 receives wind, the windmill 3 rotates. The rotational force of the windmill 3 is input to the generator 2 via the input shaft 4 to drive it. Thereby, the generator 2 generates electrical energy. Thus, the generator 2 is an energy conversion device that converts wind power into electrical energy. The electrical energy generated by the generator 2 is input to the converter 5 that is a power conversion device via the braking device 10. The converter 5 converts the electrical energy generated by the generator 2 and outputs it to a power consumption target 6 such as a home appliance.

  In the present embodiment, the braking device 10 is disposed between the generator 2 and the converter 5. The braking device 10 has input terminals Tia and Tib and output terminals Toa and Tob, and the output terminal of the generator 2 is connected to the input terminals Tia and Tib. Further, the input terminal of the converter 5 is connected to the output terminals Toa and Tob of the braking device 10. The braking device 10 shorts the output of the generator 2 by short-circuiting the armature circuit of the generator 2, and stops the generator 2 while increasing the rotational load of the generator 2 by the power generated by the generator 2. Thus, the wind turbine 3 is stopped. Thus, the braking device 10 exhibits a function as a so-called electromagnetic braking device. Note that the stop of the wind power generator 1, the stop of the power generator 2, and the stop of the wind turbine 3 are all used with the same meaning. Next, the configuration of the braking device 10 will be described.

  The braking device 10 includes a power storage device 11 that is a power storage unit, a power consumption device 12 that is a power consumption unit, and a switching device 13 that is a switching unit. Furthermore, in this embodiment, the braking device 10 includes a voltmeter 14 that is a wind speed information detection unit and a control device 15 that is a control unit. The power storage device 11 stores the electrical energy generated by the generator 2 and releases the stored electrical energy. For example, a capacitor, an electric double layer capacitor, or a storage battery (for example, a lead storage battery, a lithium-ion battery, or a nickel-hydrogen battery) can be used for the power storage device 11. The power storage device 11 converts the kinetic energy stored in the flywheel into electric energy by using the electric motor as a generator after rotating the flywheel with an electric motor to convert the electric energy into kinetic energy. May be.

  In the present embodiment, for example, a capacitor is used as the power storage device 11. In this case, the power storage device 11 is connected in parallel to the circuit of the generator 2. In the example shown in FIG. 1, one terminal of the power storage device 11 is electrically connected to the input terminal Tib of the braking device 10, and the other terminal is electrically connected to the input terminal Tia of the braking device 10 via the switching device 13. Connected to.

  The power consuming device 12 consumes electrical energy stored in the power storage device 11. An example of the power consuming device 12 is a resistor. The power consuming device 12 is not limited to a resistor as long as it can consume electric energy, and may be, for example, an electric motor, a lighting device, a magnetic generator, or the like. In this embodiment, a resistor is used for the power consuming device 12. In this case, one terminal of the power consuming device 12 is electrically connected to one terminal of the power storage device 11, and the other terminal of the power consuming device 12 is electrically connected to the other terminal of the power storage device 11. As a result, the power consuming device 12 and the power storage device 11 form a closed circuit.

  The switching device 13 electrically connects or disconnects the generator 2 and the power storage device 11 on the basis of wind speed information indicating the speed of the wind that drives the generator 2 via the windmill 3. A relay, a semiconductor switching element, or the like can be used. In the present embodiment, a switch is used as the switching device 13. When the switching device 13 electrically connects the power generator 2 and the power storage device 11, the power generator 2 and the power storage device 11 form a closed circuit.

  In the present embodiment, the control device 15 controls the operation of the switching device 13. Specifically, the control device 15 electrically connects the generator 2 and the power storage device 11 by closing the switching device 13, that is, electrically connecting the same. Thereby, the supply destination of the electrical energy generated by the generator 2 is the power storage device 11. In addition, the control device 15 opens the switching device 13, that is, electrically cuts off the generator 2 and the power storage device 11. Thereby, the supply destination of the electric energy generated by the generator 2 is the output terminals Toa and Tob of the braking device 10, more specifically, the converter 5. As described above, the switching device 13 switches the supply destination of the electric energy generated by the generator 2 to one of the output terminals Toa and Tob of the power consuming device 12 or the braking device 10.

  The control device 15 is electrically connected to a voltmeter 14 that detects a voltage (generator output voltage) between output terminals of the generator 2, and an output of the voltmeter 14 is input to the control device 15. The control device 15 is configured by, for example, a so-called microcomputer including a processing unit 15P and a storage unit 15M. And the process part 15P reads the computer program for the brake control of the wind power generator 1 from the memory | storage part 15M, executes this, and brakes the wind power generator 1. FIG.

  In the present embodiment, the braking device 10 brakes the wind power generator 1 during a strong wind, thereby stopping the generator 2 and stopping the wind turbine 3. As a result, the braking device 10 avoids over-rotation of the windmill 3 and prevents power exceeding the allowable input from being input to the converter 5 to which power generated by the generator 2 is input. Whether to brake the wind power generator 1 and stop the power generator 2 and the wind turbine 3 is determined based on the wind speed (wind speed) received by the wind turbine 3.

  The generator output voltage is substantially proportional to the rotational speed (rotational angular speed, rotational speed) of the generator 2, and the rotational speed of the generator 2 is proportional to the wind speed. Therefore, in this embodiment, the generator output voltage detected by the voltmeter 14 is used as wind speed information indicating the wind speed for driving the generator 2. The control device 15 acquires the generator output voltage detected by the voltmeter 14, and brakes the wind power generator 1 or releases the braking based on this.

  In the present embodiment, the voltmeter 14 is used as the wind speed information detecting means, but the wind speed information detecting means is not limited to this. For example, a tachometer 16A that detects the rotation speed of the windmill 3 of the wind power generator 1 (that is, the rotation speed of the generator 2) or an anemometer 16B that detects the wind speed may be used as the wind speed information detection means. Therefore, the wind speed information is not limited to the generator output voltage, and the rotational speed and wind speed of the windmill 3 may be used as the wind speed information.

  Since the voltmeter 14 and the tachometer 16A do not have a movable part, there is an advantage that labor and maintenance are relatively reduced. However, since the voltmeter 14 and the tachometer 16A are not intended for measuring the wind speed, they may not be appropriate when information on the wind speed itself is required. On the other hand, since the anemometer 16B is intended to measure the wind speed, the anemometer 16B is preferably used when it is desired to use the wind speed detected by the anemometer 16B for purposes other than the braking purpose of the wind power generator 1.

  When the braking device 10 brakes the wind power generator 1, the control device 15 electrically connects the generator 2 and the power storage device 11 by closing the switching device 13. As a result, the electric energy generated by the generator 2 is stored in the power storage device 11, thereby increasing the rotational load of the generator 2, so that the wind generator 1 and the generator 2 are stopped, that is, the windmill 3 is stopped. The electrical energy released when the windmill 3 stops is substantially equal to the sum of the rotational energy of the windmill 3 when braking is started and the wind energy generated until the windmill 3 stops. Since the braking device 10 needs to store the electrical energy released when the windmill 3 stops in the power storage device 11, the power storage device 11 stores all the electrical energy released when the wind power generator 1 stops. The capacity is set as much as possible.

  Since the power storage device 11 and the power consumption device 12 form a closed circuit, when the switching device 13 is opened after the electrical energy is stored in the power storage device 11, the electrical energy is discharged from the power storage device 11 and the power consumption device. 12 is consumed here. In the present embodiment, since a resistor is used for the power consuming device 12, the electric energy consumed by the power consuming device 12 is released as heat, for example, into the air (or liquid). After the wind power generator 1 is stopped, the control device 15 opens the switching device 13 at a timing when the power storage device 11 starts discharging, so that the electric energy discharged from the power storage device 11 flows to the power consuming device 12 and is consumed. The

  The braking device 10 temporarily stores the electric energy generated by the generator 2 in the power storage device 11 from the start of braking of the wind power generator 1 until the wind turbine 3 stops, and stores the electric energy after the wind turbine 3 stops. The electric energy stored in the device 11 is consumed by the power consuming device 12. Thereby, the timing at which the electric energy generated by the braking of the wind power generator 1 is consumed by the power consuming device 12 can be set later than when the wind power generator 1 is braked.

  Further, the power storage device 11 can control the discharge time according to the specifications of the resistor connected thereto, the power consuming device 12, and the like. For this reason, the braking device 10 can discharge the electric energy generated by the braking of the wind power generator 1 in the power storage device 11 and then discharge it in a longer time than the time required for power storage. As a result, it is possible to use a power consuming means having a small power capacity as compared with the case where the electric energy generated by the braking of the wind power generator 1 is consumed by the power consuming means such as a resistor at the time of braking. As a result, the power consumption means can be reduced in size.

  For example, when the output of the wind power generator 1 is 1 kw at a wind speed of 12 m / s, power consumption means having a power capacity of about 500 W is used to stop the windmill 3 within 10 seconds by consuming electric power simultaneously with braking. is necessary. However, according to the braking device 10, for example, when the electric energy stored in the power storage device 11 is discharged in 100 seconds, the power capacity of the power consuming device 12 may be about 50 W. Note that the power capacity of the power consuming device 12 can be further reduced by further increasing the discharge time. As described above, when the braking device 10 is used, the power capacity of the power consuming device 12 can be significantly reduced as compared with the case where power is consumed simultaneously with braking. Can be realized.

  Further, the power consumption device 12 consumes less power per unit time than when power is consumed simultaneously with braking. For this reason, compared with the case where the power consuming apparatus 12 consumes electric power at the same time as braking, the heat dissipation amount per unit time is also reduced, so that the influence of heat generated by the power consuming apparatus 12 can be reduced. As a result, the power consuming device 12 and the devices constituting the braking device 10 can be disposed close to each other, and the braking device 10 can be configured compactly. In addition, the power consuming device 12 also has a small heat dissipation amount per unit time, so that it can be easily cooled.

  When the power consuming device 12 is cooled, the power consuming device 12 is composed of a resistor and a blower, and the electric energy discharged from the power storage device 11 is consumed by heating the resistor and driving the blower. May be supplied to the resistor to cool it. In this way, it is not necessary to separately provide a cooling means for the power consuming device 12.

  In the present embodiment, the braking device 10 has one set (braking circuit) of the power storage device 11, the power consuming device 12, and the switching device 13, but may have two or more braking circuits. During the discharge of the power storage device 11, the electric energy generated by the generator 2 cannot be stored in the power storage device 11, and as a result, the wind power generator 1 cannot be braked. However, by providing two or more sets of braking circuits in the braking device 10, when the power storage device 11 of a set of braking circuits is discharging, the wind generator 1 is braked using another braking circuit. be able to. This process is executed by the control device 15. In this way, even when it is necessary to brake the wind power generator 1 during the discharge of the power storage device 11, it is possible to cope with it. Next, the operation of the braking device 10 will be described. The operation of the braking device 10 described next is also common in principle in the following modified examples and embodiments.

  FIG. 2 is a flowchart for explaining the operation of the braking device according to the present embodiment. FIG. 3 is a timing chart when the braking device according to this embodiment operates. During the period in which the wind power generator 1 is operating, the braking device 10 monitors whether or not wind exceeding the limit in operation of the wind power generator 1 is blowing (step S101). In this monitoring, the control device 15 of the braking device 10 acquires the generator output voltage Eg from the voltmeter 14 at a predetermined cycle.

  Next, the control device 15 compares the generator output voltage Eg acquired from the voltmeter 14 with a predetermined threshold value (braking start voltage) Egc (step S102). The braking start voltage Egc is a voltage output from the generator 2 of the wind power generator 1 at a restricted wind speed in the operation of the wind power generator 1, and is set based on the specifications of the wind power generator 1 and the converter 5.

  As a result of comparing the generator output voltage Eg and the braking start voltage Egc, when the control device 15 determines that Eg ≧ Egc (Yes in step S102), there is a wind that exceeds the operating limit of the wind power generator 1. It can be judged that it is blowing. In this case, since it is necessary to brake the wind power generator 1 to stop the power generator 2, that is, the wind turbine 3, the braking device 10 starts braking the wind power generator 1 (step S103). In the timing chart shown in FIG. 3, Eg ≧ Egc when t = t1. When the braking device 10 brakes the wind power generator 1, the control device 15 electrically connects the generator 2 and the power storage device 11 by closing the switching device 13. 3 indicates the operation of the switching device 13, and at t = t1, the switching device 13 is ON, that is, closed.

  Then, the electrical energy generated by the generator 2 is stored in the power storage device 11. As a result, the inter-terminal voltage Ec of the power storage device 11 increases with time (after t = t1 in FIG. 3). On the other hand, when the braking of the wind power generator 1 is started (after t = t1), the generator output voltage Eg decreases with time. This is because, in the braking operation of the braking device 10, as a result of the electrical storage device 11 storing the electrical energy generated by the generator 2, the rotational load of the generator 2 increases and the generator 2, that is, the windmill 3 rotates. It means that the speed is decreasing.

  When the switching device 13 is closed, the power storage device 11 and the power consuming device 12 are connected to the generator 2 in parallel. For this reason, when the amount of power stored in the power storage device 11 increases and the magnitude relationship between the impedances of both changes, a part of the electrical energy generated by the generator 2 is consumed by the power consuming device 12. As a result, as shown in FIG. 3, the power consumption P of the power consuming device 12 rises with time after the switching device 13 is closed (after t = t1).

  When braking of the wind power generator 1 is started, the control device 15 determines whether or not it is recognized that the power generator 2, that is, the windmill 3 is stopped (step S104). In the present embodiment, whether or not the generator 2 is recognized as being stopped is determined by whether or not the generator output voltage Eg is equal to or lower than the stop threshold Eg0. The stop threshold value Eg0 is a value used to determine whether or not the generator 2 is recognized to have stopped.

  When the rotational speed of the generator 2 decreases, the generator output voltage Eg also decreases. When the generator 2 stops, the generator output voltage Eg becomes zero. Here, even if the generator 2 is not completely stopped, it may be recognized that the generator 2 has stopped as long as the rotational speed is such that the generator 2 is stopped. In the present embodiment, the stop threshold Eg0 is set to a value equal to or lower than the voltage output by the generator 2 when it is recognized that the generator 2 has stopped. Accordingly, the stop threshold Eg0 may be 0, that is, the generator output voltage Eg when the generator 2 is completely stopped.

  When the control device 15 determines that Eg> Egc (No in step S104), it is recognized that the generator 2 has not stopped, so the process returns to step S103, and the control device 15 continues to brake the wind power generator 1. To do. That is, the control device 15 maintains the switching device 13 in a closed state. When the control device 15 determines that Eg ≦ Egc (step S104, Yes), it is recognized that the generator 2 has stopped (t = t2 in FIG. 3). In this case, as shown in FIG. 3, the inter-terminal voltage Ec of the power storage device 11 is Ec1, and the power consumption P of the power consuming device 12 is P1.

  If it is recognized that the generator 2 has stopped, the braking device 10 discharges the electrical energy stored in the power storage device 11 (step S105). In this case, the control device 15 turns off the switching device 13, that is, opens it, and electrically shuts off the generator 2 and the power storage device 11 (t = t 2 in FIG. 3). As a result, the electric energy discharged from the power storage device 11 is consumed by the power consuming device 12 and is released into the air as heat. Then, it returns to step S101 and the braking device 10 continues monitoring.

  Next, it returns to step S102 and demonstrates. In step S102, when the control device 15 determines that Eg <Egc (No in step S102), it can be determined that the wind exceeding the limit in operation of the wind power generator 1 is not blowing. In this case, the braking device 10 does not brake the wind power generator 1. And the wind power generator 1 continues an electric power generation (step S106). In this case, it returns to step S101 and the braking device 10 continues monitoring. By such a procedure, the braking device 10 realizes braking of the wind power generator 1. As a result, the braking device 10 can reliably brake the wind power generator 1 and stop the wind turbine 3 when the wind blows beyond the limit in operation of the wind power generator 1.

(Modification)
FIG. 4 is a schematic diagram illustrating a configuration of a braking device according to a modification of the present embodiment. This modified example has substantially the same configuration as that of the first embodiment, except that a voltage drop unit is provided between the generator of the wind power generator and the power storage unit. Other configurations are the same as those of the first embodiment.

  As shown in FIG. 4, the braking device 10 a includes a transformer 17 that is a voltage drop unit. One terminal of the transformer 17 is electrically connected to the input terminal Tib, and the other terminal is electrically connected to one terminal of the switching device 13. The other terminal of the switching device 13 is connected to the input terminal Tia. Thus, the transformer 17 which is a voltage drop means is provided between the input terminals Tia and Tib of the braking device 10a and the power storage device 11. Here, as shown in FIG. 1, the output terminals of the generator 2 provided in the wind power generator 1 are electrically connected to the input terminals Tia and Tib. Therefore, the transformer 17 is provided between the generator 2 and the power storage device 11.

  When the switching device 13 is closed by the control device 15, the electrical energy generated by the generator 2 is input to the power storage device 11 via the transformer 17. Since the transformer 17 steps down the voltage output from the generator 2 and outputs the voltage, a voltage lower than the generator output voltage is applied between the terminals of the power storage device 11 constituting the braking device 10a.

  Thereby, the power storage device 11 can store the power generated by the power generator 2 after reducing the generator output voltage to a voltage suitable for the power storage device 11. Usually, the generator output voltage is about 180V, the charge / discharge voltage of the lithium-ion battery is 3.7V to 4.2V, and the charge / discharge voltage of the electric double layer capacitor is around 2V. Therefore, in the configuration of the braking device 10 shown in FIG. 1, when a lithium-ion battery or an electric double layer capacitor is used for the power storage device 11, it is necessary to connect a large number of cells in series. However, according to this modification, since the generator output voltage is stepped down and then applied to both terminals of the power storage device 11, a lithium-ion battery or an electric double layer capacitor can be used without connecting many cells in series. The power storage device 11 can be used. Thus, since braking device 10a is provided with a voltage drop means, the freedom degree of the element which comprises power storage device 11, and its combination becomes large.

  In this embodiment and its modification, the braking devices 10 and 10a are connected to the output terminals of the generator 2 constituting the wind power generator 1, and the output terminals Toa and Tob of the braking devices 10 and 10a are connected to the input terminals of the converter 5. Connect with. With such a configuration, the wind power generator 1 can be braked by the braking devices 10 and 10a regardless of the specifications of the converter 5. Therefore, even if the converter 5 is for general-purpose products or existing solar power generation and does not have the braking function of the wind power generator 1, it can be connected to the wind power generator 1 via the braking devices 10, 10a. The braking of the wind power generator 1 can be realized only by connecting between the converter 5 and the converter 5. Thus, the braking devices 10 and 10a are particularly effective for braking a relatively small (less than 10 kW) wind power generator for which a dedicated converter cannot be prepared. It is not excluded to apply the braking devices 10 and 10a to a large wind power generator.

  Further, when a dedicated converter is prepared for the wind power generator 1, a braking function based on the principle of the braking devices 10, 10a may be added to the converter. That is, for example, the power storage device 11, the power consuming device 12, and the switching device 13 shown in FIG. 1 are provided between the input terminal and the output terminal of the converter, and the wind generator 1 The generator 2 and the power storage device 11 are electrically connected or disconnected. Even if it does in this way, since the power consumption apparatus 12 can be reduced in size, even when the braking function of the wind power generator 1 is incorporated in a converter, the enlargement of a converter can be suppressed. In addition, when a braking function based on the principle of the braking devices 10 and 10a is added to the converter, a power consumption target such as a home appliance may be used as a power consumption means instead of the power consumption device 12. Further, when the power consuming device 12 is used, when there is no power demand for power consumption such as home appliances, the electric energy stored in the power storage device 11 is consumed by the power consuming device 12, and the power demand is present. May consume the electric energy stored in the power storage device 11 as the power consumption target.

  As described above, in the present embodiment and the modification thereof, when braking the wind power generator, the electric energy generated by the power generator of the wind power generator is temporarily stored in the power storage means, and is stored after the generator and the windmill are stopped. Electric energy is consumed by means of power consumption. Thus, during braking, the power consumption means is compared with the configuration in which the electric energy generated by the generator is consumed by the power consumption means while the generator and the wind turbine are stopped after the braking of the wind power generator is started. Can be greatly reduced in size. The configurations disclosed in the present embodiment and its modifications can be applied as appropriate in the following.

(Embodiment 2)
5 and 6 are schematic views illustrating the configuration of the braking device according to the second embodiment. The second embodiment has substantially the same configuration as that of the first embodiment and its modification, but differs in that it has a short-circuit means for short-circuiting the output of the generator of the wind power generator. Other configurations are the same as those of the first embodiment and the modifications thereof, and the configurations of the above-described embodiments and the modifications thereof can be appropriately combined with the present embodiment.

  As shown in FIG. 5, the braking device 10b includes a short circuit (short circuit means) 18 between the input terminals Tia and Tib. The short circuit 18 has a function of electrically connecting and short-circuiting the output terminal of the generator 2, and disconnecting the electrical connection of the output terminal to release the short circuit. For the short circuit 18, for example, a switch, a relay, a semiconductor switching element, or the like can be used. In the present embodiment, a switch controlled by the control device 15 is used as the short circuit 18.

  In the present embodiment, the short circuit 18 is provided between the switching device 13 and the power storage device 11 and the output terminals Toa and Tob of the braking device 10b, but the input terminals Tia and Tib of the braking device 10b, the switching device 13 and the power storage. You may provide between the apparatuses 11. FIG. The braking device 10c shown in FIG. 6 is obtained by providing a short circuit 18 to the braking device 10a shown in FIG. Next, the operation of the braking devices 10b and 10c will be described.

  FIG. 7 is a timing chart when the braking device according to the second embodiment operates. 7 indicates the operation of the switching device 13, and SWY indicates the operation of the short circuit 18. When the braking devices 10 b and 10 c brake the wind power generator 1, the control device 15 electrically connects the generator 2 and the power storage device 11 by closing the switching device 13. As shown in FIG. 7, at t = t1, the switching device 13 is ON, that is, closed. At this time, the control device 15 turns off the short circuit 18, that is, keeps it open, and does not short the output of the generator 2 of the wind power generator 1.

  When the switching device 13 is closed, the electric energy generated by the generator 2 is stored in the power storage device 11. Thereby, the inter-terminal voltage Ec of the power storage device 11 rises with time (after t = t1 in FIG. 7). On the other hand, when the braking of the wind power generator 1 is started (after t = t1), the generator output voltage Eg decreases with time. This is because in the braking operation of the braking devices 10b and 10c, as a result of the electrical storage device 11 storing the electrical energy generated by the generator 2, the rotational load of the generator 2 increases, and the generator 2, that is, the windmill 3 It means that the rotation speed of is decreasing.

  If the control device 15 determines that Eg ≦ Egc after braking of the wind power generator 1 is started (t = t2 in FIG. 7), it is recognized that the power generator 2, that is, the windmill 3 has stopped. Thus, when it is recognized that the generator 2 has stopped after the switching device 13 electrically connects the generator 2 and the power storage device 11, the braking devices 10 b and 10 c are stored in the power storage device 11. Discharge electrical energy. For this reason, the control device 15 turns off the switching device 13, that is, opens it, electrically shuts off the generator 2 and the power storage device 11, and turns on the shunt 18, that is, closes the power generation device of the wind power generator 1. The output of the machine 2 is short-circuited (t = t2 in FIG. 7).

  As a result, the electric energy discharged from the power storage device 11 is consumed by the power consuming device 12 and is released into the air as heat. At the same time, since the output of the generator 2 of the wind power generator 1 is short-circuited, the state where the generator 2 and the windmill 3 are stopped can be maintained. According to such a procedure, the braking devices 10 b and 10 c brake the wind power generator 1, and also when the power consumption device 12 consumes the electric energy stored in the power storage device 11, the generator 2 and the windmill 3 The stopped state can be maintained. In the example shown in FIG. 7, the short circuit 18 is OFF, that is, opened when t = t3. This is for restarting the power generation of the wind power generator 1.

  As described above, in the present embodiment, after the generator and the wind turbine are stopped, the output of the generator is short-circuited by the short-circuit unit while the electric energy consuming unit consumes the electric energy stored in the power storage unit. Thus, in addition to downsizing of the power consuming means, the generator and the windmill can be reliably stopped while the power consuming means is consuming the electric energy. The configuration disclosed in this embodiment can be applied as appropriate in the following.

(Embodiment 3)
FIG. 8 is a schematic diagram illustrating the configuration of the braking device according to the third embodiment. FIG. 9 is a diagram illustrating an example in which an interrupter is provided in a configuration that does not use a transformer. The present embodiment is substantially the same as the first embodiment and its modification, but has an intermittent means for electrically connecting or disconnecting the power storage means and the power consumption means between the power storage means and the power consumption means. Is different. Other configurations are the same as those of the first embodiment and the modifications thereof, and the configurations of the above-described embodiments and the modifications thereof can be appropriately combined with the present embodiment.

  As illustrated in FIGS. 8 and 9, the braking device 10 d includes an interrupter (interrupting unit) 19 that electrically connects or disconnects both the power storage device 11 and the power consuming device 12. 8 shows an example in which the voltage output from the generator 2 constituting the wind power generator 1 is stepped down by the transformer 17 and applied to the power storage device 11 (a modification of the first embodiment, see FIG. 4). It shows what was provided. FIG. 9 shows an example in which the voltage output from the generator 2 constituting the wind power generator 1 is directly applied to the power storage device 11 without using the transformer 17 (see Embodiment 1, FIG. 1). It shows what was provided. The interrupter 19 can use a switch, a relay, a semiconductor switching element, etc., for example. In the example shown in FIGS. 8 and 9, a switch controlled by the control device 15 is used as the interrupter 19. Next, the operation of the braking device 10d will be described.

  FIG. 10 is a timing chart when the braking apparatus according to the third embodiment operates. Note that SWX in FIG. 10 indicates the operation of the switching device 13, and SWZ indicates the operation of the interrupter 19. When the braking device 10d brakes the wind power generator 1, the control device 15 closes the switching device 13 and electrically connects the power generator 2 of the wind power generator 1 and the power storage device 11 (t = t1 in FIG. 10). ). At this time, the control device 15 turns off the interrupter 19, that is, opens it, and electrically disconnects the power storage device 11 and the power consuming device 12 (t = t 1 in FIG. 10). After the switching device 13 electrically connects the generator 2 of the wind power generator 1 and the power storage device 11, the control device 15 continues this state while it is not recognized that the generator 2 has stopped. That is, while it is determined No in step S104 of FIG. 2, the interrupter 19 is open.

  Then, after it is recognized that the generator 2 has stopped, that is, after Yes in step S104 of FIG. 2, the control device 15 turns on the interrupter 19, that is, closes (t = t2). As a result, the power storage device 11 and the power consumption device 12 are electrically connected by the interrupter 19, and the electrical energy stored in the power storage device 11 is consumed by the power consumption device 12. At the same time, the control device 15 electrically shuts off the generator 2 and the power storage device 11 by turning off, that is, opening the switching device 13. When all the electrical energy stored in the power storage device 11 is consumed by the power consuming device 12, the control device 15 opens the interrupter 19 (t = t3 in FIG. 10) to prepare for the next braking.

  When the switching device 13 is closed, the power storage device 11 and the power consuming device 12 are connected to the generator 2 in parallel. For this reason, when the amount of electricity stored in the power storage device 11 increases and the magnitude relationship between the two impedances changes, a part of the electrical energy generated by the generator 2 flows to the power consuming device 12. While the switching device 13 is closed during braking of the wind power generator 1, the braking device 10 d opens the interrupter 19 to electrically disconnect the power storage device 11 and the power consuming device 12.

  As a result, since the electric energy generated by the generator 2 does not flow to the power consuming device 12, the power consumption P of the power consuming device 12 is equal to that after the switching device 13 is closed (t = t1) as shown in FIG. After that, it will not rise over time. While the switching device 13 is closed (t = t1 to t2), all the electric energy generated by the generator 2 is stored in the power storage device 11. Therefore, assuming that a part of the electric energy generated by the generator 2 flows to the power consuming device 12, it is not necessary to set the power capacity of the power consuming device 12 large. can do.

  FIG. 11 is a diagram illustrating an example in which the interrupter and the power consuming device are configured by semiconductor switching elements. The braking device 10 d steps down the voltage output from the generator 2 constituting the wind power generator 1 by the transformer 17 and applies it to the power storage device 11. For this reason, the output voltage at the time of the electrical storage apparatus 11 discharging is also comparable as the applied voltage at the time of electrical storage. Therefore, the interrupter (interrupting means) 19 and the power consuming device (power consuming means) 12 shown in FIG. 8 can be configured by the semiconductor switching element 20, thereby simplifying the device configuration and reducing the number of parts. . In this case, a semiconductor switching element 20 having a certain amount of ON resistance is used.

  As the semiconductor switching element 20, for example, an IGBT (Insulated Gate Bipolar Transistor) or a GTO (Gate Turn Off thyristor) can be used. In the present embodiment, an IGBT is used for the semiconductor switching element 20. In this case, when the control device 15 shown in FIG. 8 inputs an ON signal to the gate G of the semiconductor switching element 20, a current flows from the collector C to the emitter E. When the electrical energy stored in the power storage device 11 is consumed, the control device 15 turns on the semiconductor switching element 20, whereby the electrical energy stored in the power storage device 11 flows to the semiconductor switching element 20 and is consumed here. The Thus, it is preferable to use the transformer 17 (voltage drop means) because the choice of the power consumption means is expanded.

  FIG. 12 is a schematic diagram illustrating a configuration of a braking device according to a modification of the third embodiment. As in the second embodiment, the braking device 10e further includes a short circuit (short-circuit means) 18 for short-circuiting the output of the generator 2 of the wind power generator 1 in the configuration of the braking device 10d shown in FIG. Yes. According to this modification, the power generator 2 and the windmill 3 can be reliably stopped by closing the short circuit 18 while the power consuming device 12 is consuming the electric energy discharged from the power storage device 11. . For this reason, the short circuit 18 is closed by the control device 15 after the generator 2 and the wind turbine 3 are stopped, but the timing when the control device 15 closes the interrupter 19 is before the short circuit device 18 is closed. It may be later.

  As mentioned above, in this embodiment and its modification, while a switching device is closed at the time of braking of a wind power generator, an interruption means is opened and an electrical storage means and an electric power consumption means are electrically interrupted. As a result, the electrical energy generated by the generator does not flow to the power consuming means. For this reason, assuming that a part of the electric energy generated by the generator flows to the power consuming means, it is not necessary to set the power capacity of the power consuming means large, so the power consuming means can be further downsized. it can. The configurations disclosed in the present embodiment and its modifications can be applied as appropriate in the following.

(Embodiment 4)
FIG. 13 is a schematic diagram illustrating a configuration of a braking device according to the fourth embodiment. The present embodiment is substantially the same as the modification of the first embodiment, but the switching means is an inverter circuit composed of a plurality of semiconductor switching elements, and the electric energy generated by the generator is converted into DC power. The difference is that the signal is input to the inverter circuit. Other configurations are the same as those of the modification of the first embodiment, and the above-described embodiment and the configuration of the modification can be appropriately combined with the present embodiment.

  As shown in FIG. 13, the braking device 10 f includes a rectifying device 21 configured with four diodes. In addition, the structure of the rectifier 21 is not limited to this. The input terminals 21ia and 21ib of the rectifying device 21 are connected to the input terminals Tia and Tib of the braking device 10f, and the output terminals 21oa and 21ob of the rectifying device 21 are connected to the output terminals Toa and Tob of the braking device 10. The rectifying device 21 rectifies (full-wave rectification) the electric energy (AC power) generated by the generator 2 of the wind power generator 1 input from the input terminals Tia and Tib of the braking device 10f into DC power. The rectifier 21 may be provided in the wind power generator 1 so that the wind power generator 1 outputs DC power. In this case, the braking device 10 f is configured without the rectifying device 21.

  Between the input terminals 21ia and 21ib of the rectifier 21, an inverter circuit 13I composed of a plurality of semiconductor switching elements (hereinafter referred to as elements) 13A, 13B, 13C, and 13D is electrically connected as switching means. The element 13A and the element 13B are electrically connected to the output terminals 21oa and 21ob of the rectifier 21 in a state of being connected in series. The element 13C and the element 13D are electrically connected to the output terminals 21oa and 21ob of the rectifier 21 in a state where the elements 13C and 13D are connected in series. The element 13A and the element 13B are electrically connected to one input terminal of the transformer 17, and the element 13C and the element 13D are electrically connected to the other input terminal of the transformer 17, so that the inverter circuit 13I is Composed. The operations of the elements 13A, 13B, 13C, and 13D are controlled by the control device 15.

  The inverter circuit 13I simultaneously opens / closes (ON / OFF) the combination of the element 13A and the element 13D, and simultaneously opens / closes (ON / OFF) the combination of the element 13B and the element 13C. At this time, the elements 13B and 13C are simultaneously closed at the timing when the elements 13A and 13D are simultaneously opened, and the elements 13B and 13C are simultaneously opened at the timing when the elements 13A and 13D are simultaneously closed. Thereby, the inverter circuit 13I converts DC power into AC power and inputs the AC power to the transformer 17. Then, the AC power stepped down by the transformer 17 is applied to the power storage device 11.

  FIG. 14 is a schematic diagram illustrating a configuration of a braking device according to a modification of the fourth embodiment. The braking device 10g includes a rectifying device 22 including four diodes on the output side of the transformer 17 included in the braking device 10f illustrated in FIG. The configuration of the rectifier 22 is not limited to this. The braking device 10 g converts the AC power output from the transformer 17 into DC power and applies it to the power storage device 11. If DC power is applied to the power storage device 11 in this way, for example, when the power storage device 11 is configured with passive elements, the choice of passive elements increases, so the degree of freedom in designing the power storage device 11 is improved. . In addition, although the braking device 10g is provided with the interrupter 19 demonstrated in Embodiment 3 between the electrical storage apparatus 11 and the electric power consumption apparatus 12, this is not necessarily required. Moreover, you may provide the interrupter 19 in the braking device 10f shown in FIG. Next, the operation of the braking devices 10f and 10g will be described.

  FIG. 15 is a timing chart when the braking device according to the fourth embodiment operates. SWA and SWB in FIG. 15 indicate the operations of the elements 13A and 13B, and SWC and SWD indicate the operations of the elements 13C and 13D. When the generator 2 of the wind power generator 1 is generating power, the control device 15 of the braking devices 10f and 10g opens all the elements 13A, 13B, 13C, and 13D that constitute the inverter circuit 13I (OFF). As a result, the braking devices 10f and 10g directly output the power generated by the generator 2 from the output terminals Toa and Tob of the braking devices 10f and 10g to the converter.

  When the braking devices 10f and 10g brake the wind power generator 1 (t = t1 in FIG. 15), the control device 15 causes the inverter circuit 13I to function as an inverter. That is, as shown in FIG. 15, the elements 13C and 13D are simultaneously opened (OFF) when the elements 13A and 13B are simultaneously closed (ON), and the elements 13C and 13D are simultaneously closed when the elements 13A and 13B are simultaneously opened. Repeat this periodically. As a result, the DC power is converted into AC power and applied to the transformer 17. The AC power stepped down by the transformer 17 is directly applied to the power storage device 11 in the braking device 10f, and the DC power rectified by the rectifying device 22 is applied to the power storage device 11 in the braking device 10g (FIG. 15). t = t1-t2).

  After it is recognized that the generator 2 has stopped (after t = t2 in FIG. 15), the control device 15 opens all the elements 13A, 13B, 13C, and 13D. As a result, the electric energy stored in the power storage device 11 is consumed by the power consuming device 12. In this case, the control device 15 may close one of the combinations of the elements 13A and 13B or the combinations of the elements 13C and 13D and open the other combination. If it does in this way, since the armature circuit of the generator 2 which comprises the wind power generator 1 is short-circuited by the closed one, the state where the generator 2 and the windmill 3 stopped can be maintained reliably. In addition, when restarting the electric power generation of the wind power generator 1, the control apparatus 15 opens all the elements 13A, 13B, 13C, and 13D.

  As described above, the braking devices 10f and 10g include the inverter circuit 13I including a plurality of elements 13A, 13B, 13C, and 13D as switching means. Thus, the braking devices 10f and 10g can store power in the power storage device 11 when the wind power generator is braked, and the power consuming device 12 consumes the electrical energy stored in the power storage device 11 with one switching unit. Both the generator and the windmill can be stopped.

  As mentioned above, in this embodiment and its modification, a switching means is comprised with a some semiconductor switching element. Thereby, in addition to downsizing of the power consuming means, the functions of the switching means and the short-circuit means can be made compatible.

  As described above, the braking device for wind power generators according to the present invention is useful for braking the wind power generator with the electromagnetic braking device.

DESCRIPTION OF SYMBOLS 1 Wind generator 2 Generator 3 Windmill 4 Input shaft 5 Converter 6 Electric power consumption object 10, 10a, 10b, 10c, 10d, 10e, 10f, 10g Brake device (brake device for wind generators)
11 Power Storage Device 12 Power Consumption Device 13 Switching Device 13A, 13B, 13C, 13D Element (Semiconductor Switching Element)
DESCRIPTION OF SYMBOLS 14 Voltmeter 15M Memory | storage part 15P Processing part 15 Control apparatus 16A Tachometer 16B Anemometer 17 Transformer 18 Short circuit 19 Intermittent 20 Semiconductor switching element 21, 22 Rectifier 21ia, 21ib Input terminal 21oa, 21ob Output terminal

Claims (11)

A power storage means for storing electrical energy generated by a generator that converts wind power into electrical energy, and discharging the stored electrical energy;
A power consuming means for consuming electrical energy stored in the power storage means;
Based on wind speed information indicating the speed of wind driving the generator, switching means for electrically connecting or disconnecting the generator and the power storage means;
Short-circuit means for short-circuiting the output of the generator,
If it is determined that the generator has stopped after the switching means electrically connects the generator and the power storage means, the switching means electrically connects the generator and the power storage means. The braking device for wind power generators which cuts off and the said short-circuit means short-circuits the output of the said generator . The braking apparatus for wind power generators according to claim 1 , further comprising an intermittent means for electrically connecting or disconnecting the power storage means and the power consumption means between the power storage means and the power consumption means. The intermittent means is
After the switching means electrically connects the generator and the power storage means, the power storage means and the power consumption means are electrically shut off while the generator is not recognized to have stopped,
The wind power generator braking device according to claim 2 , wherein the power storage means and the power consumption means are electrically connected after it is recognized that the generator has stopped. The braking device for a wind power generator according to claim 2 or 3 , wherein the intermittent means and the power consuming means are constituted by semiconductor switching elements. The braking device for wind power generators according to any one of claims 1 to 4 , wherein voltage drop means is provided between the generator and the power storage means. The braking device for a wind power generator according to claim 5 , further comprising a rectifying unit between the voltage drop unit and the power storage unit. The switching means is configured by combining a plurality of semiconductor switching elements,
Wind power generator braking system according to any one of claims 1 to 6, electrical energy thus being power to the generator is input into the switching unit is converted into DC power. The switching means is
The wind turbine generator according to any one of claims 1 to 7 , wherein when the wind speed information is equal to or greater than a predetermined threshold value, the generator and the power storage unit are electrically connected. Braking device. A power storage means for storing electrical energy generated by a generator that converts wind power into electrical energy, and discharging the stored electrical energy;
A power consuming means for consuming electrical energy stored in the power storage means;
Based on wind speed information indicating the speed of wind driving the generator, switching means for electrically connecting or disconnecting the generator and the power storage means;
An intermittent means provided between the power storage means and the power consuming means for electrically connecting or disconnecting the power storage means and the power consuming means;
The intermittent means is
After the switching means electrically connects the generator and the power storage means, the power storage means and the power consumption means are electrically shut off while the generator is not recognized to have stopped,
A wind turbine generator braking device comprising: electrically connecting the power storage means and the power consuming means after it is recognized that the generator has stopped. A power storage means for storing electrical energy generated by a generator that converts wind power into electrical energy, and discharging the stored electrical energy;
A power consuming means for consuming electrical energy stored in the power storage means;
Based on wind speed information indicating the speed of wind driving the generator, switching means for electrically connecting or disconnecting the generator and the power storage means;
Voltage drop means provided between the generator and the power storage means ;
A braking device for a wind power generator comprising: A power storage means for storing electrical energy generated by a generator that converts wind power into electrical energy, and discharging the stored electrical energy;
A power consuming means for consuming electrical energy stored in the power storage means;
Switching means for electrically connecting or disconnecting the power generator and the power storage means based on wind speed information indicating the speed of the wind driving the power generator,
The switching means is configured by combining a plurality of semiconductor switching elements,
The generator thus generated electric wind power generator braking system, characterized in that electric energy is inputted to the switching unit is converted into DC power.

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