JP2013537789A - Renewable energy power generator and method of operating the same - Google Patents

Abstract

Regenerative energy that can connect a synchronous generator to a power system without using a frequency conversion circuit, and can improve efficiency during low-load operation and avoid loss of power generation opportunities due to a generator failure if necessary. Provided are a power generation apparatus and an operation method thereof.
A regenerative energy type power generating apparatus (1) includes a rotating shaft (8) that is rotated by regenerative energy received via a blade (4), a hydraulic pump (12) that is driven by the rotating shaft (8) to generate pressure oil, and the pressure oil. A plurality of hydraulic motors 14 _k to be driven and a plurality of synchronous generators 20 _k connected to the power system 50 without passing through the frequency conversion circuit and connected to the plurality of hydraulic motors 14 _k , respectively. The displacement volumes of the plurality of hydraulic motors 14 _k are adjusted independently of each other by the motor control unit 48. Previous the incorporation to the power grid 50 of each synchronous generator 20 _k, so that the frequency and phase of the terminal voltage of each of the synchronous generator 20 _k is synchronized to the power system 50, the command value of the displacement volume of the hydraulic motors 14 _k Is supplied from the synchronizer 120 to the motor control unit 48.
[Selection] Figure 6

Description

  The present invention relates to a regenerative energy type power generating device that generates electric power by transmitting rotation of a rotating shaft to a generator via a hydraulic transmission and supplies the electric power to an electric power system and an operation method thereof. The renewable energy type power generation device is a power generation device using renewable energy such as wind, tidal current, ocean current, river flow, etc., and examples thereof include wind power generation device, tidal current power generation device, ocean current power generation device, river current power generation device and the like. be able to.

  In recent years, from the viewpoint of conservation of the global environment, wind power generators using wind power and renewable energy power generators including power generators using tidal currents, ocean currents, or river currents have been widely used. In the regenerative energy type power generation device, the kinetic energy of wind, tidal current, ocean current or river current is converted into the rotational energy of the rotor, and the rotational energy of the rotor is converted into electric power by the generator.

In this type of renewable energy power generator, the generator is usually linked to a power system. There are various types of generators and how to connect to the electric power system. For example, wind power generators using a method such as that shown in FIGS. 13A and 13B are known.
In the wind turbine generator of the type shown in FIG. 13A, the secondary winding induction generator 520 is connected to the rotor 2 via the speed increaser 500. The secondary winding induction generator 520 has a stator winding connected directly to the power system 50 and a rotor winding connected to the power system 50 via an AC-DC-AC converter 530. The AC-DC-AC converter 530 includes a generator-side inverter 532, a DC bus 534, and a system-side inverter 536. The generator-side inverter 532 enables variable speed operation by controlling the current of the rotor winding and adjusting the generator torque. On the other hand, the system-side inverter 536 converts the power received from the rotor winding of the secondary winding induction generator 520 into AC power adapted to the frequency of the power system 50.
In the method shown in FIG. 13B, the synchronous generator 540 is connected to the rotor 2. The synchronous generator 540 is connected to the power system 50 via the AC-DC-AC link 550. The AC-DC-AC link 550 includes a converter 552, a DC bus 554, and an inverter 556. The AC-DC-AC link 550 enables variable speed operation by adjusting the torque of the synchronous generator 540, and converts the electric power generated by the synchronous generator 540 into AC power adapted to the frequency of the power system 50. Take the role of converting.

Further, as similar to the method shown in FIG. 13B, Patent Document 1 discloses that a synchronous generator connected to a rotor via a speed increaser is connected to an electric power system via a passive rectifier and an inverter. There is disclosed a wind power generator adapted for use.
Patent Document 1 also describes that a plurality of synchronous generators are connected to a gear type gearbox and each synchronous generator is linked to a power system via a passive rectifier and an inverter.

By the way, recently, a regenerative energy type power generation apparatus employing a hydraulic transmission in which a hydraulic pump and a hydraulic motor are combined has attracted attention.
For example, Patent Document 2 describes a wind power generator using a hydraulic transmission in which a hydraulic pump driven by rotation of a rotor and a hydraulic motor connected to a generator are combined. In the hydraulic transmission of this wind power generator, the hydraulic pump and the hydraulic motor are connected to each other via a high pressure reservoir and a low pressure reservoir. Thereby, the rotational energy of the rotor is transmitted to the generator via the hydraulic transmission. The hydraulic pump includes a plurality of sets of pistons and cylinders, and cams that periodically slide the pistons within the cylinders.

European Patent Application No. 2273107 US Patent Application Publication No. 2010/0032959

As described above, conventionally, as a technique for linking a generator of a renewable energy power generation apparatus to a power system, a method as shown in FIGS. 13A and 13B or a method described in Patent Document 1 has been established. ing. However, both methods require expensive frequency conversion circuits.
Note that the frequency conversion circuit refers to a combination of the AC-DC-AC converter 530 illustrated in FIG. 13A, the AC-DC-AC link 550 illustrated in FIG. 13B, and the passive rectifier and the inverter disclosed in Patent Document 1.

In view of this, the present applicant links the synchronous generator to the power system without relying on the frequency conversion circuit in the regenerative energy type power generation apparatus including the hydraulic transmission in which the hydraulic pump and the hydraulic motor are combined as in Patent Document 2. We are considering adopting a new method.
However, in order to link the synchronous generator to the system without using the frequency conversion circuit, it is necessary to synchronize the frequency and phase of the terminal voltage of the synchronous generator to the power system side before entering the power system. . This is different from the induction generator that can be incorporated into the power system as long as the slip (ratio of the difference between the synchronous speed and the generator rotational speed to the synchronous speed) is within a predetermined range. Because the voltage and frequency on the power system side will fluctuate if there is a difference between the instantaneous voltage value on the generator side and the power system side, it is necessary to match both before entering the power system It is.
Patent Documents 1 and 2 describe how to change the frequency and phase of the terminal voltage of the synchronous generator when the synchronous generator of the regenerative energy generator is inserted into the power system without relying on the frequency conversion circuit. There is no description on how to synchronize to the side.

In addition, when only one synchronous generator is provided, the characteristics of the generator, which makes it difficult to obtain high efficiency at low loads, can not only be a barrier to improving efficiency during low load operation of the renewable energy generator, but also the generator. In the event of a failure, the operation of the regenerative energy generator is forced to stop.
In this regard, Patent Document 1 describes a wind power generation apparatus in which a plurality of synchronous generators are connected to an electric power system via passive rectifiers and inverters. However, each synchronous generator is incorporated into the electric power system. There is no specific description of what kind of control is sometimes performed. In particular, Patent Document 1 does not disclose or suggest a method for inserting each synchronous generator into an electric power system without using a frequency conversion circuit. Further, in the wind turbine generator described in Patent Document 1, in addition to the gearbox itself having a heavy weight and a complicated structure, the output of the gearbox is divided into a plurality of parts and the rotation shaft of each synchronous generator is used. It is necessary to provide a gear for taking out, which further increases the weight and cost.

  The present invention has been made in view of the above-described circumstances, and can synchronize a synchronous generator with an electric power system without using a frequency conversion circuit. An object of the present invention is to provide a regenerative energy type power generation apparatus capable of avoiding loss of power generation opportunities due to a failure and an operation method thereof.

  A renewable energy type power generation device according to the present invention is a renewable energy type power generation device that generates electric power by using renewable energy, a blade, a rotating shaft that rotates by the renewable energy received through the blade, A hydraulic pump that is driven by the rotating shaft to generate pressure oil, a plurality of hydraulic motors that are driven by the pressure oil, and a power system that does not go through a frequency conversion circuit, and each of the plurality of hydraulic motors A plurality of synchronous generators to be connected; a motor control unit that independently adjusts displacements of the plurality of hydraulic motors; and a terminal of each synchronous generator before the synchronous generators are incorporated into the power system. A sync that provides the motor controller with a command value for the displacement volume of each hydraulic motor so that the frequency and phase of the voltage are synchronized with the power system. Characterized in that it comprises a homogenizer.

In this regenerative energy type power generator, the command value of the displacement volume of the hydraulic motor from the synchronizer is set so that the frequency and phase of the terminal voltage of each synchronous generator is synchronized with the power system before each synchronous generator is incorporated. Is given to the motor controller. Therefore, even if there is no frequency conversion circuit between each synchronous generator and the power system, a state where the synchronous generator can be inserted into the power system is created by the synchronizer without relying on the frequency conversion circuit. Can do.
Further, since the displacements of the plurality of hydraulic motors are adjusted independently of each other, a set used for operation can be arbitrarily selected from among a plurality of sets of synchronous generators and hydraulic motors. Therefore, operation can be performed using only a partial set of the synchronous generator and the hydraulic motor as necessary. For example, in order to improve the overall efficiency of the renewable energy type power generator during low-load operation, the number of sets used for the operation of the synchronous generator and the hydraulic motor is reduced, or the power generation when the synchronous generator and the hydraulic motor fail In order to avoid this lost opportunity, it is possible to continue power generation using a set of a synchronous generator and a hydraulic motor that have not failed.

In the regenerative energy generator, the motor control unit maintains the pressure of the pressure oil at a target pressure based on an output target value of each hydraulic motor after the synchronous generator is inserted into the power system. In this way, the displacement volume of the hydraulic motor may be adjusted.
When the synchronous generator is inserted into the power system, an effective cross current that tries to make the frequency and phase of the terminal voltage of the synchronous generator coincide with those of the power system is generated between the synchronous generator and the power system. For this reason, after the synchronous generator is inserted into the power system, it is not essential to actively synchronize the frequency and phase of the terminal voltage of the synchronous generator with the power system. Therefore, as described above, after the synchronous generator is incorporated into the power system, the hydraulic pressure supplied to the hydraulic motor is maintained at the target pressure based on the output target value of each hydraulic motor. By adjusting the displacement of the motor, the regenerative energy generator can be stably operated.

If two or more synchronous generators are to be synchronized at the same time, the displacement of the hydraulic motor displacement for synchronization of one synchronous generator becomes a disturbance, making it difficult to synchronize other synchronous generators. To.
Therefore, in the renewable energy type power generator, when the synchronous generator and the hydraulic motor are respectively provided with N pieces (where N is an integer of 2 or more), the N synchronous generators are provided with the regeneration unit. The motor control unit sequentially inserts each synchronous generator into the power system in accordance with an increase in the flow rate of energy, and sets the hydraulic pressure based on the command value from the synchronizer before the synchronous generator is added to the power system. The displacement of the motor may be adjusted. The “renewable energy flow rate” means, for example, the wind speed when the renewable energy type power generation device is a wind power generation device, and when the renewable energy type power generation device is a tidal current power generation device, an ocean current power generation device, a river current power generation device, or the like. It means the speed of water flow.
In this way, N synchronous generators are sequentially inserted according to the increase in the flow rate of the regenerative energy, and the displacement volume of each hydraulic motor is adjusted before each synchronous generator is inserted, so that the terminal voltage can be reduced. A state where the frequency and phase are synchronized with the power system can be easily created for each synchronous generator.

When N synchronous generators are sequentially inserted in accordance with an increase in the flow rate of the regenerative energy, the motor control unit is ith of the N (where i is in the range of 1 to (N-1)). The output of the i-th synchronous generator is larger than the minimum load of the synchronous generator and smaller than the rated output of the synchronous generator. After the displacement volume of the i-th hydraulic motor connected to the i-th synchronous generator is increased until reaching, the (i + 1) -th synchronous generator out of the N pieces is inserted into the power system. The displacement volume of the (i + 1) th hydraulic motor connected to the (i + 1) th synchronous generator may be adjusted based on the command value from the synchronizer.
In this way, after the i-th synchronous generator is inserted, it waits for the output to increase to a set value larger than the minimum load, and then the preparation (synchronization) of the (i + 1) -th synchronous generator is performed. By doing so, it is possible to reduce the number of generators used during low-load operation and improve the overall efficiency of the renewable energy power generator during low-load operation. Further, by making the set value less than the rated output of the synchronous generator, an increase margin of the output of the i-th synchronous generator corresponding to the difference between the rated output and the set value is secured, and the (i + 1) -th synchronous generator is secured. Unstable pressure oil energy at the time of synchronization of the generator can be absorbed by controlling the displacement of the i-th hydraulic motor (rising margin of the i-th synchronous generator). Therefore, the (i + 1) th hydraulic motor can be dedicated to the synchronization of the (i + 1) th synchronous generator, and the synchronization of the (i + 1) th synchronous generator is facilitated.

The set value may be not less than 50% and less than 100% of the rated output of the i-th synchronous generator.
According to the knowledge of the present inventors, the efficiency drop becomes significant under a low load condition of less than 50% of the rated output of a general synchronous generator. Therefore, the set value should be 50% or more of the rated output. Thus, the overall efficiency of the regenerative energy power generator during low-load operation can be effectively improved. Further, by setting the set value to be less than the rated output of the synchronous generator, for the reason described above, the synchronization of the (i + 1) th synchronous generator is facilitated.

Alternatively, when the motor control unit sequentially inserts N synchronous generators according to an increase in the flow rate of the regenerative energy, the i-th of the N (where i is in the range of 1 to (N-1)). 1st to i-th hydraulic motors so that the outputs of the 1st to i-th i.s. synchronous generators are maintained at the minimum load after the synchronous generator of any integer in FIG. The (i + 1) th of the N (i + 1) th synchronous generators are adjusted based on the command value from the synchronizer before entering the power system while adjusting the displacement of each of the N. The displacement volume of the (i + 1) th hydraulic motor connected to the synchronous generator may be adjusted.
As a result, operation is performed using all N sets of synchronous generators and hydraulic motors except for an extremely low load operation region close to the cut-in flow velocity that is the power generation start point of the renewable energy power generation device. Therefore, except for an extremely low load operation region close to the cut-in flow rate, each set of synchronous generators and hydraulic motors can be handled in the same manner, and simple operation control becomes possible. In addition, variations in the frequency of use of each set of synchronous generators and hydraulic motors can be reduced.

In addition, when N synchronous generators are sequentially inserted in accordance with an increase in the flow rate of the regenerative energy, the regenerative energy type power generator includes a pitch control unit that adjusts the pitch angle of the blade and a displacement of the hydraulic pump. A pump control unit for adjusting the volume, so that the rotational speed of the rotary shaft is maintained at the target rotational speed before the first synchronous generator among the N synchronous generators is incorporated into the power system. In a state where the displacement angle of the hydraulic pump is adjusted by the pump control unit so that the pitch angle of the blade is adjusted by the pitch control unit and the pressure of the pressure oil is maintained at a target pressure, the motor control unit However, the displacement volume of the first hydraulic motor connected to the first synchronous generator may be adjusted based on the command value from the synchronizer.
In the regenerative energy generator, since the amount of regenerative energy received by the blades changes every moment, the number of rotations of the rotating shaft and the pressure of the pressure oil supplied to the hydraulic motor also fluctuate, and the first synchronous generator synchronizes. Can be a disturbance when performing. Therefore, as described above, the rotational speed of the rotary shaft is maintained at the target rotational speed by adjusting the pitch angle of the blade, and the pressure of the hydraulic oil is maintained at the target pressure by adjusting the displacement of the hydraulic pump, so that the rotational speed of the rotary shaft is maintained. And by synchronizing the pressure oil pressure, the first synchronous generator can be easily synchronized.

Further, when N synchronous generators are sequentially inserted in accordance with an increase in the flow rate of the regenerative energy, the cumulative operating time of each set of the synchronous generator and the hydraulic motor, and each synchronous generator and the power system The order in which the synchronous generators are inserted may be determined based on at least one of the number of times of opening and closing of each circuit breaker that switches the connection state between the synchronous generators.
As a result, the frequency of use of each set of the synchronous generator and the hydraulic motor is equalized to avoid the extreme deterioration of some of the synchronous generator and the hydraulic motor, thereby improving the reliability of the entire regenerative energy type generator. be able to.

Further, when N synchronous generators are sequentially inserted according to an increase in the flow rate of the regenerative energy, the regenerative energy type power generator further includes a pump control unit that adjusts a displacement volume of the hydraulic pump, The output of the i-th synchronous generator gradually increases after the i-th synchronous generator (where i is an arbitrary integer in the range of 1 to (N-1)) is incorporated into the power system. The displacement of the hydraulic pump is adjusted by the pump controller, and the displacement of the i-th hydraulic motor connected to the i-th synchronous generator is adjusted by the motor controller. Also good.
In this way, after the i-th synchronous generator is incorporated into the power system, the output of the i-th synchronous generator is gradually increased, so that the rotational speed of the rotary shaft and the pressure oil supplied to the hydraulic motor can be reduced. The output of the i-th synchronous generator can be increased without impairing pressure stability.

Further, when N synchronous generators are sequentially inserted in accordance with an increase in the flow rate of the regenerative energy, when the rated output of the regenerative energy type power generator is set to P _rated , M of the N (however, M _May be generated at an output of P _rated × (N−M) / N or less at the time of failure of the synchronous generator of 1 or more (N−1).
As a result, even if some of the synchronous generators fail, the partial load operation of the regenerative energy type power generation device can be continued, and lost generation opportunities can be avoided.

  When the flow rate of the regenerative energy is lower than the cut-in flow rate that is the power generation start point of the regenerative energy type power generation device, all the synchronous generators that are incorporated in the power system are disconnected and the regeneration is performed. You may stop the electric power generation of an energy type electric power generating apparatus.

  Further, when all the synchronous generators are disconnected, the power to be supplied to the auxiliary machine of the regenerative energy generator may be generated by at least one of the synchronous generators.

In the regenerative energy type power generator, each hydraulic motor includes a plurality of working chambers surrounded by cylinders and pistons, a plurality of high-pressure valves for supplying the pressure oil to the working chambers, and the pressure from each working chamber. A plurality of low-pressure valves for discharging oil, and a casing in which the working chamber, the high-pressure valve and the low-pressure valve are housed, and further including a start valve provided outside the casing corresponding to each hydraulic motor When starting each hydraulic motor, the motor control unit switches each hydraulic motor by adjusting the number of working chambers in which the pressure oil is supplied and discharged by opening and closing control of the start valve and the low pressure valve. Accelerate to the target rotational speed, adjust the number of the working chambers where the pressure oil is supplied and discharged by the opening and closing control of the high pressure valve and the low pressure valve, each hydraulic motor exceeds the valve switching target rotational speed More Acceleration may be.
For hydraulic motors having working chambers, high-pressure valves and low-pressure valves, open or close using an oil line (high-pressure oil line or low-pressure oil line) connecting between the hydraulic pump and the hydraulic motor and each working chamber. A compact high pressure valve designed to assist is sometimes used. This type of high-pressure valve can be opened and closed only by using the pressure difference created by the reciprocating motion of the piston, with sufficient inertia generated in the rotating shaft of the hydraulic motor. For this reason, a start valve is provided outside the casing separately from the high pressure valve, and the starter valve and the low pressure valve are used for acceleration until the hydraulic motor reaches the target valve switching speed. By using the high-pressure valve and the low-pressure valve, the hydraulic motor can be reliably started.

  The renewable energy type power generation device may be a wind power generation device that generates electric power from wind as the renewable energy.

  A method for operating a regenerative energy generator according to the present invention includes a rotating shaft that is rotated by regenerative energy received via a blade, a hydraulic pump that is driven by the rotating shaft to generate pressure oil, and is driven by the pressure oil. And a plurality of synchronous generators coupled to the plurality of hydraulic motors, respectively, wherein the frequency and phase of the terminal voltage of each synchronous generator are After the step of adjusting the displacement of the plurality of hydraulic motors independently of each other based on the command value from the synchronizer so as to synchronize with the power system, and the step of adjusting the displacement, a frequency conversion circuit And a step of inserting the plurality of synchronous generators into the power system without interposing them.

In the operation method of the regenerative energy type power generator described above, based on the command value from the synchronizer so that the frequency and phase of the terminal voltage of each synchronous generator are synchronized with the power system before the synchronous generator is inserted. The displacement of the hydraulic motor is adjusted. Therefore, even if there is no frequency conversion circuit between each synchronous generator and the power system, a state where the synchronous generator can be inserted into the power system is created by the synchronizer without relying on the frequency conversion circuit. Can do.
Further, since the displacements of the plurality of hydraulic motors are adjusted independently of each other, a set used for operation can be arbitrarily selected from among a plurality of sets of synchronous generators and hydraulic motors. Therefore, operation can be performed using only a partial set of the synchronous generator and the hydraulic motor as necessary. For example, in order to improve the overall efficiency of the renewable energy type power generator during low-load operation, the number of sets used for the operation of the synchronous generator and the hydraulic motor is reduced, or the power generation when the synchronous generator and the hydraulic motor fail In order to avoid this lost opportunity, it is possible to continue power generation using a set of a synchronous generator and a hydraulic motor that have not failed.

  According to the present invention, by adjusting the displacement volume of each hydraulic motor based on the command value from the synchronizer, it is possible to create a state in which the synchronous generator can be inserted into the power system without depending on the frequency conversion circuit. In addition, since the displacement of the plurality of hydraulic motors connected to each synchronous generator is adjusted independently of each other, a set used for operation can be arbitrarily selected from among the plurality of sets of synchronous generators and hydraulic motors. . Therefore, only a partial set of the synchronous generator and the hydraulic motor can be used for operation as required.

It is a figure which shows an example of the whole structure of a wind power generator. It is a figure which shows the structure of the hydraulic transmission and transmission control part of a wind power generator. It is a figure which shows the structure of a hydraulic transmission. It is a figure which shows the specific structural example of a hydraulic pump. It is a figure which shows the specific structural example of a hydraulic motor. It is a figure which shows the structural example of a synchronous generator periphery. It is a graph which shows an example of a time-dependent change of various parameters before and behind insertion of a synchronous generator. It is a figure for demonstrating an example of the procedure which inserts two synchronous generators into an electric power grid | system. It is a figure for demonstrating the other example of the procedure which inserts two synchronous generators into an electric power grid | system. It is a figure which shows the signal flow at the time of the displacement volume of a hydraulic pump being determined in a transmission control part. The horizontal axis of the rotor rotational speed W _r, is a graph showing the Cp maximum curve in the coordinate system on the vertical axis of the rotor torque T. It is a figure which shows the signal flow at the time of the displacement volume of a hydraulic motor being determined in a transmission control part. It is a figure which shows the example of the conventional wind power generator.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention unless otherwise specified, and are merely illustrative examples. Only.

  In the following embodiments, a wind power generator will be described as an example of a renewable energy power generator. However, the present invention can also be applied to other renewable energy power generation devices such as tidal current power generation devices, ocean current power generation devices, and river current power generation devices.

[Configuration of wind power generator]
FIG. 1 is a diagram illustrating an example of the overall configuration of a wind turbine generator. FIG. 2 is a diagram illustrating a configuration of a hydraulic transmission and a transmission control unit of the wind turbine generator. FIG. 3 is a diagram showing a configuration of the hydraulic transmission. FIG. 4 is a diagram showing a specific configuration example of the hydraulic pump. FIG. 5 is a diagram showing a specific configuration example of the hydraulic motor.

As shown in FIG. 1, the wind power generator 1 mainly includes a rotor 2 that rotates by receiving wind, a hydraulic transmission 10 that accelerates the rotation of the rotor 2, and a synchronous generator 20 that is linked to an electric power system. A transmission control unit 40 (see FIG. 2) for controlling the hydraulic transmission 10 and various measuring instruments including a pressure gauge 31 and rotation speed meters 32 and 36 are provided.
The hydraulic transmission 10 and the synchronous generator 20 may be accommodated in the nacelle 22 or the tower 24 that supports the nacelle 22. Although FIG. 1 shows the onshore wind power generation apparatus in which the tower 24 is erected on the ground, the wind power generation apparatus 1 may be installed at any place including the ocean.

  The rotor 2 has a configuration in which a rotating shaft 8 is connected to a hub 6 to which blades 4 are attached. That is, three blades 4 extend radially around the hub 6, and each blade 4 is attached to the hub 6 connected to the rotary shaft 8. As a result, the entire rotor 2 is rotated by the wind force received by the blade 4, and rotation is input to the hydraulic transmission 10 via the rotating shaft 8. An actuator 5 (see FIG. 2) is attached to the blade 4. The actuator 5 operates under the control of the pitch controller 7 and changes the pitch angle of the blade 4.

2 and 3, the hydraulic transmission 10 includes a variable displacement hydraulic pump 12 driven by a rotating shaft 8 and a synchronous generator 20 _k (where k is an arbitrary integer in the range of 1 to N). A variable displacement hydraulic motor 14 _k having an output shaft 15 connected thereto, and a high-pressure oil line 16 and a low-pressure oil line 18 provided between the hydraulic pump 12 and the hydraulic motor 14 _k are provided. In the wind turbine generator 1, the hydraulic motor 14 _k and the synchronous generator 20 _k, respectively, N in number (where N is an integer of 2 or more) is provided.

The discharge side of the hydraulic pump 12 is connected to the suction side of each hydraulic motor 14 _k by a high-pressure oil line 16, and the suction side of the hydraulic pump 12 is connected to the discharge side of each hydraulic motor 14 _k by a low-pressure oil line 18. Has been. As shown in FIG. 3, the N hydraulic motors 14 _k are connected to the high-pressure oil line 16 and the low-pressure oil line 18 in parallel with each other. The pressure oil (high pressure oil) generated by the hydraulic pump 12 flows into the hydraulic motor 14 _k via the high pressure oil line 16 and drives the hydraulic motor 14 _k . The hydraulic oil (low pressure oil) that has been operated by the hydraulic motor 14 _k flows into the hydraulic pump 12 via the low pressure oil line 18, is pressurized by the hydraulic pump 12, and then is hydraulically returned via the high pressure oil line 16. and it flows into the motor 14 _k.

The hydraulic pump 12 and the hydraulic motor 14 _k may have specific configurations as shown in FIGS. 4 and 5 as described below.

As shown in FIG. 4, the hydraulic pump 12 includes a plurality of working chambers (working chambers) 83 formed by a cylinder 80 and a piston 82, a ring cam 84 having a cam curved surface that engages with the piston 82, and each working chamber 83. The high pressure valve 86 and the low pressure valve 88 may be provided. The high pressure valve 86 is provided in the high pressure communication path 87 between each working chamber 83 and the high pressure oil line 16, and the low pressure valve 88 is provided in the low pressure communication path 89 between each working chamber 83 and the low pressure oil line 18. It has been.
When the ring cam 84 rotates together with the rotary shaft 8 during operation of the hydraulic pump 12, the piston 82 periodically moves up and down in accordance with the cam curve, and the piston 82 moves from the bottom dead center to the top dead center. The inhalation process in which 82 is directed from the top dead center to the bottom dead center is repeated. Therefore, the volume of the working chamber 83 formed by the piston 82 and the inner wall surface of the cylinder 80 changes periodically.
In the hydraulic pump 12, each working chamber 83 can be switched to an active state or an idling state by opening / closing control of the high pressure valve 86 and the low pressure valve 88. When the working chamber 83 is in an active state, the high pressure valve 86 is closed in the suction process and the low pressure valve 88 is opened to allow the working oil to flow into the working chamber 83 from the low pressure oil line 18 and the high pressure valve 86 is opened in the pump process. By closing the low pressure valve 88, the hydraulic oil compressed from the working chamber 83 to the high pressure oil line 16 is sent out. On the other hand, when the working chamber 83 is in the idling state, the high pressure valve 86 is closed and the low pressure valve 88 is opened in both the suction process and the pump process, and the working chamber 83 and the low pressure oil line 18 are maintained. The hydraulic oil is reciprocated at (that is, the hydraulic oil is not sent to the high-pressure oil line 16). Therefore, the displacement volume of the hydraulic pump 12 as a whole can be adjusted by changing the ratio of the number of working chambers 83 in the active state to the total number of working chambers. Adjustment of the displacement of the hydraulic pump 12 as a whole is performed by a transmission control unit 40 described later.

As shown in FIG. 5, the hydraulic motor 14 _k has a plurality of working chambers 93 formed by cylinders 90 and pistons 92, an eccentric cam 94 having a cam curved surface that engages with the pistons 92, and each working chamber 93. The high-pressure valve 96 and the low-pressure valve 98 provided may be provided. The high pressure valve 96 is provided in the high pressure communication passage 97 between each working chamber 93 and the high pressure oil line 16, and the low pressure valve 98 is provided in the low pressure communication passage 99 between each working chamber 93 and the low pressure oil line 18. It has been.
During operation of the hydraulic motor 14 _k, the differential pressure between the high pressure oil line 16 and the low pressure oil line 18 to the hydraulic pump 12 is made, the piston 92 is periodically moved up and down, the bottom dead center piston 92 from the top dead center And the discharge process of the piston 92 from the bottom dead center to the top dead center are repeated. During operation of the hydraulic motor 14 _k, the volume of the working chamber 93 formed by the inner wall surface of the piston 92 and the cylinder 90 changes periodically.
The hydraulic motor 14 _k can switch each working chamber 93 to an active state or an idling state by opening / closing control of the high pressure valve 96 and the low pressure valve 98. When the working chamber 93 is in the active state, the high pressure valve 96 is opened in the motor process and the low pressure valve 98 is closed to allow the working oil to flow into the working chamber 93 from the high pressure oil line 16 and in the discharge process, the high pressure valve 96 is closed. By opening the low pressure valve 98, the working oil that has worked in the working chamber 93 is sent out to the low pressure oil line 18. On the other hand, when the working chamber 93 is in an idling state, the high pressure valve 96 is closed and the low pressure valve 98 is opened in both the motor process and the pump process, and the working chamber 93 and the low pressure oil line 18 are maintained. The hydraulic oil is reciprocated at (that is, the high pressure oil from the high pressure oil line 16 is not received in the working chamber 93). Thus, the hydraulic motor 14 _k, like the hydraulic pump 12, by changing the percentage of total operating rooms of the number of working chambers 93 in the active state, it is possible to adjust the displacement volume as a whole. Regulation of the displacement volume of the whole of the hydraulic motor 14 _k is performed by the transmission control unit 40 described later.
The working chamber 93, the eccentric cam 94, the high pressure valve 96 and the low pressure valve 98 are housed in the casing 91. A start valve 17 is provided outside the casing 91 on a flow path that bypasses the high-pressure valve 96 and connects the high-pressure oil line 16 and the working chamber 93. The starting valve 17, to accelerate the hydraulic motor 14 _k at the time of starting of the hydraulic motor 14 _k to a predetermined revolution speed, it is used together with the low-pressure valve 98. The start valve 17 may be provided corresponding to each working chamber 93 or may be provided corresponding to only a part of the working chambers 93.

Further, as shown in FIG. 2, an accumulator 64 is connected to the high pressure oil line 16. The accumulator 64 can absorb fluctuations in the pressure of the hydraulic oil in the high-pressure oil line 16 due to the difference between the energy generated by the hydraulic motor 12 and the energy consumed by all the hydraulic motors 14 _k . Therefore, the pressure P _s of the high pressure oil line 16 can be stabilized by the accumulator 64, the control of the hydraulic motor 14 _k is facilitated when combined synchronization of the synchronous generator 20 _k.
An electromagnetic valve 66 may be provided between the high pressure oil line 16 and the accumulator 64. By opening and closing the electromagnetic valve 66, the accumulator 64 communicates with the high pressure oil line 16 or is disconnected from the high pressure oil line 16. In the case of providing a solenoid valve 66, by opening the electromagnetic valve 66 during mating synchronization of the synchronous generator 20 _k, it may stabilize the pressure P _s of the high pressure oil line 16 with the accumulator 64.

Between the high-pressure oil line 16 and the low-pressure oil line 18, a bypass passage 60 that bypasses all the hydraulic motors 14 _k is provided. The bypass passage 60 is provided with a relief valve 62 that keeps the pressure of the hydraulic oil in the high-pressure oil line 16 below a set pressure. As a result, when the pressure in the high pressure oil line 16 rises to the set pressure of the relief valve 62, the relief valve 62 automatically opens and the high pressure oil is allowed to escape to the low pressure oil line 18 via the bypass flow path 60. it can.

Further, the hydraulic transmission 10 is provided with an oil tank 70, a replenishment line 72, a boost pump 74, an oil filter 76, a return line 78, and a low pressure relief valve 79.
The oil tank 70 stores hydraulic oil for replenishment. The replenishment line 72 connects the oil tank 70 to the low pressure oil line 18. The boost pump 74 is provided in the replenishment line 72 to replenish hydraulic oil from the oil tank 70 to the low-pressure oil line 18.
The return line 78 is disposed between the oil tank 70 and the low pressure oil line 18. The low-pressure relief valve 79 is provided in the return line 78 and is configured to keep the pressure in the low-pressure oil line 18 equal to or lower than the set pressure. Thereby, even if the hydraulic oil is supplied to the low pressure oil line 18 by the boost pump 74, the low pressure relief valve 79 is automatically opened if the pressure in the low pressure oil line 18 reaches the set pressure of the low pressure relief valve 79. The hydraulic oil can be released to the oil tank 70 via the return line 78.

As shown in FIG. 2, the wind turbine generator 1 is provided with revolution speed meters 32 and 34 and a pressure gauge 31. The tachometers 32 and 34 measure the rotation speed of the rotary shaft 8 and the rotation speed of the output shaft 15 of the hydraulic motor 14 _k , respectively. The pressure gauge 31 measures the pressure of hydraulic oil (high pressure oil) in the high pressure oil line 16. Further, an anemometer 33 that is attached to the outside of the nacelle 22 and measures the wind speed, and a temperature sensor 34 that measures the ambient temperature around the wind turbine generator 1 may be provided. The measurement results obtained by these various measuring instruments may be sent to the transmission control unit 40 and used for controlling the hydraulic pump 12 and the hydraulic motor _14k .

A synchronous generator 20 _k is connected to the output shaft 15 of the hydraulic motor 14 _k . The synchronous generator 20 _k is linked to the power system 50 without passing through the frequency conversion circuit (for example, the frequency conversion circuits 530 and 550 in FIGS. 13A and 13B).
In addition, since the wind power generator generally has a large output fluctuation, it becomes a fluctuation factor of the frequency of the power system when connected to the power system in large numbers, but the output is smoothed by operating the wind power generator at a variable speed, The influence on the power system can be mitigated. Therefore, the wind power generator 1 enables variable speed operation by controlling the hydraulic transmission 10 by the transmission control unit 40 (normal control mode). Details of the normal control mode of the transmission control unit 40 will be described later.

FIG. 6 is a diagram illustrating a configuration example around the synchronous generator 20 _k . As shown in the figure, the synchronous generator 20 _k includes a field winding 21 that rotates together with the output shaft 15 of the hydraulic motor 14 _k , and a fixed armature (not connected) connected to the power system 50 via a circuit breaker 122. As shown). A DC field current is supplied from the exciter 100 to the field winding 21.
Note that the magnitude of the field current supplied to the field winding 21 is controlled by the exciter controller 110. The exciter controller 110 controls the exciter 100 based on the measured value of the terminal voltage of the synchronous generator 20 by the terminal voltage detector (potential transformer) 59 so that the terminal voltage becomes a set value. You may control.

As a specific configuration of the exciter 100, for example, an AC exciter as shown in FIG. 6 may be adopted. That is, the exciter 100 may be an AC generator configured with a rotating armature (not shown) and a field winding (stator) 102.
In this case, the exciter 100 is an AC exciter that is directly connected to the output shaft 15 of the hydraulic motor 14 _k , and the AC current output from the rotating armature of the exciter 100 is converted to DC by the rectifier (rotary rectifier) 103. Thereafter, this is supplied as a field current to the field winding 21 of the synchronous generator 20 _k . The field winding 21, the armature of the exciter 100, and the rectifier 103 are portions that rotate together with the output shaft 15 of the hydraulic motor _14k . As described above, the AC current from the rotary armature of the AC exciter 100 is rectified by the rectifier (rotary rectifier) 103 and supplied to the field winding 21 that is the rotor, so that the brush can be omitted. , Maintenance (periodic replacement) of the brush becomes unnecessary. Since wind power generators are generally installed in mountainous areas and offshore areas such as offshore, the need for brush maintenance (periodic replacement) greatly contributes to a reduction in running costs.

In the example shown in FIG. 6, the exciter control unit 110 changes the field current supplied to the field winding 102 of the exciter 100 to change the field winding of the synchronous generator 20 _k. The magnitude of the field current flowing through 21 is adjusted.
In this case, as shown in FIG. 6, the exciter control unit 110 may include a comparison circuit 113, an automatic voltage regulator (AVR) 114, and a thyristor 116. The comparison circuit 113 compares the measured value of the terminal voltage of the synchronous generator 20 _k by the terminal voltage detector 59 with the set value input from the synchronizer 120, and outputs the deviation between them to the AVR 114. The AVR 114 supplies a gate signal to the thyristor 116 based on the deviation output from the comparison circuit 113. The thyristor 116 is provided between the field winding 102 of the exciter 100 and a sub exciter composed of a permanent magnet generator (PMG) 106 directly connected to the output shaft 15 of the hydraulic motor 14 _k. ing. The thyristor 116 excites the field winding (fixed field) 102 of the exciter 100 using a permanent magnet generator (sub-exciter) 106 as a power source.
Thus, is directly connected to the output shaft 15 of the hydraulic motor 14 _k, by using a permanent magnet generator 106 provided to the synchronous generator 20 _k coaxially as a power source of the thyristor 116, the power of the synchronous generator 20 _k even before the incorporation into the system 50, it is possible to perform excitation of the synchronous generator 20 _k without the need for external power supply. This is very advantageous in a wind turbine generator that generally has a property that it is difficult to obtain an external power source.

[Control before and after synchronous generator]
In the wind turbine generator 1, a synchronizer 120 is used for inserting each synchronous generator 20 _{k into} the power system 50.
The synchronizer 120 receives the measurement result of the terminal voltage of the synchronous generator 20 _k by the terminal voltage detector 124 and the measurement result of the voltage of the power system 50 by the system voltage detector 126, and these are received by each synchronous generator 20 _k. Used for synchronization. The synchronizer 120, when the synchronous generator 20 _k is inserted into the power system 50, the terminal voltage of the synchronous generator 20 _k measured by the terminal voltage detector 124 and the voltage of the power system 50 measured by the system voltage detector 126. A command value for the displacement volume of the hydraulic motor 14 _k is provided to the motor control unit 48 so that the frequency difference and the phase difference between the motor and the motor 14 _k fall within a predetermined range. The motor controller 48 adjusts the displacement of the hydraulic motor 14 _k according to the command value from the synchronizer 120, so that the frequency and phase of the terminal voltage of the synchronous generator 20 _k are synchronized with the power system 50. Thereafter, the circuit breaker 122 is closed according to the signal from the synchronizer 120, and the synchronous generator 20 _k is inserted into the power system 50.
Note that, before the synchronous generator 20 _k enters the power system 50, the difference between the set value (voltage of the power system 50) input from the synchronizer 120 and the terminal voltage of the synchronous generator 20 _k falls within a predetermined range. As described above, the exciter control unit 110 is controlled. That is, based on the error output from the comparator circuit 113, AVR114 supplies a gate signal to the thyristor 116, the magnitude of the field current flowing through the field winding 21 of the synchronous generator 20 _k is adjusted.

FIG. 7 is a graph showing an example of changes over time in various parameters before and after the synchronous generator 20 _k is inserted.
Prior to time T _0, the hydraulic motor 14 _k and the synchronous generator 20 _k are stopped. Therefore, the rotational speed of the hydraulic motor 14 _k is zero, the torque of the hydraulic motor 14 _k is zero, the phase difference between the synchronous generator 20 _k side and the power grid 50 side between 180 ° ~-180 ° It changes greatly and periodically.

It begins the starting of the hydraulic motor 14 _k at time _{T 0.} First, at t = T _{0 to} T ₁ , the start valve 17 and the low pressure valve 98 are opened and closed based on the measured value of the revolution meter 36 under the control of the motor control unit 48, and supply of pressure oil to the working chamber 93 is performed. Repeat discharge, increases the rotational speed of the hydraulic motor 14 _k to a predetermined rotational speed w _0. When the rotational speed of the hydraulic motor 14 _k reaches w ₀ at t = T ₁ , switching to acceleration of the hydraulic motor 14 _k using the high pressure valve 96 and the low pressure valve 98 is performed. Then, at t = T _{1 to} T ₂ , the high-pressure valve 96 and the low-pressure valve 98 are opened and closed based on the measured value of the revolution meter 36 under the control of the motor control unit 48, and supply of pressure oil to the working chamber 93 and The discharge is repeated, and the rotational speed of the hydraulic motor 14 _k is increased to a predetermined rotational speed w ₁ before the rated rotational speed w _rated . At this time, in order to quickly reach the rotational speed w ₁ of the hydraulic motor 14 _k , all the working chambers 93 may be activated to maximize the displacement volume of the hydraulic motor 14 _k .

Thereafter, at time T _2, it starts controlling the hydraulic motor 14 _k for synchronizing the frequency of the terminal voltage of the synchronous generator 20 _k to the power system 50. Specifically, the motor control unit 48 adjusts the displacement volume of the hydraulic motor 14 _k (the number of the active chambers 93 in the active state) according to the signal from the synchronizer 120, and sets the rotation speed of the hydraulic motor 14 _k to the rated rotation speed. w _Move closer. Here, the rated rotational speed w _rated is the rotational speed of the hydraulic motor 14 _k at which the frequency of the terminal voltage of the synchronous generator 20 _k matches that of the power system 50. Incidentally, before the start of this control, previously activated the excitation system of the synchronous generator 20 _k.

Then, at time T ₃ , the control shifts to the control of the hydraulic motor 14 _k for synchronizing the phase of the terminal voltage of the synchronous generator 20 _k with the power system 50. Specifically, the motor control unit 48 adjusts the displacement volume (the number of active chambers 93 in the active state) of the hydraulic motor 14 _k in accordance with a signal from the synchronizer 120, and the synchronous generator 20 _k side and the power system 50 side So that the phase difference between and falls within a predetermined range. When the phase difference of the synchronous generator 20 _k side and the power grid 50 side within a predetermined range at time T _4, waiting for the other conditions are met, the circuit breaker by a signal from the synchronizer 120 at time T ₅ 122 is closed and the synchronous generator 20 _k is inserted into the power system 50. Here, the other condition is that the difference between the terminal voltage of the synchronous generator 20 _k and the system voltage is within a predetermined range. This condition is applied to the field winding 21 by the exciter control unit 110. It is satisfied by controlling the flowing field current.
Thereafter, gradually increasing the torque of the hydraulic motor 14 _k, increases the output of the synchronous generator 20 _k.

By the way, if two or more synchronous generators 20 _k are simultaneously synchronized, the change in displacement of the hydraulic motor for synchronization of one synchronous generator becomes a disturbance, and the synchronization of other synchronous generators Make alignment difficult.
Thus, in the present embodiment, N synchronous generators 20 _k are sequentially inserted into the power system 50 in accordance with the increase in wind speed, and the timings at which the synchronous generators 20 _k are inserted into the power system 50 are different from each other. Make it. This makes it possible to frequency and phase of the terminal voltage is easily create for each synchronous generator 20 _k single state in synchronism with the power system.
Hereinafter, the i-th synchronous generator 20 _k is referred to as a synchronous generator 20 _i .

When the synchronous generator 20 _i is sequentially turned on, the cumulative operating time of each set of the synchronous generator 20 _i and the hydraulic motor 14 _i and each circuit breaker 122 between each synchronous generator 20 _i and the power system 50 are displayed. The order in which the synchronous generators 20 _i are inserted may be determined based on the number of times of opening and closing.
As a result, the usage frequency of each set of the synchronous generator 20 _i and the hydraulic motor 14 _i is equalized, and extreme deterioration of a part of the synchronous generator 20 and the hydraulic motor 14 is avoided, so that the wind power generator 1 as a whole is achieved. Reliability can be improved.

For example, after the i-th (where i is an arbitrary integer in the range of 1 to (N-1)) synchronous generator 20 _i is incorporated into the power system 50, the output of the i-th synchronous generator 20 _i is set. After increasing to the value X, the (i + 1) -th synchronous generator 20 _{i + 1} may be synchronized. That is, after the i-th synchronous generator 20 _i enters the power system 50, the motor control unit 48 increases the torque of the hydraulic motor 14 _i to increase the output of the synchronous generator 20 _i to the set value X. Therefore, the displacement volume of the hydraulic motor 14 _{i + 1} may be adjusted based on the command value from the synchronizer 120. The setting value X is greater than the minimum load of the synchronous generator 20 _i, is less than the rated output of the synchronous generator 20 _i, for example, there is less than 50% to 100% of the rated output of the synchronous generator 20 _i May be.
In this way, after the i-th synchronous generator 20 _i is inserted, after waiting for the output to increase to the set value X larger than the minimum load, the preparation for the (i + 1) -th synchronous generator 20 _{i + 1} is prepared. By performing this, it is possible to reduce the number of generators used during low-load operation and improve the efficiency of the wind power generator 1 as a whole during low-load operation. In addition, by less than the rated output of the synchronous generator 20 _i the set value X, increase the margin of the output of the i-th synchronous generator 20 _i corresponding to the difference between the set value X as the rated output is secured, Excess pressure oil energy generated during synchronization of the (i + 1) th synchronous generator 20 _{i + 1} can be absorbed by an increase in displacement volume of the i-th hydraulic motor 14 _i (an increase in output of the i-th synchronous generator 20 _i ). Therefore, the (i + 1) th of the hydraulic motor _{14 i + 1} can concentrate on the VFO (i + 1) th synchronization generator _{20 i + 1,} to facilitate the synchronization adjustment is (i + 1) th synchronization generator _{20 i + 1.}

FIG. 8 is a diagram for explaining a state in which two synchronous generators 20 _k are inserted into the power system 50 in the above procedure.

First, when the start condition is satisfied when the wind speed measured by the anemometer 33 exceeds the cut-in wind speed at t = t ₀ , the actuator 5 shifts the pitch angle of the blade 4 to the fine side under the control of the pitch control unit 7. Thus, the aerodynamic energy input to the hydraulic pump 12 is increased. At this time, the displacement of the hydraulic pump 12 is set to zero by the pump control unit 44. As a result, the rotary shaft 8 is accelerated at an angular acceleration corresponding to the aerodynamic torque applied to the hydraulic pump 12.

When the rotational speed of the rotary shaft 8 reaches a predetermined value (for example, the rotational speed within a range of 40 to 60% of the rated rotational speed) at t = t ₁ , the displacement of the hydraulic pump 12 is increased by the pump control unit 44. , starting the discharge of the oil to the high pressure oil line 16, to increase the high-pressure oil pressure P _s which is measured by the oil pressure sensor 31. When the high pressure oil pressure P _s reaches the predetermined value, while maintaining the rotational speed of the rotary shaft 8 by the pitch angle adjustment of the blade 4 by the pitch control unit 7 to the target speed, displacement of the hydraulic pump 12 by the pump control unit 44 volume Is adjusted to maintain the high pressure oil pressure _Ps at the target pressure. When the rotational speed and high oil pressure P _s of the rotating shaft 8 is stabilized, by starting the first hydraulic motor 14 _1, the rotational speed of the hydraulic motor 14 ₁ is raised toward the rated speed w _rated. Note that when accelerating the hydraulic motor 14 _1, as described above, until it reaches a predetermined rotational speed w ₀ with priming valve 17 and the low-pressure valve 98, the high pressure valve 96 and a low pressure after reaching the predetermined rotational speed w ₀ with valve 98, may be adjusted displacement of the hydraulic motor 14 _1. When the hydraulic motor 14 ₁ reaches the predetermined rotational speed, starting the first synchronous generator 20 ₁ of excitation system. The motor control unit 48 to adjust the displacement volume of the hydraulic motor 14 ₁ in accordance with the command value from the synchronizer 120, the frequency difference and phase difference between the synchronous generator 20 ₁ side and the power grid 50 side within a predetermined range Fit. Further, by adjusting the field current exciter control unit 110 flows through the field winding 21 based on the control signal from the synchronizer 120, a predetermined voltage difference between the synchronous generator 20 ₁ side and the power grid 50 side Keep within range. Thus the frequency difference between the synchronous generator 20 ₁ side and the power grid 50 side, while the phase difference, and the voltage difference falls within the predetermined range, the synchronizer 120 sends a close signal to the circuit breaker 122, at time t ₂ synchronous generator 20 ₁ is the incorporation into the power grid 50.

After the synchronous generator 20 ₁ the incorporation, pitch control of the blades 4, the control of the hydraulic pump 12 and the hydraulic motor 14 ₁ shifts to the normal control mode described later. Specifically, the pitch controller 7 substantially fixes the pitch angle of the blade 4 on the fine side. Further, as will be described later with reference to FIG. 10, the displacement of the hydraulic pump 12 by the pump control unit 44 is adjusted so that the torque of the hydraulic pump 12 becomes a value corresponding to the rotational speed of the rotary shaft 8. Furthermore, as will be described later with reference to FIG. 12, performs modulation of the displacement hydraulic motor 14 ₁ by the motor control unit 48 so that the high pressure oil pressure P _s is maintained at the target pressure. Then, gradually increasing the displacement volume of the hydraulic pump 12 and the hydraulic motor 14 _1, gradually increasing the output of the synchronous generator 20 _1.

When increasing the displacement volume of the hydraulic motor 14 ₁ to the output of the synchronous generator 20 ₁ reaches the set value X, 2 th hydraulic motor 14 ₂ start at time t _3, the hydraulic motor 14 ₂ rpm Increase toward the rated speed w _rated . Note that when accelerating the hydraulic motor 14 _2, similarly to the hydraulic motor 14 _1, until it reaches a predetermined rotational speed w ₀ with priming valve 17 and the low-pressure valve 98, after reaching a predetermined rotational speed w ₀ is the high pressure valve 96 and using a low-pressure valve 98 may be adjusted displacement of the hydraulic motor 14 _2. When the hydraulic motor 14 ₂ reaches a predetermined rotational speed, starting the second synchronous generator 20 _{and second} excitation system. The motor control unit 48 in accordance with the command value from the synchronizer 120 is to adjust the displacement volume of the hydraulic motor 14 _2, the frequency difference and phase difference between the synchronous generator 20 ₂ side and the power grid 50 side within a predetermined range Fit. Further, by adjusting the field current exciter control unit 110 flows through the field winding 21 based on the control signal from the synchronizer 120, a predetermined voltage difference between the synchronous generator 20 ₂ side and the power grid 50 side Keep within range. Thus the frequency difference between the synchronous generator 20 ₂ side and the power grid 50 side, the phase difference, and in a state in which a voltage difference is within a predetermined range, synchronizer 120 sends a close signal to the circuit breaker 122, at time t ₄ synchronous generator 20 ₂ is the incorporation to the power system 50.

After the synchronous generator 20 ₂ the incorporation, to transfer control of the hydraulic motor 14 ₂ to the normal control mode. Specifically, as will be described later with reference to FIG. 12, performs modulation of the displacement hydraulic motor 14 ₂ by the motor control unit 48 so that the high pressure oil pressure P _s is maintained at the target pressure. Then, by increasing both the synchronous generator 20 ₁ and 20 ₂ of the output, the synchronous generator ₂₀ 1 at time _{t 5,} 20 _second output reaches the rated output. In other words, the rated output of the entire wind turbine generator 1 is obtained at time t _5.

If the wind speed decreases below the rated wind speed, the displacement of the hydraulic motors 14 ₁ , 14 ₂ is gradually reduced, and the output of the synchronous generators 20 ₁ , 20 ₂ is gradually reduced to reach the minimum load. Line up. At this time, the other synchronous generator 20 may be disconnected while maintaining the output of one synchronous generator 20 at the rated output. The order in which the synchronous generators 20 ₁ and 20 ₂ are disconnected may be determined based on the cumulative operating time of each set of the synchronous generator 20 _i and the hydraulic motor 14 _i , the number of times the circuit breakers 122 are opened and closed, and the like.
In the example shown in FIG. 8, the synchronous generator 20 ₁ is lowered output remains synchronous generator 20 ₂ and maintained at the rated output at least load, solutions of the alternator 20 ₂ opens the circuit breaker 122 at time t ₆ Line up. When the wind speed is further reduced, by gradually reducing the displacement volume of the hydraulic motor 14 _1, gradually reducing the output of the synchronous generator 20 _1. After lowering the output of the synchronous generator 20 ₁ to the lowest load and disconnecting the synchronous generator 20 ₁ Open circuit breaker 122 at time t _7.

Alternatively, after the i-th (where i is an arbitrary integer in the range of 1 to (N−1)) synchronous generator 20 _i is incorporated into the power system 50, the first to i-th synchronous generators 20 ₁ , ... (i + 1) th synchronous generator 20 _{i + 1} may be synchronized while maintaining the output of 20 _i at the minimum load. That is, after the i-th synchronous generator 20 _i enters the power system 50, the motor control unit 48 adjusts the displacement volume of the _i hydraulic motors 14 _{1 to} 14 _i to synchronize the generators 20 _{1 to} 20 _i. The synchronous generator 20 _{i + 1} may be synchronized by adjusting the displacement of the hydraulic motor 14 _{i + 1} on the basis of the command value from the synchronizer 120 while maintaining the output at the minimum load.
As a result, operation using all of the N sets of the synchronous generator 20 and the hydraulic motor 14 is performed except for an extremely low load operation region close to the cut-in wind speed that is the power generation start point of the wind turbine generator 1. Therefore, except for an extremely low load operation region close to the cut-in wind speed, each set of the synchronous generator 20 and the hydraulic motor 14 can be handled in the same manner, and simple operation control becomes possible. In addition, variations in the frequency of use of each set of the synchronous generator 20 and the hydraulic motor 14 can be reduced.

FIG. 9 is a diagram for explaining a state in which two synchronous generators 20 _k are inserted into the power system 50 in the above procedure.
The procedure until the _first synchronous generator 201 is inserted into the power system 50 (the procedure from t = t _{10 to} t ₁₂ ) is the same as the procedure from t = t _{0 to} t ₂ in FIG. Therefore, the description thereof is omitted here.

After the first of the synchronous generator 20 ₁ the incorporation, if the displacement volume of the hydraulic pump 12 and the hydraulic motor 14 ₁ is stabilized, when the output of the synchronous generator 20 ₁ is maintained at the minimum load, the second hydraulic motor start 14 _2, the rotational speed of the hydraulic motor 14 ₂ is increased towards the rated rotational speed _{w rated.} Note that when accelerating the hydraulic motor 14 _2, as described above, until it reaches a predetermined rotational speed w ₀ with priming valve 17 and the low-pressure valve 98, the high pressure valve 96 and a low pressure after reaching the predetermined rotational speed w ₀ with valve 98, may be adjusted displacement of the hydraulic motor 14 _2. When the hydraulic motor 14 ₂ reaches a predetermined rotational speed, starting the second synchronous generator 20 _{and second} excitation system. The motor control unit 48 in accordance with the command value from the synchronizer 120 is to adjust the displacement volume of the hydraulic motor 14 _2, the frequency difference and phase difference between the synchronous generator 20 ₂ side and the power grid 50 side within a predetermined range Fit. Further, by adjusting the field current exciter control unit 110 flows through the field winding 21 based on the control signal from the synchronizer 120, a predetermined voltage difference between the synchronous generator 20 ₂ side and the power grid 50 side Keep within range. Thus the frequency difference between the synchronous generator 20 ₂ side and the power grid 50 side, while the phase difference, and the voltage difference falls within the predetermined range, the synchronizer 120 sends a close signal to the circuit breaker 122, at time t ₁₃ synchronous generator 20 ₂ is the incorporation to the power system 50.

Thereafter, both the synchronous generator 20 ₁ and 20 ₂ by the output increased at the same load, each synchronous generator ₂₀ 1 at time _{t 14,} 20 ₂ of the output reaches the rated output. In other words, the rated output of the entire wind turbine generator 1 is obtained at time t _14.

If the wind speed decreases below the rated wind speed, the displacement of the hydraulic motors 14 ₁ , 14 ₂ is gradually reduced, and the output of the synchronous generators 20 ₁ , 20 ₂ is gradually reduced to reach the minimum load. Line up. At this time, the outputs of both the synchronous generators 20 ₁ and 20 ₂ may be simultaneously reduced at substantially the same rate toward the lowest load.
In the example shown in FIG. 9, the displacement volume of the hydraulic motors 14 ₁ and 14 ₂ is gradually reduced at substantially the same rate, and the outputs of the synchronous generators 20 ₁ and 20 ₂ are gradually reduced. Then, at time t _15, output first is paralleled the lowered synchronous generator 20 ₁ to the lowest load. At time t _16, delayed output is paralleled the lowered synchronous generator 20 ₂ to the lowest load.

In addition, when the synchronous generator 20 _i is sequentially turned on in the procedure described with reference to FIGS. 8 and 9, when the wind speed is continuously lower than the cut-in wind speed for a predetermined time, the synchronous power generation incorporated in the power system 50 is performed. All the machines 20 may be disconnected and the power generation by the wind power generator 1 may be stopped.

Further, when the rated output of the wind turbine generator 1 is set to “ _Prated” , the M synchronous generators 20 out of the N synchronous generators 20 (where M is an integer of 1 to (N−1)) are in failure. The wind power generator 1 may generate power at an output of P _rated × (N−M) / N or less. Thereby, even if some synchronous generators 20 break down, the partial load operation of the wind power generator 1 can be continued, and lost generation opportunities can be avoided.
The failure of the synchronous generator 20 may be detected by a monitoring device such as the terminal voltage detector 59, for example. The hydraulic motor 14 connected to the synchronous generator 20 in which the failure is detected is stopped by the motor control unit 48 with the displacement volume being zero, and the operation is continued while the remaining synchronous generator 20 is connected to the power system 50. May be.

  Furthermore, even when all of the synchronous generators 20 are disconnected, the power to be supplied to the auxiliary machine of the wind power generator 1 may be generated by the at least one synchronous generator 20.

[Normal control mode of transmission control unit]
The wind turbine generator 1 having the above configuration controls the hydraulic transmission 10 in a normal control mode described below during operation except before and after the synchronous generator 20 _k is inserted.

As shown in FIG. 2, the transmission control unit 40 includes an ideal torque calculation unit 41, a torque target calculation unit 42, a pump request value calculation unit 43, a pump control unit 44, a pump target output calculation unit 45, and a motor target output calculation unit 46. The motor request value calculation unit 47, the motor control unit 48, and the storage unit 49 are provided.
In the normal control mode, the transmission control unit 40 adjusts the displacement volume of the hydraulic pump 12 by the pump control unit 44 so that the torque of the hydraulic pump 12 becomes a value corresponding to the number of rotations of the rotary shaft 8, and the hydraulic motor 14. _k output target value based on pOWER _M adjusted by a motor control unit 48 the displacement of the hydraulic motor 14 _k as high oil pressure P _s is maintained at the target pressure. Therefore, variable speed operation in which the rotation speed of the rotary shaft 8 is variable with respect to the wind speed is possible without using a frequency conversion circuit, and output smoothing and power generation efficiency can be improved. Further, since the high pressure oil pressure P _s is maintained at the target pressure by adjusting the displacement volume of the hydraulic motor 14 _k , the operation control of the wind turbine generator 1 can be performed stably.

Hereinafter, the operation of each unit of the transmission control unit 40 in the normal control mode will be described. Since the role of the transmission control unit 40 is roughly divided into the control of the hydraulic pump 12 and the control of the hydraulic motor 14 _k , the control for adjusting the displacement of the hydraulic pump 12 will be described in detail here, and then the hydraulic motor It will be described in detail a control for adjusting the displacement volume of 14 _k.

FIG. 10 is a diagram illustrating a signal flow when the displacement volume of the hydraulic pump 12 is determined in the transmission control unit 40. As shown in the figure, the ideal torque calculator 41 receives the rotational speed W _r of the rotary shaft 8 detected by the rotational speed meter 32, and determines the ideal torque T _i of the hydraulic pump 12 from the rotational speed W _r. To do. For example, the ideal torque calculation unit 41 reads a preset W _r −T _i function (a function of the rotational speed W _r and the ideal torque T _i ) from the storage unit 49 (see FIG. 2), and the W _r −T An ideal torque T _i corresponding to the rotational speed W _r is obtained using the _i function.

Here, an example of a _W r -T _i function stored in the storage unit 49.
11, the horizontal axis of the rotor rotational speed W _r, is a graph showing the Cp maximum curve in the coordinate system on the vertical axis of the rotor torque T. The Cp maximum curve 300 is a curve connecting coordinates (W _r , T) that maximize the power coefficient Cp. The Cp maximum curve 300 is a curve that passes through the coordinates Z _{1 to} Z ₅ such that the power coefficient Cp becomes maximum for various wind speeds (for example, wind speeds V _{0 to} V ₅ ).
_W r -T _i functions stored in the storage unit 49, as shown by the bold line in FIG. 11, the range of operating points a~ operating point b is defined by Cp maximum curve 300, the operating point b~ operating point c In the range, the function 310 may be defined by a straight line in which the rotor rotational speed is constant at the rated rotational speed W _rated . The wind speed V ₀ corresponding to the operating point a is a cut-in wind speed, and the wind speed V ₄ corresponding to the operating point c is a wind speed (rated wind speed) that reaches the rated output. In order to determine the ideal torque T _i by the function 310, the rotor torque T (that is, the ideal torque T _i ) corresponding to the rotation speed W _r of the rotating shaft 8 detected by the rotation speed meter 32 may be obtained from the function 310.
By using the function 310, the wind speeds of cut-in wind speed _{V 0} ~ wind speed _{V 3,} ranging from the initial rotational speed _{W 0} of the rated speed _{W rated,} the rotation speed of the hydraulic pump 12 (the rotor rotational speed) _{W r} The operation can be performed under the condition that the power coefficient Cp is maximized by changing according to the wind speed. That is, the initial rotational speed W ₀ in the variable speed range of rated speed W _rated, and can be operated as maximum efficiency is obtained. Further, in the wind speed region of the wind speed V ₃ to the rated wind speed V ₄ , the rotation speed (rotor rotation speed) W _r of the hydraulic pump 12 is maintained at the rated rotation speed W _rated . In the high wind speed range from the rated wind speed V ₄ to the cut-out wind speed, the pitch angle of the blade 4 is adjusted by the actuator (pitch drive mechanism) 5 and maintained at the rated output.

The ideal torque T _i of the hydraulic pump 12 obtained in this way is corrected in the torque target calculation unit 42 as shown in FIG. 10, and the torque target T _d of the hydraulic pump 12 is obtained.
The torque target calculation unit 42 multiplies the ideal torque T _i by the scale factor M to calculate the adjusted ideal torque MT _i . The scale factor M may be any value as long as it is within the range of 0 to 1, and is preferably within the range of 0.9 to 1. By multiplying by the scale factor M, the actual torque of the hydraulic pump 12 becomes slightly lower than the ideal torque T _i , and the rotor 2 accelerates more rapidly during a gust of wind. As a result, a larger output can be obtained as compared with a case where the ideal torque T _i is not multiplied by the scale factor M. Note that when the scale factor M is used, the rotor 2 decelerates more slowly, so that the engine is operated slightly off the optimum operating point during drought. However, the additional output obtained by following the gust is greater than the output loss due to non-optimal operation during drought.

Further, the torque target T _d obtained by the torque target calculation unit 42 may be a difference between the adjustment ideal torque MT _i and the output value of the torque feedback controller 201. The torque feedback controller 201 calculates the estimated value _Taero of the aerodynamic torque from the current value of the torque target and the acceleration torque. The acceleration torque is obtained by multiplying the angular acceleration a _r of the rotor 2 and the rotational moment of inertia J of the rotor 2. The output value of the torque feedback controller 201 is a deviation T _excess between the estimated value of the aerodynamic torque and the adjusted ideal torque. The deviation is multiplied by a gain G to calculate a correction torque T _feedback . The gain G may be any value greater than or equal to zero. If the gain G is set to 0, the torque feedback controller 201 is invalidated.

Torque feedback controller 201 slightly with decreasing the torque target T _d by reducing the torque from the adjustment ideal torque MT _i during acceleration, when adding a torque to adjust the ideal torque MT _i torque target T _d slightly to deceleration By increasing, it responds to the acceleration and deceleration of the rotor 2. Thereby, the rotation shaft 8 can be accelerated and decelerated more quickly according to the change of the input energy from the wind, compared with the case of controlling only the adjustment ideal torque. Therefore, the total amount of energy that can be recovered from the wind increases.

The torque target T _d determined by the torque target calculation unit 42 is sent to the pump requirement value calculating section 43, is used to calculate a required value D _P of displacement of the hydraulic pump 12. In target torque calculating section 42, divided by the pressure P _s of the hydraulic oil in the high pressure oil line 16, to calculate a required value D _p of displacement of the hydraulic pump 12. The demand value D _p may output values be PID-type controller may be corrected by the pressure limiter 202 is a request value D _p of the controller. The pressure limiter 202 maintains the pressure of the high pressure oil line 16 within an allowable range. That is, by correcting the amount of hydraulic oil movement required by the pump, the pressure of the high-pressure oil line 16 is maintained below the maximum level at which safe operation of the wind turbine generator is possible. In operating modes where it is desirable to dissipate energy through the relief valve 62 (for example, to prevent the wind turbine from operating above its rated speed during extreme gusts), the pressure limit may be disabled. Alternatively, the pressure limit value may vary depending on the application. Incidentally, in the pump requirement value calculating section 43, based on the temperature of the hydraulic fluid of the high pressure oil line 16, the demand value D _P of displacement of the hydraulic pump 12 may be corrected.

The pump request value calculation unit 43 corrects the torque target _Td of the hydraulic pump 12 by the adjuster 203 according to a power request signal from an external command station such as a wind farm farm control device or a power supply command station. May be. As a result, it is possible to obtain a power generation amount commensurate with a request from an external command station.

Thus the demand value D _P of the resulting displacement and sent to the pump control unit 44, displacement of the hydraulic pump 12 is adjusted to the required value D _P by the pump control unit 44. For example, the pump control unit 44 requests the displacement volume of the hydraulic pump 12 by controlling the opening and closing of the high pressure valve 86 and the low pressure valve 88 to change the ratio of the number of active chambers 83 to the total number of working chambers. it may be adjusted to a value D _P.

FIG. 12 is a diagram illustrating a signal flow when the displacement volume of the hydraulic motor 14 _k is determined in the transmission control unit 40. As shown in the figure, the pump target output calculation unit 45 adds the rotational speed W _r of the rotary shaft 8 acquired by the rotational speed meter 32 to the torque target T _d of the hydraulic pump 12 obtained by the torque target calculation unit 42. The base value POWER ₀ of the target output of the hydraulic pump 12 is calculated by multiplication. The pump target output calculating unit 45, in response to the power request signal S _d from the external control center 210 etc. farm control system and dispatching center, to calculate the output correction value POWER _C in adjuster 212. Then, the output correction value POWER _C is added to the previously obtained target output base value POWER ₀ to determine the target output POWER _P of the hydraulic pump 12.

The motor target output calculation unit 46 processes the target output POWER _P of the hydraulic pump 12 using a primary low-pass filter (transfer function H (s) = 1 / (T · s + 1)), and the motor target output POWER _M of the hydraulic motor 14 _k. Is calculated.
Next, the motor request value calculation unit 47 calculates the motor target output POWER _M by the high-pressure oil pressure P _s measured by the hydraulic sensor 31 and the rotational speed W _m of the hydraulic motor 14 _k measured by the rotational speed meter 36. By dividing, the nominal required value D _n of the displacement volume of the hydraulic motor 14 _k is _obtained .

Further, in the motor required value calculating unit 47 calculates the required correction values _{D b} from the motor target output POWER _M, the required value _{D m} of the displacement of the hydraulic motor 14 _k by adding the nominal required value _{D n} of the above Ask. This request correction value D _b is, for example, as shown in FIG. 12, a pressure feedback controller for multiplying the target pressure P _d of the high pressure oil line 16, a variable gain K _P the deviation between the pressure gauge 31 of the measuring values P _s You may obtain | require by 220.

The target pressure _Pd of the high-pressure oil line 16 may be obtained by inputting the current motor target output POWER _M to a function 230 of a preset motor target output and the target pressure of the high-pressure oil line 16. Note that the function 230 is at least partially defined by a curve such that the target pressure of the high pressure oil line 16 monotonously increases as the motor target output increases. Therefore, the target pressure of the high pressure oil line 16 when the motor target output is small (that is, the discharge amount of the hydraulic pump 12 is small) as compared with the case where the motor target output is large (that is, the discharge amount of the hydraulic pump 12 is large). P _d is set to a small value. Thereby, the internal leakage amount of the hydraulic oil with respect to the discharge amount of the hydraulic pump 12 when the motor target output is small can be reduced, and the influence of the internal leakage of the hydraulic oil on the control of the hydraulic transmission 10 can be suppressed.

Further, the variable gain K _P is obtained by using the function 232, the current value of the pressure of the high-pressure oil line 16 (measured value of the pressure gauge 31) P _s , the maximum value P _max in the allowable range of the pressure of the high-pressure oil line 16, It is determined according to the value P _min . For example, the function 230 sets the variable gain K _P to the maximum value K _max when the current pressure value P _s is outside the allowable range (ie, P _s <P _min or P _s > P _max ), When the current value P _s is within the allowable range (that is, P _min ≦ P _s ≦ P _max ), the variable gain K _P is increased toward the maximum value K _max as it approaches the minimum value P _min or the maximum value P _max. You may let them. Thus, when the case pressure P _s is about to deviate from the allowable range, or the pressure P _s is out of the allowable range, multiplied by the difference between the pressure P _s and the target pressure P _d of the high pressure oil line 16 The variable gain K _P can be increased (or set to the maximum value K _max ) to quickly bring the pressure P _s of the high pressure oil line 16 within an allowable range and approach the target pressure P _d .

Note that the terminal voltage of the synchronous generator 20 _k is kept constant by controlling the exciter 100 by the exciter controller 110. For example, as shown in FIG. 6, in the comparison circuit 113, a deviation between a measured value of the terminal voltage of the synchronous generator 20 _k by the terminal voltage detector 59 and a set value input from the synchronizer 120 is obtained. The gate signal of the thyristor 116 may be supplied from the AVR 114 based on the above. Thereby, the magnitude of the field current supplied to the field winding 21 of the synchronous generator 20 _k is adjusted, and the terminal voltage of the synchronous generator 20 _k is maintained at the system voltage.

As described above, in the present embodiment, the synchronizer 120 is configured so that the frequency and phase of the terminal voltage of each synchronous generator 20 _k are synchronized with the power system 50 before the synchronous generators 20 _k are inserted. A command value for the displacement volume of the hydraulic motor 14 _k is given to the motor control unit 48. Therefore, even if a frequency conversion circuit is not interposed between each synchronous generator 20 _k and the power system 50, the synchronous generator 20 _k can be inserted into the power system 50 without depending on the frequency conversion circuit. Can be produced by the synchronizer 120.
Further, since the displacement of the plurality of hydraulic motors 14 _k by the motor control unit 48 is adjusted independently of each other, any combination of the plurality of sets of synchronous generators 20 _k and hydraulic motors 14 _k used for operation is arbitrarily selected. Can be selected. Therefore, operation can be performed using only a partial set of the synchronous generator 20 _k and the hydraulic motor 14 _k as necessary. For example, in order to improve the efficiency of the wind power generator 1 as a whole during low-load operation, the number of sets used for the operation of the synchronous generator 20 _k and the hydraulic motor 14 _k is reduced, or the synchronous generator 20 _k and the hydraulic motor 14 are reduced. Power generation can be continued using a set of the synchronous generator 20 _k and the hydraulic motor 14 _k that are not in failure in order to avoid the lost opportunity of power generation at the time of failure of _k .

Further, since the wind turbine generator 1 employs the hydraulic transmission 10 as a drive train that transmits power from the rotor 2 to the generator 20 _k , the generator shaft (the output shaft 15 of the hydraulic motor 14 _k ) is separated from the rotating shaft 8. ing. For this reason, it is easy to divide the power from the rotating shaft 8 into a plurality of generators 20 _{k and} to input them to the generator 20 _k, and the wind power generator 1 provided with the plurality of generators 20 _k can be realized with a simple configuration.
Then, by providing a plurality of generators 20 _k, as compared to a wind power generator using only a single generator, thereby improving the fault tolerance and power generation opportunities generator 20 _k, efficiency at low load operation Can be improved. In particular, the synchronous generator 20 _{k including the} exciter 100 as in the example shown in FIG. 6 is known to be inferior in efficiency at a low load as compared with the permanent magnet synchronous generator. By providing a plurality of synchronous generators 20 _k having a configuration, it is possible to enjoy a great effect of efficiency improvement during low-load operation.

  As mentioned above, although embodiment of this invention was described in detail, it cannot be overemphasized that this invention is not limited to this, In the range which does not deviate from the summary of this invention, various improvement and deformation | transformation may be performed.

DESCRIPTION OF SYMBOLS 1 Wind power generator 2 Rotor 4 Blade 5 Actuator 6 Hub 7 Pitch control part 8 Rotating shaft 10 Hydraulic transmission 12 Hydraulic pump 14 Hydraulic motor 15 Output shaft 16 High pressure oil line 17 Start valve 18 Low pressure oil line 20 Synchronous generator 21 Field winding Line 22 Nacelle 24 Tower 31 Pressure gauge 32 Revolution meter 33 Anemometer 34 Atmospheric temperature sensor 36 Revolution meter 40 Transmission control unit 41 Ideal torque calculation unit 42 Torque target calculation unit 43 Pump requirement value calculation unit 44 Pump control unit 45 Pump target Output calculation unit 46 Motor target output calculation unit 47 Motor required value calculation unit 48 Motor control unit 49 Storage unit 50 Power system 59 Terminal voltage detector 60 Bypass flow path 62 Relief valve 64 Accumulator 66 Electromagnetic valve 70 Oil tank 72 Replenishment In 74 boost pump 76 Oil filter 78 return line 79 low-pressure relief valve 100 exciter (AC exciter)
DESCRIPTION OF SYMBOLS 102 Field winding 103 Rotary rectifier 106 Permanent magnet generator 110 Exciter control part 113 Comparison circuit 114 Automatic voltage regulator (AVR)
116 Thyristor 120 Synchronizer 122 Circuit breaker 124 Terminal voltage detector 126 System voltage detector 201 Torque feedback controller 202 Pressure limiter 203 Adjuster 210 External command center 212 Adjuster 220 Pressure feedback controller 300 Cp maximum curve 310 W _r -T _i function 500 Increase Speed machine 520 Secondary winding induction generator 530 AC-DC-AC converter (frequency conversion circuit)
540 Synchronous generator 550 AC-DC-AC link (frequency conversion circuit)

Claims (15)

A regenerative energy generator that generates electric power using renewable energy,
The blade,
A rotating shaft that is rotated by the regenerative energy received via the blade;
A hydraulic pump that is driven by the rotating shaft to generate pressure oil;
A plurality of hydraulic motors driven by the pressure oil;
A plurality of synchronous generators connected to the power system without going through a frequency conversion circuit and respectively connected to the plurality of hydraulic motors;
A motor controller that adjusts the displacement of the plurality of hydraulic motors independently of each other;
Before inserting each synchronous generator into the electric power system, the motor control unit sets the command value of the displacement volume of each hydraulic motor so that the frequency and phase of the terminal voltage of each synchronous generator are synchronized with the electric power system. A regenerative energy type power generator comprising: a synchronizer for feeding to a power source.   The motor control unit is configured to displace the hydraulic motor so that the pressure of the hydraulic oil is maintained at a target pressure based on an output target value of each hydraulic motor after the synchronous generator is inserted into the power system. The regenerative energy type power generator according to claim 1, wherein Each of the synchronous generator and the hydraulic motor is provided with N pieces (where N is an integer of 2 or more),
The N synchronous generators are sequentially inserted into the power system according to an increase in the flow rate of the renewable energy,
The said motor control part adjusts the displacement volume of each hydraulic motor based on the said command value from the said synchronizer before joining to the said electric power grid | system of each synchronous generator. Renewable energy generator. The motor controller is
After the i-th (N is an arbitrary integer in the range of 1 to (N-1)) synchronous generator of the N pieces, the output of the i-th synchronous generator is After increasing the displacement volume of the i-th hydraulic motor connected to the i-th synchronous generator until reaching a set value that is larger than the minimum load of the synchronous generator and smaller than the rated output of the synchronous generator,
Before the (i + 1) th synchronous generator among the N units is incorporated into the power system, the (i + 1) th synchronous generator is connected to the (i + 1) th synchronous generator based on the command value from the synchronizer (i + 1). The regenerative energy type power generator according to claim 3, wherein a displacement volume of the () th hydraulic motor is adjusted.   The regenerative energy generator according to claim 3, wherein the set value is 50% or more and less than 100% of a rated output of the i-th synchronous generator.   The motor control unit is the first to i-th after the i-th (N is an arbitrary integer in the range of 1 to (N-1)) synchronous generator of the N power generators. The displacements of the first to i-th hydraulic motors are adjusted so that the outputs of the i-th synchronous generators are maintained at the minimum load, and the (i + 1) -th of the N synchronous generators Before displacement into the power system, the displacement of the (i + 1) th hydraulic motor connected to the (i + 1) th synchronous generator is adjusted based on the command value from the synchronizer. The regenerative energy type power generator according to claim 3. A pitch controller for adjusting the pitch angle of the blade;
A pump control unit for adjusting a displacement volume of the hydraulic pump;
The pitch angle of the blade is adjusted by the pitch controller so that the rotational speed of the rotary shaft is maintained at a target rotational speed before the first of the N synchronous generators enters the power system. The displacement of the hydraulic pump is adjusted by the pump control unit so that the pressure oil pressure is maintained at a target pressure, and the motor control unit is based on the command value from the synchronizer. The regenerative energy generator according to claim 3, wherein the displacement of the first hydraulic motor connected to the first synchronous generator is adjusted.   Based on at least one of the cumulative operating time of each set of the synchronous generator and the hydraulic motor, and the number of switching times of each circuit breaker that switches the connection state between each synchronous generator and the power system, the synchronous generator The regenerative energy type power generator according to claim 3, wherein the order of insertion is determined. A pump control unit for adjusting a displacement volume of the hydraulic pump;
After the i-th (N is an arbitrary integer in the range of 1 to (N-1)) synchronous generator of the N pieces, the output of the i-th synchronous generator gradually increases. The displacement of the hydraulic pump is adjusted by the pump controller, and the displacement of the i-th hydraulic motor connected to the i-th synchronous generator is adjusted by the motor controller. The regenerative energy type power generator according to claim 3. When the rated output of the renewable energy power generating device and _{P rated,} the N of the M (where M is one or more (N-1) an integer) of the _{P rated} × when the synchronous generator failure (N The renewable energy type power generator according to claim 3, wherein power is generated at an output of -M) / N or less.   When the flow rate of the regenerative energy is lower than the cut-in flow rate that is the power generation start point of the regenerative energy type power generation device, all the synchronous generators that are incorporated in the power system are disconnected, and the regenerative energy type The regenerative energy power generator according to claim 1, wherein power generation of the power generator is stopped.   2. The power generation apparatus according to claim 1, wherein when all of the synchronous generators are disconnected, the electric power to be supplied to an auxiliary machine of the renewable energy power generation apparatus is generated by at least one of the synchronous generators. Renewable energy generator. Each hydraulic motor includes a plurality of working chambers surrounded by cylinders and pistons, a plurality of high pressure valves that supply the pressure oil to the working chambers, and a plurality of low pressures that discharge the pressure oil from the working chambers. A valve, and a casing in which the working chamber, the high-pressure valve, and the low-pressure valve are housed,
Further provided with a start valve provided outside the casing corresponding to each hydraulic motor,
When each hydraulic motor is started, the motor control unit adjusts the number of the working chambers in which the pressure oil is supplied and discharged by opening / closing control of the start valve and the low pressure valve, and sets each hydraulic motor to a valve switching target. Accelerate to the number of revolutions, adjust the number of working chambers to which the pressure oil is supplied and discharged by opening / closing control of the high-pressure valve and the low-pressure valve to further exceed each valve motor switching target revolution number The regenerative energy power generation device according to claim 1, which is accelerated.   The renewable energy type power generator according to claim 1, wherein the renewable energy type power generator is a wind power generator that generates electric power from wind as the renewable energy. A rotating shaft that is rotated by regenerative energy received via a blade; a hydraulic pump that is driven by the rotating shaft to generate pressure oil; a plurality of hydraulic motors that are driven by the pressure oil; and the plurality of hydraulic motors A method for operating a regenerative energy type power generation device comprising a plurality of synchronous generators connected to each other,
Adjusting the displacement volumes of the plurality of hydraulic motors independently from each other based on a command value from the synchronizer so that the frequency and phase of the terminal voltage of each synchronous generator are synchronized with the power system;
After the step of adjusting the displacement volume, a step of inserting the plurality of synchronous generators into the power system without going through a frequency conversion circuit is provided.

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