JP7209542B2 - Wind power generator and its operation method - Google Patents

Description

The present invention relates to a wind power generator and its operating method, and more particularly to a wind power generator and its operating method that monitors the wind power generator and performs degeneration operation according to the degree of deterioration.

Due to growing interest in the use of renewable energy, the global market for wind power generators is expected to expand. As a megawatt class wind power generator, it has a rotor with blades attached radially to a rotating hub, a nacelle that supports the rotor via the main shaft, and a tower that supports the nacelle from below while allowing yaw rotation. is frequently used.

A wind power generator generates power using wind that changes every second as an energy source. Therefore, if the wind speed and turbulence of the wind that actually flows into the wind turbine generator are more severe than the design conditions, the load on the wind turbine generator increases, possibly accelerating damage to the components. If an unexpected failure occurs due to accelerated damage, in addition to the time required to replace the failed part, it will take time to arrange replacement parts, construction equipment, and workers. There is a concern that the operation stop time of the wind power generator will increase and the amount of power generation will decrease compared to the case of implementing

As a countermeasure, there is a method of estimating the damage to the components of the wind power generator, and reducing the load by degenerate operation such as reducing the rated output when the damage accelerates. For example, in Patent Document 1, when the fatigue damage exceeds a threshold calculated from the service life, the cutout wind speed, which is the maximum wind speed at which the wind power generator operates, is changed to reduce the amount of power generation. There have been proposed methods of prolonging life by performing

Patent No. 5244502

However, if the rated output or cutout wind speed is changed to prolong the life, there is a concern that the amount of power generated during the degeneracy operation will drop significantly. This is because the wind speed range in which degenerate operation is performed does not match the wind speed range in which damage is likely to be accelerated, and degenerate operation is applied even at wind speeds in which damage is not accelerated.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a wind power generator that maximizes the amount of power generated during degenerate operation and a method of operating the same.

From the above, in the present invention, "a wind power generator having at least a rotor, a nacelle, and a tower for supporting the nacelle, and performing degeneration operation by a control device, wherein the control device controls the degree of damage per generated power against the wind speed is determined, and degeneration operation is performed when the degree of damage per generated power determined exceeds a specified value.

In addition, in the present invention, "a wind power generation method for a wind turbine generator having at least a rotor, a nacelle, and a tower for supporting the nacelle and performing degenerate operation, wherein the A method of operating a wind turbine generator characterized in that the amount of feather operation of the pitch angle is increased more than in a normal operation in which no degeneracy operation is performed.

According to the present invention, by changing the control amount based on the degree of damage per generated power, it is possible to maximize the amount of power generated during the degeneracy operation.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram showing an example of an overall schematic configuration of a wind power generator that is a premise of the present invention; The figure which shows the structural example of the wind turbine generator which concerns on Example 1 of this invention. FIG. 2 is a diagram for explaining a control device and a controlled object in the first embodiment; FIG. A diagram for explaining the relationship between the average wind speed and the degree of damage per generated power. FIG. 4 is a diagram for explaining a case where the degree of damage per generated power has a plurality of maximum values; FIG. 8 is a diagram for explaining a control device and a controlled object in Embodiment 2; FIG. 5 is a diagram showing a state in which the power curve, damage degree, and damage degree per generated power in FIG. 4 are corrected during degenerate operation; FIG. 5 is a diagram for explaining an ideal control amount using the degree of damage per generated power; FIG. 5 is a diagram for explaining a degeneracy operation method by increasing the feather control amount of the pitch angle; FIG. 5 is a diagram for explaining a degeneracy operation method using a stepped power curve based on wind speed; FIG. 5 is a diagram for explaining a degeneracy operation method using a concave power curve based on wind speed; FIG. 4 is a diagram for explaining the difference between degeneracy operation based on the degree of damage per generated power and conventional degeneracy operation. FIG. 4 is a diagram for explaining a degenerate operation method by increasing the number of revolutions of a generator;

Hereinafter, the embodiments of the present invention will be described with reference to the drawings, and the wind turbine generator as a premise thereof is generally configured as follows.

FIG. 1 is a diagram showing an example of an overall schematic configuration of a wind power generator that is a premise of the present invention. As shown in FIG. 1, the wind turbine generator 1 includes blades 2 that rotate with wind, a hub 3 that supports the blades 2, a nacelle 4, and a tower 5 that rotatably supports the nacelle 4. As shown in FIG.

Inside the nacelle 4 are a main shaft 6 that is connected to the hub 3 and rotates together with the hub 3, a gearbox 7 that is connected to the main shaft 6 and increases the rotational speed, and a rotor whose rotational speed is increased by the gearbox 7. is provided with a generator 8 that rotates to generate power. A portion that transmits the rotational energy of the blades 2 to the generator 8 is called a power transmission section, and in this embodiment, the main shaft 6 and the gearbox 7 are included in the power transmission section. The gearbox 7 and generator 8 are held on the main frame 9 . A rotor 10 is composed of the blades 2 and the hub 3 .

As shown in FIG. 1, at the bottom (lower part) in the tower 5, there are a power converter 11 for converting the frequency of power, a switching switch and a transformer for switching current (not shown), and a control A device 12 and the like are arranged. As the control device 12, for example, a control panel or SCADA (Supervisory Control And Data Acquisition) is used.

Although the wind turbine generator 1 shown in FIG. 1 shows an example in which the rotor 10 is composed of three blades 2 and a hub 3, it is not limited to this, and the rotor 10 consists of a hub 3 and at least one blade 2. You can configure

Basically, the present invention monitors the wind power generator configured as shown in FIG. 1 and executes degeneration operation according to the degree of deterioration. For this purpose, an anemometer 23 and a strain sensor 24 are further provided, and the generator 8, the pitch angle control mechanism 21, the yaw control mechanism 22, etc. are operated as controlled objects (operating ends) for the retraction operation.

FIG. 2 shows the wind turbine generator 1 viewed from the side, and the wind blows from left to right on the paper surface. Although FIG. 2 shows a downwind type wind power generator in which the rotor 10 is positioned on the leeward side of the tower 5, it may be an upwind type wind power generator in which the rotor 10 is positioned on the windward side of the tower 5. .

The wind turbine generator 1 includes a generator 8 capable of controlling the rotation speed, a pitch angle control mechanism 21 for controlling the pitch angle of the blades 2, a yaw control mechanism 22 for controlling the azimuth angle of the nacelle 4, and the It has an anemometer 23 installed on the top. The anemometer 23 may be installed at another position of the wind turbine generator 1 or may be installed outside the wind turbine generator 1 as long as it is in the vicinity of the wind turbine generator 1 .

The wind turbine generator 1 may also include strain sensors 24 attached to the blades 2 . The strain sensor 24 may be installed not only on the blade 2 but also on the tower 5, the nacelle 4, or the hub 3, or another load sensor such as an acceleration sensor may be used. Also, instead of the load sensor, a software sensor that estimates the load by numerical simulation based on the value of the anemometer 23 may be used.

FIG. 3 shows a configuration example of the control device 12 and the controlled object 30 of the wind turbine generator 1 according to the first embodiment for maximizing the power generation amount during the degeneracy operation.

The control device 12 of FIG. 3 is configured by a computer system, and functionally speaking, the processing content thereof is provided with an air velocity measurement unit 31, a load measurement unit 32, a damage degree calculation unit 33, and a control amount calculation unit 37. It can be said that For the processing, the computer system also includes damage degree data D1 held in the damage degree database DB1, power curve data D2 held in the power curve database DB2, and operation plan data D3 held in the operation plan database DB3. to use.

When using the damage degree database DB1 created in advance, the wind speed measurement unit 31, the load measurement unit 32, and the damage degree calculation unit 33 may be omitted. Further, the operation plan database DB3 does not need to be stored in the control device 12, and data in an external data center or operation center may be used.

The wind speed measurement unit 31 measures the wind speed using the anemometer 23 in FIG. 2, and outputs the average wind speed averaged over a predetermined period of time. In the averaging process, for example, the average wind speed is calculated every 10 minutes.

The load measurement unit 32 measures the strain and load of the blade 2 using the strain sensor 24 and the like. As an alternative to the strain sensor 24, another load sensor such as an acceleration sensor may be used. Also, instead of the load sensor, a software sensor that estimates the load by numerical simulation based on the value of the anemometer 23 may be used. In short, any device that can measure or estimate the strain and load that the blades 2 of the wind turbine generator 1 receive from the wind may be used.

The damage degree calculator 33 converts the strain and load time series data obtained by the load measurement unit 32 into stress at an arbitrarily designated monitoring target position using the elastic modulus and section modulus, and converts the stress time series data. For example, the rainflow method and the linear accumulation damage law are used to convert to the degree of fatigue damage every predetermined time. Other methods may be used to convert the time-series data of strain and load into the degree of damage, or the time-series data may be converted into a power spectrum and converted into the degree of damage. Also, the cumulative damage degree of the monitoring target position is calculated by accumulating the damage degree in a predetermined time. It is desirable that the monitoring target positions be a plurality of positions. Further, in the present invention, unless otherwise specified, the degree of damage is explained as a concept including the degree of deterioration.

In the damage degree database DB1, the relationship between the average wind speed for a predetermined time obtained by the wind speed measurement unit 31 and the damage degree obtained by the damage degree calculation unit 33 is stored as damage degree data D1 (damage degree distribution). When storing, all the data at each predetermined time may be stored as they are, or the average degree of damage with respect to the average wind speed may be stored as a statistical value.

The power curve database DB2 stores the relationship between wind speed and generated power in the wind turbine generator 1 as power curve data D2.

In the operation plan database DB3, the maintenance date of the position to be monitored and the permissible value of the accumulated damage degree up to that date are stored as the operation plan data D3. Note that instead of the allowable value up to the maintenance date, the allowable value of the accumulated damage degree as the life of the component may be stored.

The control amount calculator 37 first calculates an average damage degree distribution with respect to the average wind speed in a predetermined time from the data in the damage degree database DB1. For the average damage degree distribution, the average value of the damage degree may be obtained by dividing the wind speed into bins, or a regression model generated by polynomial expression, response surface method, or machine learning may be used. Next, the control amount calculator 37 takes the ratio of the average damage degree distribution and the generated power obtained from the power curve data D2, and calculates the degree of damage per generated power.

FIG. 4 is a diagram showing the relationship between the power curve, the degree of damage, and the degree of damage per generated power, which are the main elements in the control device 12 of FIG. 3, with the horizontal axis representing the average wind speed.

The upper part of FIG. 4 is the power curve data D2 held in the power curve database DB2. As shown by the average wind speed on the horizontal axis and the generated power on the vertical axis, the generated power increases according to the wind speed up to the rated wind speed. , the rated generated power is kept constant after the rated wind speed.

The middle part of FIG. 4 shows the damage degree data D1 (damage degree distribution) held in the damage degree database DB1. It becomes maximum near the wind speed, and shows a lower value as it moves away from near the rated wind speed.

The lower part of FIG. 4 shows the degree of damage per generated power obtained by the control amount calculation unit 37. As shown by the average wind speed on the horizontal axis and the degree of damage per generated power on the vertical axis, in this example, the degree of damage per generated power is maximum near the rated wind speed, but the trend in the region away from the rated wind speed shows different tendencies above and below the average wind speed. Although FIG. 4 shows an example in which the degree of damage is maximized near the rated wind speed, since the distribution of damage degree changes depending on the monitored object and position, the applicable object is limited to the state shown in FIG. is not.

The control amount calculator 37 of FIG. 3 calculates the degree of damage per generated power by the above method, but the control based on the calculated degree of damage per generated power is not always executed. Control based on the degree of damage per generated power is activated for the first time when the threshold is exceeded, and is performed only in the wind speed range exceeding the threshold.

In the vicinity of the wind speed at which the degree of damage per generated power obtained in this manner is maximized, the degenerate operation is performed by changing the controlled variables of the related controlled objects 30 such as the generator 8, the pitch control mechanism 21, and the yaw control mechanism 22. Control variables include, for example, rotor rotation speed, generator rotation speed, torque, pitch angle, and yaw angle. A value defined in advance may be used, or a method of a second embodiment described later may be used to determine the wind speed range in which the control amount and the control are changed during degenerate operation.

Further, when the degree of damage per generated power has a plurality of maximum values as shown in FIG. 5, the control amount may be changed in a plurality of wind speed ranges. The execution of the degeneracy operation may be determined by the driver, or may be automatically determined based on the cumulative damage degree of the monitoring target position and the allowable value of the cumulative damage degree of the operation plan data D3. good too.

Since there are several ideas for managing the degree of damage to a wind power generator, it is preferable to apply the method to actual control appropriately according to the method of managing the degree of damage. For example, as a damage management method, in daily life, the concept of applying control so as not to exceed the assumed maximum damage, the concept of complying with the cumulative damage within a certain period, or the concept of operating according to the management target of the amount of damage. However, the timing for starting control can be appropriately adopted in accordance with these ideas. The operation plan database DB3 in FIG. 3 preferably holds information on these management guidelines.

By using the control device 12 of the wind turbine generator 1 having the above configuration, according to the first embodiment, it is possible to specify the applicable wind speed for the degeneracy operation that can maximize the power generation amount during the degeneracy operation.

In a second embodiment, a method of determining a wind speed range for changing the control amount and control in the degenerate operation at the wind speed at which the degree of damage per generated power is maximized as specified in the first embodiment will be described.

FIG. 6 shows a configuration example of the control device 12 and the controlled object 30 of the wind turbine generator 1 according to the second embodiment. In the second embodiment, a control amount measuring unit 41 and a wind condition prediction database DB4 are additionally installed in the control device 12 of the first embodiment. In addition, in the embodiment of FIG. 6, the database configured with the information of the added control amount measuring unit 41 taken into account and its data are represented by DB1a, DB2a and D1a, D2a, so that the database DB1 of the first embodiment , DB2 and its data D1 and D2.

The controlled variable measurement unit 41 in FIG. 6 measures the controlled variable or the control target value in the controlled object 30 . In the damage degree database DB1a of the second embodiment, average values or target values of various control variables are stored in addition to the average wind speed and damage degree at a predetermined time. Control variables include, for example, rotor rotation speed, generator rotation speed, torque, pitch angle, yaw error, and generator output. At the time of saving, all the data at each predetermined time may be saved as they are, or the average degree of damage with respect to the average wind speed and various control variables may be saved as statistical values.

In the power curve database DB2a, in addition to the relationship between wind speed and generated power in the wind turbine generator 1, average values or target values of various control variables are stored. Control variables include, for example, rotor rotation speed, generator rotation speed, torque, pitch angle, and yaw error. At the time of saving, all the data at each predetermined time may be saved as it is, but it is desirable to use the average value of the generated power for the average wind speed and various control variables at the predetermined time.

The wind condition prediction database DB4 stores the wind speed frequency distribution in the wind turbine generator 1 as wind condition prediction data D4. The wind speed frequency distribution D4 may be created from the measured values acquired by the wind speed measurement unit 31, or may be created using data created in advance or the results of weather forecasts based on numerical simulations. Moreover, the creation period of the wind speed frequency distribution does not matter, for example, it may be created monthly, or a single frequency distribution may be used for the year.

The control amount calculation unit 37a of the second embodiment first calculates an average damage degree distribution with respect to the average wind speed and the control amount in a predetermined time from the damage degree data D1a of the damage degree database DB1a. For the average damage distribution, wind speeds and controlled variables may be divided into bins to determine the average value of damage, or a regression model generated by polynomial, response surface method, or machine learning may be used. Next, the control amount calculator 37a takes the ratio of the average damage degree distribution and the generated power obtained from the power curve data D2a for each control amount, and calculates the damage degree per generated power for each control amount.

FIG. 7 shows the relationship between the power curve in FIG. 4, the degree of damage, and the degree of damage per generated power. 7 shows the power curve (upper part of FIG. 7), the degree of damage (middle part of FIG. 7), and the degree of damage per generated power (lower part of FIG. 7).

Each value indicated by a solid line in the illustration of FIG. 7 is a value during normal operation, which is the same as in FIG. Each value indicated by is the value at the time of severe degeneracy operation (the amount of control is large).

FIG. 8 is a diagram for explaining the ideal control amount using the degree of damage per generated power, and the wind speed range in which the control amount and control are changed so as to smooth the vicinity of the maximum value of the degree of damage per generated power is shown. FIG. 7 shows a case where the control amount is changed while the wind speed range for changing the control is constant, but the wind speed range may be changed together. In order to maximize the amount of power generated during degenerate operation, it is desirable to adjust the control amount and the wind speed range in which the control is changed so as to smooth the vicinity of the maximum value of the degree of damage per generated power as shown in FIG. , the distribution shown in FIG. 8 is not necessarily required during degenerate operation due to restrictions on the control side.

As shown in FIGS. 7 and 8, the distribution of the degree of damage per generated power changes depending on the magnitude of the control amount and the wind speed range in which the control is changed. When maximizing the amount of power generated during degeneracy operation, the degree of these magnitudes is obtained by summing the damage degree obtained by the inner product of the wind speed frequency distribution and the damage degree distribution during the degeneracy operation period and the cumulative damage degree up to now. It is sufficient to set the estimated cumulative damage degree to match the allowable value of the cumulative damage degree of the operation plan database DB3. The wind speed frequency distribution during the degeneracy operation period can be estimated using the wind condition prediction database DB4 from the start of degeneracy operation to the maintenance date of the operation plan database DB3. However, since an error may occur in the estimated wind speed frequency distribution, the control amount and wind speed range of the degenerate operation are considered so that the estimated cumulative damage level is less than the allowable value of the cumulative damage level of the operation plan database DB3. can be set as

By using the control device 12 of the wind power generator 1 having the above configuration, according to the second embodiment, it is possible to appropriately determine the control amount and the wind speed range for the degeneracy operation, and the maximum power generation amount during the degeneracy operation. becomes possible.

In a third embodiment, a specific example of a degeneracy operation method using the wind speed range for changing the control amount and control identified in the second embodiment at the applicable wind speed for the degeneracy operation identified in the first embodiment will be described. However, it is not always necessary to use the degeneracy operation method described here, and degeneracy operation may be realized by other methods.

When the degree of damage per generated power is maximized near the rated wind speed as shown in FIG. However, a reduction in generated power due to a decrease in rotational speed increases the inflow angle to the blades, which may lead to an increase in the degree of damage.

Therefore, the pitch angle of the blades is controlled to the feather side (the side that reduces the angle of attack of the blades) to a greater extent than usual in order to maintain the upper limit of the rotation speed while lowering the generator torque. and reduce the angle of attack of the blade.

However, depending on the degree of damage to be monitored, it may not depend on the angle of attack of the blade, so the retraction operation may be performed by reducing the number of revolutions compared to normal while maintaining the torque. Here, the control amount during normal operation means that the power curve described in the catalog of the wind turbine generator 1 is realized when the ideal wind assumed in the design conditions or the like flows in without performing the degenerate operation. In many cases, it is the control amount that maximizes the amount of power generation.

In order to reduce the torque while keeping the rotation speed at the upper limit near the rated wind speed, it is necessary to modify the method of determining the control amount of the pitch angle. Around the rated wind speed, the pitch angle control amount is determined based on the rotational speed and torque. During degeneracy operation, by changing the gain of the pitch angle control amount based on the torque to the value determined in the second embodiment, control that maximizes the power generation amount during degeneracy operation is realized.

For example, as shown in equation (1), the pitch angle control amount (positive on the feather side) Δθ is obtained by subtracting the rated torque (torque at the rated output) Qrated, which is the target torque value, from the current torque Q. Consider the case where it is determined by multiplying the difference by a proportional gain k (>0).
[Number 1]
Δθ=k(Q-Qrated) (1)
In equation (1), when the torque is smaller than the rated torque, Δθ becomes negative and the pitch angle is controlled to the fine side (to increase the angle of attack of the blade). Therefore, during degenerate operation, this proportional gain is made smaller than that during normal operation, thereby suppressing the control of directing the pitch angle to the fine side.

FIG. 9 is a diagram for explaining a degeneracy operation method by increasing the pitch angle feather control amount, and shows the relationship between the generated power and the pitch angle control amount with respect to the average wind speed. The relationship between the generated power and the pitch angle control amount is indicated by a solid line, and this should be indicated by a dotted line during degenerate operation. As a result, as shown in FIG. 9, the pitch angle can be controlled to the feather side compared to the normal time, and the degeneracy operation with reduced torque is realized while maintaining the rotational speed at the upper limit value. Further, by decreasing the proportional gain as the degree of damage needs to be reduced more greatly, it becomes possible to adjust the strength of the degenerate operation as shown in FIG. Although a simple proportional control has been described here as an example, other control methods may be used as long as the strength of degenerate operation can be adjusted using a gain or the like.

In addition to the degeneracy operation method described above, the following method may be used when degeneracy operation is required in an arbitrary wind speed range. In this degenerate operation method, by changing the upper limit value of the torque based on the wind speed in the wind speed measurement unit 31, an increase in the rotation speed or the feather control amount is encouraged.

A first method of performing degenerate operation in an arbitrary wind speed range will be described with reference to FIG. 10 . FIG. 10 is a diagram for explaining a degeneracy operation method using a stepped power curve based on wind speed. Similar to FIG. 9, it shows the relationship between the generated power and the pitch angle control amount with respect to the average wind speed. For example, as shown in FIG. 10, consider reducing the generated power stepwise in a partial region above the rated wind speed to perform degenerate operation. Rated torque is normally used as the torque upper limit at rated output. In this degenerate operation, when the wind speed measured by the wind speed measurement unit 31 is the wind speed for the degenerate operation, the torque upper limit value is reduced from the rated torque according to the wind speed. The wind speed used to determine the upper torque limit value may be an instantaneous value or a statistical value such as an average wind speed for 10 minutes. When the torque upper limit value is reduced in this way, the rotation speed of the rotor increases. Realized.

A second method of performing degenerate operation in an arbitrary wind speed range will be described with reference to FIG. 11 . FIG. 11 is a diagram for explaining a degeneracy operation method using a concave power curve based on wind speed. Similar to FIGS. 9 and 10, it shows the relationship between the generated power and the pitch angle control amount with respect to the average wind speed. In FIG. 10, the generated power is changed stepwise, but the torque upper limit value is changed continuously according to the wind speed, and degenerate operation is performed so as to form a smooth concave power curve as shown in FIG. good too.

FIG. 12 is a diagram for explaining the difference between the degeneracy operation based on the degree of damage per generated power and the conventional degeneracy operation. 12 shows the relationship between the generated power and the pitch angle control amount with respect to the average wind speed, as in FIGS. 9, 10 and 11. In FIG. While the dotted line represents the conventional degenerate operation in which the rated output is uniformly reduced. Further, in the case of the method of the present invention in which the degeneracy operation is performed near the cutout wind speed, the power curve has a shape as shown by the one-dot chain line in FIG. In this degeneracy operation method, unlike the conventional degeneracy operation (dotted line) in which the rated output is uniformly reduced, the wind speed range in which degeneracy operation is performed in accordance with the methods of Embodiments 1 and 2 is limited based on the degree of damage per generated power. By doing so, it is possible to localize the drop in the power curve and maximize the amount of power generated during degenerate operation.

Although the upper limit of the torque is changed according to the wind speed here, the degenerate operation may be performed with the upper limit of the rotational speed changed according to the wind speed.

FIG. 13 is a diagram for explaining a degenerate operation method by increasing the rotation speed of the generator. This figure shows the relationship between the generated power and the rotation speed with respect to the average wind speed. When this degenerate operation is performed in a low wind speed range below the rated rotation speed, the wind speed range in which the degenerate operation is performed increases the rotation speed compared to normal operation, as shown in FIG. 13 . Also in this case, since the angle of inflow to the blade is reduced by increasing the rotation speed, retraction operation is realized by reducing the angle of attack of the blade. Here, by changing the upper limit of the torque, the torque is reduced more than the normal time, but depending on the operating state, the lower limit of the torque may be changed to reduce the torque.

Furthermore, when the degree of damage per generated power is maximized near the cut-in wind speed, in addition to the above method, the cut-in wind speed may be increased more than normal to perform degenerate operation.

By using the degeneracy operation method described above, according to the third embodiment, degeneracy operation that maximizes the amount of power generated during the degeneracy operation can be performed.

It is desirable that the power curve should be as follows. Regarding the power curve, the wind speed that changes to any one of a ramp shape, a concave shape, and a step shape is in the vicinity of the rated wind speed, and preferably within 4 m/s before and after the rated wind speed. Also, when the power curve changes to ramp, concave, or stepped near the rated wind speed, it is desirable that the rotation speed does not change from normal and the torque is lower than normal. Also, when the power curve changes to any of a ramp shape, a concave shape, and a step shape near the rated wind speed, it is desirable that the torque does not change from the normal time and the rotation speed is lower than the normal time.

In the fourth embodiment, a degeneracy operation method will be described in which the degree of fatigue damage in the degeneracy operation of the embodiments 1-3 is replaced with, for example, the wear and deterioration of the parts constituting the wind turbine generator. Parts to be monitored for degenerate operation include, but are not limited to, bearings, gears, actuators, brake pads, lubricating oil, grease, electrical equipment, and the like.

The configuration of the control device 12 and the controlled object 30 of the wind turbine generator 1 in the fourth embodiment when the degeneration operation is performed using wear and deterioration of parts may be the same as in FIGS. 3 and 6, and FIG. 6 is used here. to explain. However, the processing in the control amount measuring unit 41, the load measuring unit 32, the damage degree calculating unit 33, and the damage degree database DB1a may differ from those in the first and second embodiments.

The control amount measuring unit 41 in the fourth embodiment not only measures the rotor rotation speed, the generator rotation speed, the pitch angle, the yaw error, the generator output, etc. as the control amount or control target value in the controlled object 30, but also It also measures power consumption, oil pressure, etc. in various control mechanisms that are monitored.

In the load measuring unit 32, the strain sensor 24, an acceleration sensor, a pressure sensor, a microphone, a camera, a current/voltage sensor, a temperature sensor, a chromaticity sensor, a viscosity sensor, a particle sensor, an oil leak sensor, and other sensors suitable for the monitoring target , to measure the load, damage, wear and deterioration of the monitored object. Sensors other than those listed here may be used as they relate to the load, damage, wear and deterioration being monitored.

The damage degree calculator 33 quantifies the degree of damage, wear, and deterioration in a predetermined time from the monitored sensor data. For example, a power spectrum can be acquired from a bearing or gear accelerometer to calculate the amount of change in power at the monitored frequency, or a particle sensor can be used to calculate the amount of turbidity in lubricating oil. . Moreover, a plurality of sensor data may be integrated, the degree of abnormality of the monitored object may be calculated by machine learning, etc., and the amount of change in the degree of abnormality may be calculated. In addition, a cumulative value of damage, wear, and deterioration to be monitored is calculated by accumulating degrees of damage, wear, and deterioration over a predetermined period of time. When the degree of damage, wear, and deterioration at the time of measurement represents a cumulative value, such as the power spectrum, lubricating oil turbidity, and degree of anomaly described above, instead of accumulating the amount of change, it is calculated from the latest measured value. The degree of damage, wear and deterioration may be used.

The damage degree database DB1a stores the relationship between the average wind speed for a predetermined time period, the average value or target value of various control variables, and the amount of change in the degree of damage, wear, and deterioration.

Control variables include, for example, rotor rotation speed, generator rotation speed, torque, pitch angle, yaw error, generator output, power consumption in various control mechanisms, and oil pressure. At the time of saving, all the data at each predetermined time may be saved as they are, or the average amount of change with respect to the average wind speed and various control variables may be saved as statistical values.

The control amount calculation unit 37a calculates the control amount of the controlled object 30 and the wind speed range in which the control is changed by replacing the degree of damage with the degree of wear or deterioration in the same manner as in the embodiment 1-3.

By using the degeneracy operation method described above, according to the fourth embodiment, it is possible to perform degeneracy operation that maximizes the amount of power generated during degeneracy operation for various parts by using the degree of wear and deterioration other than the degree of damage. becomes.

1: Wind turbine generator 2: Blades 3: Hub 4: Nacelle 5: Tower 6: Main shaft 7: Gearbox 8: Generator 9: Main frame 10: Rotor 11: Power converter 12: Control device 21: Pitch angle control Mechanism 22: Yaw control mechanism 23: Anemometer 24: Strain sensor 30: Control object 31: Wind speed measurement unit 32: Load measurement unit 33: Damage degree calculation unit DB1, DB1a: Damage degree database DB2, DB2a: Power curve database DB3: Operation plan database 37, 37a: control amount calculation unit 41: control amount measurement unit 42: wind condition prediction unit

Claims (18)

A wind power generator having at least a rotor, a nacelle, and a tower that supports the nacelle, and performing degeneration operation by a control device,
The control device includes a damage degree database that defines the relationship between the degree of damage to parts per unit time and wind speed, a power curve database that defines the relationship between output and wind speed, and calculation from the degree of damage and the power curve. Equipped with a control amount calculation unit that calculates the degree of damage per generated power against the wind speed and calculates the control amount for degenerate operation,
The wind turbine generator , wherein the control device performs the degeneracy operation when the degree of damage per generated power for the obtained wind speed exceeds a specified value. The wind turbine generator according to claim 1 ,
The wind turbine generator, wherein the control amount calculation unit controls any one of the rotation speed, torque, blade pitch angle, and yaw angle of the wind turbine generator according to the control amount of the degeneracy operation. The wind turbine generator according to claim 1 ,
The wind turbine generator, wherein the power curve is locally reduced compared to a normal time when the degeneracy operation is not performed due to the calculation of the control amount by the control amount calculation unit. The wind turbine generator according to claim 1 ,
A wind power generator comprising a plurality of power curves corresponding to at least one of a wind speed range in which the power curve locally decreases or a change in intensity of degeneracy operation. The wind turbine generator according to claim 1 ,
The wind turbine generator according to claim 1, wherein the power curve changes to any one of a ramp shape, a recessed shape, and a stepped shape with respect to a normal time when the degeneracy operation is not performed according to the calculation of the control amount by the control amount calculation unit. The wind turbine generator according to claim 5,
The wind turbine generator, wherein the power curve changes to any one of a ramp shape, a concave shape, and a step shape at a wind speed near a rated wind speed. The wind turbine generator according to claim 5 ,
The wind turbine generator, wherein the power curve changes in any one of a ramp shape, a concave shape, and a step shape within 4 m/s before and after a rated wind speed. The wind turbine generator according to claim 5 ,
A wind power generator characterized in that when the power curve changes to one of a ramp shape, a concave shape, and a step shape near the rated wind speed, the rotation speed does not change from normal and the torque is lower than normal. Device. The wind turbine generator according to claim 5 ,
A wind power generator characterized in that, when the power curve changes to one of a ramp shape, a concave shape, and a step shape near the rated wind speed, the torque does not change from the normal time, and the rotation speed is lower than the normal time. Device. The wind turbine generator according to claim 1 ,
The wind turbine generator, wherein the control amount calculation unit calculates the control amount so as to smooth the maximum value of the degree of damage per generated power with respect to the wind speed . The wind turbine generator according to claim 1 ,
The wind power generator according to claim 1, wherein the database of the degree of damage stores the relationship between the degree of damage to parts per unit time, the wind speed, and the amount of control when the control is changed. The wind turbine generator according to claim 1 ,
The control amount calculation unit calculates the wind speed range in which the control amount or control is changed by the damage degree obtained by the inner product of the wind speed frequency distribution based on the wind condition prediction and the damage degree distribution at the time of control change, and the cumulative damage degree up to now. A wind power generator characterized in that the estimated cumulative damage degree obtained by the sum is determined so as to match the allowable value of the operation plan. The wind turbine generator according to claim 1 ,
The wind turbine generator, wherein the database of the degree of damage measures the data during operation and sequentially updates the relationship between the degree of damage per unit time of the component, the wind speed, and the control amount when the control is changed. The wind turbine generator according to claim 1,
The wind turbine generator, wherein the degree of damage is a degree of fatigue damage, a power spectrum of vibration, and turbidity. The wind turbine generator according to claim 1,
When the degree of damage or deterioration per generated power with respect to the wind speed is maximized near the rated wind speed of the wind power generator, the control device sets the feather operation amount of the blade pitch angle to be lower than normal when the retraction operation is not performed. , a wind power generator characterized by increasing A wind turbine generator according to claim 15,
The wind turbine generator, wherein the control device starts the feathering operation of the blade pitch angle at a wind speed lower than normal. A wind turbine generator according to claim 15,
The wind turbine generator, wherein the control device increases the feather operation amount of the blade pitch angle within 4 m/s before and after the rated wind speed. A wind power generation method for performing degeneration operation using a computer for a wind turbine generator having at least a rotor, a nacelle, and a tower for supporting the nacelle,
Equipped with a damage database that defines the relationship between the degree of damage to parts per unit time and wind speed, and a power curve database that defines the relationship between output and wind speed,
The degree of damage per generated power with respect to the wind speed calculated from the degree of damage and the power curve is calculated, and the control amount for the degeneracy operation is calculated. A wind power generation method characterized by carrying out.

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