CN114251236B

CN114251236B - Fault early warning method and fault early warning device for variable pitch drive

Info

Publication number: CN114251236B
Application number: CN202011010739.2A
Authority: CN
Inventors: 马磊; 王大为; 卢勇
Original assignee: Jinfeng Technology Co ltd
Current assignee: Jinfeng Technology Co ltd
Priority date: 2020-09-23
Filing date: 2020-09-23
Publication date: 2024-04-12
Anticipated expiration: 2040-09-23
Also published as: CN114251236A

Abstract

A fault early warning method and a fault early warning device for a variable pitch drive are disclosed. The fault early warning method comprises the following steps: calculating a theoretical variable pitch voltage of the variable pitch motor based on the operation data of the variable pitch motor; acquiring actual variable pitch voltage of a variable pitch motor; and determining whether the pitch drive will fail based on the theoretical pitch voltage and the actual pitch voltage.

Description

Fault early warning method and fault early warning device for variable pitch drive

Technical Field

The present disclosure relates generally to the field of wind power generation technology, and more particularly, to a fault early warning method and a fault early warning device for a pitch drive of a pitch system of a wind turbine generator set.

Background

With the gradual expansion of the scale of the wind generating set and the gradual perfection of the safety protection of the wind generating set, the running power generation performance of the wind generating set, namely the power generation capacity and the availability of the wind generating set, is more and more emphasized. On the other hand, the safety of the wind generating set is strictly ensured while the power generation benefit is pursued.

In a wind power generator set, one of the main functions of the pitch system is to act as a pneumatic brake system for the set. The electric pitch system ensures the safe and stable operation of the wind generating set through multiple detection and control means and multiple redundancy designs. Any failure-induced shutdown will feathered the blades to a 90 degree position. Therefore, the pitch system plays a critical role in the stability and safety of the unit, and particularly as an aerodynamic brake, the pitch system is required to have high reliability and safety.

However, during operation of the wind turbine, the pitch drive, the pitch motor, or the backup power source of the pitch system may fail, which may result in the blades of the wind turbine failing to retract to a safe position (e.g., pitch angle 88 degrees). If the blades of the wind generating set cannot be retracted to the safe position, the rotating speed of the wind generating set cannot be reduced under the action of wind force, and overspeed and even galloping of the wind generating set are caused. Especially, as the number of fans is continuously increased, batch faults especially relate to faults of unit safety, and are directly related to development and fate of wind power enterprises, so that more and more importance is placed on research and application such as card oar detection, large-component reliability detection, grid-connected safety detection and the like.

When the clamping paddle working condition is detected, the fault of the variable paddle driver is found to be the most of the clamping paddle. By performing linear regression calculation on the total duty ratio of the two faults of the "pitch drive OK signal loss fault" and the "blade position deviation large fault", the linear correlation coefficient is found to be r= 0.98295, so that the linear correlation coefficient of the two faults is very high (when |r|=1, the two variables are completely linear correlation), that is, the correlation of the fault co-factor is very high. After the variable pitch drive fails, the variable pitch motor cannot be driven to run any more, so that the blades cannot be retracted, and the safety of the wind generating set is seriously affected.

In fact, in wind power enterprises, the operation of the wind generating set is critical, and the fault of the wind generating set has a great influence on the whole system. However, as the causes of the faults of the pitch drive are various (generally, tens or even tens), even the results of superposition of various factors are possible, if only the influence of external factors such as temperature, wind intensity, capacitance voltage, load and the like is analyzed, on one hand, the feature extraction is difficult, and on the other hand, the fault of the pitch drive with different fault codes is difficult to adapt to.

At present, for the fault of the pitch drive, a common method is to switch to the power grid voltage to directly supply power to the pitch motor after the fault of the pitch drive, however, the method has a certain limitation.

Firstly, because the power grid is alternating current, the method is only applicable to alternating current motors and is not applicable to direct current motors; the volume of the alternating current motor is much larger than that of the direct current motor, and the advantages of the direct current motor are more and more obvious along with the continuous increase of the capacity of the unit, and more applications are obtained.

Secondly, because the power supply line of the power grid needs to be controlled and switched by the contactor during operation, the failure of the contactor can cause the feathering shutdown of the wind generating set due to false triggering of the fault.

Thirdly, under the working condition, the shutdown feathering is powered off to stop the motor, and as the capacity of the unit increases, the motor suddenly stops to cause larger vibration of the unit.

Disclosure of Invention

The embodiment of the disclosure provides a fault early warning method and a fault early warning device for a variable pitch drive, which can take errors in advance by early warning the fault of the variable pitch drive and prevent blades from clamping paddles.

In one general aspect, there is provided a fault warning method of a pitch drive, the fault warning method comprising: calculating a theoretical variable pitch voltage of the variable pitch motor based on the operation data of the variable pitch motor; acquiring actual variable pitch voltage of a variable pitch motor; and determining whether the pitch drive will fail based on the theoretical pitch voltage and the actual pitch voltage.

Optionally, the operation data comprises an actual pitch speed of the pitch motor and/or an operation frequency of the pitch motor.

Optionally, the step of calculating a theoretical pitch voltage of the pitch motor comprises: and calculating the product of the actual pitch speed of the pitch motor and the running frequency of the pitch motor as the theoretical pitch voltage of the pitch motor.

Optionally, the step of calculating a theoretical pitch voltage of the pitch motor comprises: and obtaining a theoretical variable pitch voltage corresponding to the actual variable pitch speed according to the actual variable pitch speed of the variable pitch motor and a linear relation obtained by fitting the historical variable pitch voltage and the historical variable pitch speed of the variable pitch motor.

Optionally, the step of determining whether the pitch drive will fail based on the theoretical pitch voltage and the actual pitch voltage comprises: based on the magnitude relation of the theoretical pitch voltage and the actual pitch voltage and the magnitude relation of the actual pitch speed of the pitch motor and the given pitch speed, it is determined whether the pitch drive will fail.

Optionally, the step of determining whether the pitch drive will fail comprises: determining whether the actual pitch voltage is greater than N times of the theoretical pitch voltage for a threshold time, wherein N is a real number greater than 1; when the actual pitch voltage is greater than N times of the theoretical pitch voltage for a threshold time, determining whether the actual pitch speed of the pitch motor reaches a given pitch speed; if the actual pitch speed reaches the given pitch speed, it is determined that the pitch drive will fail.

Optionally, the step of determining whether the pitch drive will fail based on the theoretical pitch voltage and the actual pitch voltage comprises: based on the magnitude relation of the theoretical pitch voltage and the actual pitch voltage, it is determined whether the pitch drive will fail.

Optionally, the step of determining whether the pitch drive will fail comprises: determining whether the actual pitch voltage is greater than N times of the theoretical pitch voltage for a threshold time, wherein N is a real number greater than 1; when the actual pitch voltage is greater than N times the theoretical pitch voltage for a threshold time, it is determined that the pitch drive will fail.

Optionally, the fault early warning method further includes: before calculating a theoretical pitch voltage of the pitch motor, it is determined whether the magnetic flux of the pitch motor is saturated based on the pitch motor magnetic flux information contained in the output information of the pitch drive, and it is determined that the pitch drive will fail in response to the magnetic flux of the pitch motor being saturated.

Optionally, the fault early warning method further includes: before calculating a theoretical pitch voltage of the pitch motor, a torque boost amount of the pitch drive is obtained, and in response to the torque boost amount of the pitch drive exceeding a preset threshold, it is determined that the pitch drive will fail.

In another general aspect, there is provided a fault handling method of a pitch drive, the fault handling method comprising: adjusting the output of the pitch drive in response to determining that the pitch drive will fail by the failure warning method as described above; and after a predetermined time, controlling the output of the pitch drive to resume normal.

Optionally, the fault handling method further includes: in response to determining that the pitch drive will fail by the failure early warning method as described above, determining whether a risk is avoidable; in response to determining that the risk evacuable, the step of adjusting the output of the pitch drive is performed.

Optionally, the step of determining whether the risk is avoidable comprises: detecting the rotating speed of the wind generating set and the wind speed of the position of the wind generating set; determining whether the detected rotational speed is less than a threshold rotational speed, and determining whether the detected wind speed is less than a threshold wind speed; in response to determining that the detected rotational speed is less than the threshold rotational speed and the detected wind speed is less than the threshold wind speed, determining that the risk may be circumvented.

Optionally, the fault handling method further includes: controlling the yaw preset angle of the wind driven generator in response to determining that the pitch drive will fail by the failure early warning method as described above; detecting whether the rotating speed of the wind generating set is reduced; in response to detecting a decrease in rotational speed of the wind park, the step of adjusting the output of the pitch drive is performed.

Optionally, adjusting the output of the pitch drive: including suspending the output of the pitch drive.

Optionally, adjusting the output of the pitch drive comprises: the output of the pitch drive is adjusted by reducing the given pitch speed provided to the pitch drive.

Optionally, the fault handling method further includes: determining, during the predetermined time, whether the angles of the individual blades are consistent in response to adjusting the output of the pitch drive; and controlling the shutdown of the wind generating set in response to determining that the angles of the blades are inconsistent.

Optionally, the step of determining whether the angles of the respective blades are consistent during the predetermined time includes: setting the angle of a first blade at the moment when the determined pitch drive will fail as a reference angle value, wherein the first blade is a blade corresponding to the determined pitch drive which will fail; taking the sum of the reference angle value and the additional angle value as an angle upper limit value, and taking the difference between the reference angle value and the additional angle value as an angle lower limit value; monitoring during the predetermined time whether the angle of the other blade exceeds an angle threshold range defined by an angle upper limit value and an angle lower limit value; in response to monitoring that the angle of any of the blades exceeds the angle threshold range, an angular inconsistency of each blade is determined.

In another general aspect, there is provided a fault warning device of a pitch drive, the fault warning device comprising: a voltage calculation unit configured to calculate a theoretical pitch voltage of the pitch motor based on operation data of the pitch motor; a voltage acquisition unit configured to acquire an actual pitch voltage of the pitch motor; and a fault early warning unit configured to determine whether the pitch drive will fail based on the theoretical pitch voltage and the actual pitch voltage.

In another general aspect, there is provided a fault handling apparatus of a pitch drive, the fault handling apparatus comprising: an output adjustment unit configured to adjust an output of the pitch drive in response to the failure warning device determining that the pitch drive will fail as described above; and an output restoration unit configured to control the output of the pitch drive to be restored to normal after a predetermined time.

In another general aspect, there is provided a computer readable storage medium storing a computer program, characterized in that the computer program, when executed by a processor, implements a failure warning method of a pitch drive as described above or a failure handling method of a pitch drive as described above.

In another general aspect, there is provided a controller of a wind power generation set, the controller comprising: a processor; and a memory storing a computer program which, when executed by the processor, implements the failure warning method of the pitch drive as described above or the failure processing method of the pitch drive as described above.

According to the fault early-warning method and the fault early-warning device of the pitch drive, starting from the working principle of the pitch drive (namely, the voltage compensation/torque compensation), the fault early-warning can be performed on the pitch drive 25-30 seconds in advance. During this time, there is enough time to complete the anti-seize operation and control.

On the other hand, according to the fault processing method and the fault processing device for the pitch drive of the embodiment of the disclosure, since the operation of restarting the pitch drive in the power failure is not needed and the time for adjusting the output of the pitch drive can be set, the safety influence on the wind generating set is small, and the problem of brake band-type brake abrasion caused by restarting the pitch drive in the power failure is avoided. On the other hand, by performing yaw of the side wind after determining that the pitch drive will fail, such that the wind force received by the blades of the wind turbine generator is reduced, the rotational speed is reduced, and then performing operation control such as adjusting the output of the determined pitch drive that will fail and then restoring the normal output thereof, the safety of the wind turbine generator can be further protected. In addition, by judging whether the angles of the blades are consistent, the load increase of the wind generating set caused by inconsistent angles of the three blades after the triggering failure of the pitch drive is reduced. Further, by adjusting the output of the pitch drive by reducing the given pitch speed provided to the pitch drive, rather than suspending the output of the pitch drive, delays caused by powering down the pitch drive, or suspending the operation of the pitch drive, may be reduced.

Additional aspects and/or advantages of the present general inventive concept will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the general inventive concept.

Drawings

The foregoing and other objects and features of embodiments of the present disclosure will become more apparent from the following description taken in conjunction with the accompanying drawings in which the embodiments are shown, in which:

FIG. 1 is a diagram illustrating an example of a pitch system of a wind turbine according to an embodiment of the present disclosure;

FIG. 2 is a diagram illustrating an example of field operational data of a pitch motor;

FIG. 3 is a flow chart illustrating a fault warning method of a pitch drive according to an embodiment of the present disclosure;

FIG. 4 is a flowchart illustrating an example of a fault warning method of a pitch drive according to an embodiment of the present disclosure;

FIG. 5 is a flowchart illustrating another example of a fault warning method of a pitch drive according to an embodiment of the present disclosure;

FIG. 6 is a flow chart illustrating a fault handling method of a pitch drive according to an embodiment of the present disclosure;

FIG. 7 is a flowchart illustrating an example of a fault handling method of a pitch drive according to an embodiment of the present disclosure;

FIG. 8 is a flowchart illustrating another example of a fault handling method of a pitch drive according to an embodiment of the present disclosure;

FIG. 9 is a block diagram illustrating a fault warning apparatus of a pitch drive according to an embodiment of the present disclosure;

FIG. 10 is a block diagram illustrating a fault handling apparatus of a pitch drive according to an embodiment of the present disclosure;

FIG. 11 is a block diagram illustrating a controller of a wind turbine according to an embodiment of the present disclosure.

Detailed Description

The following detailed description is provided to assist the reader in obtaining a thorough understanding of the methods, apparatus, and/or systems described herein. However, various changes, modifications, and equivalents of the methods, apparatuses, and/or systems described herein will be apparent after an understanding of the disclosure of the present application. For example, the order of operations described herein is merely an example and is not limited to those set forth herein, but may be altered as will be apparent after an understanding of the disclosure of the present application, except for operations that must occur in a particular order. Furthermore, descriptions of features known in the art may be omitted for clarity and conciseness.

The features described herein may be embodied in different forms and should not be construed as limited to the examples described herein. Rather, the examples described herein have been provided to illustrate only some of the many possible ways to implement the methods, devices, and/or systems described herein, which will be apparent after an understanding of the present disclosure.

As used herein, the term "and/or" includes any one of the listed items associated as well as any combination of any two or more.

Although terms such as "first," "second," and "third" may be used herein to describe various elements, components, regions, layers or sections, these elements, components, regions, layers or sections should not be limited by these terms. Rather, these terms are only used to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, a first member, first component, first region, first layer, or first portion referred to in the examples described herein may also be referred to as a second member, second component, second region, second layer, or second portion without departing from the teachings of the examples.

In the description, when an element (such as a layer, region or substrate) is referred to as being "on" another element, "connected to" or "coupled to" the other element, it can be directly "on" the other element, be directly "connected to" or be "coupled to" the other element, or one or more other elements intervening elements may be present. In contrast, when an element is referred to as being "directly on" or "directly connected to" or "directly coupled to" another element, there may be no other element intervening elements present.

The terminology used herein is for the purpose of describing various examples only and is not intended to be limiting of the disclosure. Singular forms also are intended to include plural forms unless the context clearly indicates otherwise. The terms "comprises," "comprising," and "having" specify the presence of stated features, amounts, operations, components, elements, and/or combinations thereof, but do not preclude the presence or addition of one or more other features, amounts, operations, components, elements, and/or combinations thereof.

Unless defined otherwise, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs after understanding this disclosure. Unless explicitly so defined herein, terms (such as those defined in a general dictionary) should be construed to have meanings consistent with their meanings in the context of the relevant art and the present disclosure, and should not be interpreted idealized or overly formal.

In addition, in the description of the examples, when it is considered that detailed descriptions of well-known related structures or functions will cause a ambiguous explanation of the present disclosure, such detailed descriptions will be omitted.

The fault early warning system (FPS) uses the original operation data in the storage system or equipment, and converts the original operation data into a dynamic equipment online model under the support of a similar theory through multiple regression, principal component analysis and other technologies in the data mining technology. And comparing the real-time predicted value generated by the calculation of the dynamic equipment model with the measured value of the equipment measuring point, and issuing early-stage fault state early warning of the equipment according to the comparison result. Based on the reasons, the disclosure designs a fault early warning method of the variable pitch drive, which is used for early warning of the fault of the variable pitch drive.

Fig. 1 is a diagram illustrating an example of a pitch system of a wind turbine according to an embodiment of the present disclosure.

Referring to fig. 1, the pitch system may include a pitch motor 101, a supercapacitor 102, a controller 103, a pitch drive 104, an enable switch (limit switch) 105, a brake relay 106, and an encoder 107.

When pitch drive 104 is operating normally, enable switch (limit switch) 105 is in a closed state and pitch drive 104 is powered. After the controller 103 receives the pitch speed indication of the main controller of the wind generating set, or when the controller 103 detects that the pitch system is out of order and feathering is performed autonomously, the controller 103 sends a speed command and an enable signal to the pitch drive 104. After receiving the speed command and the enable signal, the pitch drive 104 controls the brake relay 106 to open the brake, and provides output voltage through power output to drive the pitch motor 101 to rotate, so as to realize the pitch function.

Encoder 107 may encode the amount of change in pitch angle of the blades of the wind park and provide its value to pitch drive 104 and/or controller 103. Pitch drive 104 and/or controller 103 may calculate the rotational speed of pitch motor 101 based on the read encoder values. Pitch drive 104 compares the calculated rotational speed to the value of the speed command sent by controller 103 to pitch drive 104. If the calculated rotational speed is less than the speed commanded value, pitch drive 104 may increase the voltage of the power output to increase the rotational speed of pitch motor 101. If the calculated rotational speed is greater than the speed command value, pitch drive 104 decreases the power output voltage to reduce the rotational speed of pitch motor 101. In this way, the rotational speed of the pitch motor 101 may eventually be brought to a value corresponding to a given speed command.

Pitch controller 103 may control the overall operation of the pitch system and may communicate with the main control of the wind turbine, receive control commands sent by the main controller and/or send status information of the pitch system to the main controller. The pitch controller 103 may perform a fault early warning method and a fault handling method of a pitch drive according to an embodiment of the present disclosure, which will be described later.

The working principle of the pitch drive (also called frequency converter) is: in order to keep the magnetic flux of the pitch motor unchanged, the frequency conversion is performed and the voltage transformation is also needed. The condition that the frequency converter keeps the magnetic flux unchanged is:

wherein f _x The running frequency of the variable pitch motor is Hz; e (E) _x Is operated at a frequency f _x When the motor stator is used, the unit of self-induced electromotive force of one-phase winding is V.

However, for reasons such as operation efficiency of the pitch motor, only the following can be achieved in practice:

wherein U is _x Is operated at a frequency f _x And when the variable pitch drive outputs output voltage to the variable pitch motor, the unit is V. In other words, U _x /f _x Equation (2) is satisfied, and equation (1) is not truly satisfied. The reason for this can be as shown in equation (3).

T _m ＝K _m Φ ₁ i ₂ cosφ ₂ (3)

Wherein T is _m Is the electromagnetic torque, K, of the variable pitch motor _m Is the torque coefficient of the variable pitch motor, phi ₁ Is the magnetic flux of each pole of the variable-pitch motor, cos phi ₁ Is the power factor, i of the rotor side of the variable pitch motor ₂ Is the output current of the variable pitch motor.

In equation (3), i ₂ The rated current of the pitch motor is not allowed to be exceeded. The amount of load carrying capacity of the pitch motor is then mainly dependent on the flux of the pitch motor. U in circuit of stator winding of asynchronous motor _x And E is _x The difference between these is mainly the voltage drop of the stator winding resistance, as shown in equation (4).

U _x ＝-E _X +I ₁ r (4)

I ₁ Is the phase current of the stator; r is the resistance of the stator one-phase winding. Therefore, the magnitude of the magnetic flux changes from equation (4) to equation (5).

Wherein K phi is the magnetic flux coefficient of the pitch motor.

As can be seen from equation (5), since both back emf and voltage are frequency dependent, and the resistance drop Δu=i ₁ r is not frequency dependent, so when the pitch motor is at frequency f _x In operation, the magnitude of the magnetic fluxAnd the following factors.

First, the output voltage of the pitch drive (power supply voltage of the pitch motor), U _x The larger the magnetic flux, the larger. Second, the motor is lightly loaded. The heavier the load, the greater the current and the magnetic flux will decrease. The ratio of the voltage drop in the supply voltage. Because the output voltage of the pitch drive will then drop as the operating frequency drops, but the resistance drop will be constant if the load torque is constant, the proportion of the resistance drop in the supply voltage will increase, which will also result in a decrease in magnetic flux.

Therefore, when an abnormality occurs in the operation state of the pitch motor or the pitch drive, the load increases, and the magnetic flux decreases. If it is desired that the pitch drive is operated with a rated magnetic flux, the output voltage of the pitch drive is only increased. This method of increasing the flux by appropriately compensating the voltage, thereby enhancing the load carrying capacity of the pitch motor at low frequencies is called voltage compensation, also called torque compensation. When the operating frequency is different, the amount of voltage compensation is also different.

The present disclosure utilizes such features when the pitch drive is operating to monitor and analyze the operational data of the pitch system on-line, thereby pre-warning the pitch drive of failure before the pitch drive triggers the failure.

Fig. 2 is a diagram showing an example of field operation data of a pitch motor. Curve 201 indicates the normal shaft pitch motor voltage, curve 202 indicates the abnormal shaft pitch motor voltage, and curve 203 indicates the abnormal shaft driver ok signal condition. Here, the shaft may correspond to a blade. Alternatively, three blades each correspond to a shaft, each shaft having a pitch controller, a pitch drive, and a pitch motor. However, the present disclosure is not limited thereto.

Referring to fig. 2, the pitch motor voltage of the abnormal shaft is obviously increased around-23 s, and the ok signal of the driver is a normal heartbeat signal (the period is 100 ms); whereas at time 0s the driver ok signal becomes a failed signal (period about 500ms, interval greater than 2 s). Therefore, through analysis of the operation mechanism of the pitch drive, the voltage of the pitch motor output by the pitch drive can be monitored in the operation process of the pitch drive, so that the fault of the pitch drive is early warned.

Fig. 3 is a flowchart illustrating a fault warning method of a pitch drive according to an embodiment of the present disclosure.

According to embodiments of the present disclosure, the fault warning method may operate in each pitch control. However, the disclosure is not limited thereto, and the fault warning method may also be run in a main controller or in other controllers of the wind power plant. Alternatively, the fault warning method may also be run in a controller of the wind farm or any other controller capable of communicating with the wind park.

Referring to fig. 3, in step S301, a theoretical pitch voltage of the pitch motor is calculated based on operation data of the pitch motor. Here, the operation data of the pitch motor may include an actual pitch speed of the pitch motor and/or an operation frequency of the pitch motor. The actual pitch speed and/or operating frequency of the pitch motor may be determined by an encoder value provided by an encoder in the pitch system. However, the present disclosure is not limited thereto, and the actual pitch speed and/or operating frequency of the pitch motor may be determined by any method.

Specifically, in step S301, the product of the actual pitch speed of the pitch motor and the operating frequency of the pitch motor may be calculated as the theoretical pitch voltage of the pitch motor. That is, u=v×f, where U represents the theoretical pitch voltage of the pitch motor, v represents the actual pitch speed of the pitch motor, and f represents the operating frequency of the pitch motor.

Alternatively, in step S301, the theoretical pitch voltage corresponding to the actual pitch speed may be obtained according to the actual pitch speed of the pitch motor and the linear relationship obtained by fitting the historical theoretical pitch voltage of the pitch motor and the historical pitch speed. For example, a curve fitting may be performed on a historical theoretical pitch voltage and a historical pitch speed of the pitch motor by an experimental method, so as to obtain a linear relationship between the historical theoretical pitch voltage and the historical pitch speed as shown in an equation u=a+b×x, where U represents the historical theoretical pitch voltage of the pitch motor, X represents the historical pitch speed of the pitch motor, and a and B are a first coefficient and a second coefficient obtained by curve fitting respectively. Then, the theoretical pitch voltage U corresponding to the actual pitch speed can be calculated by substituting the actual pitch speed as X into the above equation.

In step S302, an actual pitch voltage of the pitch motor may be obtained. Here, the voltage of the pitch motor may be detected by a voltage sensor provided on the pitch motor, or the voltage of the pitch motor may be detected by a voltage sensor provided on the pitch drive. However, the present disclosure is not limited thereto, and the voltage of the pitch motor may be detected in various ways. Alternatively, step S302 may be performed before step S301.

In step S303, it may be determined whether the pitch drive will fail based on the theoretical pitch voltage and the actual pitch voltage.

Specifically, in the case of calculating the theoretical pitch voltage of the pitch motor by u=v×f, it may be determined whether the pitch drive will fail based on the magnitude relation of the theoretical pitch voltage and the actual pitch voltage and the magnitude relation of the actual pitch speed of the pitch motor and the given pitch speed. For example, it may be determined first whether the actual pitch voltage is greater than N times the theoretical pitch voltage (U1 > n×u, U1 representing the actual pitch voltage) for a threshold time. Here, N may be a real number greater than 1 (e.g., without limitation, n=2). The threshold time may be, for example, but not limited to, 5s. In fact, when U1>2U reaches 5s (i.e., the actual pitch voltage of the pitch motor continues to increase), the flux of the pitch drive may be considered to decrease. Thereafter, when the actual pitch voltage is greater than N times the theoretical pitch voltage for a threshold time, it may be determined whether the actual pitch speed of the pitch motor reaches the given pitch speed. By determining whether the actual pitch speed of the pitch motor reaches a given pitch speed, it can be determined whether the pitch motor is started normally. If the actual pitch speed reaches the given pitch speed, it may be determined that the pitch drive will fail. In other words, if the actual pitch speed reaches the given pitch speed, it is indicated that the pitch motor is started normally. However, since the actual pitch voltage of the pitch motor increases more and continues to increase at this time, indicating that the flux of the pitch drive has decreased, it may ultimately be assumed that the pitch drive will fail. More specifically, the purpose of detecting the pitch speed is to improve the accuracy of pitch motor voltage consistency determination and pitch drive failure warning, which is essentially to verify that the flux of the pitch motor is reduced and that the voltage output by the pitch drive is increased.

Alternatively, the theoretical pitch voltage corresponding to the actual pitch speed may be obtained according to the actual pitch speed of the pitch motor and the linear relationship obtained by fitting the historical pitch voltage of the pitch motor and the historical pitch speed. For example, the linear relationship obtained by fitting the historical pitch voltage and the historical pitch speed of the pitch motor may be: u=a+b X, and thus, the obtained actual pitch speed of the pitch motor is brought into the linear equation to obtain a theoretical pitch voltage of the pitch motor at the actual pitch speed, and then, based on a magnitude relation between the theoretical pitch voltage and the actual pitch voltage, it is determined whether the pitch drive will fail. For example, it may be determined first at this time whether the actual pitch voltage is greater than N times the theoretical pitch voltage for a threshold time. As described above, N may be a real number greater than 1 (e.g., without limitation, n=2). The threshold time may be, for example, but not limited to, 5s. Thereafter, when the actual pitch voltage is greater than N times the theoretical pitch voltage for a threshold time, it may be determined that the pitch drive will fail.

According to embodiments of the present disclosure, it may be determined whether the output information of the pitch drive contains pitch motor flux information prior to calculating the theoretical pitch voltage of the pitch motor. If the output information of the pitch drive includes pitch motor magnetic flux information, it may be determined whether the pitch motor magnetic flux is saturated, and when the pitch motor magnetic flux is saturated, it may be determined that the pitch drive will fail. Generally, if phi exceeds 110%, the magnetic circuit begins to saturate, and more than 120% is already supersaturated. When the magnetic circuit is in a severe saturation state, the peak exciting current of the magnetic circuit can exceed a plurality of times of rated current, and the output voltage of the magnetic circuit can also rise, so that the overcurrent of the pitch drive trips.

In addition, the torque boost of the pitch drive may be obtained prior to calculating the theoretical pitch voltage of the pitch motor, and when the torque boost of the pitch drive exceeds a preset threshold, it may be determined that the pitch drive will fail. For example, the upper limit value of the torque lifting amount is generally 10%, but is not limited thereto.

In addition, when it is determined that the pitch drive will fail, fault warning information indicating that the pitch drive will fail may be provided to a main controller of the wind turbine. However, the present disclosure is not limited thereto. For example, the fault warning information may be processed directly by the pitch controller.

According to the fault early warning method of the pitch drive, starting from the working principle of the pitch drive (namely the voltage compensation/torque compensation), the fault early warning can be carried out on the pitch drive 25-30 seconds in advance. During this time, there is enough time to complete the anti-seize operation and control.

Examples of fault warning methods of a pitch drive according to embodiments of the present disclosure are described below with reference to fig. 4 and 5.

Fig. 4 is a flowchart illustrating an example of a fault warning method of a pitch drive according to an embodiment of the present disclosure.

Referring to fig. 4, in step S401, a current shaft pitch motor voltage (i.e., an actual pitch voltage of the pitch motor) and a blade pitch speed (i.e., an actual pitch speed of the pitch motor) may be collected. As described above, the shaft may correspond to a blade. Optionally, the three blades correspond to a shaft respectively, a variable pitch cabinet is arranged on each shaft, and a variable pitch controller is arranged in each variable pitch cabinet. In addition, each shaft is also provided with a pitch drive and a pitch motor. As described above, the fault warning method may be performed by the pitch controller.

In step S402, the operating frequency of the pitch drive may be collected, and a theoretical pitch voltage u=v×f of the pitch motor is calculated; v is the blade pitch speed (i.e., the actual pitch speed of the pitch motor) and f is the operating frequency of the pitch drive. Table 1 below shows the correspondence between the theoretical pitch voltage of the pitch motor and the operating frequency, pitch speed.

TABLE 1

In step S403, it is determined whether the actual pitch voltage U1 of the pitch motor is greater than N (e.g., n=2) times U for a predetermined time. If U1> N U, it may be initially determined that the pitch drive flux is decreasing and that a fault will occur. On the other hand, if U1 is equal to or less than n×u, or U1> n×u does not last for a predetermined time, it may be considered that the pitch drive does not fail, and the failure early warning method is exited.

When U1> N x U lasts for a predetermined time, in step S404, it may be determined whether the actual pitch speed of the pitch motor reaches a given pitch speed.

If the actual pitch speed of the pitch motor reaches the given pitch speed, then in step S405, it may be determined that the pitch drive will fail. As described above, if the actual pitch speed reaches a given pitch speed, it is indicated that the pitch motor is started normally. However, since it has been determined that the pitch drive flux decreases, it may eventually be assumed that the pitch drive will fail if the actual pitch speed reaches a given pitch speed. On the other hand, if the actual pitch speed of the pitch motor does not reach the given pitch speed, the pitch drive can be finally determined not to be faulty, and the fault early warning step is exited.

According to an embodiment of the present disclosure, when it is determined in step S405 that the pitch drive will fail, failure warning information may be provided to, for example, a main controller of the wind turbine generator set to process the failure warning information. However, the present disclosure is not limited thereto. The fault early warning information can also be directly processed by the variable pitch controller.

Fig. 5 is a flowchart illustrating another example of a fault warning method of a pitch drive according to an embodiment of the present disclosure.

Referring to fig. 5, in step S501, a current shaft pitch motor voltage (i.e., an actual pitch voltage of the pitch motor) and a blade pitch speed (i.e., an actual pitch speed of the pitch motor) may be collected.

Then, in step S502, the theoretical pitch voltage of the pitch motor may be calculated by the equation u=a+b×x, where U represents the theoretical pitch voltage of the pitch motor, X represents the actual pitch speed of the pitch motor, B represents the first coefficient, and a represents the second coefficient. Here, the linear relationship between the historical theoretical pitch voltage and the historical pitch speed of the pitch motor may be determined by performing curve fitting on the historical theoretical pitch voltage and the historical pitch speed through an experimental method, that is, the equation u=a+b×x above, where a and B are a first coefficient and a second coefficient obtained through curve fitting, respectively. For example, curve fitting may be performed with a given pitch speed as shown in table 1 as a historical pitch speed and a theoretical pitch voltage as shown in table 1 as a historical theoretical pitch voltage. In this case, alternatively, a= -35.33853004, b= 44.50517005 may be obtained.

Next, in step S503, it is determined whether the actual pitch voltage U1 of the pitch motor is greater than N (e.g., n=2) times U for a predetermined time. If U1> N x U, then in step S504, it may be determined that the pitch drive will fail. On the other hand, if U1 is equal to or less than n×u, or U1> n×u does not last for a predetermined time, it may be considered that the pitch drive does not fail, and the failure early warning method is exited.

As described above, when it is determined that the pitch drive will fail in step S504, the failure warning information may be provided to, for example, a main controller of the wind turbine generator set to process the failure warning information. However, the present disclosure is not limited thereto. The fault early warning information can also be directly processed by the variable pitch controller.

A fault handling method of a pitch drive according to an embodiment of the present disclosure is described in detail below with reference to fig. 6 to 8.

Fig. 6 is a flowchart illustrating a fault handling method of a pitch drive according to an embodiment of the present disclosure.

According to embodiments of the present disclosure, the fault handling method may be run in a main controller or other controller that may be in a wind turbine. However, the disclosure is not limited thereto, and the fault handling method may also be run in a controller of a wind farm or in any other controller capable of communicating with a wind park.

Referring to fig. 6, in step S601, the output of the pitch drive is adjusted in response to determining that the pitch drive will fail by the failure warning method as described above. For example, when fault warning information is received, the output of the pitch drive may be adjusted. Here, adjusting the output of the pitch drive may include pausing the output of the pitch drive and adjusting the output of the pitch drive by reducing a given pitch speed provided to the pitch drive.

Then, in step S602, after a predetermined time elapses for adjusting the output of the pitch drive, the output of the pitch drive is controlled to return to normal. For example, the predetermined time may be set to 3s to 10s, but is not limited thereto.

Optionally, the fault handling method may further include the steps of: in response to determining that the pitch drive will fail by the failure warning method as described above, a determination is made as to whether the risk is avoidable. When it is determined that the risk can be circumvented, the output of the pitch drive is adjusted. In particular, the rotational speed of the wind park and the wind speed at the location of the wind park may be detected first, and then it may be determined whether the detected rotational speed is less than a threshold rotational speed and whether the detected wind speed is less than a threshold wind speed. When it is determined that the detected rotational speed is less than the threshold rotational speed and the detected wind speed is less than the threshold wind speed, determining the risk may circumvent. However, if it is determined that the risk is not avoidable, the fault handling method may be exited for control of the wind turbine by other control strategies (e.g., without limitation, controlling a wind turbine shutdown).

Optionally, the fault handling method may further include the steps of: controlling the yaw preset angle of the wind driven generator in response to determining that the pitch drive will fail by the failure early warning method as described above; detecting whether the rotating speed of the wind generating set is reduced; and when the rotation speed of the wind generating set is detected to be reduced, adjusting the output of the pitch drive. However, if no reduction in rotational speed of the wind turbine is detected, the fault handling method may be exited to control the wind turbine via other control strategies (e.g., without limitation, to control the wind turbine shutdown).

Optionally, the fault handling method may further include the steps of: determining, during the predetermined time, whether the angles of the individual blades are consistent in response to adjusting the output of the pitch drive; and controlling the shutdown of the wind generating set in response to determining that the angles of the blades are inconsistent. Specifically, the angle of the first blade at the time when the determined pitch drive will fail may be set as the reference angle value, wherein the first blade is the blade corresponding to the determined pitch drive that will fail. Next, the sum of the reference angle value and the additional angle value may be taken as an angle upper limit value, and the difference between the reference angle value and the additional angle value may be taken as an angle lower limit value. Then, it is monitored during the predetermined time whether the angle of the other blade exceeds an angle threshold range defined by an angle upper limit value and an angle lower limit value. If the angle of any blade is monitored to exceed the angle threshold range, the inconsistent angle of each blade can be determined, so that the fault processing method is exited, and the shutdown of the wind generating set is controlled.

According to the fault processing method of the pitch drive, which is disclosed by the embodiment of the invention, the operation of restarting the pitch drive after power failure is not needed, and the output time of the pitch drive can be adjusted, so that the safety influence on a wind generating set is small, and the problem of brake band-type brake abrasion caused by restarting the pitch drive after power failure is avoided. On the other hand, by performing yaw of the side wind after determining that the pitch drive will fail, such that the wind force received by the blades of the wind turbine generator is reduced, the rotational speed is reduced, and then performing operation control such as adjusting the output of the determined pitch drive that will fail and then restoring the normal output thereof, the safety of the wind turbine generator can be further protected. In addition, by judging whether the angles of the blades are consistent, the load increase of the wind generating set caused by inconsistent angles of the three blades after the triggering failure of the pitch drive is reduced. Further, by adjusting the output of the pitch drive by reducing the given pitch speed provided to the pitch drive, rather than suspending the output of the pitch drive, delays caused by powering down the pitch drive, or suspending the operation of the pitch drive, may be reduced.

An example of a fault handling method of a pitch drive according to an embodiment of the present disclosure is described below with reference to fig. 7 and 8.

Fig. 7 is a flowchart illustrating an example of a fault handling method of a pitch drive according to an embodiment of the present disclosure.

Referring to fig. 7, in response to receiving the fault warning information, the rotational speed of the wind turbine and the wind speed at the location of the wind turbine are detected in step S701.

In step S702, it is determined whether the risk can be circumvented based on the rotational speed of the wind park and the wind speed at the location of the wind park. As described above, when determining whether the detected rotational speed is less than the threshold rotational speed and whether the detected wind speed is less than the threshold wind speed, determining the risk may be circumvented.

When it is determined that the risk can be circumvented, in step S703, the output of the pitch drive is suspended. And stopping the operation of the pitch motor by suspending the output of the determined pitch drive which will fail, so as to wait for the elimination of the condition which causes the fault early warning. However, if it is determined that the risk is not avoidable, the fault handling method may be exited for control of the wind turbine by other control strategies (e.g., without limitation, controlling a wind turbine shutdown).

In step S704, the angle of the first blade at the time when it is determined that the pitch drive will fail is recorded as a reference angle value. As described above, the first blade is the blade corresponding to the determined pitch drive that will fail.

In step S705, it is monitored during a predetermined time whether the angle of the other blade exceeds the pitch angle threshold range. Here, the pitch angle range threshold value may be determined by taking the sum of the reference angle value and the additional angle value as the angle upper limit value and taking the difference between the reference angle value and the additional angle value as the angle lower limit value. The additional angle value may be, for example, but not limited to, 3.5 degrees. Specifically, if it is determined that the angle of the first blade (i.e., the reference angle value) at the time when the pitch drive will fail is 5.5 degrees, the pitch angle upper limit value of the other two blades is 5.5+3.5=8 degrees, and the pitch angle lower limit value is 5.5-3.5=2 degrees. Therefore, the other two blades can be subjected to pitch adjustment within the range of the pitch adjustment angle threshold value of 2-8 degrees, and the rotating speed of the wind generating set can be ensured not to overspeed.

If no blade angle is detected to be outside the pitch angle threshold range, in step S706, the output of the pitch drive is restored, thereby restarting the pitch control of the corresponding blade. However, if the angle of any blade is detected to be outside the angle threshold range, the fault handling method may be exited and the wind turbine generator set may be controlled to stop.

Fig. 8 is a flowchart illustrating another example of a fault handling method of a pitch drive according to an embodiment of the present disclosure.

Referring to fig. 8, in step S801, a yaw preset angle of a wind turbine is controlled in response to receiving fault warning information.

In step S802, it is detected whether the rotational speed of the wind turbine generator system has dropped.

When a decrease in the rotational speed of the wind turbine generator system is detected, the output of the pitch drive is suspended in step S803. However, if no reduction in rotational speed of the wind turbine is detected, the fault handling method may be exited to control the wind turbine via other control strategies (e.g., without limitation, to control the wind turbine shutdown).

Next, in step S804, the angle of the first blade at the time when it is determined that the pitch drive will fail is recorded as a reference angle value. As described above, the first blade is the blade corresponding to the determined pitch drive that will fail.

In step S805, it is monitored during a predetermined time whether the angle of the other blade exceeds the pitch angle threshold range. As described above, the pitch angle range threshold value may be determined by taking the sum of the reference angle value and the additional angle value as the angle upper limit value and taking the difference between the reference angle value and the additional angle value as the angle lower limit value.

If no blade angle is detected to be outside the pitch angle threshold range, in step S806, the output of the pitch drive is restored, thereby restarting the pitch control of the corresponding blade. However, if the angle of any blade is detected to be outside the angle threshold range, the fault handling method may be exited and the wind turbine generator set may be controlled to stop.

Fig. 9 is a block diagram illustrating a fault warning apparatus of a pitch drive according to an embodiment of the present disclosure.

As described above, three blades of the wind power generation set correspond to one shaft each, each shaft having a pitch controller, a pitch drive, and a pitch motor. Accordingly, each pitch controller may be provided with a failure warning device of the pitch drive according to embodiments of the present disclosure. However, the present disclosure is not limited thereto, and the fault warning device of the pitch drive according to the embodiments of the present disclosure may be provided in a main controller or in other controllers of the wind turbine generator set.

Referring to fig. 9, the fault early-warning apparatus 900 may include a voltage calculation unit 910, a voltage acquisition unit 920, and a fault early-warning unit 930. The voltage calculating unit 910 may calculate a theoretical pitch voltage of the pitch motor based on the operation data of the pitch motor. The operational data of the pitch motor may comprise an actual pitch speed of the pitch motor and/or an operational frequency of the pitch motor. The voltage acquisition unit 920 may acquire an actual pitch voltage of the pitch motor. The fault early warning unit 930 may determine whether the pitch drive will fail based on the theoretical pitch voltage and the actual pitch voltage.

Specifically, the voltage calculation unit 910 may calculate the product of the actual pitch speed of the pitch motor and the operating frequency of the pitch motor as the theoretical pitch voltage of the pitch motor. That is, u=v×f, where U represents the theoretical pitch voltage of the pitch motor, v represents the actual pitch speed of the pitch motor, and f represents the operating frequency of the pitch motor. Alternatively, the voltage calculating unit 910 may obtain the theoretical pitch voltage corresponding to the actual pitch speed according to the actual pitch speed of the pitch motor and the linear relationship obtained by fitting the historical pitch voltage of the pitch motor and the historical pitch speed. That is, u=a+b×x, where U represents the theoretical pitch voltage of the pitch motor, X represents the actual pitch speed of the pitch motor, and a and B are the first coefficient and the second coefficient obtained by fitting.

In the case of calculating the theoretical pitch voltage of the pitch motor by u=v×f, the fault early warning unit 930 may determine whether the pitch drive will fail based on the magnitude relation of the theoretical pitch voltage and the actual pitch voltage and the magnitude relation of the actual pitch speed of the pitch motor and the given pitch speed. More specifically, the fault early warning unit 930 may determine whether the actual pitch voltage is greater than N times the theoretical pitch voltage for a threshold time, where N is a real number greater than 1. When the actual pitch voltage is greater than N times the theoretical pitch voltage for a threshold time, the fault pre-warning unit 930 may determine whether the actual pitch speed of the pitch motor reaches the given pitch speed. If the actual pitch speed reaches the given pitch speed, the fault early warning unit 930 may determine that the pitch drive will fail, thereby sending early warning information for early warning.

Alternatively, in the case of calculating the theoretical pitch voltage of the pitch motor by u=a+b×x, the fault early-warning unit 930 may determine whether the pitch drive will fail based on the magnitude relation of the theoretical pitch voltage and the actual pitch voltage. More specifically, the fault early warning unit 930 may determine whether the actual pitch voltage is greater than N times the theoretical pitch voltage for a threshold time, where N is a real number greater than 1. When the actual pitch voltage is greater than N times the theoretical pitch voltage for a threshold time, the fault early warning unit 930 may determine that the pitch drive will fail.

According to embodiments of the present disclosure, the fault early warning unit 930 may determine whether the output information of the pitch drive contains the pitch motor flux information before calculating the theoretical pitch voltage of the pitch motor. If the output information of the pitch drive includes the pitch motor magnetic flux information, the fault early warning unit 930 may determine whether the pitch motor magnetic flux is saturated, and when the pitch motor magnetic flux is saturated, the fault early warning unit 930 may determine that the pitch drive will fail. In addition, the fault early warning unit 930 may acquire a torque lifting amount of the pitch drive before calculating the theoretical pitch voltage of the pitch motor, and when the torque lifting amount of the pitch drive exceeds a preset threshold, the fault early warning unit 930 may determine that the pitch drive will fail. In addition, when it is determined that the pitch drive will fail, the failure warning unit 930 may provide failure warning information indicating that the pitch drive will fail to the main controller of the wind turbine.

Fig. 10 is a block diagram illustrating a fault handling apparatus of a pitch drive according to an embodiment of the present disclosure.

As described above, three blades of the wind power generation set correspond to one shaft each, each shaft having a pitch controller, a pitch drive, and a pitch motor. Accordingly, each pitch controller may be provided with a fault handling arrangement of the pitch drive according to embodiments of the present disclosure. However, the present disclosure is not limited thereto, and the fault handling device of the pitch drive according to the embodiments of the present disclosure may be provided in the main controller of the wind power generation set or in other controllers.

Referring to fig. 10, a fault handling apparatus 1000 of a pitch drive according to an embodiment of the present disclosure may include an output adjustment unit 1010 and an output recovery unit 1020. The output adjustment unit 1010 may adjust the output of the pitch drive in response to a failure warning device as described above determining that the pitch drive will fail. Adjusting the output of the pitch drive may include pausing the output of the pitch drive and adjusting the output of the pitch drive by reducing a given pitch speed provided to the pitch drive. The output recovery unit 1020 may control the output of the pitch drive to be recovered to normal after a predetermined time.

In particular, in response to determining that the pitch drive will fail by the failure warning device as described above, the output adjustment unit 1010 may determine whether the risk may be circumvented. When it is determined that the risk may be circumvented, the output adjustment unit 1010 may adjust the output of the pitch drive. More specifically, the output adjustment unit 1010 may first detect the rotational speed of the wind turbine and the wind speed at the location of the wind turbine, and then determine whether the detected rotational speed is less than a threshold rotational speed and determine whether the detected wind speed is less than a threshold wind speed. When it is determined that the detected rotational speed is less than the threshold rotational speed and the detected wind speed is less than the threshold wind speed, the output adjustment unit 1010 determines that the risk may be circumvented.

Alternatively, in response to determining that the pitch drive will fail by the failure warning device as described above, the output adjustment unit 1010 may control the wind turbine to yaw by a preset angle, detect whether the rotational speed of the wind turbine is decreasing, and adjust the output of the pitch drive when the rotational speed of the wind turbine is detected to decrease.

Alternatively, in response to adjusting the output of the pitch drive, the output adjustment unit 1010 may determine whether the angles of the individual blades are consistent during the predetermined time; and controlling the shutdown of the wind generating set in response to determining that the angles of the blades are inconsistent. Further, the output adjustment unit 1010 may set the angle of the first blade at the time when the determined pitch drive will fail as the reference angle value, wherein the first blade is the blade corresponding to the determined pitch drive that will fail. Next, the output adjustment unit 1010 may take the sum of the reference angle value and the additional angle value as an angle upper limit value, and the difference between the reference angle value and the additional angle value as an angle lower limit value. Subsequently, the output adjustment unit 1010 may monitor whether the angle of the other blade exceeds an angle threshold range defined by an angle upper limit value and an angle lower limit value during the predetermined time. If the angle of any blade is monitored to be outside the angle threshold range, the output adjustment unit 1010 may determine that the angles of the respective blades are inconsistent, thereby controlling the wind turbine to stop.

Referring to FIG. 11, a controller 1100 of a wind turbine may be, but is not limited to, a pitch controller, a master controller of a wind turbine, or the like, in accordance with embodiments of the present disclosure. As described above, three blades of the wind power generation set correspond to one shaft each, each shaft having a pitch controller, a pitch drive, and a pitch motor. The controller 1100 of a wind turbine generator system according to embodiments of the present disclosure may include a processor 1110 and a memory 1120. The processor 1110 may include, but is not limited to, a Central Processing Unit (CPU), a Digital Signal Processor (DSP), a microcomputer, a Field Programmable Gate Array (FPGA), a system on a chip (SoC), a microprocessor, an Application Specific Integrated Circuit (ASIC), and the like. The memory 1120 stores a computer program to be executed by the processor 1110. Memory 1120 includes high-speed random access memory and/or nonvolatile computer readable storage media. When the processor 1110 executes the computer program stored in the memory 1120, a failure warning method of the pitch drive or a failure processing method of the pitch drive as described above may be implemented.

Alternatively, the controller 1100 may communicate with other components in the wind farm in a wired/wireless communication manner, and may also communicate with other devices in the wind farm in a wired/wireless communication manner. In addition, the controller 1100 may communicate with devices external to the wind farm in a wired/wireless communication.

The fault early warning method of the pitch drive and the fault handling method of the pitch drive according to the embodiments of the present disclosure may be written as computer programs and stored on a computer-readable storage medium. When the computer program is executed by a processor, the fault early warning method of the pitch drive or the fault processing method of the pitch drive as described above can be realized. Examples of the computer readable storage medium include: read-only memory (ROM), random-access programmable read-only memory (PROM), electrically erasable programmable read-only memory (EEPROM), random-access memory (RAM), dynamic random-access memory (DRAM), static random-access memory (SRAM), flash memory, nonvolatile memory, CD-ROM, CD-R, CD + R, CD-RW, CD+RW, DVD-ROM, DVD-R, DVD + R, DVD-RW, DVD+RW, DVD-RAM, BD-ROM, BD-R, BD-R LTH, BD-RE, blu-ray or optical disk storage, hard Disk Drives (HDD), solid State Disks (SSD), card memory (such as multimedia cards, secure Digital (SD) cards or ultra-fast digital (XD) cards), magnetic tape, floppy disks, magneto-optical data storage, hard disks, solid state disks, and any other means configured to store computer programs and any associated data, data files and data structures in a non-transitory manner and to provide the computer programs and any associated data, data files and data structures to a processor or computer to enable the processor or computer to execute the programs. In one example, the computer program and any associated data, data files, and data structures are distributed across networked computer systems such that the computer program and any associated data, data files, and data structures are stored, accessed, and executed in a distributed manner by one or more processors or computers.

Although a few embodiments of the present disclosure have been shown and described, it would be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the disclosure, the scope of which is defined in the claims and their equivalents.

Claims

1. The fault early warning method for the variable pitch drive is characterized by comprising the following steps of:

calculating a theoretical variable pitch voltage of the variable pitch motor based on the operation data of the variable pitch motor;

acquiring actual variable pitch voltage of a variable pitch motor; and

determining whether the pitch drive will fail based on the theoretical pitch voltage and the actual pitch voltage;

wherein the operation data comprise the actual pitch speed of the pitch motor and the operation frequency of the pitch motor;

wherein, the step of calculating the theoretical pitch voltage of the pitch motor comprises: calculating the product of the actual pitch speed of the pitch motor and the running frequency of the pitch motor to serve as the theoretical pitch voltage of the pitch motor;

wherein, the step of calculating the theoretical pitch voltage of the pitch motor further comprises:

obtaining a theoretical variable pitch voltage corresponding to the actual variable pitch speed according to the actual variable pitch speed of the variable pitch motor and a linear relation obtained by fitting the historical variable pitch voltage of the variable pitch motor with the historical variable pitch speed;

Wherein the step of determining whether the pitch drive will fail based on the theoretical pitch voltage and the actual pitch voltage comprises: based on the magnitude relation of the theoretical pitch voltage and the actual pitch voltage and the magnitude relation of the actual pitch speed of the pitch motor and the given pitch speed, it is determined whether the pitch drive will fail.

2. The fault alerting method of claim 1, wherein the step of determining whether the pitch drive will fail comprises:

determining whether the actual pitch voltage is greater than N times of the theoretical pitch voltage for a threshold time, wherein N is a real number greater than 1;

when the actual pitch voltage is greater than N times of the theoretical pitch voltage for a threshold time, determining whether the actual pitch speed of the pitch motor reaches a given pitch speed;

if the actual pitch speed reaches the given pitch speed, it is determined that the pitch drive will fail.

3. The fault warning method of claim 1, wherein the step of determining whether the pitch drive will fail based on the theoretical pitch voltage and the actual pitch voltage comprises: based on the magnitude relation of the theoretical pitch voltage and the actual pitch voltage, it is determined whether the pitch drive will fail.

4. The fault alerting method of claim 3, wherein the step of determining whether the pitch drive will fail comprises:

when the actual pitch voltage is greater than N times the theoretical pitch voltage for a threshold time, it is determined that the pitch drive will fail.

5. The fault pre-warning method of claim 1, further comprising:

before calculating a theoretical pitch voltage of the pitch motor, it is determined whether the magnetic flux of the pitch motor is saturated based on the pitch motor magnetic flux information contained in the output information of the pitch drive, and it is determined that the pitch drive will fail in response to the magnetic flux of the pitch motor being saturated.

6. The fault pre-warning method of claim 1, further comprising:

before calculating a theoretical pitch voltage of the pitch motor, a torque boost amount of the pitch drive is obtained, and in response to the torque boost amount of the pitch drive exceeding a preset threshold, it is determined that the pitch drive will fail.

7. A method of fault handling for a pitch drive, the method comprising:

adjusting an output of the pitch drive in response to determining that the pitch drive will fail by the failure warning method of any one of claims 1 to 6; and

after a predetermined time, the output of the pitch drive is controlled to resume normal.

8. The fault handling method of claim 7, wherein the fault handling method further comprises:

in response to determining that the pitch drive will fail by the failure early warning method of any one of claims 1 to 6, determining whether a risk is avoidable;

in response to determining that the risk evacuable, the step of adjusting the output of the pitch drive is performed.

9. The fault handling method of claim 8, wherein the step of determining whether the risk is avoidable comprises:

detecting the rotating speed of the wind generating set and the wind speed of the position of the wind generating set;

determining whether the detected rotational speed is less than a threshold rotational speed, and determining whether the detected wind speed is less than a threshold wind speed;

in response to determining that the detected rotational speed is less than the threshold rotational speed and the detected wind speed is less than the threshold wind speed, determining that the risk may be circumvented.

10. The fault handling method of claim 7, wherein the fault handling method further comprises:

controlling the wind power generator to yaw a preset angle in response to determining that the pitch drive will fail by the failure early warning method according to any one of claims 1 to 6;

detecting whether the rotating speed of the wind generating set is reduced;

in response to detecting a decrease in rotational speed of the wind park, the step of adjusting the output of the pitch drive is performed.

11. The fault handling method of claim 7, wherein the output of the pitch drive is adjusted: including suspending the output of the pitch drive.

12. The fault handling method of claim 7, wherein adjusting the output of the pitch drive comprises: the output of the pitch drive is adjusted by reducing the given pitch speed provided to the pitch drive.

13. The fault handling method of claim 7, wherein the fault handling method further comprises:

determining, during the predetermined time, whether the angles of the individual blades are consistent in response to adjusting the output of the pitch drive;

and controlling the shutdown of the wind generating set in response to determining that the angles of the blades are inconsistent.

14. The fault handling method of claim 13, wherein the step of determining whether the angles of the respective blades are consistent during the predetermined time period comprises:

setting the angle of a first blade at the moment when the determined pitch drive will fail as a reference angle value, wherein the first blade is a blade corresponding to the determined pitch drive which will fail;

taking the sum of the reference angle value and the additional angle value as an angle upper limit value, and taking the difference between the reference angle value and the additional angle value as an angle lower limit value;

monitoring during the predetermined time whether the angle of the other blade exceeds an angle threshold range defined by an angle upper limit value and an angle lower limit value;

in response to monitoring that the angle of any of the blades exceeds the angle threshold range, an angular inconsistency of each blade is determined.

15. A fault early warning device for a pitch drive, the fault early warning device comprising:

a voltage calculation unit configured to calculate a theoretical pitch voltage of the pitch motor based on operation data of the pitch motor;

a voltage acquisition unit configured to acquire an actual pitch voltage of the pitch motor; and

a fault early warning unit configured to determine whether the pitch drive will fail based on the theoretical pitch voltage and the actual pitch voltage;

the voltage calculation unit is further configured to calculate the product of the actual pitch speed of the pitch motor and the running frequency of the pitch motor as a theoretical pitch voltage of the pitch motor;

the voltage calculation unit is further configured to obtain a theoretical pitch voltage corresponding to the actual pitch speed according to the actual pitch speed of the pitch motor and a linear relation obtained by fitting the historical pitch voltage and the historical pitch speed of the pitch motor;

the fault early warning unit is further configured to determine whether the pitch drive will fail based on the magnitude relation between the theoretical pitch voltage and the actual pitch voltage and the magnitude relation between the actual pitch speed of the pitch motor and the given pitch speed.

16. A fault handling device for a pitch drive, the fault handling device comprising:

an output adjustment unit configured to adjust an output of the pitch drive in response to the failure warning device of claim 15 determining that the pitch drive will fail; and

and an output restoration unit configured to control the output of the pitch drive to be restored to normal after a predetermined time.

17. A computer readable storage medium storing a computer program, wherein the computer program, when executed by a processor, implements the failure warning method of a pitch drive according to any one of claims 1 to 6 or the failure handling method of a pitch drive according to any one of claims 7 to 14.

18. A controller for a wind turbine generator system, the controller comprising:

a processor; and

a memory storing a computer program which, when executed by a processor, implements the fault warning method of a pitch drive as claimed in any one of claims 1 to 6 or the fault handling method of a pitch drive as claimed in any one of claims 7 to 14.