Variable pitch system encoder fault processing method, device, equipment and medium

Abstract

The invention discloses a variable-pitch system encoder fault processing method, device and equipment and a medium, and the method comprises the steps: determining the number of rotation turns of a target variable-pitch motor corresponding to a target blade in a variable-pitch system within a preset time period, and determining the number of rotation turns of a target encoder corresponding to the target blade in the variable-pitch system within the preset time period based on an output signal of the target encoder corresponding to the target blade in the variable-pitch system within the preset time period; and determining the number of times of angle sudden change of the target blade in a preset duration, comparing the number of rotation turns with the number of times of angle sudden change, and determining that the target encoder has multi-turn signal abnormality in response to the consistency of the number of rotation turns and the number of times of angle sudden change. According to the embodiment of the invention, the multi-turn signal abnormity of the encoder of the variable pitch system is diagnosed and analyzed according to the operation characteristics of the variable pitch system, so that the problem of inaccurate diagnosis result caused by uncertain single-turn signal change amplitude, uncertain change frequency, uncertain dwell time and the like in the traditional diagnosis method is effectively solved; and the detection precision is improved.

Description

Technical Field

[0001] The present application belongs to the field of wind power generation technology, and in particular, relates to a method, device, equipment and medium for handling faults of a pitch system encoder. Background Art

[0002] A wind turbine is a device that converts wind energy into electrical energy. Wind energy is converted into electrical energy by driving the main shaft, speed increaser, and generator set through the impeller, and the electrical energy generated by the wind turbine is transmitted to the power grid through grid-connected control. Among them, the variable pitch system plays a vital role in tracking the maximum power of the wind turbine and ensuring the safe shutdown of the wind turbine. At present, the control method of the variable pitch system of a wind turbine is mainly as follows: the main control system of the wind turbine detects the actual speed value of the wind turbine, and sets the target speed value according to the characteristics of the unit model. The target angle value of the blade is output by performing PID calculation on the deviation between the target speed value and the actual speed value. After the variable pitch system receives the target angle value issued by the main control system, it uses the absolute value signal of the encoder to collect the change of the blade angle value, and forms a closed-loop PID negative feedback control with the variable pitch motor, thereby controlling the running speed and direction of the variable pitch motor. Among them, the variable pitch motor meshes with the inner gear ring of the impeller through the driving gear, so the blade angle value can be directly controlled.

[0003] The encoder in the pitch system usually uses a photoelectric encoder. Since the transmission from the motor side to the blade side of the pitch system is relatively large, a multi-turn encoder is generally used in the pitch system. The counting principle of the multi-turn encoder is: when the single turn rotates one circle, the number of multi-turns increases by 1; when the number of multi-turns reaches the full range, the encoder value becomes 0 and the counting starts again. In the pitch system, the blade angle value is determined based on the multi-turn signal and the single-turn signal of the multi-turn encoder.

[0004] During the operation of a wind turbine, due to various abnormal reasons, the encoder corresponding to the blade may have multi-turn signal abnormalities. After the encoder has multi-turn signal abnormalities, as the single-turn value changes, the multi-turn value is no longer accumulated, so that the blade angle value finally determined based on the signal output by the encoder is always at a smaller angle data. This will cause the positions of the three blades detected by the wind turbine to be different, causing the wind turbine to trigger a fault and shut down. Moreover, since the blade angle value is always at a smaller angle data, the wind turbine will trigger the limit during the retraction process. In addition, it may also cause the driver to restart multiple times. In order to avoid the risk of blade jamming, the general protection method of a wind turbine is to detect that the angle of a blade is less than a certain angle, and after the other two blades are retracted, the pitch controller will restart the driver to try to retract the blade to a safe position. Moreover, due to the failure of the encoder, the incremental signal and the calculated pitch motor speed value will no longer be used as a reference.

[0005] In order to reduce the adverse effects caused by the abnormal multi-turn signal of the encoder, it is necessary to troubleshoot the encoder. The existing method of troubleshooting or detecting encoder faults is generally to perform statistical analysis on the encoder's usage data to determine whether a multi-turn signal abnormality has occurred. However, due to different encoder types, different retracting speeds, different models and variable pitch transmission ratios, different data collection cycles, etc., the data waveform will be affected, making parameter setting more difficult. Therefore, the detection accuracy obtained through statistical analysis is low. Summary of the invention

[0006] The embodiments of the present application provide a pitch system encoder fault handling method, device, equipment, medium and program, which can accurately identify multi-turn signal anomalies of an encoder in a pitch system.

[0007] In a first aspect, an embodiment of the present application provides a method for handling a pitch system encoder fault, comprising:

[0008] Determine the number of rotations of a target pitch motor corresponding to a target blade in a pitch system within a preset time period;

[0009] Determine the number of angle mutations of the target blade within the preset time length based on an output signal of a target encoder corresponding to the target blade in the pitch system within the preset time length;

[0010] Compare the number of rotations with the number of angle mutations;

[0011] In response to the fact that the number of rotations is consistent with the number of angle mutations, it is determined that the target encoder has a multi-turn signal anomaly.

[0012] In a second aspect, an embodiment of the present application provides a pitch system encoder fault processing device, comprising:

[0013] A first determination module is used to determine the number of rotations of a target pitch motor corresponding to a target blade in a pitch system within a preset time period;

[0014] A second determination module is used to determine the number of angle mutations of the target blade within a preset time length based on an output signal of a target encoder corresponding to the target blade in the pitch control system within a preset time length;

[0015] A comparison module, used for comparing the number of rotations with the number of angle mutations;

[0016] The abnormality determination module is used to determine that a target encoder corresponding to a target blade in a variable pitch system has a multi-turn signal abnormality in response to the number of rotations being consistent with the number of angle mutations.

[0017] In a third aspect, an embodiment of the present application provides an electronic device, the electronic device comprising: a processor and a memory storing computer program instructions;

[0018] When the processor executes the computer program instructions, the pitch system encoder fault processing method of the first aspect is implemented.

[0019] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium having computer program instructions stored thereon. When the computer program instructions are executed by a processor, the pitch system encoder fault handling method of the first aspect is implemented.

[0020] In a fifth aspect, an embodiment of the present application provides a computer program product. When the instructions in the computer program product are executed by a processor of an electronic device, the electronic device executes the pitch system encoder fault handling method as shown by the first party.

[0021] The present application discloses a method, device, equipment and medium for handling faults of a pitch system encoder, the method comprising: determining the number of rotations of a target pitch motor corresponding to a target blade in the pitch system within a preset time length, determining the number of angle mutations of the target blade within a preset time length based on the output signal of a target encoder corresponding to the target blade in the pitch system within a preset time length, comparing the number of rotations with the number of angle mutations, and determining that the target encoder has a multi-turn signal anomaly in response to the number of rotations being consistent with the number of angle mutations. According to this embodiment, the multi-turn signal anomaly of the pitch system encoder is diagnosed and analyzed based on the operating characteristics of the pitch system, effectively solving the problem of inaccurate diagnostic results caused by the traditional diagnostic method due to the uncertainty of the single-turn signal change amplitude, the uncertainty of the change frequency, the uncertainty of the pause time, etc., and improving the detection accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solution of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0023] Figure 1 It is a schematic diagram of blade angle value variation curves of three blades in a wind turbine generator set provided in an embodiment of the present application;

[0024] Figure 2 It is a schematic diagram of a blade angle value variation curve of a faulty shaft blade provided in an embodiment of the present application;

[0025] Figure 3 It is a flowchart of a pitch system encoder fault handling method provided in an embodiment of the present application;

[0026] Figure 4 is a schematic diagram of a blade angle value variation curve of a target blade provided in an embodiment of the present application;

[0027] Figure 5 is a schematic diagram of a blade angle value change curve when a target blade undergoes a sudden angle change provided in an embodiment of the present application;

[0028] Figure 6 It is a flowchart of a method for handling a pitch system encoder fault in an application scenario provided by an embodiment of the present application;

[0029] Figure 7 It is a structural schematic diagram of a pitch system encoder fault handling device provided in an embodiment of the present application;

[0030] Figure 8 It is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0031] The features and exemplary embodiments of various aspects of the present application will be described in detail below. In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain the present application, rather than to limit the present application. For those skilled in the art, the present application can be implemented without the need for some of these specific details. The following description of the embodiments is only to provide a better understanding of the present application by illustrating the examples of the present application.

[0032] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "include..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0033] For ease of understanding, the terms involved in the embodiments of the present application are first explained:

[0034] Feathering refers to the control process of turning the blades of a wind turbine to a state nearly parallel to the direction of the wind (also known as the safe position, which refers to the blade's position of about 89 degrees) after a wind turbine fails.

[0035] Pitch Angle: In a wind turbine, if the plane where the three blades are located is taken as a reference plane, then the angle between any blade and the reference plane is the blade pitch angle. The pitch angle on a wind turbine refers to the angle between the chord line of the airfoil at the top of the blade and the rotating plane.

[0036] Encoder, usually refers to photoelectric encoder, is a device that uses the principle of grating diffraction to realize the conversion of mechanical geometric displacement to digital signal, and compiles and converts digital signal into a signal form that can be used for communication, transmission and storage. It has been used in machine tools and computing instruments since the 1950s. Due to its simple structure, high measurement accuracy and long life, it has been widely used in precision positioning, speed, length, angle and other aspects.

[0037] A multi-turn encoder is a device used to measure the rotation angle. It can measure the rotation angle with high precision and high speed, and output the data to the motion control system, so as to accurately position and control the motion of robots, CNC machine tools and other equipment.

[0038] The multi-turn signal is a pulse signal corresponding to the multi-turn data in the multi-turn encoder.

[0039] The single-turn signal is a pulse signal used in a multi-turn encoder to match the single-turn data.

[0040] Before describing the technical solutions provided by the embodiments of the present application, in order to facilitate the understanding of the embodiments of the present application, the present application first specifically describes the problems existing in the prior art:

[0041] The multi-turn encoder used in the pitch control system may cause multi-turn signal abnormality due to various problems during use. When the multi-turn signal abnormality occurs, as the single-turn value detected by the multi-turn encoder increases, the multi-turn value no longer changes, which makes the blade angle value calculated based on the output signal of the multi-turn encoder no longer accurate. Figure 1 , is a schematic diagram of the blade angle value change curve of the three blades in a wind turbine generator set, where the horizontal axis is the time value and the vertical axis is the blade angle value. Take the wind turbine generator set at time 0 for example. Figure 1As shown, when the time is less than 0, the blade angle value change curves of the three blades are basically overlapped, and the encoders of the three blades are operating normally. After the time is greater than 0, the blade angle value change curves of two blades are still overlapped, and the blade angle values ​​continue to increase, so these two blades can be retracted normally, while the blade angle value of the other blade (hereinafter referred to as the faulty shaft blade for easy distinction) in the change curve only fluctuates slightly, and the overall trend presents a horizontal straight line. The reason for this phenomenon is that the multi-turn signal of the encoder corresponding to the faulty shaft blade is abnormal, causing the actual position of the faulty shaft blade to change, that is, it is in the retracted state, but the pitch controller in the pitch system no longer changes based on the blade angle value of the faulty shaft blade collected by the encoder. For further information, see Figure 2 ,for Figure 1 Schematic diagram of the blade angle value change curve of the faulty shaft blade after time 0, that is, the blade angle change curve after the encoder corresponding to the faulty shaft blade has multiple turns of abnormal signals. The change characteristic is that the blade angle value has continuous fluctuations or jumps, but the total value always remains within a fixed interval or range. Figure 2 The waveform shown, although it seems regular, Figure 2 It can be clearly seen that the amplitude of each jump, the frequency before and after, the value and number of short-time pauses are different. Combined with the operating principle of the variable pitch system, the main reasons are analyzed as follows:

[0042] The first reason: different PLC collection cycles result in different collected data points. That is, although the pulse type of a single turn of the encoder is 4196 or 8912, due to the scanning cycle of the PLC (such as 10ms or 20ms), the value collected at each collection point is random, and not every time the maximum or minimum value can be collected.

[0043] The second reason: Since the encoder rotates synchronously with the pitch motor, the encoder speed is different for different pitch adjustment or pitch retraction speeds, resulting in different frequencies. As shown in the figure, the frequency changes before and after. For different models and different pitch retraction speeds, other frequencies may appear. Therefore, it is difficult to accurately identify multi-turn signal anomalies due to the detection frequency, because the parameter value setting is very sensitive.

[0044] The third reason: Figure 1 As shown, there is a short pause in the value between 12 and 20 seconds, which will also have a significant impact on the data statistics.

[0045] The fourth reason: different encoder types, different machine models, and different total transmission ratios can also lead to different amplitudes or frequencies.

[0046] The fifth reason: the method of detecting frequency or amplitude changes can also be easily confused with normal pitch changes, leading to false detection. In some cases, the fluctuation of angle may also be caused by the fluctuation of given speed.

[0047] Therefore, it is difficult to accurately detect or identify the cause of the encoder fault by detecting it from the perspective of data statistics alone, that is, it is impossible to accurately identify whether a multi-turn signal abnormality has occurred.

[0048] Based on the above analysis and reasons, in order to accurately identify the multi-turn signal abnormality of the encoder, the embodiments of the present application provide a novel variable pitch system encoder fault handling method, device, electronic device and storage medium.

[0049] The following first describes a pitch system encoder fault handling method provided in an embodiment of the present application.

[0050] See also Figure 3 , is a flow chart of a pitch system encoder fault handling method provided in an embodiment of the present application, and the execution subject of the method may be a pitch controller in the pitch system. Figure 3 As shown, the method may include the following steps S31-S34.

[0051] S31. Determine the number of rotations of the target pitch motor corresponding to the target blade in the pitch system within a preset time period.

[0052] In some embodiments of the present application, the target blade refers to a blade in a wind turbine generator set that requires encoder fault processing.

[0053] The variable pitch system of a wind turbine generator set mainly includes a variable pitch controller and three servo control systems. The three servo control systems respectively control the blade angle value of each blade in the wind turbine generator set. The servo control system includes a variable pitch motor and a corresponding encoder, etc. In the embodiment of the present application, after determining the target blade, the variable pitch motor corresponding to the target blade in the variable pitch system is used as the target variable pitch motor, and the encoder corresponding to the target blade is used as the target encoder.

[0054] In an embodiment of the present application, the number of rotations of the target pitch motor refers to the number of rotations of the output shaft of the target pitch motor. In actual applications, the output shaft of the target pitch motor drives the target blade to rotate, thereby adjusting the target blade angle value. Therefore, there is a corresponding relationship between the number of rotations of the target pitch motor and the angle change value of the target blade. Based on this, the number of rotations of the target pitch motor within the preset time length can be determined according to the angle change value of the target blade within the preset time length.

[0055] The preset duration can be set according to actual conditions, for example, 1 second, 2 seconds, 5 seconds, etc. However, in order to improve the reliability of the wind turbine generator set, the preset duration should not be set too long, and in order to eliminate the single jump of the target encoder, the preset duration should not be set too short.

[0056] S32. Based on the output signal of the target encoder corresponding to the target blade in the pitch control system within the preset time length, determine the number of angle mutations of the target blade within the preset time length.

[0057] The number of sudden angle changes of the target blade within a preset time period refers to the number of sudden angle changes of the target blade within a preset time period.

[0058] In some embodiments of the present application, multiple sampling moments can be set within a preset duration. For each sampling moment, the angle value of the target blade at the sampling moment is calculated based on the signal output by the target encoder at the sampling moment. For any two adjacent sampling moments, if the difference between the two angle values ​​of the target blade calculated at the two adjacent sampling moments is greater than a preset difference threshold, it is determined that the target blade has a mutation. The number of angle mutations determined within the preset duration is accumulated to obtain the number of angle mutations of the target blade within the preset duration. The difference threshold can be set according to actual conditions, for example, it can be 0.15 degrees.

[0059] Usually, when the target blade has a sudden change in angle within a preset time, it can be determined that the target blade has a fault, and the fault may be caused by the abnormal multi-turn signal of the target encoder. Therefore, in order to further determine whether the fault is really caused by the abnormal multi-turn signal of the target encoder, S33 is further executed at this time. If the target blade does not have a sudden change in angle within the preset time, it can be considered that the target encoder does not have a multi-turn signal abnormality, because the multi-turn signal abnormality usually causes a sudden change in the target blade angle. At this time, the subsequent steps S33-S34 may no longer be executed.

[0060] S33. Compare the number of rotations with the number of angle mutations.

[0061] After obtaining the number of rotations and the number of angle mutations, the number of rotations and the number of angle mutations are compared to determine the size relationship between the two, and then determine whether the number of rotations and the number of angle mutations are consistent based on the size relationship.

[0062] In some embodiments of the present application, when comparing the number of rotations with the number of angle mutations, it can be determined whether the number of rotations is less than the number of angle mutations. If the number of rotations is less than the number of angle mutations, it is determined that the number of rotations is inconsistent with the number of angle mutations. If the number of rotations is not less than the number of angle mutations, that is, the number of rotations is greater than or equal to the number of angle mutations, the difference between the number of rotations and the number of angle mutations can be further calculated. If the difference is less than 1, it is determined that the number of rotations is consistent with the number of angle mutations. If the difference is greater than or equal to 1, it is determined that the number of rotations is inconsistent with the number of angle mutations. The reason why the number of rotations is determined to be consistent with the number of angle mutations when the difference between the number of rotations and the number of angle mutations is less than 1 is because the number of rotations may be a floating point number, that is, the number of rotations is not an integer. Since the value of less than one rotation can be calculated, and the number of angle mutations can only be detected when a mutation occurs, that is, the number of angle mutations is an integer, even if a fault is caused by an abnormal multi-turn signal, the number of rotations may not be equal to the number of angle mutations. Therefore, in order to ensure the accuracy of the detection, when the number of rotations is greater than the number of angle mutations and the difference between the two is less than 1, it is also determined that the number of rotations is consistent with the number of angle mutations.

[0063] S34. In response to the number of rotations being consistent with the number of angle mutations, it is determined that a target encoder corresponding to the target blade in the pitch control system has a multi-turn signal anomaly.

[0064] In some embodiments of the present application, the target encoder is a multi-turn photoelectric encoder, which is mainly composed of a grating disk and a photoelectric detection device, wherein the grating disk is coaxially arranged with the target pitch motor, and the rotation of the target pitch motor drives the rotation of the grating disk, and then a plurality of pulse signals are output through the photoelectric detection device, so that the rotation speed of the target pitch motor can be calculated according to the number of pulses per second of the pulse signal. The counting principle of the multi-turn photoelectric encoder is: after the grating disk rotates a single turn to the maximum value, the multi-turn count value is increased by 1. For example, for a 12×12 multi-turn photoelectric encoder, it means that there are 2 to the power of 12, a total of 4096 pulses per turn, that is, the maximum value of a single turn is 4096 turns. When the single turn reaches 4096 turns, the multi-turn count value is increased by 1, and the single-turn count value returns to 0. In the pitch system, the multi-turn count value of the multi-turn encoder is usually consistent with the number of turns of the pitch motor. Based on this, after a multi-turn signal failure occurs in the target encoder, the multi-turn count value no longer increases, but the single-turn signal value still maintains the change rule of returning to 0 every time it reaches the maximum value, which will cause the angle value of the target blade determined based on the target encoder to mutate each time it returns to 0. Based on this, if no other abnormalities occur in the target blade within the preset time length, the number of angle mutations within the preset time length is equivalent to the multi-turn count value of the target encoder within the preset time length under normal conditions, that is, it is consistent with the number of rotations of the target variable pitch motor within the preset time length. Therefore, when determining that the target blade has an angle mutation within the preset time length, by comparing the number of angle mutations of the target blade within the preset time length with the number of rotations of the target variable pitch motor, it can be determined whether the fault of the target blade is caused by the multi-turn signal abnormality of the target encoder. If the number of angle mutations is consistent with the number of rotations, it means that the fault is caused by the multi-turn signal abnormality, that is, it is determined that the target encoder has a multi-turn signal abnormality. Otherwise, it is determined to be caused by other abnormalities.

[0065] The pitch system encoder fault handling method provided in the embodiment of the present application determines the number of rotations of the target pitch motor corresponding to the target blade in the pitch system within a preset time length, determines the number of angle mutations of the target blade within the preset time length based on the output signal of the target encoder corresponding to the target blade in the pitch system within the preset time length, compares the number of rotations with the number of angle mutations, and determines that the target encoder has a multi-turn signal anomaly in response to the number of rotations being consistent with the number of angle mutations. According to this embodiment, the multi-turn signal anomaly of the pitch system encoder is diagnosed and analyzed based on the operating characteristics of the pitch system, which effectively solves the problem of inaccurate diagnostic results caused by the traditional diagnostic method due to the uncertainty of the single-turn signal change amplitude, the uncertainty of the change frequency, the uncertainty of the pause time, etc., and improves the detection accuracy.

[0066] In addition, the pitch system encoder fault handling method provided by the embodiment of the present application can promptly diagnose the real cause of the fault, reduce the troubleshooting time, and indirectly reduce the power generation loss caused by maintenance.

[0067] Furthermore, the traditional fault detection method based on statistical analysis has different pulse numbers for different types of encoders, which results in different blade angle variation ranges, making it difficult for parameter thresholds to adapt to all encoder types, and different retracting speeds will also have a significant impact on the data waveform. The variable pitch system encoder fault handling method provided in the embodiment of the present application is not limited by the encoder type, and is applicable to any type of encoder, making it more applicable.

[0068] Furthermore, the pitch system encoder fault handling method provided in the embodiment of the present application is not limited by the PLC scanning cycle and the data acquisition cycle, and therefore has wider versatility and applicability.

[0069] In some possible real-time methods of the present application, determining the number of rotations of a target pitch motor corresponding to a target blade in a pitch system within a preset time period may include:

[0070] Determine the rotational speed of the target blade;

[0071] Determine a first angle value that the target blade rotates through within a preset time period based on the rotation speed;

[0072] Determining a second angle value that the pitch motor rotates through within a preset time period according to the first angle value and the target total transmission ratio, wherein the target total transmission ratio is a total transmission ratio between the target blade and the target pitch motor;

[0073] The number of revolutions of the target variable pitch motor within a preset time period is determined according to the ratio of the second angle value to one revolution.

[0074] Here, a circle angle refers to the angle formed by a ray rotating around its endpoint, that is, 360 degrees.

[0075] In some embodiments of the present application, if the ratio of the second angle value to one circle angle is an integer, the ratio can be determined as the number of rotations of the target pitch motor within the preset time length. If the ratio of the second angle value to one circle angle is a floating point number, that is, a value with a decimal, the value obtained by rounding down the ratio can be determined as the number of rotations of the target pitch motor within the preset time length. For example, if the ratio is 12.8, the integer value 12 is taken as the number of rotations of the target pitch motor within the preset time length. The purpose of doing this is to ensure that when the failure of the target blade is caused by an abnormal multi-turn signal of the target encoder, the number of rotations of the target pitch motor within the preset time length can be equal to the number of angle mutations of the target blade.

[0076] In some embodiments of the present application, if the ratio of the second angle value to one circle angle is a floating point number, the ratio can also be directly determined as the number of rotations of the target variable pitch motor within a preset time length, but accordingly, in S33, when the number of rotations is greater than the number of angle mutations and the difference between the two is less than 1, it is also determined that the number of rotations is consistent with the number of angle mutations.

[0077] In some embodiments of the present application, the number of rotations of the target variable pitch motor within a preset time period may be calculated according to the following formula:

[0078]

[0079] Wherein, b represents the number of rotations of the target pitch motor within the preset time, v represents the speed of the target blade, T represents the preset time, n represents the total transmission ratio between the target blade and the target pitch motor, and 360° represents one rotation angle. Indicates rounding down.

[0080] In some embodiments of the present application, the target blade speed is 2 degrees / second, the target total transmission ratio is 2200, and the preset duration is 1 second. For example, the angle of the target variable pitch motor in 1 second is 2*2200=4400 degrees, corresponding to 4400 / 360=12.2 turns, rounded down to 12 turns. Figure 4 , which is a schematic diagram of the blade angle value change curve of the target blade, takes the blade angle value of the target blade from 1 second to 2 seconds as an example to determine the number of angle mutations of the target blade within 1 second. Figure 4 As shown, from 1 second to 2 seconds, the angle value suddenly changes 12 times, that is, the number of rotations of the target pitch motor within the preset time length is consistent with the number of angle mutations of the target blade within the preset time length. Therefore, it can be determined that there is a multi-turn signal anomaly in the target encoder.

[0081] Through the above method, the number of rotations of the target variable pitch motor within a preset time period can be quickly calculated.

[0082] In some possible implementations of the present application, the rotation speed of the target blade may be determined by at least one of the following methods:

[0083] The first method is to obtain the blade angle value of the target blade, determine the actual retracting speed of the target blade according to the blade angle value, and use the actual retracting speed as the rotational speed of the target blade.

[0084] The blade angle values ​​of the target blade can be collected multiple times within a certain period of time, and the blade angle change curve can be determined based on the blade angle values ​​collected multiple times, and then the actual retraction speed of the target blade can be determined based on the blade angle change curve.

[0085] The second method is to obtain the given speeds of all blades in the target wind turbine generator set, and take the average value of the given speeds of all blades as the rotation speed of the target blade. The target wind turbine generator set is the wind turbine generator set to which the target blade belongs.

[0086] The control method of the variable pitch system of a wind turbine generator set includes the variable pitch system receiving a speed instruction, i.e., a given speed, issued by a main controller of the wind turbine generator set, performing a variable pitch operation, and realizing a pitch adjustment function. Here, the value of the speed instruction issued by the main controller is calculated based on the actual position of the blade and the target position of the blade. The embodiment of the present application does not impose any limitation on this, so its detailed description is omitted.

[0087] Among them, the reason why the average value of the given speeds of the three blades is chosen as the speed of the target blade is that when a multi-turn signal abnormality occurs on a certain axis, the collected angle value is always at a small value, so the main controller will adjust the given speed.

[0088] The third method is to obtain the feathering speed output by the pitch controller in the pitch system, and use the feathering speed as the rotation speed of the target blade.

[0089] The feathering speed is a constant value.

[0090] In practical applications, one of the above three methods can be selected to determine the target blade rotation speed according to the operating state of the target wind turbine generator set.

[0091] For example, when the target wind turbine generator set is in a pitch-changing state, the first method or the second method may be used to determine the rotation speed of the target blades. When the target wind turbine generator set is in a fault state, the third method may be used to determine the rotation speed of the target blades.

[0092] For the third method, since the pitch system will have a constant feathering speed after triggering the three-blade angle inconsistency fault, the feathering speed is used as the target blade rotation speed after the fault is triggered. This can ensure that the pitch system encoder fault handling in the embodiment of the present application is fixed and will not be affected by changes in the given numerical value.

[0093] In some possible implementations of the present application, determining the number of angle mutations of the target blade within a preset time length based on an output signal of a target encoder corresponding to the target blade in the pitch system within a preset time length may include:

[0094] Within a preset time length, sampling the blade angle value of the target blade once every sampling period based on the output signal of the target encoder;

[0095] For each sampling, in response to the difference between the blade angle value obtained by the current sampling and the blade angle value obtained by the previous sampling being greater than the difference threshold, it is determined that a sudden change in angle occurs in the target blade;

[0096] The total number of angle mutations occurring within a preset time period is determined as the number of angle mutations of the target blade within the preset time period.

[0097] The length of the sampling period can be set according to actual conditions, for example, it can be 0.5 seconds, 1 second, etc.

[0098] In some embodiments of the present application, before determining the number of angle mutations of the target blade within a preset time, the user can clear the mutation count calculation value c in the pitch control system, and set a sampling start time, a preset time and a sampling period in the pitch controller according to actual conditions. In this way, when determining the number of angle mutations of the target blade within the preset time, the pitch controller can calculate the blade angle value of the target blade based on the output signal of the target encoder once every sampling period starting from the sampling start time, and for each calculated blade angle value, calculate the difference between the blade angle value and the blade angle value calculated last time, compare the difference with the difference threshold, and add 1 to the mutation count calculation value c when the difference is greater than the difference threshold, until the total sampling time reaches the preset time, and the obtained mutation count calculation value c is determined as the number of angle mutations of the target blade within the preset time. The sampling period can be a PLC scanning period set in the pitch system.

[0099] In some embodiments of the present application, see Figure 5 , is a schematic diagram of the blade angle value change curve when the target blade has a sudden change in angle, as shown in Figure 5 As shown, when the blade angle value changes suddenly before and after the cycle, the time interval between T1 and T2 is 3.33-3.42=0.02 seconds, that is, 20ms, which is exactly the scanning cycle of PLC. This proves the feasibility and correctness of the method of determining the number of sudden changes of the target blade angle in the embodiment of the present application.

[0100] With the above method, the user only needs to set a sampling start time, sampling period and preset duration to automatically determine the number of angle mutations of the target blade within the preset duration, which is simple to operate and highly efficient. It is not limited to the intermediate change process of the angle, the change range of the angle value, or the size of a given speed.

[0101] In some possible implementations of the present application, in response to the number of rotations being consistent with the number of angle mutations, determining that a target encoder corresponding to a target blade in a pitch control system has a multi-turn signal anomaly may further include:

[0102] In response to the number of rotations being consistent with the number of angle mutations, determining an angle change amplitude of the target blade within a preset time period;

[0103] Comparing the angle change amplitude with a preset angle change threshold;

[0104] In response to the angle change amplitude being less than the angle change threshold, it is determined that a target encoder corresponding to the target blade in the pitch control system has a multi-turn signal abnormality.

[0105] The angle change threshold can be set to a larger value, such as 2 degrees or 5 degrees, as long as it is greater than the change angle of the single-turn signal of the target encoder. The reason for this setting is that when the angle change amplitude is too large, it may be caused by other abnormalities.

[0106] Through the above method, the accuracy of the detection result of multi-turn signal abnormality can be further guaranteed.

[0107] In some possible implementations of the present application, based on the output signal of the target encoder corresponding to the target blade in the pitch control system within the preset time length, before determining the number of angle mutations of the target blade within the preset time length, the following steps may be performed first:

[0108] Determine whether the capacitance, voltage and temperature rise of the target pitch motor are within their respective corresponding preset normal ranges;

[0109] Based on the output signal of the target encoder corresponding to the target blade in the pitch system within the preset time length, determining the number of angle mutations of the target blade within the preset time length includes:

[0110] In response to the capacitance, voltage and temperature rise of the target pitch motor being within their respective corresponding preset normal ranges, the number of sudden angle changes of the target blade within a preset time period is determined.

[0111] The normal ranges corresponding to the capacitance, voltage and temperature rise of the target pitch motor can be set according to actual conditions, for example, according to the capacitance, voltage and temperature rise of the pitch system during normal operation.

[0112] Generally, the multi-turn signal abnormality of the target encoder does not cause the capacitance, voltage and temperature rise of the target pitch motor to be abnormal, that is, to exceed the corresponding normal range, while the capacitance, voltage and temperature rise of the target pitch motor may be abnormal due to blade jamming, abnormal incremental signal and other reasons. Therefore, if the capacitance, voltage and / or temperature rise of the target pitch motor are abnormal, it can basically be ruled out that the failure of the pitch system is caused by the multi-turn signal abnormality. At this time, in order to reduce the amount of calculation, S32 and subsequent steps can be no longer executed.

[0113] By using the above method, the amount of calculation can be reduced.

[0114] In some possible implementations of the present application, after determining that a target encoder corresponding to a target blade in a pitch control system has a multi-turn signal abnormality, the following steps may be performed:

[0115] Output abnormal alarm information, which is used to prompt the target encoder to have multi-turn signal abnormality.

[0116] By outputting alarm information, operation and maintenance personnel can detect abnormalities in time and perform repairs, thereby effectively reducing the greater adverse effects caused by multi-circle signal abnormalities.

[0117] In some possible implementations of the present application, the variable pitch system can continue to operate after outputting the alarm information. Based on this, before outputting the alarm information, it can be further determined whether the variable pitch system has a propeller jamming fault, such as a driver fault. When it is determined that there is no propeller jamming fault, the alarm information is output.

[0118] When the target encoder has multiple-turn signal anomalies, the position signal of the target blade detected by the driver in the pitch system will be wrong, which will cause the target pitch motor to operate abnormally, the motor current to increase, and even cause the driver to trigger an internal fault and shut down. After the driver of the pitch system fails, the pitch system will experience a stuck pitch phenomenon. At this time, the target pitch motor can no longer drive the target blade to a safe position, which poses a major hidden danger to the safety of the wind turbine. Therefore, when there is a stuck pitch fault in the pitch system, it is possible to output a stuck pitch fault prompt instead of an alarm message, or directly shut down the system to improve the safety of the wind turbine.

[0119] In some embodiments of the present application, it is possible to determine whether the pitch system still has a stuck propeller fault by detecting the fault word of the pitch system. For example, if the fault word is 0, it is determined that there is no stuck propeller fault, and an alarm message is output.

[0120] In some possible implementations of the present application, if only the target blade in the target wind turbine has a multi-turn signal abnormality and the other blades operate normally, it may cause the angle values ​​of the three blades in the target wind turbine to be inconsistent, triggering an "angle inconsistency" fault, and the angle inconsistency fault may cause a large deviation in the force of wind energy exerted on the three blades, that is, the impeller force is unbalanced, which will have a great impact on the load of the target wind turbine and reduce the service life of the target wind turbine. In view of this, in order to improve the safety of the target wind turbine, after determining that the target encoder corresponding to the target blade in the pitch system has a multi-turn signal abnormality, the following steps can also be performed:

[0121] Determine the first moment when a blade angle inconsistency fault occurs in a target wind turbine generator set, the target wind turbine generator set being the wind turbine generator set to which the target blade belongs;

[0122] Obtain a first blade angle value of a target blade at a first moment;

[0123] Determine the cumulative number of angle mutations of the target blade from the first moment to the second moment, the second moment being greater than the first moment;

[0124] The product of the accumulated number of angle mutations and one circle angle is determined as a third angle value rotated by the target pitch motor from the first moment to the second moment;

[0125] The ratio of the third angle value to the target total transmission ratio is determined as a fourth angle value rotated by the target blade from the first moment to the second moment, and the target total transmission ratio is the total transmission ratio between the target blade and the target pitch motor;

[0126] The sum of the first blade angle value and the fourth angle value is determined as the predicted blade angle value of the target blade at the second moment.

[0127] In some embodiments of the present application, an angle inconsistency fault of a target wind turbine generator set can be detected based on the angle difference between three blades in the target wind turbine generator set. For example, when the angle difference between the three blades in the target wind turbine generator set is greater than a preset angle, it can be determined that the target wind turbine generator set triggers an angle inconsistency fault, wherein the preset angle can be set in advance according to actual conditions, for example, it can be 2.5 degrees.

[0128] When determining that the target wind turbine generator set has a trigger angle inconsistency fault, record the angle value of the target blade at the first moment of the trigger angle inconsistency fault as the first blade angle value, and accumulate the number of times d when the target blade angle changes suddenly from the first moment until the second moment. The second moment can be obtained by adding the first moment to the fault tolerance time, where the fault tolerance time can be set according to the actual situation, but should not be too long. For example, the value range of the fault tolerance time can be 30 seconds to 2 minutes.

[0129] Based on the accumulated number of angle mutations d, the angle value s that the target pitch motor rotates from the first moment to the second moment can be calculated according to the following formula:

[0130] s=d*360° / n

[0131] Wherein, n represents the total transmission ratio between the target blade and the target pitch motor.

[0132] Exemplarily, if the cumulative number of target blade angle mutations from the first moment to the second moment is d = 200 times, the corresponding target pitch motor has rotated 200 times. If the target total transmission ratio is 2200, the angle value of the target blade from the first moment to the second moment is 200*360 / 2200 = 32.72 degrees. If the angle value of the target blade is 9 degrees when an angle inconsistency fault occurs, the actual angle value of the target blade at the second moment, that is, the predicted blade angle value, is 9+32.72 = 41.72 degrees.

[0133] Through the above method, after a multi-turn signal abnormality occurs in the target encoder, the pitch control system can continue to operate based on the predicted blade angle value of the target blade within the fault tolerance time, thereby achieving short-term fault-tolerant operation of the pitch control system during normal pitch adjustment.

[0134] In some possible implementations of the present application, after determining the sum of the first blade angle value and the fourth angle value as the predicted blade angle value of the target blade at the second moment, the following steps may also be performed:

[0135] Determine whether the target blade has completed retraction according to the predicted blade angle value;

[0136] In response to the target blade completing retraction, determining whether other blades have completed retraction;

[0137] In response to the other blades completing the retraction, the driver of the target pitch motor is controlled to stop outputting.

[0138] In some embodiments of the present application, when determining whether the target blade has completed the retraction based on the predicted blade angle value, the predicted blade angle value can be compared with a preset retraction stop angle. If the predicted blade angle value is greater than the retraction stop angle, it can be determined that the target blade has completed the retraction. If the blade angle value is not greater than the retraction stop angle, it can be determined that the target blade has not completed the retraction. The retraction stop angle can be set in advance according to actual conditions, usually to a value close to 90 degrees, such as 88 degrees.

[0139] In some embodiments of the present application, taking the retracted parking angle of 88 degrees as an example, after obtaining the predicted blade angle of the target blade at the second moment, the pitch controller determines whether the predicted blade angle is greater than 88 degrees. If the predicted blade angle is greater than 88 degrees, it is determined that the target blade has completed retracting; if the predicted blade angle is not greater than 88 degrees, it is determined that the target blade has not completed retracting.

[0140] In other embodiments of the present application, in order to improve the accuracy of control, when determining whether the target blade has completed retracting the propellers based on the predicted blade angle value, the predicted blade angle value can be first compared with the preset retracting stop angle. If the blade angle value is not greater than the retracting stop angle, it can be determined that the target blade has not completed retracting the propellers. If the predicted blade angle value is greater than the retracting stop angle, it is further determined whether the proximity switch corresponding to the target blade is triggered. If the proximity switch is triggered, it can be determined that the target blade has completed retracting the propellers. If the proximity switch is not triggered, it is determined that the target blade has not completed retracting the propellers. Compared to judging whether the target blade has completed retracting the propellers based on the predicted blade angle value, the judgment result based on the triggering state of the proximity switch is more accurate, which can ensure the accuracy of control.

[0141] For each of the other blades, when judging whether the blade has completed retraction, the blade angle value of the blade can be obtained. Similar to the method of determining whether the target blade has completed retraction, for each blade, whether the blade has completed retraction can be determined by comparing the blade angle value of the blade with the retraction stop angle. It can also be determined based on the blade angle value of the blade and the proximity switch corresponding to the blade. The specific determination process can refer to the above-mentioned determination process corresponding to the target blade. To avoid repetition, it will not be repeated here.

[0142] When it is determined that all three blades in the target wind turbine have completed retraction, the pitch controller can control the driver output of the target pitch motor to a given speed of 0, so that the driver stops running and the target pitch motor stops rotating, thereby preventing the limit from being triggered and preventing the toothed belt from being broken and mechanical parts from being damaged due to exceeding the limit.

[0143] In some possible implementations of the present application, the driver for controlling the target variable pitch motor based on the predicted blade angle value is mainly applicable to the scenario where a single-axis fault occurs in the target wind turbine generator set, that is, it is applicable to the scenario where only the target encoder has a multi-turn signal abnormality. Based on this, before determining whether other blades have completed retracting, it is possible to first determine whether the encoders corresponding to other blades have a multi-turn signal abnormality. If the encoders corresponding to other blades do not have a multi-turn signal abnormality, then determine whether other blades have completed retracting. Among them, the method of detecting whether the encoders corresponding to other blades have a multi-turn signal abnormality is consistent with the method of detecting whether the target encoder has a multi-turn signal abnormality. To avoid repetition, it will not be repeated here.

[0144] Through the above method, the accuracy of control can be further guaranteed.

[0145] The pitch system encoder fault handling method provided in an embodiment of the present application is described below by taking the application of the pitch system encoder fault handling method provided in an embodiment of the present application to a wind turbine generator set for performing fault handling on a target blade thereof as an example.

[0146] See also Figure 6 , the pitch system encoder fault handling method may include the following steps:

[0147] S61. The angle mutation count value c is reset, and the pitch controller collects the angle values ​​of the three blades and gives a given speed value.

[0148] S62. Determine whether the capacitance, voltage and motor temperature rise of the target pitch motor corresponding to the target blade are normal. If so, execute S63; if not, end.

[0149] This step is to determine whether the pitch control system is stuck or the incremental signal is abnormal, to ensure the accuracy of the detection.

[0150] S63. Determine whether the target blade has a sudden change in angle. If yes, execute S64; if no, execute S65.

[0151] This step is to determine the change in the angle value. If the difference in the angle values ​​of the target blade collected by the previous and next cycles, that is, the two adjacent collection points, is greater than the difference threshold, it is considered that a sudden angle change has occurred.

[0152] S64. The angle mutation count value c is increased by 1.

[0153] If the detected angle mutation is greater than 0.15 degrees, the count value is increased by 1; the total number of jumps within a fixed time is detected.

[0154] S65. Determine whether the preset time length T is reached. If so, execute S66; if not, return to execute S63.

[0155] The time of T can be set freely, such as 1 second, 2 seconds, 5 seconds, etc. However, in order to realize the following propeller safety protection control method, the setting of T should not be too long. In order to eliminate the single jump situation, the setting of T should not be too short.

[0156] S66. Determine whether the angle mutation count value c is greater than 0. If so, execute S67. If not, end.

[0157] S67. Calculate the number of revolutions b of the target pitch motor corresponding to the target blade within time T according to the given speed value and the total transmission ratio n.

[0158] The calculation formula for this step is as follows:

[0159]

[0160] Wherein, b represents the number of rotations of the target pitch motor within the preset time, v represents the given speed, T represents the preset time, n represents the total transmission ratio between the target blade and the target pitch motor, 360° represents one rotation angle, Indicates rounding down.

[0161] S68. Determine whether the condition that c=b is satisfied and the angle change amplitude within T seconds is less than the threshold value. If so, execute S69; if not, end.

[0162] This step mainly includes two tests:

[0163] Check whether the values ​​of c and b are consistent.

[0164] Check whether the angle change is greater than a certain value, for example, and whether the angle change is less than a threshold. This step is to further ensure the correctness of the detection. The threshold setting can be set to a larger value, such as 2 degrees or 5 degrees, as long as it is greater than the change angle of the encoder single-turn signal.

[0165] S69. Output the alarm information that there is multi-turn signal abnormality in the target encoder.

[0166] If the detected c value is equal to the b value within the T time and there is no other abnormality in the variable pitch system, an alarm message of abnormal encoder multi-turn signal is output.

[0167] S610. Determine the predicted blade angle value of the target blade according to the alarm information, the angle value of the target blade when the pitch system triggers an angle inconsistency fault, and the cumulative number of angle mutations of the target blade within the fault tolerance time.

[0168] This step means that if a multi-turn signal abnormality is detected in the target encoder, the pitch controller determines the predicted blade angle value of the target blade based on the angle value of the target blade when the "angle inconsistency" fault is triggered and the accumulated number of angle mutations of the target blade within the fault tolerance time.

[0169] Exemplarily, when the difference in the angle values ​​of the three blades in a single wind turbine unit is greater than 2.5 degrees, an angle inconsistency fault is determined to be triggered, and the angle value of the target blade is recorded at this time.

[0170] The cumulative number of angle mutations within the fault tolerance time is set to d, and the angle value of the target pitch motor within the fault tolerance time can be calculated according to the following formula:

[0171] s=d*360° / n

[0172] Wherein, n represents the total transmission ratio between the target blade and the target pitch motor.

[0173] The predicted blade angle of the target blade is obtained by adding the angle value of the target pitch motor rotated and the angle value of the target blade recorded when the fault occurs and the trigger angle is inconsistent.

[0174] This calculation method can also be used for short-term fault-tolerant operation during normal pitch adjustment, but the fault-tolerant time should not be too long. The start condition is based on the angle mutation, and the starting angle is the angle before the angle mutation, not the angle when the fault occurs.

[0175] S611. Determine whether the predicted blade angle value is greater than 88 and the proximity switch corresponding to the target blade is triggered. If so, execute S612; if not, end.

[0176] S612. Determine whether the remaining blades except the target blade meet the following conditions: the blade angle values ​​of all blades are greater than 88 degrees, the proximity switches corresponding to all blades are triggered, and the encoders corresponding to all blades do not have an alarm message of abnormal multi-turn signals. If so, execute S613; if not, end.

[0177] S613. Stop the driver output corresponding to the target pitch motor, and stop retracting the target blades.

[0178] This step is the propeller safety protection involved in the embodiment of the present application, that is, when it is detected that the actual position of the blade has reached the safe position, the pitch controller controls the driver output, that is, sets the given speed to 0, stops the driver from running and the pitch motor from rotating, prevents the limit from being triggered, and prevents the toothed belt from being broken and the mechanical parts from being damaged due to exceeding the limit.

[0179] Based on the pitch system encoder fault processing method provided in the above embodiment, the present application also provides a specific implementation of the pitch system encoder fault processing device. Please refer to the following embodiment.

[0180] See also Figure 7 The pitch system encoder fault processing device provided in the embodiment of the present application includes the following modules:

[0181] The first determination module 701 is used to determine the number of rotations of the target pitch motor corresponding to the target blade in the pitch system within a preset time period;

[0182] A second determination module 702 is used to determine the number of angle mutations of the target blade within a preset time length based on an output signal of a target encoder corresponding to the target blade in the pitch control system within a preset time length;

[0183] A comparison module 703, used for comparing the number of rotations with the number of angle mutations;

[0184] The abnormality determination module 704 is used to determine that a target encoder corresponding to a target blade in the pitch control system has a multi-turn signal abnormality in response to the number of rotations being consistent with the number of angle mutations.

[0185] The present application discloses a pitch system encoder fault handling device, which determines the number of rotations of the target pitch motor corresponding to the target blade in the pitch system within a preset time length, determines the number of angle mutations of the target blade within the preset time length based on the output signal of the target encoder corresponding to the target blade in the pitch system within the preset time length, compares the number of rotations with the number of angle mutations, and determines that the target encoder has a multi-turn signal anomaly in response to the number of rotations being consistent with the number of angle mutations. According to this embodiment, the multi-turn signal anomaly of the pitch system encoder is diagnosed and analyzed based on the operating characteristics of the pitch system, which effectively solves the problem of inaccurate diagnostic results caused by the uncertainty of the single-turn signal change amplitude, the uncertainty of the change frequency, the uncertainty of the pause time, etc. in the traditional diagnostic method, and improves the detection accuracy.

[0186] In some possible implementations of the present application, the first determining module 701 includes:

[0187] A rotation speed determination submodule, used to determine the rotation speed of the target blade;

[0188] A first angle determination submodule, used to determine a first angle value rotated by the target blade within a preset time period based on the rotation speed;

[0189] A second angle determination submodule is used to determine a second angle value that the pitch motor rotates through within a preset time length according to the first angle value and a target total transmission ratio, where the target total transmission ratio is a total transmission ratio between a target blade and a target pitch motor;

[0190] The revolution number determination submodule is used to determine the number of revolutions of the target variable pitch motor within a preset time period according to the ratio of the second angle value to one revolution.

[0191] In some possible implementations of the present application, the speed determination submodule is specifically used to:

[0192] Obtaining a blade angle value of a target blade, determining an actual blade retraction speed of the target blade according to the blade angle value, and using the actual blade retraction speed as the rotation speed of the target blade; or,

[0193] Obtaining the given speeds of all blades in the target wind turbine generator set, and taking the average of the given speeds of all blades as the rotation speed of the target blade, the target wind turbine generator set being the wind turbine generator set to which the target blade belongs; or,

[0194] The feathering speed output by the pitch controller in the pitch system is obtained, and the feathering speed is used as the rotation speed of the target blade.

[0195] In some possible implementations of the present application, the second determining module 702 is specifically configured to:

[0196] Within a preset time length, sampling the blade angle value of the target blade once every sampling period based on the output signal of the target encoder;

[0197] For each sampling, in response to the difference between the blade angle value obtained by the current sampling and the blade angle value obtained by the previous sampling being greater than the difference threshold, it is determined that a sudden change in angle occurs in the target blade;

[0198] The total number of angle mutations occurring within a preset time period is determined as the number of angle mutations of the target blade within the preset time period.

[0199] In some possible implementations of the present application, the abnormality determination module 704 is specifically configured to:

[0200] In response to the number of rotations being consistent with the number of angle mutations, determining an angle change amplitude of the target blade within a preset time period;

[0201] Comparing the angle change amplitude with a preset angle change threshold;

[0202] In response to the angle change amplitude being less than the angle change threshold, it is determined that a target encoder corresponding to the target blade in the pitch control system has a multi-turn signal abnormality.

[0203] In some possible implementations of the present application, the apparatus may further include:

[0204] An abnormality module is used to determine whether the capacitance, voltage and temperature rise of the target pitch motor are within their respective corresponding preset normal ranges before determining the number of angle mutations of the target blade within a preset time length;

[0205] The second determining module 702 is specifically configured to:

[0206] In response to the capacitance, voltage and temperature rise of the target pitch motor being within their respective corresponding preset normal ranges, the number of angle mutations of the target blade within the preset time length is determined based on the output signal of the target encoder corresponding to the target blade in the pitch system within the preset time length.

[0207] In some possible implementations of the present application, the device further includes:

[0208] a blade angle prediction module, for determining the first moment when a blade angle inconsistency fault occurs in a target wind turbine generator set after determining that a target encoder corresponding to a target blade in a pitch control system has a multi-turn signal anomaly, the target wind turbine generator set being the wind turbine generator set to which the target blade belongs;

[0209] Obtain a first blade angle value of a target blade at a first moment;

[0210] Determine the cumulative number of angle mutations of the target blade from the first moment to the second moment, the second moment being greater than the first moment;

[0211] The product of the accumulated number of angle mutations and one circle angle is determined as a third angle value rotated by the target pitch motor from the first moment to the second moment;

[0212] The ratio of the third angle value to the target total transmission ratio is determined as a fourth angle value rotated by the target blade from the first moment to the second moment, and the target total transmission ratio is the total transmission ratio between the target blade and the target pitch motor;

[0213] The sum of the first blade angle value and the fourth angle value is determined as the predicted blade angle value of the target blade at the second moment.

[0214] In some possible implementations of the present application, the device further includes: a control module, configured to:

[0215] After determining the sum of the first blade angle value and the fourth angle value as the predicted blade angle value of the target blade at the second moment, determining whether the target blade has completed retraction and whether the retraction angle is greater than a preset retraction stop angle according to the predicted blade angle value;

[0216] In response to the target blade completing retraction, determining whether other blades have completed retraction;

[0217] In response to the other blades completing the retraction, the driver of the target pitch motor is controlled to stop outputting.

[0218] The pitch system encoder fault processing device provided in the embodiment of the present application can achieve Figures 3 to 6 To avoid repetition, the various processes implemented by the method embodiment are not described here.

[0219] Figure 8 A schematic diagram of the hardware structure of an electronic device provided in an embodiment of the present application is shown.

[0220] The electronic device may include a processor 801 and a memory 802 storing computer program instructions.

[0221] Specifically, the processor 801 may include a central processing unit (CPU), or an application specific integrated circuit (ASIC), or may be configured to implement one or more integrated circuits of the embodiments of the present application.

[0222] The memory 802 may include a large capacity memory for data or instructions. By way of example and not limitation, the memory 802 may include a hard disk drive (HDD), a floppy disk drive, a flash memory, an optical disk, a magneto-optical disk, a tape, or a universal serial bus (USB) drive, or a combination of two or more of these. Where appropriate, the memory 802 may include a removable or non-removable (or fixed) medium. Where appropriate, the memory 802 may be inside or outside the integrated gateway disaster recovery device. In a specific embodiment, the memory 802 is a non-volatile solid-state memory. The memory 802 may include a read-only memory (ROM), a random access memory (RAM), a disk storage medium device, an optical storage medium device, a flash memory device, an electrical, optical, or other physical / tangible memory storage device. Therefore, typically, the memory 802 includes one or more tangible (non-transitory) computer-readable storage media (e.g., a memory device) encoded with software including computer executable instructions, and when the software is executed (e.g., by one or more processors), it may perform the operations described in any one of the pitch system encoder fault handling methods in the above-mentioned embodiments.

[0223] The processor 801 implements any one of the pitch system encoder fault processing methods in the above embodiments by reading and executing computer program instructions stored in the memory 802 .

[0224] In one example, the electronic device may further include a communication interface 803 and a bus 810. Figure 8 As shown, the processor 801, the memory 802, and the communication interface 803 are connected via a bus 810 and communicate with each other.

[0225] The communication interface 803 is mainly used to implement communication between various modules, devices, units and / or equipment in the embodiments of the present application.

[0226] Bus 810 includes hardware, software or both, and the parts of online data flow billing equipment are coupled to each other. For example, but not limitation, bus may include accelerated graphics port (AGP) or other graphics bus, enhanced industrial standard architecture (EISA) bus, front-end bus (FSB), hypertransport (HT) interconnection, industrial standard architecture (ISA) bus, infinite bandwidth interconnection, low pin count (LPC) bus, memory bus, micro channel architecture (MCA) bus, peripheral component interconnection (PCI) bus, PCI-Express (PCI-X) bus, serial advanced technology attachment (SATA) bus, video electronics standard association local (VLB) bus or other suitable bus or two or more of these combinations. In appropriate cases, bus 810 may include one or more buses. Although the present application embodiment describes and shows a specific bus, the application considers any suitable bus or interconnection.

[0227] In addition, in combination with the pitch system encoder fault handling method in the above embodiment, the embodiment of the present application can provide a computer storage medium for implementation. The computer storage medium stores computer program instructions; when the computer program instructions are executed by the processor, any pitch system encoder fault handling method in the above embodiment is implemented.

[0228] It should be clear that the present application is not limited to the specific configuration and processing described above and shown in the figures. For the sake of simplicity, a detailed description of the known method is omitted here. In the above embodiments, several specific steps are described and shown as examples. However, the method process of the present application is not limited to the specific steps described and shown, and those skilled in the art can make various changes, modifications and additions, or change the order between the steps after understanding the spirit of the present application.

[0229] The functional blocks shown in the above-described block diagram can be implemented as hardware, software, firmware or a combination thereof. When implemented in hardware, it can be, for example, an electronic circuit, an application specific integrated circuit (ASIC), appropriate firmware, a plug-in, a function card, etc. When implemented in software, the elements of the present application are programs or code segments that are used to perform the required tasks. The program or code segment can be stored in a machine-readable medium, or transmitted on a transmission medium or a communication link by a data signal carried in a carrier wave. "Machine-readable medium" can include any medium capable of storing or transmitting information. Examples of machine-readable media include electronic circuits, semiconductor memory devices, ROM, flash memory, erasable ROM (EROM), floppy disks, CD-ROMs, optical disks, hard disks, optical fiber media, radio frequency (RF) links, etc. The code segment can be downloaded via a computer network such as the Internet, an intranet, etc.

[0230] It should also be noted that the exemplary embodiments mentioned in this application describe some methods or systems based on a series of steps or devices. However, this application is not limited to the order of the above steps, that is, the steps can be performed in the order mentioned in the embodiment, or in a different order from the embodiment, or several steps can be performed simultaneously.

[0231] Aspects of the present disclosure are described above with reference to the flowchart and / or block diagram of the method, device (system) and computer program product according to the embodiment of the present disclosure. It should be understood that each box in the flowchart and / or block diagram and the combination of each box in the flowchart and / or block diagram can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device to produce a machine so that these instructions executed by the processor of the computer or other programmable data processing device enable the implementation of the function / action specified in one or more boxes of the flowchart and / or block diagram. Such a processor can be, but is not limited to, a general-purpose processor, a special-purpose processor, a special application processor, or a field programmable logic circuit. It can also be understood that each box in the block diagram and / or flowchart and the combination of boxes in the block diagram and / or flowchart can also be implemented by dedicated hardware that performs a specified function or action, or can be implemented by a combination of dedicated hardware and computer instructions.

[0232] The above is only a specific implementation of the present application. Those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working processes of the systems, modules and units described above can refer to the corresponding processes in the aforementioned method embodiments, and will not be repeated here. It should be understood that the protection scope of the present application is not limited to this. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed in this application, and these modifications or replacements should be included in the protection scope of this application.

Claims

1. A method for handling faults of a pitch system encoder, characterized in that: include: Determine the number of rotations of a target pitch motor corresponding to a target blade in the pitch system within a preset time period; Determine the number of angle mutations of the target blade within the preset time length based on an output signal of a target encoder corresponding to the target blade in the pitch system within the preset time length; Comparing the number of rotations with the number of angle mutations; In response to the number of rotations being consistent with the number of angle mutations, it is determined that a multi-turn signal anomaly exists in the target encoder.

2. The method according to claim 1, characterized in that The step of determining the number of rotations of a target pitch motor corresponding to a target blade in the pitch system within a preset time period includes: determining a rotational speed of the target blade; Determine a first angle value rotated by the target blade within the preset time period based on the rotation speed; Determining a second angle value rotated by the pitch motor within the preset time period according to the first angle value and a target total transmission ratio, wherein the target total transmission ratio is a total transmission ratio between the target blade and the target pitch motor; The number of rotations of the target pitch motor within a preset time period is determined according to the ratio of the second angle value to one circle angle.

3. The method according to claim 2, characterized in that The determining of the rotation speed of the target blade adopts at least one of the following methods: Acquire a blade angle value of the target blade, determine an actual blade retraction speed of the target blade according to the blade angle value, and use the actual blade retraction speed as a rotation speed of the target blade; Obtaining given speeds of all blades in a target wind turbine generator set, and taking an average value of the given speeds of all blades as the rotation speed of the target blade, the target wind turbine generator set being the wind turbine generator set to which the target blade belongs; A feathering speed output by a pitch controller in the pitch system is obtained, and the feathering speed is used as the rotation speed of the target blade.

4. The method according to claim 1, characterized in that The determining, based on an output signal of a target encoder corresponding to the target blade in the pitch system within the preset time period, the number of sudden angle changes of the target blade within the preset time period comprises: Within the preset time length, sampling the blade angle value of the target blade once every sampling period based on the output signal of the target encoder; For each sampling, in response to the difference between the blade angle value obtained by the current sampling and the blade angle value obtained by the previous sampling being greater than the difference threshold, it is determined that the target blade has a sudden change in angle; The total number of angle mutations occurring within the preset time period is determined as the number of angle mutations of the target blade within the preset time period.

5. The method according to claim 1, characterized in that In response to the number of rotations being consistent with the number of angle mutations, determining that a target encoder corresponding to the target blade in the pitch control system has a multi-turn signal anomaly includes: In response to the number of rotations being consistent with the number of angle mutations, determining an angle change amplitude of the target blade within the preset time period; Comparing the angle change amplitude with a preset angle change threshold; In response to the angle change amplitude being less than the angle change threshold, it is determined that a target encoder corresponding to the target blade in the pitch control system has a multi-turn signal abnormality.

6. The method according to any one of claims 1 to 5, characterized in that: Before determining the number of angle mutations of the target blade within the preset time period based on the output signal of the target encoder corresponding to the target blade in the pitch system within the preset time period, the method further includes: Determining whether the capacitance, voltage and temperature rise of the target pitch motor are within respective corresponding preset normal ranges; The determining, based on an output signal of a target encoder corresponding to the target blade in the pitch system within the preset time period, the number of sudden angle changes of the target blade within the preset time period comprises: In response to the capacitance, voltage and temperature rise of the target pitch motor being within their respective corresponding preset normal ranges, the number of angle mutations of the target blade within the preset time length is determined based on the output signal of the target encoder corresponding to the target blade in the pitch system within the preset time length.

7. The method according to any one of claims 1 to 5, characterized in that: After determining that a target encoder corresponding to the target blade in the pitch control system has a multi-turn signal abnormality, the method further includes: Determine a first moment when a blade angle inconsistency fault occurs in a target wind turbine generator set, wherein the target wind turbine generator set is a wind turbine generator set to which the target blade belongs; Acquire a first blade angle value of the target blade at the first moment; Determine the cumulative number of angle mutations of the target blade from the first moment to a second moment, the second moment being greater than the first moment; The product of the accumulated number of angle mutations and one circle angle is determined as a third angle value rotated by the target pitch motor from the first moment to the second moment; Determine the ratio of the third angle value to the target total transmission ratio as a fourth angle value rotated by the target blade from the first moment to the second moment, the target total transmission ratio being the total transmission ratio between the target blade and the target pitch motor; The sum of the first blade angle value and the fourth angle value is determined as the predicted blade angle value of the target blade at the second moment.

8. The method according to claim 7, characterized in that After determining the sum of the first blade angle value and the fourth angle value as the predicted blade angle value of the target blade at the second moment, the method further includes: Determine, based on the predicted blade angle value, whether the target blade has completed retraction and whether the retraction angle is greater than a preset retraction stop angle; In response to the target blade completing retraction, determining whether other blades have completed retraction; In response to the other blades completing the retraction, the driver of the target pitch motor is controlled to stop outputting.

9. A pitch system encoder fault processing device, characterized in that: include: A first determination module is used to determine the number of rotations of a target pitch motor corresponding to a target blade in the pitch system within a preset time period; A second determination module is used to determine the number of angle mutations of the target blade within the preset time length based on an output signal of a target encoder corresponding to the target blade in the pitch system within the preset time length; A comparison module, used for comparing the number of rotations with the number of angle mutations; The abnormality determination module is used to determine that a target encoder corresponding to the target blade in the variable pitch system has a multi-turn signal abnormality in response to the number of rotations being consistent with the number of angle mutations.

10. An electronic device, characterized in that: The electronic device comprises: a processor and a memory storing computer program instructions; When the processor executes the computer program instructions, the pitch system encoder fault processing method according to any one of claims 1 to 8 is implemented.

11. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer program instructions, and when the computer program instructions are executed by the processor, the pitch system encoder fault handling method according to any one of claims 1 to 8 is implemented.

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