Automatic blade position calibration method and calibration device, electronic equipment and storage medium

Abstract

The invention discloses an automatic blade position calibration method and device, electronic equipment and a storage medium. The method comprises the steps that after a paddle moves to the position of a limiting switch, the paddle is controlled to move in the preset rotating direction, and the triggering angle and the leaving angle of each proximity switch are obtained based on the fact that an induction check block sequentially passes through the proximity switches; the paddle is controlled to operate in the reverse direction, and the trigger angle and the departure angle of each proximity switch are obtained based on the fact that the induction check block sequentially passes through the proximity switches; for each proximity switch, obtaining each error of the proximity switch based on each pre-learned trigger angle and each pre-learned departure angle; when the absolute value of each error does not exceed the respective corresponding interval, calculating the average value of each error of all proximity switches; calculating a difference value between the physical position angle of the limit switch and the average value; and calibrating the current position angle of the paddle as the difference value. According to the method provided by the embodiment of the invention, the blade position can be automatically calibrated, the labor cost is saved, and the fault can be quickly eliminated.

Description

Technical Field

[0001] This application relates to the field of wind power generation technology, specifically to an automatic blade position calibration method, calibration device, electronic equipment, and storage medium. Background Technology

[0002] A pitch control system is installed in the wind turbine hub. This system consists of three drives controlling three motors, which in turn connect to the blades, thus controlling the blade angles. The blade angle is detected by a rotary transformer in the motor. If the rotary transformer malfunctions, the blades will retract to the limit switch position, indicating that the angle calculated by the rotary transformer is no longer accurate. Therefore, after clearing the fault, a drive zero-degree calibration is required. Conventional maintenance involves manually climbing into the hub, manually extending the blades to the 0-degree position, performing the blade zero-degree calibration, and then re-performing the proximity switch self-learning. For offshore wind turbines, due to weather, maritime regulations, and other reasons, personnel may be unable to access the tower for maintenance, forcing the turbine to remain shut down and resulting in energy waste.

[0003] Therefore, there is an urgent need for an automatic calibration scheme that eliminates the need for manual tower calibration after a resolver failure.

[0004] The above statements are for the purpose of providing background information in relation to this application only and do not necessarily constitute prior art. Summary of the Invention

[0005] The purpose of this application is to provide an automatic blade position calibration method, calibration device, electronic device, and storage medium to solve the problem in related technologies where, when a rotary transformer fails and personnel cannot access the tower for repairs, the wind turbine must be shut down, resulting in energy waste. To provide a basic understanding of some aspects of the disclosed embodiments, a brief summary is given below. This summary is not intended as a general commentary, nor is it intended to identify key / important components or describe the scope of protection of these embodiments. Its sole purpose is to present some concepts in a simple form as a prelude to the detailed description that follows.

[0006] According to one aspect of the embodiments of this application, an automatic blade position calibration method is provided, the method comprising: After the blade reaches the limit switch position, the blade is controlled to run in a preset rotation direction. Based on the sensing block on the blade bearing, the blade passes through one or more proximity switches in the pitch system in sequence to obtain the first trigger angle and the first departure angle of each proximity switch. The propeller is controlled to run in the opposite direction of the preset rotation direction. Based on the induction block passing through each of the proximity switches in sequence, the second trigger angle and the second departure angle of each proximity switch are obtained. For each proximity switch, based on the pre-learned third trigger angle, third departure angle, fourth trigger angle, and fourth departure angle, a first error, a second error, a third error, and a fourth error corresponding to the proximity switch are obtained; the first error is the difference between the first trigger angle and the third trigger angle; the second error is the difference between the first departure angle and the third departure angle; the third error is the difference between the second trigger angle and the fourth trigger angle; and the fourth error is the difference between the second departure angle and the fourth departure angle. If the absolute values ​​of the first error, the second error, the third error, and the fourth error do not exceed their respective preset ranges, calculate the average value of the first error, the second error, the third error, and the fourth error of all the proximity switches. Calculate the difference between the physical position angle of the limit switch and the average value; The current position angle of the blade is calibrated to the difference between the physical position angle of the limit switch and the average value.

[0007] In some embodiments of this application, the third trigger angle and the third departure angle are the trigger angle and departure angle when the sensing block passes the proximity switch during the pre-learning process, when the propeller is running in the preset rotation direction; the fourth trigger angle and the fourth departure angle are the trigger angle and departure angle when the sensing block passes the proximity switch during the pre-learning process, when the propeller is running in the opposite direction of the preset rotation direction.

[0008] In some embodiments of this application, the preset range is 0-4°.

[0009] In some embodiments of this application, after the step of calibrating the current position angle of the propeller blade to the difference between the physical position angle of the limit switch and the average value, the method further includes: The propeller is controlled to run in a preset rotation direction. Based on the induction block passing through each of the proximity switches in sequence, the fifth trigger angle and the fifth departure angle of each proximity switch are obtained. The propeller is controlled to run in the opposite direction of the preset rotation direction. Based on the sequential passing of the sensing block through each of the proximity switches, the sixth trigger angle and the sixth departure angle of each proximity switch are obtained. For each proximity switch, a first deviation, a second deviation, a third deviation, and a fourth deviation are obtained; the first deviation is the difference between the fifth trigger angle and the third trigger angle; the second deviation is the difference between the fifth departure angle and the third departure angle; the third deviation is the difference between the sixth trigger angle and the fourth trigger angle; and the fourth deviation is the difference between the sixth departure angle and the fourth departure angle. If the absolute values ​​of the first deviation, the second deviation, the third deviation, and the fourth deviation all do not exceed a preset threshold, the calibration is deemed successful; otherwise, the calibration is deemed unsuccessful.

[0010] In some embodiments of this application, the preset threshold is 0.1°.

[0011] In some embodiments of this application, if any one of the absolute values ​​of the first error, the second error, the third error, or the fourth error exceeds the preset range, the automatic calibration is exited, and the propeller is moved to the limit switch position.

[0012] In some embodiments of this application, the physical angular position of the limit switch is 91°.

[0013] According to another aspect of the embodiments of this application, an automatic blade position calibration device is provided, comprising: The first control module is used to control the blade to run in a preset rotation direction after the blade runs to the limit switch position, and to obtain the first trigger angle and the first departure angle of each proximity switch based on the induction block on the blade bearing passing through one or more proximity switches in the pitch system in sequence. The second control module is used to control the blade to run in the opposite direction of the preset rotation direction, and to obtain the second trigger angle and the second departure angle of each proximity switch based on the sequential passing of the sensing block through each proximity switch. The error acquisition module is used to acquire a first error, a second error, a third error, and a fourth error corresponding to the proximity switch based on the pre-learned third trigger angle, third departure angle, fourth trigger angle, and fourth departure angle; the first error is the difference between the first trigger angle and the third trigger angle; the second error is the difference between the first departure angle and the third departure angle; the third error is the difference between the second trigger angle and the fourth trigger angle; and the fourth error is the difference between the second departure angle and the fourth departure angle. The first calculation module is used to calculate the average value of the first error, the second error, the third error, and the fourth error of all the proximity switches, provided that the absolute values ​​of the first error, the second error, the third error, and the fourth error do not exceed their respective preset intervals. The second calculation module is used to calculate the difference between the physical position angle of the limit switch and the average value; A calibration module is used to calibrate the current position angle of the propeller blade to the difference between the physical position angle of the limit switch and the average value.

[0014] According to another aspect of the embodiments of this application, an electronic device is provided, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the automatic blade position calibration method of any embodiment of this application.

[0015] According to another aspect of the embodiments of this application, a computer-readable storage medium is provided having a computer program stored thereon, the computer program being executed by a processor to implement the automatic blade position calibration method of any embodiment of this application.

[0016] One aspect of the technical solution provided in this application embodiment may include the following beneficial effects: The automatic blade position calibration method provided in this application embodiment controls the blade to run in a preset rotation direction after it reaches the limit switch position. Based on the sensing block on the blade bearing sequentially passing through one or more proximity switches in the pitch system, the method acquires the first trigger angle and first departure angle of each proximity switch. Then, the method controls the blade to run in the opposite direction of the preset rotation direction. Based on the sensing block sequentially passing through each proximity switch, the method acquires the second trigger angle and second departure angle of each proximity switch. For each proximity switch, based on the pre-learned third trigger angle, third departure angle, fourth trigger angle, and fourth departure angle, the method acquires the corresponding first error and second error. The system calculates the first, second, third, and fourth errors. The first error is the difference between the first and third trigger angles; the second error is the difference between the first and third departure angles; the third error is the difference between the second and fourth trigger angles; and the fourth error is the difference between the second and fourth departure angles. Assuming that the absolute values ​​of the first, second, third, and fourth errors do not exceed their respective preset ranges, the average of the first, second, third, and fourth errors of all proximity switches is calculated. The difference between the physical position angle of the limit switch and the average value is then calculated, and the current position angle of the blade is calibrated to this difference. This scheme is an automatic calibration scheme that eliminates the need for manual tower calibration after a resolver fault. It utilizes pre-learned proximity switch angle values ​​to reverse-calibrate the resolver angle, thereby achieving automatic blade position calibration. This avoids manual intervention, saves labor and material costs, and can quickly eliminate faults, improving wind turbine power generation capacity.

[0017] The above description is merely an overview of the technical solutions of the embodiments of this application. In order to better understand the technical means of the embodiments of this application and to implement them in accordance with the contents of the specification, and to make the above and other objects, features and advantages of the embodiments of this application more obvious and understandable, specific implementation methods of this application are described below. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments or related technologies of this application, the drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 A flowchart of an automatic blade position calibration method according to an embodiment of this application is shown.

[0020] Figure 2 A schematic diagram of the arrangement of N proximity switches according to an embodiment of this application is shown.

[0021] Figure 3 A flowchart of an automatic blade position calibration method according to another embodiment of this application is shown.

[0022] Figure 4 A flowchart of an automatic blade position calibration method according to another embodiment of this application is shown.

[0023] Figure 5 A structural block diagram of an automatic blade position calibration device according to an embodiment of this application is shown.

[0024] Figure 6 A block diagram of an electronic device structure according to an embodiment of this application is shown.

[0025] Figure 7 A schematic diagram of a computer-readable storage medium according to an embodiment of this application is shown. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of this application clearer, the application will be further described below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application. All other embodiments obtained by those skilled in the art based on the embodiments in this application without inventive effort are within the scope of protection of this application.

[0027] It will be understood by those skilled in the art that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. It should also be understood that terms such as those defined in general dictionaries should be understood to have a meaning consistent with their meaning in the context of the prior art, and should not be interpreted in an idealized or overly formal sense unless specifically defined as herein.

[0028] The relevant technology incorporates a pitch control system installed in the hub of the wind turbine. This system consists of three drivers controlling three motors, which are connected to the blades to control their angle of attack. The blade angle is detected by a resolver in the motor, which is a non-absolute encoder. Each rotation of the resolver detects an angle from 0° to 360°. The motor connects to the blades via a reduction gearbox, typically with a reduction ratio of 1000 to 3000. For example, with a reduction ratio of 2000, a 360° rotation of the resolver corresponds to a blade rotation of 360° / 2000 = 0.18°. Because the resolver is a non-absolute encoder and there is a ratio between the resolver angle and the blade angle, the drivers need to detect the number of revolutions of the resolver. In practical applications, resolver failures are common in wind turbines, leading to inaccurate blade positions. When a resolver fails, the blades retract to the limit switch position (triggered by a high-level signal to the driver). It is determined that the angle calculated by the resolver at this point cannot be used as the true blade angle, necessitating a driver zero-level calibration. The drive calibration process is as follows: First, rotate the blade to mechanical 0 degrees (there is a scale at the root of the blade, and this scale is considered to be 0 degrees when it is aligned with the 0 mark on the hub), and then perform drive calibration (notify the drive that the angle calculated by the resolver is 0 degrees at this time).

[0029] For onshore wind turbines, maintenance personnel can promptly go up the tower to calibrate the drive when problems occur; however, for offshore wind turbines, due to inconvenient transportation, it is impossible to reach the turbine in a timely manner, and the turbine has to be shut down.

[0030] The relevant technologies lack a solution for automatically calibrating the blade position. When the rotary transformer fails and personnel cannot access the tower for repairs, the wind turbine must be shut down, resulting in energy waste. Furthermore, manual blade position calibration suffers from poor calibration results and low efficiency.

[0031] To address the problems existing in related technologies, this application provides an automatic blade position calibration method. After the blade reaches the limit switch position, the blade is controlled to run in a preset rotation direction. Based on the sensing block on the blade bearing, the blade sequentially passes through one or more proximity switches in the pitch system to obtain the first trigger angle and first departure angle of each proximity switch. The blade is then controlled to run in the opposite direction of the preset rotation direction. Based on the sensing block sequentially passing through each proximity switch, the second trigger angle and second departure angle of each proximity switch are obtained. For each proximity switch, based on the pre-learned third trigger angle, third departure angle, fourth trigger angle, and fourth departure angle, the corresponding first error, second error, third error, and fourth error are obtained. The first error is the difference between the first trigger angle and the third trigger angle, and the second error is the difference between the first departure angle and the third departure angle. The difference between the first and fourth departure angles is calculated, where the third error is the difference between the second and fourth trigger angles, and the fourth error is the difference between the second and fourth departure angles. Under the condition that the absolute values ​​of the first, second, third, and fourth errors do not exceed their respective preset ranges, the average of the first, second, third, and fourth errors of all proximity switches is calculated. The difference between the physical position angle of the limit switch and the average value is calculated, and the current position angle of the blade is calibrated to this difference. This scheme is an automatic calibration scheme that eliminates the need for manual tower calibration after a resolver fault occurs. It utilizes the pre-learned proximity switch angle values ​​to reverse-calibrate the resolver angle, thereby achieving automatic blade position calibration, avoiding manual intervention, saving labor and material costs, and quickly eliminating faults, thus improving wind turbine power generation capacity.

[0032] The following description, in conjunction with the accompanying drawings, describes an automatic blade position calibration method, an automatic blade position calibration device, an electronic device, and a computer-readable storage medium according to embodiments of this application.

[0033] refer to Figure 1 As shown, one embodiment of this application provides an automatic blade position calibration method, which can be applied to a pitch system. The number of proximity switches in the pitch system can be one or more. The method may include steps S10-S60: S10. After the blade moves to the limit switch position, control the blade to run in a preset rotation direction. Based on the sensing block on the blade bearing, pass through one or more proximity switches in the pitch system in sequence to obtain the first trigger angle and the first departure angle of each proximity switch.

[0034] For example, the physical position of the limit switch includes, but is not limited to, 91°. This example uses a limit switch with a physical position of 91° as an example, refer to... Figure 2 As shown, Figure 2A schematic diagram of the arrangement of N proximity switches is shown, where N≥1. The proximity switches numbered 1, 2, 3, ..., N are arranged sequentially along a circle from the 0° position to the 91° position. Specifically, the propeller blades can be controlled to start at a preset speed (the blade angle changes from the 90° position to the 0° position). During the start-up process, based on the sensing blocks on the blade bearings, the propeller blades sequentially pass through one or more proximity switches in the pitch control system to obtain the first trigger angle and the first departure angle of each proximity switch.

[0035] In a specific example, the number of proximity switches in the pitch system is N=1. After the propeller blade retracts to the 91° limit switch position due to a resolver malfunction, it enters automatic calibration mode upon receiving an automatic calibration command from the main controller. The propeller blade deploys at a preset speed Speed_Learn. When the digital signal from the driver detects that the 91° limit switch has just left the position, the operation stops. At this point, the propeller blade is considered to be at the critical position triggered by the 91° limit switch. Because the propeller blade angle calculated by the resolver is a random value at this time, the current angle is first calibrated to 91° (when the 91° limit switch is triggered, the actual blade angle will not be exactly 91°, but is generally within the range of 91°±2°; subsequent solutions aim to clarify this deviation). The propeller blade deploys at the preset speed Speed_Learn (the blade angle changes from the 90° position to the 0° position), causing the sensing block to pass through the proximity switch SB. The trigger angle PB5 and the departure angle PB6 are recorded. The trigger angle PB5 is the first trigger angle of the proximity switch SB; the departure angle PB6 is the first departure angle of the proximity switch SB.

[0036] In another specific example, the number of proximity switches in the pitch system is N > 1, allowing for reverse calibration of the resolver angle based on the proximity switch angle values. When the propeller blade retracts to the 91° limit switch position due to a resolver malfunction, it receives an automatic calibration command from the main controller and enters automatic calibration mode. The propeller blade is controlled to start at a preset speed (Speed_Learn). When the driver digital signal detects that the 91° limit switch has just left the position, operation stops; at this point, the propeller blade is considered to be at the critical position triggered by the 91° limit switch. Because the resolver-calculated propeller blade angle is random at this time, the current angle is first calibrated to 91° (when the 91° limit switch is triggered, the actual propeller blade angle will not be exactly 91°, but generally within the range of 91 ± 2°; subsequent solutions aim to clarify this deviation). The propeller blade starts at the preset speed (Speed_Learn) (i.e., the running direction from 90° to 0°), causing the sensing block to pass the Nth proximity switch, and the trigger angle P is recorded. 90-0-n C, departure angle P 90-0-n L.

[0037] S20. Control the blades to run in the opposite direction of the preset rotation direction. Based on the induction block passing through each proximity switch in sequence, obtain the second trigger angle and the second departure angle of each proximity switch.

[0038] For example, controlling the blades to run in the opposite direction of a preset rotation direction can control the blades to retract at a preset speed (the blades rotate from 0° to 90°). During the retraction process, based on the sensing blocks passing through each proximity switch in sequence, the second trigger angle and the second departure angle of each proximity switch are obtained.

[0039] For example, based on the physical position of the preset 91° limit switch, the preset rotation direction can be the rotation direction of the blade from 90° to 0°, and the opposite direction of the preset rotation direction is the rotation direction of the blade from 0° to 90°.

[0040] Specifically, in the example where the number of proximity switches in the pitch system is N=1, the propeller blades can be controlled to retract at a preset speed Speed_Learn (i.e., moving in a direction from 0° position to 90° position), causing the sensing block to pass through one proximity switch SB. The trigger angle PB7 and departure angle PB8 of the proximity switch SB are recorded. PB7 is the second trigger angle of the proximity switch, and PB8 is the second departure angle of the proximity switch.

[0041] Specifically, in an example where the number of proximity switches in the pitch system is N > 1, the propeller blades can be controlled to continue running from 90° to 0°, passing the (N-1), N-2, ..., 1st proximity switches, recording the trigger angle and departure angle. The propeller blades are then controlled to retract at a preset speed (Speed_Learn) (i.e., running from 0° to 90°), causing the sensing block to pass the first proximity switch, and the trigger angle P corresponding to the first proximity switch is recorded. 0-90-1 C, and the departure angle P corresponding to the first proximity switch. 0-90-1 L, i.e., P 0-90-1 C is the second trigger angle of the first proximity switch, P 0-90-1 L is the second departure angle of the first proximity switch.

[0042] S30. For each proximity switch, based on the pre-learned third trigger angle, third departure angle, fourth trigger angle, and fourth departure angle, obtain the first error, second error, third error, and fourth error corresponding to the proximity switch.

[0043] The first error is the difference between the first trigger angle and the third trigger angle; the second error is the difference between the first departure angle and the third departure angle; the third error is the difference between the second trigger angle and the fourth trigger angle; and the fourth error is the difference between the second departure angle and the fourth departure angle.

[0044] The third trigger angle and the third departure angle are the trigger angle and departure angle when the sensing block passes the proximity switch during the pre-learning process, when the blade is running in the preset rotation direction; the fourth trigger angle and the fourth departure angle are the trigger angle and departure angle when the sensing block passes the proximity switch during the pre-learning process, when the blade is running in the opposite direction of the preset rotation direction. These angles are learned during the pre-learning process under fault-free conditions of the pitch system.

[0045] For ease of description, in the example where the number of proximity switches N=1 in the pitch system, the previously learned proximity switch angles are defined as: the trigger angle PB1 and departure angle PB2 of proximity switch SB when the blade moves from 0° to 90°; and the trigger angle PB3 and departure angle PB4 of proximity switch SB when the blade moves from 90° to 0°. For ease of description, in the example where the number of proximity switches N>1 in the pitch system, the following definition is made: During normal commissioning, the angle learned by proximity switch n is: when moving from 0° to 90°, the trigger angle is P... right-0-90-n C, departure angle is P right-0-90-n L; When running from 90° to 0°, the trigger angle is P right-90-0-n C, departure angle is P right-90-0-n L.

[0046] In the example where the number of proximity switches in the pitch system is N=1, the third trigger angle is PB3, the third departure angle is PB4, the fourth trigger angle is PB1, and the fourth departure angle is PB2. The errors between the recognized angle and the angle learned by the original proximity switches are calculated as follows: ErrB1 = PB5 - PB3; ErrB2 = PB6 - PB4; ErrB3 = PB7 - PB1; ErrB4 = PB8 - PB2. In this example, the first error is ErrB1; the second error is ErrB2; the third error is ErrB3; and the fourth error is ErrB4.

[0047] For example, in a pitch system with a number of proximity switches N > 1, for a proximity switch numbered n (where 1 ≤ n ≤ N, and n is an integer), the first error Err n_1 The first trigger angle P of the proximity switch 90-0-n C and the pre-acquired third trigger angle P right-90-0-n The difference of C, i.e., Err n_1 =P 90-0-n CP right-90-0-n C; Second error Err n_2 The first departure angle P of the proximity switch 90-0-n L and the pre-acquired third departure angle P right-90-0-n The difference of L, i.e., Err n_2 =P 90-0-n LPright-90-0-n L; the third error is the second trigger angle P of the proximity switch. 0-90-n C and the pre-acquired fourth trigger angle P right-0-90-n The difference of C, i.e., Err n_3 =P 0-90-n CP right-0-90-n C; The fourth error is the second departure angle P of the proximity switch. 0-90-n L and the pre-acquired fourth departure angle P right-0-90-n The difference of L, i.e., Err n_4 =P 0-90-n LP right-0-90-n L; Third trigger angle P right-90-0-n C is the trigger angle pre-learned by the proximity switch when the blade is running in a preset rotation direction; the third departure angle P right-90-0-n L is the pre-learned departure angle of the proximity switch when the blade is running in a preset rotation direction; the fourth trigger angle P right-0-90-n C is the trigger angle pre-learned by the proximity switch when the blade is running in the opposite direction of the preset rotation direction; the fourth departure angle P right-0-90-n L represents the pre-learned departure angle of the proximity switch when the blade rotates in the opposite direction of the preset rotation direction. Based on the pre-acquired trigger angles and departure angles, the errors corresponding to the actual trigger angles and departure angles are obtained. Based on the corresponding errors, the final value of the blade after calibration is calculated, which can further improve the accuracy of the calculation results of the final value of the blade after calibration.

[0048] Pre-acquired third trigger angle P right-90-0-n C. The pre-acquired third departure angle P right-90-0-n L, the pre-acquired fourth trigger angle P right-0-90-n C and the pre-acquired fourth departure angle P right-0-90-n L can be obtained through pre-tuning and learning, that is, the angle learned by the proximity switch numbered n is: When the propeller blades rotate from 0° to 90°, the trigger angle of the proximity switch numbered n is P. right-0-90-n C, departure angle is P right-0-90-n L; When the propeller blades rotate from 90° to 0°, the trigger angle of the proximity switch numbered n is P. right-90-0-n C, departure angle is P right-90-0-n L.

[0049] In the example where the number of proximity switches in the pitch system is N > 1, for the proximity switch numbered n, the error between the recognized angle and the angle learned by the original proximity switch is calculated as follows: Err n_1 =P 90-0-n CPright-90-0-n C; Err n_2 =P 90-0-n LP right-90-0-n L; Err n_3 =P 0-90-n CP right-0-90-n C; Err n_4 =P 0-90-n LP right-0-90-n L.

[0050] S40. If the absolute values ​​of the first error, the second error, the third error, and the fourth error do not exceed their respective preset ranges, calculate the average value of the first error, the second error, the third error, and the fourth error of all proximity switches.

[0051] For example, for a proximity switch numbered n, where 1 ≤ n ≤ N, if |Err n_1 |≤First preset threshold, and|Err n_2 |≤ the second preset threshold, and |Err n_3 |≤Third preset threshold, and|Err n_4 If |≤ the fourth preset threshold, then calculate the average of the first error, second error, third error and fourth error of all proximity switches.

[0052] The first, second, third, and fourth preset thresholds can all be set between 0 and 4 degrees. The preset range can be 0-4 degrees.

[0053] The formula for calculating Errave, the average of the first, second, third, and fourth errors of all proximity switches, is Errave = (Err) 1_1 +Err 1_2 +Err 1_3 +Err 1_4 +…+Err n_1 +Err n_2 +Err n_3 +Err n_4 +…+Err N_1 +Err N_2 +Err N_3 +Err N_4 ) / (4*N). N is the total number of proximity switches in the pitch system.

[0054] In the example where the number of proximity switches in the pitch system is N=1, if |ErrB1|≤ the first preset threshold, and |ErrB2|≤ the second preset threshold, and |ErrB3|≤ the third preset threshold, and |ErrB4|≤ the fourth preset threshold, then the average value of the first error, second error, third error and fourth error of the proximity switch is calculated, and the calculation formula is Errave=(ErrB1+ErrB2+ ErrB3+ ErrB4) / 4.

[0055] In the example where the number of proximity switches in the pitch system is N > 1, for the proximity switch numbered n, if |Err n_1 |≤First preset error value, and|Err n_2 |≤Second preset error value, and|Err n_3 |≤Third preset error value, and|Err n_4 If |≤ the fourth preset error value, then calculate the average value Errave of the first error, second error, third error and fourth error of the proximity switch. The first preset error value, second preset error value, third preset error value and fourth preset error value can be set according to the actual application needs. For example, they can be taken from the range of 0° to 4°, or all of them can be 4°.

[0056] The final value of the calibrated blade is obtained by calculating the errors of each trigger angle and each departure angle, which can reduce the influence of each error and improve the accuracy of the final value of the calibrated blade.

[0057] S50. Calculate the difference between the physical position angle of the limit switch and the average value.

[0058] The physical position angle of the limit switch includes, but is not limited to, 91°. In one specific embodiment, the difference between 91° and the average value is calculated; this difference is the final value of the blade after calibration. That is, the final value of the blade after calibration is 91° - Errave. This can further improve the accuracy of the obtained final value.

[0059] In the example where the number of proximity switches in the pitch system is N=1, the physical position angle of the limit switch is 91°. The difference between the physical position angle of the limit switch and the average value is 91°-Errave.

[0060] In the example where the number of proximity switches N > 1 in the pitch system, the physical position angle of the limit switch is 91°. The difference between the physical position angle of the limit switch and the average value is 91° - Errave.

[0061] S60. Calibrate the current position angle of the blade to the difference between the physical position angle of the limit switch and the average value.

[0062] In the example where the number of proximity switches N=1, the current position angle of the blade is calibrated to the difference between the physical position angle of the limit switch and the average value: 91°-Errave.

[0063] In the example where the number of proximity switches N > 1, the current position angle of the blade is calibrated to the difference between the physical position angle of the limit switch and the average value: 91° - Errave.

[0064] The current position angle of the propeller blade is calibrated to the final value, thus completing one automatic calibration of the propeller blade position. The calibration result is accurate and the calibration efficiency is high. No manual operation is required, which reduces labor costs.

[0065] In related technologies, proximity switch learning is performed when the blade resolver is normal. However, in this embodiment, when a resolver fault occurs, the resolver angle is calibrated in reverse using the pre-learned proximity switch angle value, thereby achieving automatic blade position calibration. Therefore, compared with related technologies, the solution in this embodiment is a "reverse" calibration solution, which improves calibration accuracy and calibration efficiency.

[0066] refer to Figure 3 As shown, in some embodiments, after calibrating the current position angle of the blade to the difference between the physical position angle of the limit switch and the average value, the method may further include: S70, control the propeller blades to run in a preset rotation direction, and obtain the fifth trigger angle and fifth departure angle of each proximity switch based on the induction block passing through one or more proximity switches in the pitch system in sequence.

[0067] In the example where the number of proximity switches N=1, the propeller is controlled to learn the opening angle (i.e., the propeller moves in the direction of 90°→0°) at a preset speed Speed_Learn, so that the stop passes the proximity switch SB, and the trigger angle PB9 and departure angle PB10 of SB are recorded. In this example, the fifth trigger angle is PB9 and the fifth departure angle is PB10.

[0068] In the example where the number of proximity switches N > 1, the propeller is controlled to learn the opening angle at a preset speed Speed_Learn (the propeller moves in the direction of 90°→0°), so that the stop passes through N proximity switches in sequence, and the trigger angle of the proximity switch numbered n is recorded as P. check-90-0-n C, departure angle is P check-90-0-n L, 1≤n≤N. In this example, the fifth trigger angle of the proximity switch numbered n is P. check-90-0-n C, the fifth departure angle is P check-90-0-n L.

[0069] S80, control the propeller to run in the opposite direction of the preset rotation direction, and obtain the sixth trigger angle and sixth departure angle of each proximity switch based on the sequential passing of the sensing block through each proximity switch.

[0070] In the example where the number of proximity switches N=1, the control blades are controlled to learn the angle of retraction (i.e., the control blades are controlled to run in the direction of 0°→90°) according to the speed Speed_Learn, so that the stop passes the proximity switch SB, and the trigger angle PB11 and departure angle PB12 of SB are recorded; in this example, the sixth trigger angle is PB11 and the sixth departure angle is PB12.

[0071] In the example where the number of proximity switches N > 1, the propeller is controlled to learn the angle by retracting at a preset speed Speed_Learn (the propeller moves in the direction from 0° to 90°), causing the stop to pass through N proximity switches. The trigger angle of the proximity switch numbered n is recorded as P. check-0-90-n C, departure angle is P check-0-90-n L. In this example, the sixth trigger angle of the proximity switch numbered n is P. check-0-90-n C, the sixth departure angle is P check-0-90-n L.

[0072] S90. For each proximity switch, obtain the first deviation, second deviation, third deviation and fourth deviation corresponding to the proximity switch; the first deviation is the difference between the fifth trigger angle and the third trigger angle; the second deviation is the difference between the fifth departure angle and the third departure angle; the third deviation is the difference between the sixth trigger angle and the fourth trigger angle; the fourth deviation is the difference between the sixth departure angle and the fourth departure angle.

[0073] In the example where the number of proximity switches N=1, the first deviation is CheckErrB1, the second deviation is CheckErrB2, the third deviation is CheckErrB3, and the fourth deviation is CheckErrB4. The formulas for calculating each deviation are as follows: CheckErrB1=PB9-PB3; CheckErrB2=PB10-PB4; CheckErrB3=PB11-PB1; CheckErrB4=PB12-PB2; In this example, PB9 is the fifth trigger angle, PB10 is the fifth departure angle, PB11 is the sixth trigger angle, PB12 is the sixth departure angle, PB3 is the third trigger angle, PB4 is the third departure angle, PB1 is the fourth trigger angle, and PB2 is the fourth departure angle.

[0074] In the example where the number of proximity switches N > 1, for the proximity switch numbered n (1 ≤ n ≤ N), the first deviation is CheckErr. n_1The second deviation is CheckErr n_2 The third deviation is CheckErr n_3 The fourth deviation is CheckErr. n_4 The formulas for calculating each deviation are as follows: CheckErr n_1 =P check-90-0-n CP right-90-0-n C; CheckErr n_2 =P check-90-0-n LP right-90-0-n L; CheckErr n_3 =P check-0-90-n CP right-0-90-n C; CheckErr n_4 =P check-0-90-n LP right-0-90-n L.

[0075] Among them, P right-90-0-n C is the third trigger angle corresponding to proximity switch number n, P right-90-0-n L is its corresponding third departure angle, P right-0-90-n C is its corresponding fourth trigger angle, P right-0-90-n L is its corresponding fourth departure angle, P check-90-0-n C is its corresponding fifth trigger angle, P check-90-0-n L is its corresponding fifth departure angle, P check-0-90-n C is its corresponding sixth trigger angle, P check-0-90-n L is its corresponding sixth departure angle.

[0076] S100: If the absolute values ​​of the first deviation, the second deviation, the third deviation, and the fourth deviation do not exceed their respective preset thresholds, the calibration is deemed successful; otherwise, the calibration is deemed unsuccessful.

[0077] For example, the preset threshold can be set according to the needs of the actual application, such as 0.1°.

[0078] In the example where the number of proximity switches N=1, the preset threshold corresponding to |CheckErrB1| is the first error value, the preset threshold corresponding to |CheckErrB2| is the second error value, the preset threshold corresponding to |CheckErrB3| is the third error value, and the preset threshold corresponding to |CheckErrB4| is the fourth error value. The first, second, third, and fourth error values ​​are all preset according to actual application needs and can be the same or different; for example, they can all be set to 0.1°. If |CheckErrB1|≤ the first error value, and |CheckErrB2|≤ the second error value, and |CheckErrB3|≤ the third error value, and |CheckErrB4|≤ the fourth error value, then the calibration is considered successful; otherwise, the calibration is considered unsuccessful.

[0079] In the example where the number of proximity switches N=1, for the proximity switch numbered n, |CheckErr n_1 The corresponding preset threshold is the first error value. |CheckErr n_2 The corresponding preset threshold is the second error value, |CheckErr n_3 The corresponding preset threshold is the third error value. |CheckErr n_4 The corresponding preset threshold is the fourth error value; if |CheckErr n_1 |≤First Error Value、|CheckErr n_2 |≤Second Error Value、|CheckErr n_3 |≤Third error value, and|CheckErr n_4 If the error value is less than or equal to the fourth error value, the calibration is considered successful; otherwise, the calibration is considered unsuccessful. The first, second, third, and fourth error values ​​can be preset according to actual application needs, for example, they can all be set to 0.1°.

[0080] For example, if any one of the absolute values ​​of the first error, the second error, the third error, or the fourth error exceeds its corresponding preset threshold, the automatic calibration is exited and the blade is moved to the limit switch position.

[0081] By determining whether the calibration was successful, the calibration results can be automatically checked, which can reduce calibration errors.

[0082] refer to Figure 4 As shown, Figure 4 A flowchart illustrating an automatic blade position calibration method as a specific example of this application is shown.

[0083] The automatic blade position calibration method of this application, when a resolver failure necessitates recalibration of the resolver angle, utilizes a learned proximity switch to calibrate the resolver angle in reverse. This eliminates the need for manual tower access, enabling automatic remote calibration without human intervention, thus saving manpower and material costs. It can quickly eliminate faults and improve wind turbine power generation capacity. After calibration, the method automatically checks the calibration results to ensure their accuracy. This application's method solves the problem of recalibrating the resolver angle after a resolver failure, and the entire function is completed independently by the pitch control system, saving costs.

[0084] The description of the various embodiments above tends to emphasize the differences between the various embodiments. The similarities or similarities between them can be referred to, and for the sake of brevity, they will not be repeated here.

[0085] refer to Figure 5 As shown, another embodiment of this application provides an automatic blade position calibration device, comprising: The first control module is used to control the blade to run in a preset rotation direction after the blade runs to the limit switch position. Based on the sensing block on the blade bearing passing through one or more proximity switches in the pitch system in sequence, the module obtains the first trigger angle and the first departure angle of each proximity switch. The second control module is used to control the blade to run in the opposite direction of the preset rotation direction. Based on the induction block passing through each proximity switch in sequence, the second trigger angle and the second departure angle of each proximity switch are obtained. The error acquisition module is used to acquire the first error, second error, third error, and fourth error corresponding to the proximity switch based on the pre-learned third trigger angle, third departure angle, fourth trigger angle, and fourth departure angle; the first error is the difference between the first trigger angle and the third trigger angle; the second error is the difference between the first departure angle and the third departure angle; the third error is the difference between the second trigger angle and the fourth trigger angle; and the fourth error is the difference between the second departure angle and the fourth departure angle. The first calculation module is used to calculate the average value of the first error, the second error, the third error, and the fourth error of all proximity switches, provided that the absolute values ​​of the first error, the second error, the third error, and the fourth error do not exceed their respective preset ranges. The second calculation module is used to calculate the difference between the physical position angle of the limit switch and the average value; The calibration module is used to calibrate the current position angle of the propeller blades to the difference.

[0086] For example, the third trigger angle and the third departure angle are the trigger angle and departure angle when the sensing block passes the proximity switch during the pre-learning process, when the blade is running in the preset rotation direction; the fourth trigger angle and the fourth departure angle are the trigger angle and departure angle when the sensing block passes the proximity switch during the pre-learning process, when the blade is running in the opposite direction of the preset rotation direction.

[0087] For example, the preset range is 0-4°.

[0088] Exemplarily, the device further includes: The third control module is used to control the blades to run in a preset rotation direction. Based on the induction block passing through one or more proximity switches in the pitch system in sequence, it obtains the fifth trigger angle and the fifth departure angle of each proximity switch. The fourth control module is used to control the blade to run in the opposite direction of the preset rotation direction. Based on the induction block passing through each proximity switch in sequence, it obtains the sixth trigger angle and the sixth departure angle of each proximity switch. The deviation acquisition module is used to acquire the first deviation, second deviation, third deviation and fourth deviation corresponding to each proximity switch; the first deviation is the difference between the fifth trigger angle and the third trigger angle; the second deviation is the difference between the fifth departure angle and the third departure angle; the third deviation is the difference between the sixth trigger angle and the fourth trigger angle; and the fourth deviation is the difference between the sixth departure angle and the fourth departure angle. The judgment module is used to determine that the calibration is successful if the absolute values ​​of the first deviation, the second deviation, the third deviation, and the fourth deviation do not exceed the preset threshold; otherwise, the calibration is determined to have failed.

[0089] For example, the preset threshold is 0.1°.

[0090] For example, the device may further include a reset module, which is used to exit automatic calibration and run the blade to the limit switch position if any one of the absolute values ​​of the first error, the second error, the third error, or the fourth error exceeds a preset range.

[0091] For example, the physical angular position of the limit switch is 91°.

[0092] The automatic blade position calibration device provided in this application embodiment controls the blade to run in a preset rotation direction after the blade reaches the limit switch position. Based on the sensing block on the blade bearing sequentially passing through one or more proximity switches in the pitch system, the device obtains the first trigger angle and the first departure angle of each proximity switch. Then, the device controls the blade to run in the opposite direction of the preset rotation direction. Based on the sensing block sequentially passing through each proximity switch, the device obtains the second trigger angle and the second departure angle of each proximity switch. For each proximity switch, based on the pre-learned third trigger angle, third departure angle, fourth trigger angle, and fourth departure angle, the device obtains the corresponding first error, second error, third error, and fourth error. The first error is the difference between the first and third trigger angles, and the second error is the difference between the first and third departure angles. The difference between the first, second, third, and fourth errors is calculated. The third error is the difference between the second and fourth trigger angles, and the fourth error is the difference between the second and fourth departure angles. Under the condition that the absolute values ​​of the first, second, third, and fourth errors do not exceed their respective preset ranges, the average value of the first, second, third, and fourth errors of all proximity switches is calculated. The difference between the physical position angle of the limit switch and the average value is calculated, and the current position angle of the blade is calibrated to this difference. This scheme is an automatic calibration scheme that does not require manual tower calibration after a resolver failure. It fully considers the influence of the errors of the first trigger angle, first departure angle, second trigger angle, and second departure angle of the proximity switch, thereby enabling automatic blade position calibration with good calibration effect and high calibration efficiency.

[0093] The description of the various embodiments above tends to emphasize the differences between the various embodiments. The similarities or similarities between them can be referred to, and for the sake of brevity, they will not be repeated here.

[0094] Another embodiment of this application provides an electronic device including a memory, a processor, and a computer program stored in the memory and executable on the processor, the processor executing the computer program to implement the method of any of the above embodiments.

[0095] refer to Figure 6 As shown, the electronic device 10 may include: a processor 100 and a memory 101. The memory 101 stores a computer program that can run on the processor 100. When the processor 100 runs the computer program, it executes the automatic blade position calibration method provided in any of the foregoing embodiments of this application. The electronic device 10 includes, but is not limited to, a PLC controller, a pitch driver, etc.

[0096] The memory 101 may include high-speed random access memory (RAM), and may also include non-volatile memory, such as at least one disk storage device.

[0097] Processor 100 may be an integrated circuit chip with signal processing capabilities. In implementation, each step of the above method can be completed by the integrated logic circuitry in the hardware of processor 100 or by instructions in software form. The processor 100 may be a general-purpose processor, including a Central Processing Unit (CPU), a Network Processor (NP), etc.; it may also be a Digital Signal Processor (DSP), an Application-Specific Integrated Circuit (ASIC), an Off-the-shelf Programmable Gate Array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. It can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of this application. The general-purpose processor may be a microprocessor or any conventional processor. The steps of the methods disclosed in the embodiments of this application can be directly embodied in the execution of a hardware decoding processor, or executed by a combination of hardware and software modules in the decoding processor. The software modules may reside in random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, or other mature storage media in the art. The storage medium is located in memory 101. The processor 100 reads the information in memory 101 and, in conjunction with its hardware, completes the steps of the above method.

[0098] The electronic devices and methods provided in the embodiments of this application are based on the same inventive concept and have the same beneficial effects as the methods they employ, operate, or implement.

[0099] Another embodiment of this application provides a computer-readable storage medium having a computer program stored thereon, which is executed by a processor to implement the automatic blade position calibration method of any of the above embodiments. Reference Figure 7 As shown, the computer-readable storage medium is an optical disc 20, on which a computer program (i.e., a program product) is stored. When the computer program is run by a processor, it executes the methods provided in any of the aforementioned embodiments.

[0100] It should be noted that examples of computer-readable storage media may also include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other optical and magnetic storage media, which will not be elaborated here.

[0101] The computer-readable storage medium provided in the above embodiments of this application and the method provided in the embodiments of this application are based on the same inventive concept and have the same beneficial effects as the methods adopted, run or implemented by the applications stored therein.

[0102] It should be noted that: The term "module" is not intended to be limited to a specific physical form. Depending on the application, a module can be implemented as hardware, firmware, software, and / or a combination thereof. Furthermore, different modules may share common components or even be implemented using the same components. Clear boundaries may or may not exist between different modules.

[0103] The algorithms and displays provided herein are not inherently related to any particular computer, virtual device, or other equipment. Various general-purpose devices can also be used with the examples based on this. The required structure for constructing such devices is obvious from the above description. Furthermore, this application is not directed to any particular programming language. It should be understood that the content of this application described herein can be implemented using various programming languages, and the above description of specific languages ​​is for the purpose of disclosing the best mode of implementation of this application.

[0104] It should be understood that although the steps in the flowcharts of the accompanying figures are shown sequentially as indicated by the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the accompanying figures may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times, and their execution order is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the sub-steps or stages of other steps.

[0105] The above embodiments merely illustrate the implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. An automatic blade position calibration method, characterized in that, The method includes: After the blade reaches the limit switch position, the blade is controlled to run in a preset rotation direction. Based on the sensing block on the blade bearing, the blade passes through one or more proximity switches in the pitch system in sequence to obtain the first trigger angle and the first departure angle of each proximity switch. The propeller is controlled to run in the opposite direction of the preset rotation direction. Based on the induction block passing through each of the proximity switches in sequence, the second trigger angle and the second departure angle of each proximity switch are obtained. For each proximity switch, based on the pre-learned third trigger angle, third departure angle, fourth trigger angle, and fourth departure angle, a first error, a second error, a third error, and a fourth error corresponding to the proximity switch are obtained; the first error is the difference between the first trigger angle and the third trigger angle; the second error is the difference between the first departure angle and the third departure angle; the third error is the difference between the second trigger angle and the fourth trigger angle; and the fourth error is the difference between the second departure angle and the fourth departure angle. If the absolute values ​​of the first error, the second error, the third error, and the fourth error do not exceed their respective preset ranges, calculate the average value of the first error, the second error, the third error, and the fourth error of all the proximity switches. Calculate the difference between the physical position angle of the limit switch and the average value; The current position angle of the propeller is calibrated to the difference between the physical position angle of the limit switch and the average value.

2. The automatic blade position calibration method according to claim 1, characterized in that, The third trigger angle and the third departure angle are the trigger angle and departure angle of the sensing block when it passes the proximity switch during the pre-learning process, when the propeller is running in the preset rotation direction; the fourth trigger angle and the fourth departure angle are the trigger angle and departure angle of the sensing block when it passes the proximity switch during the pre-learning process, when the propeller is running in the opposite direction of the preset rotation direction.

3. The automatic blade position calibration method according to claim 1, characterized in that, The preset range is 0-4°.

4. The automatic blade position calibration method according to any one of claims 1-3, characterized in that, After the step of calibrating the current position angle of the propeller blade to the difference between the physical position angle of the limit switch and the average value, the method further includes: The propeller is controlled to run in a preset rotation direction. Based on the induction block passing through each of the proximity switches in sequence, the fifth trigger angle and the fifth departure angle of each proximity switch are obtained. The propeller is controlled to run in the opposite direction of the preset rotation direction. Based on the sequential passing of the sensing block through each of the proximity switches, the sixth trigger angle and the sixth departure angle of each proximity switch are obtained. For each proximity switch, a first deviation, a second deviation, a third deviation, and a fourth deviation are obtained; the first deviation is the difference between the fifth trigger angle and the third trigger angle; the second deviation is the difference between the fifth departure angle and the third departure angle; the third deviation is the difference between the sixth trigger angle and the fourth trigger angle; and the fourth deviation is the difference between the sixth departure angle and the fourth departure angle. If the absolute values ​​of the first deviation, the second deviation, the third deviation, and the fourth deviation all do not exceed a preset threshold, the calibration is deemed successful; otherwise, the calibration is deemed unsuccessful.

5. The automatic blade position calibration method according to claim 4, characterized in that, The preset threshold is 0.1°.

6. The automatic blade position calibration method according to any one of claims 1-3, characterized in that, If any of the absolute values ​​of the first error, the second error, the third error, or the fourth error exceed the preset range, the automatic calibration is exited, and the propeller is moved to the limit switch position.

7. The automatic blade position calibration method according to any one of claims 1-3, characterized in that, The physical angle position of the limit switch is 91°.

8. An automatic blade position calibration device, characterized in that, include: The first control module is used to control the blade to run in a preset rotation direction after the blade runs to the limit switch position, and to obtain the first trigger angle and the first departure angle of each proximity switch based on the induction block on the blade bearing passing through one or more proximity switches in the pitch system in sequence. The second control module is used to control the blade to run in the opposite direction of the preset rotation direction, and to obtain the second trigger angle and the second departure angle of each proximity switch based on the sequential passing of the sensing block through each proximity switch. The error acquisition module is used to acquire a first error, a second error, a third error, and a fourth error corresponding to the proximity switch based on the pre-learned third trigger angle, third departure angle, fourth trigger angle, and fourth departure angle; the first error is the difference between the first trigger angle and the third trigger angle; the second error is the difference between the first departure angle and the third departure angle; the third error is the difference between the second trigger angle and the fourth trigger angle; and the fourth error is the difference between the second departure angle and the fourth departure angle. The first calculation module is used to calculate the average value of the first error, the second error, the third error, and the fourth error of all the proximity switches, provided that the absolute values ​​of the first error, the second error, the third error, and the fourth error do not exceed their respective preset intervals. The second calculation module is used to calculate the difference between the physical position angle of the limit switch and the average value; The calibration module is used to calibrate the current position angle of the blade to the difference between the physical position angle of the limit switch and the average value.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, The computer program is executed by a processor to implement the automatic blade position calibration method as described in any one of claims 1-7.

10. An electronic device, characterized in that, The method includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the automatic blade position calibration method as described in any one of claims 1-7.

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