Wind turbine yaw brake control method, device and electronic equipment

Abstract

The application provides a wind turbine yaw brake control method and device and electronic equipment, and relates to the field of heat supply pipeline leakage diagnosis. The method realizes time sequence decoupling of hydraulic clamp braking and electromagnetic brake braking, realizes zero impact and zero stress locking of yaw braking through real-time sensing of the stress state of the yaw system, and thus solves the problems of tower head shaking vibration and tooth surface impact wear existing in the existing yaw brake control strategy.

Description

Technical Field

[0001] This invention relates to the field of yaw braking control for wind turbine generators, and in particular to a method, device, and electronic equipment for yaw braking control of wind turbine generators. Background Technology

[0002] The yaw system is the core actuator for wind turbine generators to achieve wind-following functionality. During yaw braking, traditional control strategies typically employ a combination of "on / off control + hydraulic clamp step pressure + electromagnetic brake instantaneous locking." Specifically, when the nacelle reaches the target wind-following angle, the yaw motor is de-energized, the electromagnetic brake (normally closed) instantaneously locks the motor shaft, and the hydraulic clamp pressure jumps from approximately 40% to 100% of the rated pressure. This control strategy suffers from the following problems: (1) Tower vibration and impact problem: The hydraulic clamp pressure rises stepwise and the electromagnetic brake locks instantly, causing the nacelle to be subjected to huge negative acceleration in a very short time (usually less than 0.2 seconds). This impact acts on the top of the tower in the form of inertial force, which excites the first bending mode of the tower and generates nodding vibration. Long-term operation will lead to loosening of the flange bolts and fatigue damage of the yaw gear ring of the tower.

[0003] (2) Tooth surface wear problem: When the electromagnetic brake is locked under the high pressure of the hydraulic clamp, the yaw gear and the gear ring are still subjected to a large aerodynamic bending moment load, and the tooth surface is in a hard stress state; the instantaneous locking of the electromagnetic brake forcibly restricts the small displacement of the transmission chain, resulting in the inability to release the tooth surface stress, forming a "hard tension" state, which accelerates the fatigue spalling of the tooth surface and the wear of the reducer gear. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a yaw braking control method, device and electronic equipment for wind turbines. The method achieves time decoupling of hydraulic clamp braking and electromagnetic braking, and realizes zero impact and zero stress locking of yaw braking by real-time sensing of the stress state of the yaw system, thereby solving the problems of tower head vibration and tooth surface impact wear in the existing yaw braking control strategy.

[0005] In a first aspect, embodiments of the present invention provide a yaw braking control method for a wind turbine, applied to a controller of a yaw system in a wind turbine; the yaw system further includes: a yaw motor, an electromagnetic brake device, and a hydraulic clamp; the method includes: The target yaw angle of the nacelle in the wind turbine is calculated using real-time collected wind direction data. After the yaw motor drives the nacelle to rotate to the pre-braking position corresponding to the target yaw angle, the hydraulic clamp is controlled to apply the corresponding target braking force to the nacelle according to the preset pressure segmented curve. When the yaw system is determined to be in a stress-free state by measuring the torque on the yaw motor shaft, the electromagnetic braking device is controlled to brake the yaw motor shaft, so that the cabin completes braking at the target yaw angle.

[0006] Optionally, after controlling the yaw motor to drive the nacelle to rotate to the pre-braking position corresponding to the target yaw angle, the method further includes: The creep speed of the yaw motor is calculated using the property parameters of the tower and impeller in the wind turbine. Once the nacelle is detected to have rotated to the pre-braking position, the yaw motor is controlled to linearly decrease from the rated speed to the creep speed. The electromagnetic brake device is controlled to be in the brake release state, and the hydraulic clamp is controlled to apply braking force according to the preset damping pressure.

[0007] Optionally, after controlling the yaw motor to linearly decrease from its rated speed to the creep speed, the method further includes: When the real-time speed of the yaw motor is detected to be less than the creep speed and the duration exceeds the preset duration threshold, the yaw motor is controlled to enter the zero-speed servo state; in the zero-speed servo state, the motor shaft of the yaw motor remains in a zero-speed locked state.

[0008] Optional, the preset process for pressure segmented curves includes: The target braking force of the hydraulic clamp is calculated using historical wind data collected within a preset historical period, and the target deceleration rate of the hydraulic clamp under the target braking force is calculated using the attribute parameters of the tower and impeller in the wind turbine. Using the target deceleration rate as a constraint, calculate the first and second pressure change rates of the hydraulic clamp under the target braking force. The pressure segment curve corresponding to the hydraulic clamp is constructed based on the first pressure change rate and the second pressure change rate.

[0009] Optionally, after controlling the hydraulic clamp to apply the corresponding target braking force to the cabin according to a preset pressure segmentation curve, the method further includes: The hydraulic clamp is controlled to maintain the target braking force according to the preset waiting time, and the electromagnetic brake device is controlled to maintain the brake release state. The motor shaft of the yaw motor is kept locked at zero speed.

[0010] Optionally, the stress-free state of the yaw system can be determined by the motor shaft torque of the yaw motor, including: The tooth surface stress threshold between the gear and gear ring of the yaw motor is calculated using the property parameters of the tower and impeller in the wind turbine. Collect the motor shaft torque of the yaw motor, and count the number of consecutive occurrences when the motor shaft torque is less than the tooth surface stress threshold according to a preset interval; If the number of consecutive occurrences exceeds a preset threshold, the yaw system is determined to be in a stress-free state.

[0011] Optionally, the motor shaft torque of the yaw motor can be collected, including: If a torque sensor is installed in the motor shaft of the yaw motor, the motor shaft torque is determined by the torque value collected in real time by the torque sensor. If the yaw motor is not equipped with a torque sensor, the target excitation torque of the yaw motor is calculated based on the tooth surface stress threshold. After the yaw motor is controlled to apply the target excitation torque to the motor shaft in zero-speed servo state, the motor shaft torque is calculated through the torque current corresponding to the yaw motor.

[0012] Optionally, the method further includes: The real-time hydraulic pressure of the hydraulic clamp at the target time is obtained by the pressure sensor in the hydraulic clamp, and the set hydraulic pressure of the hydraulic clamp at the target time is obtained by the pressure segmented curve. Calculate the pressure difference between the real-time hydraulic pressure and the set hydraulic pressure, and obtain the hydraulic deviation rate of the hydraulic clamp by calculating the ratio of the pressure difference to the set hydraulic pressure. If the hydraulic deviation rate is greater than the preset deviation threshold, the electromagnetic brake device is controlled to brake the motor shaft of the yaw motor, and the hydraulic clamp is controlled to apply the rated power to the engine room.

[0013] Secondly, the present invention provides a yaw braking control device for wind turbine generators, applied to the controller of the yaw system in a wind turbine generator; the yaw system further includes: a yaw motor, an electromagnetic brake device, and a hydraulic clamp; the device includes: Hydraulic soft brake control module: It is used to calculate the target yaw angle of the yaw system using real-time collected wind direction data, control the yaw motor to drive the yaw system to rotate to the pre-braking position corresponding to the target yaw angle, and then control the hydraulic clamp to apply the corresponding target braking force according to the preset pressure segmented curve. Stress-free shaft lock braking control module: When the yaw system is in a stress-free state, the module controls the electromagnetic brake device to brake the yaw motor, so that the yaw system completes braking at the target yaw angle, based on the torque of the yaw motor shaft.

[0014] Thirdly, embodiments of the present invention also provide an electronic device, which includes a processor and a memory. The memory stores computer-executable instructions that can be executed by the processor, and the processor executes the computer-executable instructions to implement the steps of the wind turbine yaw braking control method provided in the first aspect.

[0015] This invention provides a yaw braking control method, device, and electronic equipment for wind turbines. During the yaw braking control process, the target yaw angle of the nacelle in the wind turbine is first calculated using real-time acquired wind direction data. The yaw motor drives the nacelle to rotate to the pre-braking position corresponding to the target yaw angle. Then, the hydraulic clamp applies the corresponding target braking force to the nacelle according to a preset pressure segmented curve. Next, when the yaw system is determined to be in a stress-free state based on the motor shaft torque of the yaw motor, the electromagnetic brake device brakes the motor shaft of the yaw motor, allowing the nacelle to complete braking at the target yaw angle. This method achieves time decoupling between hydraulic clamp braking and electromagnetic braking, and realizes zero-impact and zero-stress locking of yaw braking by real-time sensing of the stress state of the yaw system, thereby solving the problems of tower head vibration and tooth surface impact wear in existing yaw braking control strategies.

[0016] Other features and advantages of the invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention are realized and obtained through the structures particularly pointed out in the description and the drawings.

[0017] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0018] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0019] Figure 1 A flowchart of a wind turbine yaw braking control method provided in an embodiment of the present invention; Figure 2 A flowchart of another wind turbine yaw braking control method provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of the structure of a wind turbine yaw braking control device provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention.

[0020] icon: 100 - Hydraulic soft brake control module; 200 - Stress-free shaft lock brake control module; 101 - Processor; 102 - Memory; 103 - Bus; 104 - Communication interface. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] To facilitate understanding of this embodiment, a yaw braking control method for wind turbines disclosed in this invention will first be introduced. This method is applied to the controller of the yaw system in a wind turbine. The yaw system also includes a yaw motor, an electromagnetic brake device, and a hydraulic clamp. In a specific scenario, the controller of the yaw system can be a PLC controller, and the speed of the yaw motor can be controlled by a frequency converter installed in the yaw system. The electromagnetic brake device is normally closed, meaning it is in a released state when energized. The pressure of the hydraulic clamp is controlled by a proportional relief valve installed in the yaw system. Based on this, the method is as follows: Figure 1 As shown, it includes: Step S101: Calculate the target yaw angle of the nacelle in the wind turbine using real-time collected wind direction data, control the yaw motor to drive the nacelle to rotate to the pre-braking position corresponding to the target yaw angle, and then control the hydraulic clamp to apply the corresponding target braking force to the nacelle according to the preset pressure segmented curve.

[0023] First, the target yaw angle of the wind turbine nacelle is calculated based on real-time collected wind direction and speed data. When the yaw motor drives the nacelle to move towards the target yaw angle, and the deviation between the current nacelle angle and the target yaw angle reaches a preset angle threshold, hydraulic flexible braking is executed according to the decoupled sequence of "pre-deceleration - soft boost - centering wait," while keeping the electromagnetic braking equipment in the energized and released state throughout the process. Specifically, this may include: Pre-deceleration stage: The yaw motor is linearly reduced from its rated speed to a low-speed creeping speed by the frequency converter, which prioritizes the dissipation of the high-speed rotational inertia of the yaw transmission chain; during this process, the hydraulic clamp maintains a low-pressure damping state, which provides basic damping to prevent speed runaway and does not introduce additional braking shock.

[0024] Hydraulic soft braking stage: When the yaw motor speed drops to the set low-speed threshold and remains stable for a preset time, the frequency converter switches to zero-speed servo mode, causing the yaw motor to actively maintain the zero-speed locked state of the motor shaft. At the same time, the braking pressure of the hydraulic clamp is controlled by the proportional relief valve, smoothly rising to the pressure value corresponding to the target braking force according to the preset pressure segmented curve, gradually dissipating the macroscopic rotational kinetic energy of the nacelle with gradual hydraulic friction. The pressure segmented curve constrains the rate of change of braking deceleration within the preset limit, fundamentally avoiding the first-order bending vibration of the tower caused by pressure step.

[0025] Wind turbine alignment waiting sub-stage: After the hydraulic clamp pressure stabilizes to the target braking force, the hydraulic clamp pressure, yaw motor zero-speed servo state and electromagnetic brake release state are maintained unchanged, and a waiting window of preset duration is entered, allowing the wind turbine in the nacelle to naturally align under the action of aerodynamic load, and initially releasing the aerodynamic bending moment load on the yaw tooth surface and transmission chain.

[0026] Step S102: When the yaw system is in a stress-free state as determined by the motor shaft torque of the yaw motor, control the electromagnetic braking device to brake the motor shaft of the yaw motor so that the cabin completes braking at the target yaw angle.

[0027] After the waiting window closes, the target braking force of the hydraulic clamp and the zero-speed servo state of the yaw motor remain unchanged. The torque sensing closed-loop judgment process is initiated. After confirming that the transmission chain teeth are in a low-stress free state, the electromagnetic brake mechanical locking is then executed, achieving complete decoupling of the braking sequence. Specifically, this includes: Stress sensing and cycle judgment: The actual output torque of the yaw motor shaft is acquired in real time through relevant torque sensing devices. The absolute value of the actual output torque is judged at fixed intervals to see if it is not greater than the preset low stress torque threshold. If the results of multiple consecutive judgments meet the threshold requirements, the contact surface between the yaw gear and the gear ring is judged to be in a free state without residual stress. If a single judgment exceeds the threshold, the acquisition and judgment are re-executed after a preset time. At the same time, an overtime protection mechanism is configured. When the judgment cycle continues to time out, the shaft locking action is forcibly executed and the "tooth surface stress release abnormality" event is recorded.

[0028] Zero-stress mechanical locking: The moment the transmission chain of the yaw system is determined to be in a stress-free state, the power supply to the electromagnetic brake coil is immediately cut off, and the normally closed electromagnetic brake is controlled to lock the motor shaft to complete mechanical locking; then the frequency converter is controlled to exit the zero-speed servo mode, the yaw motor is completely de-energized, and the hydraulic clamp maintains the target braking force unchanged, ultimately achieving zero-impact, zero-stress braking lock of the cabin at the target yaw angle.

[0029] Optionally, after controlling the yaw motor to drive the nacelle to rotate to the pre-braking position corresponding to the target yaw angle, the method further includes the following steps: Step S201: Calculate the creep speed of the yaw motor using the property parameters of the tower and impeller in the wind turbine.

[0030] By acquiring the structural property parameters of the wind turbine tower and the transmission system property parameters of the impeller and nacelle, and combining the transmission ratio and damping characteristics of the yaw drive chain, the low-speed creep speed of the yaw motor is calculated to match the dynamic constraints of the matching system. The tower structural property parameters include the first-order bending natural frequency of the tower and the equivalent moment of inertia at the top of the tower; the impeller and nacelle property parameters include the aerodynamic moment of inertia of the impeller, the overall moment of inertia of the nacelle, and the meshing damping coefficient of the yaw gear ring.

[0031] The calculation principle of creep speed is to ensure that the total rotational kinetic energy of the nacelle at this speed is lower than the excitation energy threshold of the first bending mode of the tower, while ensuring that the rate of change of the nacelle deceleration is always within the tower resonance avoidance range during the subsequent hydraulic pressurization process, so as to avoid the defects of poor adaptability of fixed low speed value and easy to cause secondary vibration, and achieve precise adaptation between the pre-deceleration endpoint and the inherent characteristics of the system.

[0032] Step S202: When the nacelle is detected to have rotated to the pre-braking position, the yaw motor is controlled to linearly decrease from the rated speed to the creep speed.

[0033] The deviation between the yaw angle of the engine compartment and the target yaw angle is collected in real time. When the deviation is reduced to the preset angle threshold, that is, when the engine compartment reaches the pre-braking position, the PLC controller outputs a linear deceleration command to the frequency converter, which controls the yaw motor to linearly reduce from the rated operating speed to the aforementioned calibrated creep speed according to the preset uniform deceleration slope, so that the engine compartment enters a low-speed creep operation state and completes the initial smooth dissipation of the high-speed rotational inertia of the yaw transmission chain.

[0034] The process is controlled by a frequency converter in a closed loop, keeping the motor energized and controllable throughout. This is different from the traditional on / off control that cuts off the motor power when the target angle is reached. It avoids the uncontrollable speed and initial braking shock caused by the motor stopping freely. The creep speed serves as a connection between pre-deceleration and subsequent hydraulic soft braking, ensuring the initial speed stability during the hydraulic clamp pressure increase process and eliminating the interference of speed fluctuations on braking smoothness.

[0035] Step S203: Control the electromagnetic brake device to be in the brake release state, and control the hydraulic clamp to apply braking force according to the preset damping pressure.

[0036] Throughout the entire process of yaw motor deceleration and low-speed creep, a power-on holding signal is continuously output to the electromagnetic brake device to control the electromagnetic brake device to always be in the brake release state and not participate in any braking action; at the same time, a constant control signal is output to the hydraulic clamp through the proportional relief valve to control the hydraulic clamp to continuously apply braking force according to the preset low-pressure damping pressure, providing basic rotational damping for the yaw drive chain.

[0037] In specific scenarios, the low-pressure damping pressure is set to 25%~30% of the rated braking pressure of the hydraulic clamp. It is only used to suppress the speed fluctuation caused by the backlash of the transmission chain and stabilize the engine speed under creep conditions. It will not produce significant braking deceleration and avoid prematurely introducing braking shock.

[0038] This stage achieves complete decoupling of the timing of electromagnetic braking and hydraulic braking by setting the state of "electromagnetic brake fully released + hydraulic clamp only providing damping", thus avoiding the impact superposition effect caused by the simultaneous action of the two in the traditional solution.

[0039] Optionally, after controlling the yaw motor to linearly decrease from the rated speed to the creep speed, the method further includes: when it is detected that the real-time speed of the yaw motor is less than the creep speed and the duration exceeds a preset duration threshold, controlling the yaw motor to be in a zero-speed servo state; wherein, in the zero-speed servo state, the motor shaft of the yaw motor remains in a zero-speed locked state.

[0040] In the specific implementation process, the motor speed is continuously and steadily verified by collecting the speed feedback signal of the encoder at the shaft end of the yaw motor in real time. When the real-time speed of the yaw motor is detected to be lower than the preset creep speed threshold, and the duration of the continuous maintenance of the low speed state reaches the preset steady-state duration threshold, the frequency converter is controlled to switch the drive operation mode, so that the yaw motor enters the zero-speed servo state.

[0041] The preset steady-state duration threshold is used to filter out the instantaneous speed drop caused by backlash in the transmission chain, speed sampling noise, and small fluctuations in aerodynamic load, thus avoiding incorrect mode switching; it ensures that the yaw transmission chain is in a stable low-speed condition before the hydraulic soft brake is started, eliminating the interference of initial speed fluctuations on subsequent S-shaped pressure ramp control and ensuring the controllability of braking deceleration.

[0042] In zero-speed servo mode, the frequency converter forms a closed-loop torque control based on the position encoder feedback, actively outputting dynamic balance torque to maintain the zero-speed lock-up state of the motor shaft, and actively constraining the rotation position of the nacelle through electrical means; during this process, the electromagnetic brake device remains energized and released, and the hydraulic clamp maintains a constant low-pressure damping pressure, without introducing mechanical braking force throughout the process.

[0043] Unlike the passive approach of "relying on mechanical friction to lock the motor after power failure" in traditional solutions, the motor remains energized and controllable in zero-speed servo mode. This can actively counteract the braking force fluctuations generated during the subsequent increase in hydraulic clamp pressure and maintain the stability of the engine compartment angle. At the same time, the torque current output by the inverter in this mode can directly map the load torque of the transmission chain, providing a data foundation for subsequent sensorless torque sensing and realizing the pre-connection between braking transition and stress determination.

[0044] Optionally, the preset process for the pressure segmented curve includes the following steps: Step S301: Calculate the target braking force of the hydraulic clamp using historical wind data collected within a preset historical time period, and calculate the target deceleration rate of the hydraulic clamp under the target braking force using the attribute parameters of the tower and impeller in the wind turbine.

[0045] Historical wind force data, such as wind speed and direction, collected within a preset historical period are obtained. Combined with the equivalent rotational inertia of the nacelle and rotor, the transmission ratio of the yaw drive chain, and the braking angle margin, the target braking force required to dissipate the rotational kinetic energy of the nacelle and balance the aerodynamic load during yaw braking is calculated, and the target braking pressure corresponding to the hydraulic clamp is obtained. At the same time, based on the structural attribute parameters of the wind turbine tower (including the first-order bending natural frequency of the tower and the equivalent rotational inertia of the tower top) and the damping characteristics of the transmission system, the excitation impact critical value of the first-order bending mode of the tower is derived. Using this as a constraint, the maximum allowable rate of deceleration change during the entire hydraulic braking process is determined, i.e., the target rate of deceleration change (e.g., 0.1g / s).

[0046] This step moves the physical constraints of tower vibration suppression to the design stage of the pressure curve, rather than passively reducing vibration during braking, thus avoiding the risk of tower head-nodding vibration caused by changes in hydraulic pressure from the root. At the same time, the target braking force is dynamically calibrated in combination with historical wind conditions, which can adapt to the load differences of different wind fields and seasons, avoiding the defects of insufficient adaptability of fixed pressure parameters.

[0047] Step S302: Using the target deceleration rate as a constraint, calculate the first pressure change rate and the second pressure change rate of the hydraulic clamp under the target braking force.

[0048] Using the target deceleration rate as a mandatory constraint condition throughout the process, and combining the working characteristics of different stages of hydraulic braking, the pressure change rate of two core sections during the pressure rise of the hydraulic clamp is calculated: the first pressure change rate corresponding to the initial stage of pressure rise (e.g., 0.5% of rated pressure / s), and the second pressure change rate corresponding to the main pressure rise stage (e.g., 5% of rated pressure / s).

[0049] The first pressure change rate corresponds to the initial slow rise section of the hydraulic clamp starting from low pressure damping pressure. At this time, the yaw transmission chain has just entered the zero speed lock state and there is still tooth backlash and small speed fluctuation. Therefore, a lower pressure rise slope is adopted to ensure that the initial braking force is applied smoothly and to avoid triggering tooth surface impact and transmission chain oscillation. The second pressure change rate corresponds to the main boost section after the zero-speed servo state stabilizes. At this time, the nacelle position has been electrically locked and the operating condition is stable. Therefore, a higher boost slope is adopted to accelerate the braking process and compress the overall braking time without breaking the deceleration change rate constraint.

[0050] Optionally, the third pressure change rate corresponding to the end of the pressurization phase can be further calculated. Its slope is of the same order of magnitude as the first pressure change rate. This is used to narrow the pressurization rate when the pressure approaches the target value, suppress pressure overshoot in the hydraulic system, and achieve smooth convergence at the end of braking. The pressure change rate of all sections must meet the following requirement: the nacelle angular deceleration change rate generated by the change in braking torque corresponding to the pressure change must never exceed the preset target deceleration change rate threshold.

[0051] Step S303: Construct the pressure segment curve corresponding to the hydraulic clamp based on the first pressure change rate and the second pressure change rate.

[0052] Based on the calculated first and second pressure change rates, the hydraulic clamp pressure segmented curve (i.e., the S-shaped pressure ramp control curve) is constructed by segmenting the curve according to the sequence of "initial gradual increase - main pressure increase - final gradual increase," resulting in continuous pressure throughout the entire process and a smooth transition in slope. The starting point of this curve matches the low-pressure damping pressure value during the pre-deceleration phase, and the ending point matches the target braking pressure value corresponding to the target braking force. There are no abrupt changes in pressure or pressure ramp at the junctions of each segment.

[0053] The segmented curve is pre-stored in the PLC controller as the control reference for hydraulic soft braking. It can also dynamically correct parameters online based on real-time wind speed and direction data to achieve flexible adaptive braking under different wind conditions. Compared with traditional step pressure or single slope control, this scheme effectively improves the response efficiency of hydraulic braking while strictly suppressing tower vibration and avoiding impact loads. It solves the technical contradiction of difficulty in balancing braking smoothness and braking speed in traditional schemes.

[0054] Optionally, after controlling the hydraulic clamp to apply the corresponding target braking force to the cabin according to a preset pressure segmentation curve, the method further includes the following steps: Step S401: Control the hydraulic clamp to maintain the target braking force according to the preset waiting time, and control the electromagnetic brake device to maintain the brake release state.

[0055] Once the hydraulic clamp pressure climbs along the preset segmented curve and stabilizes at the target braking pressure, the hydraulic clamp is controlled to maintain this target braking force unchanged. Simultaneously, the electromagnetic brake device remains in an energized braking release state throughout the entire process, without intervening in any braking action. This state continues for a preset waiting time window. The preset waiting time can be dynamically and adaptively calibrated based on real-time wind speed and aerodynamic load: when the real-time wind speed is high and the aerodynamic bending moment is large, the waiting window time is correspondingly extended to ensure sufficient stress release on the tooth surface; when the wind speed is low and the load is stable, the waiting time is correspondingly shortened, balancing braking efficiency and stress release effect, overcoming the limitation of poor adaptability of fixed durations.

[0056] Within this waiting window, the frictional torque provided by the hydraulic clamp can balance most of the aerodynamic rotational loads of the nacelle and the wind turbine, constraining the macroscopic rotation of the nacelle. At the same time, since the electromagnetic brake is fully released and the transmission chain is not mechanically locked, the yaw gear and gear ring can naturally fine-tune with the aerodynamic load within the meshing gap and the elastic deformation range of the transmission chain, driving the wind turbine to gradually align to the aerodynamic force balance position, pre-releasing the initial off-center bending moment and meshing stress on the tooth surface, and fundamentally avoiding the tooth surface hardening problem caused by direct mechanical locking under high pressure in traditional solutions.

[0057] Step S402: Control the yaw motor shaft to maintain a zero-speed locked state.

[0058] During the aforementioned waiting time window, the synchronous control yaw motor continuously operates in zero-speed servo mode. Through the fully closed-loop position control loop formed by the frequency converter and the shaft-end encoder, the zero-speed lock-up state of the motor shaft is actively maintained, and the drift of the nacelle yaw angle is constrained within the preset allowable range of wind accuracy.

[0059] Unlike the rigid locking of mechanical brakes, the electrical locking in zero-speed servo mode is a flexible constraint: on the one hand, it can counteract the small rotational torque generated during the wind turbine alignment process, preventing the nacelle angle from deviating from the target yaw angle beyond the allowable threshold and ensuring wind alignment accuracy; on the other hand, it does not completely restrict the micro-elastic deformation of the transmission chain, reserving space for the natural release of tooth surface stress, thus resolving the technical contradiction in traditional solutions where locking positioning accuracy and tooth surface stress release are difficult to balance. Simultaneously, in zero-speed servo mode, the inverter can output motor torque current signals in real time, providing a reusable detection channel for subsequent sensorless torque sensing, achieving pre-reuse of operating condition holding and stress detection capabilities.

[0060] Optionally, determining whether the yaw system is in a stress-free state by measuring the motor shaft torque of the yaw motor includes the following steps: Step S501: Calculate the tooth surface stress threshold between the gear and gear ring of the yaw motor using the property parameters of the tower and impeller in the wind turbine.

[0061] The structural property parameters of the wind turbine tower and rotor, and the transmission characteristic parameters of the yaw transmission system are obtained. The structural property parameters include the rotor aerodynamic equivalent bending moment and the moment of inertia at the top of the tower. The transmission characteristic parameters include the total transmission ratio of the yaw transmission chain, the gear meshing stiffness coefficient, the allowable contact stress of the tooth surface, and the fatigue safety factor. Based on the above parameters, a transmission mapping model between the tooth surface contact stress and the motor shaft output torque is constructed. The critical stress value of the tooth surface in a low-stress free state and where the meshing residual stress does not cause fatigue damage is derived. Then, the torque is converted back to the yaw motor shaft end through the transmission chain torque conversion relationship to obtain the motor shaft torque threshold for the corresponding tooth surface stress determination.

[0062] This threshold is not a fixed empirical value, but a quantitative calibration result that combines the unit's own structural parameters and tooth surface fatigue constraints. It can be adapted to different models and different years of operation, solving the shortcomings of traditional solutions that rely on experience to set the locking time and cannot match the actual stress state of the tooth surface. It ensures the scientific nature of zero-stress locking from the judgment benchmark level.

[0063] Step S502: Collect the motor shaft torque of the yaw motor, and count the number of consecutive occurrences when the motor shaft torque is less than the tooth surface stress threshold according to the preset interval.

[0064] The torque output of the yaw motor shaft is collected in real time by the relevant torque sensing unit of the yaw motor. The absolute value of the torque is compared with the aforementioned tooth surface stress threshold according to the preset fixed sampling period, and the number of consecutive occurrences of torque value less than or equal to the tooth surface stress threshold is counted. If the absolute value of the torque in a single sampling exceeds the threshold, the current consecutive count is immediately cleared and the cumulative statistics are restarted.

[0065] In specific scenarios, the torque sensing unit can achieve dual-mode acquisition: units equipped with shaft-end torque sensors directly read the sensor torque value; units without torque sensors obtain the equivalent motor shaft torque by converting the output torque current in the zero-speed servo mode of the frequency converter. Both acquisition methods are incorporated into a unified judgment logic.

[0066] This step employs a continuous accumulation + over-limit reset verification mechanism, which can effectively filter out instantaneous torque fluctuations caused by wind load pulsation, micro-vibration of transmission chain tooth backlash, and sampling noise. It avoids misjudgments caused by single low torque values, ensuring that the identified state is a truly stable low-stress state of the transmission chain, rather than an instantaneous operating condition fluctuation, thus significantly improving the anti-interference capability and accuracy of stress state determination.

[0067] Step S503: If the number of consecutive occurrences exceeds the preset threshold, the yaw system is determined to be in a stress-free state.

[0068] When the number of consecutive occurrences of the torque obtained from statistics exceeds the preset threshold, it is determined that the meshing surface of the gear and gear ring of the current yaw system is in a low-stress free state, the residual meshing stress of the transmission chain has been fully released, and the prerequisite for zero-stress locking is met.

[0069] Simultaneously, an overtime fallback protection mechanism is configured: if the stress judgment cycle continues to run for longer than the preset maximum waiting time and still fails to meet the continuous compliance conditions, the judgment process will be forcibly terminated, triggering subsequent shaft locking actions and simultaneously recording abnormal events of tooth surface stress release, thus avoiding the braking process from stalling indefinitely under extreme wind conditions, and balancing braking reliability and operating efficiency.

[0070] Optionally, the motor shaft torque of the yaw motor can be collected, including the following steps: Step S601: If a torque sensor is installed in the motor shaft of the yaw motor, the motor shaft torque is determined by the torque value collected in real time by the torque sensor.

[0071] If the yaw motor has a torque sensor mounted coaxially on its shaft end, the actual torque of the motor shaft is obtained by direct sensor acquisition: the static output torque value of the motor shaft is collected in real time by the torque sensor, and the corresponding analog or digital signal is transmitted to the PLC controller. After digital filtering, it is directly used as the basis for determining the torque of the motor shaft.

[0072] This is the preferred implementation method. The torque sensor is coaxially connected between the motor output shaft and the reducer input shaft, which can directly and without distortion reflect the true load state of the transmission chain. It has high detection accuracy, low response delay, and is not affected by the temperature drift or aging of the motor's electrical parameters. At the same time, the detection process is performed under zero-speed servo steady-state conditions, which can completely eliminate the interference of dynamic rotational inertia on the torque detection results, further improving the accuracy of identifying residual stress on the tooth surface.

[0073] Step S602: If the yaw motor is not equipped with a torque sensor, the target excitation torque of the yaw motor is calculated based on the tooth surface stress threshold, and the yaw motor is controlled to apply the target excitation torque to the motor shaft in the zero-speed servo state. Then, the motor shaft torque is calculated through the torque current corresponding to the yaw motor.

[0074] If the yaw system is not equipped with an independent torque sensor, a micro-motion excitation method based on the zero-speed servo capability of the inverter is used to indirectly calculate the equivalent output torque of the motor shaft: First, combining the preset tooth surface stress threshold, the rated torque parameters of the motor and the inherent torque constant, the target excitation torque amplitude required for detection is determined by reverse calculation, and the excitation torque amplitude is controlled within a safe range that will not cause additional stress damage to the tooth surface; then, based on the yaw motor continuously maintaining a zero-speed servo state, the inverter outputs a small amplitude excitation torque with a smooth alternating waveform to the motor shaft, and the actual torque current of the inverter output circuit is collected in real time. The equivalent actual output torque of the motor shaft is calculated based on the linear mapping relationship between motor torque and current.

[0075] The amplitude of the target excitation torque in the above steps is calculated in conjunction with the tooth surface stress threshold. This ensures that the excitation signal is sufficient to overcome the backlash in the transmission chain and accurately reflects the residual stress state of the meshing surface, while avoiding excessive excitation load that could introduce additional tooth surface impact, thus balancing detection sensitivity and braking safety. The excitation process can use a triangular wave with a continuous, equal slope alternating waveform to replace the step torque output, avoiding transmission chain oscillations caused by the excitation process. Furthermore, the detection process maintains zero-speed position constraints throughout, preventing nacelle angle drift and ensuring no impact on the final wind accuracy.

[0076] Optionally, the method further includes the following steps: Step S701: Obtain the real-time hydraulic pressure of the hydraulic clamp at the target time through the pressure sensor in the hydraulic clamp, and obtain the set hydraulic pressure of the hydraulic clamp at the target time through the pressure segmented curve.

[0077] Throughout the entire braking and pressure maintenance process of the hydraulic clamp according to the preset pressure segmented curve, a fixed high-frequency sampling frequency is used to collect the real-time hydraulic pressure value at the target moment through the pressure sensor configured in the hydraulic clamp's oil circuit. Simultaneously, the theoretical set hydraulic pressure value corresponding to the target moment is matched from the preset pressure segmented curve to form a synchronous data pair of "target set value - actual feedback value" for subsequent deviation verification. The sampling process is equipped with digital filtering to filter out inherent pressure pulsations and sampling noise interference from the hydraulic system. The hydraulic pressure is set to be dynamically updated with the braking process, fully covering the pressure verification of the entire stage of initial gradual increase, main pressure increase, and steady-state maintenance, rather than performing single-point verification only at the steady-state endpoint, achieving closed-loop pressure monitoring without blind spots throughout the entire braking process.

[0078] Step S702: Calculate the pressure difference between the real-time hydraulic pressure and the set hydraulic pressure, and obtain the hydraulic deviation rate of the hydraulic clamp by calculating the ratio of the pressure difference to the set hydraulic pressure.

[0079] The absolute difference between the real-time hydraulic pressure and the set hydraulic pressure at the same target time is calculated. The hydraulic deviation rate is calculated by the ratio of this pressure difference to the current set hydraulic pressure. The pressure following performance and operational health status of the hydraulic system are quantitatively characterized by the relative deviation index.

[0080] This step uses relative deviation rate instead of absolute pressure difference as the judgment index, which can be adapted to the control accuracy requirements of different pressure sections during braking: the absolute deviation allowed in the low-pressure damping stage is smaller, and the absolute deviation allowed in the high-pressure braking stage is larger. The relative deviation rate unifies the fault judgment scale of the whole process, and can more sensitively identify the small leakage in the low-pressure section and the pressure overshoot in the high-pressure section, thereby improving the rationality and accuracy of anomaly judgment.

[0081] Step S703: If the hydraulic deviation rate is greater than the preset deviation threshold, control the electromagnetic brake device to brake the motor shaft of the yaw motor and control the hydraulic clamp to apply the rated power to the engine room.

[0082] When the calculated hydraulic deviation rate exceeds the preset deviation threshold, it is determined that the hydraulic system has an abnormality such as control failure, oil circuit leakage, or proportional relief valve failure. The current flexible braking control process is immediately terminated, and a dual-redundancy emergency braking mechanism is triggered: on the one hand, the electromagnetic brake device is de-energized and locked, and the mechanical locking of the motor shaft is quickly completed; on the other hand, the hydraulic clamp is directly pressurized to the full customized power to provide a second layer of braking redundancy to constrain the position of the engine compartment; at the same time, a hydraulic system fault alarm signal is generated, and the operating condition data and pressure data at the time of the fault are recorded for operation and maintenance traceability.

[0083] This emergency mechanism can be triggered at any stage of flexible braking, breaking through the limitation of traditional protection that only takes effect in steady state. It adopts a dual redundancy scheme of "electromagnetic mechanical locking + full-pressure hydraulic braking" to ensure that the cabin will not yaw out of control due to insufficient braking force when the hydraulic system is abnormal. While ensuring the benefits of flexible braking in reducing vibration and wear, it also safeguards the bottom line of system safety.

[0084] The complete flow of the wind turbine yaw braking control method in the above embodiments is as follows: Figure 2 As shown, this process is executed after the yaw end command is triggered. This command can be a wind alignment completion signal output by the wind turbine's main control system or a manually issued yaw stop command. Through multi-stage timing control combined with conditional branch judgment, low-impact, low-residual-stress locking of the yaw drivetrain is achieved. A fault fallback mechanism is also configured to balance braking smoothness and equipment safety. The specific process is as follows: Phase 1: Pre-deceleration phase.

[0085] Upon receiving the yaw end command, the system first enters the pre-deceleration phase. The yaw motor is controlled to perform speed reduction control, gradually dissipating the rotational kinetic energy of the nacelle and impeller, reducing the yaw speed to a preset low-speed range. This reduces the initial impact load for the subsequent hydraulic soft braking process and avoids instantaneous torque impact caused by directly applying braking pressure.

[0086] In a specific scenario, the wind turbine's main control system can issue a yaw termination command when it detects a yaw angle deviation of less than 0.5°. Upon receiving the command, the PLC controller sends a deceleration command to the frequency converter. The frequency converter controls the yaw motor speed to decrease linearly from its rated speed to 0.1 rpm. During this process, the hydraulic clamp maintains a low-pressure damping state at 30% of its rated pressure, and the electromagnetic brake remains energized and released. The purpose of this step is to eliminate the high-speed rotational inertia of the motor and drivetrain.

[0087] Second stage: Hydraulic soft braking stage.

[0088] After pre-deceleration, the system enters the hydraulic soft braking phase. A pre-generated pressure segmented curve is invoked, and the hydraulic clamps are controlled to apply braking force to the nacelle according to the temporal slope of the segmented curve. The segmented curve is constructed with the target deceleration rate under tower vibration reduction constraints as the boundary condition. By adopting a segmented pressure increase strategy, it can suppress sudden deceleration changes during the braking process, avoid the risk of inducing tower vibration, and smoothly consume the unit's remaining rotational kinetic energy.

[0089] In a specific scenario, when the encoder feedback indicates that the motor speed has dropped below 0.1 rpm and remains stable for 0.5 seconds, the inverter switches to zero-speed servo mode to maintain the motor shaft at zero speed. The PLC controller sends a control signal to the proportional relief valve through the analog output module, controlling the hydraulic clamp pressure to smoothly rise from 25% to 80% of the rated pressure according to a preset S-curve.

[0090] The S-curve parameters can be set as follows: total rise time 2.0 seconds, initial slope 0.5% / s, middle slope 5% / s, and final slope 0.5% / s. The electromagnetic brake remains energized and released.

[0091] This step utilizes the high friction of the hydraulic clamp to dissipate the macroscopic kinetic energy of the nacelle. Due to the smooth pressure change, the rate of deceleration change is controlled within 0.1g / s, and the vibration amplitude at the top of the tower is significantly reduced.

[0092] Phase 3: Zero speed maintenance and cabin wind-fighting phase.

[0093] Once the hydraulic clamp pressure reaches the target braking force, it enters a zero-speed holding phase against the wind in the nacelle. The hydraulic clamp is controlled to maintain the target braking force output, while the electromagnetic brake is kept in the brake release state. Simultaneously, the yaw motor is controlled to maintain a zero-speed lock-in state. Within a preset waiting time window, the transmission chain is allowed to make slight adaptive adjustments within the tooth backlash and elastic deformation range according to the aerodynamic load, so that the nacelle gradually approaches the aerodynamic force balance position, pre-releasing most of the residual meshing stress on the gear teeth.

[0094] In a specific scenario, after the hydraulic pressure reaches 80% and stabilizes, a 3-second waiting window is entered. During this window, the frequency converter maintains zero-speed servo operation, the electromagnetic brake remains released, and the hydraulic clamp maintains 80% high-pressure locking of the engine compartment.

[0095] Phase 4: Torque perception and stress determination phase.

[0096] After the waiting period ends, the torque sensing and stress determination stage begins. A dual-mode approach is used to acquire the yaw motor shaft torque: if a torque sensor is configured, the sensor-acquired torque is read directly; if no sensor is available, a small target excitation torque is applied, and the equivalent motor shaft torque is calculated based on the motor torque current. The acquired motor shaft torque is then compared with a pre-calibrated tooth surface stress threshold, and the number of consecutive determinations where the torque is less than the tooth surface stress threshold is continuously counted.

[0097] Branch condition determination: Execute the logic check of "three consecutive judgments of torque < threshold". If the judgment is correct, proceed to the fifth stage: zero-stress shaft locking. At this time, it is determined that the residual stress on the yaw transmission chain tooth surface has been fully released, and the electromagnetic brake device is controlled to complete the mechanical locking of the motor shaft, realizing stress-free shaft locking. After the shaft locking is completed, the entire yaw braking process ends, that is, the braking is completed.

[0098] If the condition is not met, the timeout protection and alarm branch will be triggered. If the condition that the torque is less than the threshold three times consecutively cannot be met within the preset maximum waiting period, the tooth surface stress release is determined to be abnormal, and the emergency backup braking logic will be executed. For example, the electromagnetic brake will be forcibly locked, the hydraulic clamp will output the rated power, and a fault alarm will be generated and the working condition log will be stored to avoid the process from being stopped indefinitely.

[0099] In a specific scenario, after the waiting window ends, the yaw system enters the torque sensing cycle. The hydraulic clamp pressure remains constant at 80%. The PLC controller directly reads the torque sensor value installed on the motor shaft. It checks every second whether the torque sensor value is less than 2% of the rated torque; if it is less than the threshold, it is considered a "low-stress free state." If it is determined to be in a "low-stress free state" three times consecutively, it enters the fifth stage.

[0100] If the torque sensor reading in any judgment exceeds 2% of the rated torque, residual stress is determined to exist, and the system waits for 1 second before rereading and judging. If this cycle continues for more than 10 seconds without completing three consecutive low-stress judgments, timeout protection is triggered, the fifth stage is forcibly executed, and the "tooth surface stress release abnormality" event is recorded.

[0101] In real-world scenarios, the following protection strategies can also be set according to security requirements: Wind speed change protection strategy: During the torque sensing and stress determination stage, the wind conditions are monitored in real time using relevant anemometers; if the wind speed changes by more than 8 m / s or the wind direction changes by more than 30° within 1 second, the PLC controller will immediately stop the current determination cycle and re-execute the third stage.

[0102] Position drift protection: In the third or fourth stage, the nacelle angle is monitored in real time by the encoder; if the nacelle angle drifts by more than ±0.5°, the PLC controller will stop the current process and return to re-execute the second stage.

[0103] Pressure anomaly protection: The pressure sensor provides real-time feedback on the hydraulic pressure. If the deviation from the set value exceeds ±10%, the PLC controller determines that the hydraulic system is faulty, immediately switches to the traditional emergency stop mode (the electromagnetic brake device locks up, and the hydraulic clamp pressure is stepped up to 100%), and issues a fault alarm.

[0104] As can be seen from the above-mentioned yaw braking control method for wind turbines, this method achieves time-sequential decoupling of hydraulic clamp braking and electromagnetic braking, and realizes zero-impact and zero-stress locking of yaw braking by real-time sensing of the stress state of the yaw system, thereby solving the problems of tower head vibration and tooth surface impact wear in the existing yaw braking control strategy.

[0105] Corresponding to the above embodiments of the wind turbine yaw braking control method, this invention also provides a wind turbine yaw braking control device, applied to the controller of the yaw system in a wind turbine; the yaw system further includes: a yaw motor, an electromagnetic brake device, and a hydraulic clamp; as shown Figure 3 As shown, the device includes: Hydraulic soft brake control module 100: It is used to calculate the target yaw angle of the yaw system using real-time collected wind direction data, control the yaw motor to drive the yaw system to rotate to the pre-braking position corresponding to the target yaw angle, and then control the hydraulic clamp to apply the corresponding target braking force according to the preset pressure segmented curve. Stress-free shaft lock braking control module 200: When the yaw system is in a stress-free state, the electromagnetic brake device is controlled to brake the yaw motor, so that the yaw system completes braking at the target yaw angle, based on the motor shaft torque of the yaw motor.

[0106] As can be seen from the above-mentioned wind turbine yaw braking control device, the device achieves time-sequential decoupling of hydraulic clamp braking and electromagnetic braking, and realizes zero-impact and zero-stress locking of yaw braking by sensing the stress state of the yaw system in real time, thereby solving the problems of tower head vibration and tooth surface impact wear in the existing yaw braking control strategy.

[0107] The wind turbine yaw braking control device provided in this embodiment of the invention has the same implementation principle and technical effect as the aforementioned wind turbine yaw braking control method embodiment. For the sake of brevity, any parts not mentioned in the device embodiment can be referred to the corresponding content in the aforementioned wind turbine yaw braking control method embodiment.

[0108] This embodiment also provides an electronic device, the structural schematic diagram of which is shown below. Figure 4 As shown, the device includes a processor 101 and a memory 102; wherein, the memory 102 is used to store one or more computer instructions, which are executed by the processor to implement the steps of the wind turbine yaw braking control method described above.

[0109] Figure 4 The electronic device shown also includes a bus 103 and a communication interface 104, with the processor 101, communication interface 104 and memory 102 connected via the bus 103.

[0110] The memory 102 may include high-speed random access memory (RAM) and may also include non-volatile memory, such as at least one disk storage device. The bus 103 may be an ISA bus, PCI bus, or EISA bus, etc. The bus can be divided into address bus, data bus, control bus, etc. For ease of representation, Figure 4 The symbol is represented by a single double-headed arrow, but this does not mean that there is only one bus or one type of bus.

[0111] The communication interface 104 is used to connect to at least one user terminal and other network units through a network interface, and to send encapsulated IPv4 packets or IPv4 packets to the user terminal through the network interface.

[0112] Processor 101 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 101 or by instructions in software form. The processor 101 can be a general-purpose processor, including a Central Processing Unit (CPU), a Network Processor (NP), etc.; it can also be a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field-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 disclosure. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the methods disclosed in the embodiments of this disclosure can be directly manifested as execution by a hardware decoding processor, or execution by a combination of hardware and software modules in the decoding processor. The software module can reside in a mature storage medium in the art, such as random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, or registers. This storage medium is located in memory 102. The processor 101 reads the information in memory 102 and, in conjunction with its hardware, completes the steps of the method described in the foregoing embodiments.

[0113] This invention also provides a storage medium storing a computer program, which, when executed by a processor, performs the steps of the wind turbine yaw braking control method described in the foregoing embodiments.

[0114] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, devices, and methods can be implemented in other ways. The system embodiments described above are merely illustrative. For example, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. Furthermore, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Additionally, the coupling or direct coupling or communication connection shown or discussed may be through some communication interfaces; the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.

[0115] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0116] In addition, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0117] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a processor-executable, non-volatile, computer-readable storage medium. Based on this understanding, the technical solution of this invention, essentially, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, electronic device, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0118] Finally, it should be noted that the above-described embodiments are merely specific implementations of the present invention, used to illustrate the technical solutions of the present invention, and not to limit it. The scope of protection of the present invention is not limited thereto. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments within the technical scope disclosed in the present invention, or make equivalent substitutions for some of the technical features; and these modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A wind turbine generator yaw brake control method characterized by, A controller used in the yaw system of wind turbines; The yaw system further includes: a yaw motor, an electromagnetic brake device, and a hydraulic clamp; the method includes: The target yaw angle of the nacelle in the wind turbine is calculated using real-time collected wind direction data. After the yaw motor drives the nacelle to rotate to the pre-braking position corresponding to the target yaw angle, the hydraulic clamp is controlled to apply the corresponding target braking force to the nacelle according to the preset pressure segmented curve. When the yaw system is determined to be in a stress-free state by the motor shaft torque of the yaw motor, the electromagnetic braking device is controlled to brake the motor shaft of the yaw motor, so that the cabin completes braking at the target yaw angle.

2. The wind turbine generator yaw brake control method according to claim 1, characterized by, After controlling the yaw motor to drive the cabin to rotate to the pre-braking position corresponding to the target yaw angle, the method further includes: The creep speed of the yaw motor is calculated using the property parameters of the tower and impeller in the wind turbine unit; When the cabin is detected to have rotated to the pre-braking position, the yaw motor is controlled to linearly decrease from the rated speed to the creep speed. The electromagnetic brake device is controlled to be in the brake release state, and the hydraulic clamp is controlled to apply braking force according to the preset damping pressure.

3. The wind turbine yaw braking control method according to claim 2, characterized in that, After controlling the yaw motor to linearly decrease from its rated speed to the creeping speed, the method further includes: When it is detected that the real-time speed of the yaw motor is less than the creep speed and the duration exceeds a preset duration threshold, the yaw motor is controlled to be in a zero-speed servo state; wherein, in the zero-speed servo state, the motor shaft of the yaw motor is kept in a zero-speed locked state.

4. The yaw braking control method for wind turbine generators according to claim 1, characterized in that, The process of presetting the pressure segmented curve includes: The target braking force of the hydraulic clamp is calculated using historical wind data collected within a preset historical period, and the target deceleration rate of the hydraulic clamp under the target braking force is calculated using the attribute parameters of the tower and impeller in the wind turbine. Using the target deceleration rate as a constraint, calculate the first pressure change rate and the second pressure change rate of the hydraulic clamp under the target braking force; The pressure segmented curve corresponding to the hydraulic clamp is constructed based on the first pressure change rate and the second pressure change rate.

5. The wind turbine yaw braking control method according to claim 1, characterized in that, After controlling the hydraulic clamp to apply a corresponding target braking force to the engine room according to a preset pressure segmentation curve, the method further includes: The hydraulic clamp is controlled to maintain the target braking force according to the preset waiting time, and the electromagnetic brake device is controlled to maintain the brake release state. The motor shaft of the yaw motor is kept in a zero-speed locked state.

6. The yaw braking control method for wind turbine generators according to claim 1, characterized in that, Determining whether the yaw system is in a stress-free state by measuring the motor shaft torque of the yaw motor includes: The tooth surface stress threshold between the gear and the gear ring of the yaw motor is calculated using the property parameters of the tower and impeller in the wind turbine. The motor shaft torque of the yaw motor is collected, and the number of consecutive occurrences when the motor shaft torque is less than the tooth surface stress threshold is counted at preset intervals. If the number of consecutive occurrences exceeds a preset threshold, the yaw system is determined to be in a stress-free state.

7. The wind turbine yaw braking control method according to claim 6, characterized in that, The acquisition of the motor shaft torque of the yaw motor includes: If the yaw motor is equipped with a torque sensor in the motor shaft, the torque of the motor shaft is determined by the torque value collected in real time by the torque sensor. If the yaw motor is not equipped with the torque sensor, the target excitation torque of the yaw motor is calculated based on the tooth surface stress threshold, and the yaw motor is controlled to apply the target excitation torque to the motor shaft in zero-speed servo state. Then, the motor shaft torque is calculated through the torque current corresponding to the yaw motor.

8. The yaw braking control method for wind turbine generators according to claim 1, characterized in that, The method further includes: The real-time hydraulic pressure of the hydraulic clamp at the target time is obtained by the pressure sensor in the hydraulic clamp, and the set hydraulic pressure of the hydraulic clamp at the target time is obtained by the pressure segmented curve. Calculate the pressure difference between the real-time hydraulic pressure and the set hydraulic pressure, and obtain the hydraulic deviation rate of the hydraulic clamp by calculating the ratio of the pressure difference to the set hydraulic pressure. If the hydraulic deviation rate is greater than a preset deviation threshold, the electromagnetic brake device is controlled to brake the motor shaft of the yaw motor, and the hydraulic clamp is controlled to apply additional power to the engine room.

9. A yaw braking control device for a wind turbine generator, characterized in that, A controller used in the yaw system of wind turbines; The yaw system further includes: a yaw motor, an electromagnetic brake device, and a hydraulic clamp; the device includes: Hydraulic soft brake control module: used to calculate the target yaw angle of the yaw system using real-time collected wind direction data, control the yaw motor to drive the yaw system to rotate to the pre-braking position corresponding to the target yaw angle, and then control the hydraulic clamp to apply the corresponding target braking force according to the preset pressure segmented curve; Stress-free shaft lock braking control module: When the yaw system is in a stress-free state as determined by the motor shaft torque of the yaw motor, the module controls the electromagnetic brake device to brake the yaw motor, so that the yaw system completes braking at the target yaw angle.

10. An electronic device, characterized in that, The electronic device includes a processor and a memory, the memory storing computer-executable instructions that can be executed by the processor, the processor executing the computer-executable instructions to implement the steps of the wind turbine yaw braking control method according to any one of claims 1 to 8.

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