A Yaw Optimization Control System for a Wind Turbine Generator and Its Control Method

Abstract

An embodiment of the present invention relates to a yaw optimization control system for a wind turbine generator and its control method. The system includes a yaw control module, an information interaction interface module, a yaw brake module, and a yaw drive module, and is used to optimize the control of the components related to the yaw mechanism of an existing wind turbine generator. The technical solution implemented by the present invention can achieve soft start and stop control of the yaw motor, avoiding the current and mechanical impacts on the yaw motor during the start and stop processes; achieving gentle meshing of the gear clearance between the large yaw gear and the small drive gear before yaw start, avoiding mechanical impacts caused by gear clearance during the start process; achieving dynamic control of the braking force of the yaw braking system during the yaw process, reducing mechanical wear and noise; and at the same time, achieving dynamic real-time control of the motor output torque during the yaw process to complete precise real-time wind alignment control, improving the stability of the yaw system of the wind turbine generator, thereby improving the maximum wind energy capture capacity of the wind turbine generator.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of new energy power generation, and in particular, to a yaw optimization control system for a wind turbine generator and a control method thereof. Background Art

[0002] While the global energy demand continues to grow, the contradiction between economic development and environmental resources has become increasingly prominent. Developing a low-carbon economy, building an ecological civilization, and achieving sustainable development have become the common consensus of human society. As a clean and renewable energy resource with rich reserves and wide distribution, wind energy has become an important strategy for the sustainable economic and social development of countries around the world. In recent years, with the rapid development of wind power generation technology, the installed capacity of wind power has increased explosively. As the operation time of the units increases, in order to improve the efficiency of the units, the demand for the maintenance and transformation of operating wind power equipment has become increasingly prominent, and the requirements have also become higher and higher.

[0003] The maximum wind energy capture ability of a wind turbine generator depends on the accurate and real-time tracking of the wind direction by the unit. The yaw system is the execution system for realizing the real-time and accurate wind alignment of the wind turbine generator and is a key component of a horizontal-axis wind turbine generator. For large wind turbine generators, when the function of the yaw system fails, the unit will inevitably stop running, resulting in benefit losses. By studying the yaw mechanism of the wind turbine generator, it is found that there are large design differences and room for optimization and improvement in the control system of the yaw mechanism, and the control system performance of the yaw mechanism determines the safety of the wind turbine unit.

[0004] As the wind direction of the wind turbine generator changes continuously, the yaw system needs to perform wind alignment control to obtain more wind energy and increase power generation. However, when the wind direction fluctuates frequently and violently, the yaw system's execution mechanism will operate frequently, which will increase the working intensity of mechanical mechanisms such as yaw bearings. Once a failure occurs, the loss to the benefit of the wind farm will be huge. Since the domestic wind power industry has developed to date, for the wind turbine generators put into operation, the early design scheme of the yaw system was that when the yaw mechanical mechanism performed the yaw action, the asynchronous motor used for yaw drive adopted a control method of direct starting with a contactor. With the development of wind power control technology, a better soft starter or frequency converter is now used to control the start and stop of the yaw motor. However, the mechanical friction and starting current impact on the motor during the yaw process of the wind turbine generator both affect the smooth operation of the wind turbine generator and cause damage to the unit in terms of vibration and mechanical shock. Summary of the Invention

[0005] Based on the above situation of the prior art, the purpose of the embodiments of the present invention is to provide a yaw optimization control system and its control method for a wind turbine generator. Aiming at the yaw mechanical structure of the prior art, the yaw braking mechanism is optimized and controlled to change the working state of the yaw mechanism in the yaw stop stage and the yaw running stage, and the electromagnetic torque of the yaw motor and the friction force of the yaw brake are adjusted in real time to optimize the mechanical friction in the yaw process of the wind turbine generator and reduce the vibration and noise of the unit caused by yaw.

[0006] To achieve the above object, according to one aspect of the present invention, a yaw optimization control system for a wind turbine generator is provided, including a yaw control module, an information interaction interface module, a yaw braking module, and a yaw drive module;

[0007] The output of the yaw control module is connected to the yaw braking module and the yaw drive module. The yaw control module is used to execute the yaw alignment command, coordinate the actions of the yaw braking module, and issue a motion control instruction to the yaw drive module to complete the motion control of the yaw motor and achieve yaw alignment;

[0008] The information interaction interface module is connected to the yaw control module, and is used to transmit the yaw alignment command to the yaw control module and feedback the working state of the yaw control module.

[0009] Further, the yaw braking module includes a yaw hydraulic valve and a yaw brake;

[0010] The yaw braking module adjusts the hydraulic pressure of the brake caliper of the yaw brake by changing the state of the yaw hydraulic valve to control the action state of the yaw braking module.

[0011] Further, the yaw drive module includes a motion control unit, a yaw motor, and a motor encoder;

[0012] The motion control unit executes the motion control command, dynamically adjusts the torque and speed output by the yaw motor, and feeds back the yaw motor encoder information to the yaw control module.

[0013] According to the second aspect of the present invention, a yaw control system for a wind turbine generator is provided, including a yaw optimization control system, a main controller of the wind turbine, a wind measurement system, and a nacelle position detection system; the yaw optimization control system includes the yaw optimization control system as described in the first aspect of the present invention;

[0014] The main controller of the wind turbine is respectively connected to the wind measurement system and the nacelle position detection system, and generates a yaw alignment command according to the wind direction data detected by the wind measurement system and the position data detected by the nacelle position detection system;

[0015] The yaw optimization control system performs information interaction with the main controller of the wind turbine through the information interaction interface module, receives the yaw alignment command sent by the main controller of the wind turbine, and feeds back the working status of the yaw control module.

[0016] According to the third aspect of the present invention, there is provided a yaw control method for a yaw control system as described in the second aspect of the present invention, including the steps of:

[0017] In the yaw stop stage, relevant information is obtained from the main controller of the wind turbine, and the enabling of the yaw hot standby state control is executed;

[0018] In the yaw operation stage, in the enabled yaw hot standby state, after receiving the yaw action instruction, enter the yaw operation stage;

[0019] In the yaw fault shutdown stage, when the wind turbine is in the yaw fault shutdown state, coordinately control the yaw motor to decelerate evenly, and at the same time coordinately control the yaw hydraulic solenoid valve to build up the yaw brake pressure to the maximum pressure value.

[0020] Further, the yaw stop stage is the state when the yaw motor of the wind turbine generator set is stationary; the yaw operation stage is the stage when the yaw motor of the wind turbine generator set is operating; the yaw fault shutdown stage is the shutdown process of the yaw system.

[0021] Further, the execution of the enabling of the yaw hot standby state control includes:

[0022] Open the yaw motor brake, allocate forward and reverse drive commands to the motion control unit, coordinately control the yaw motor to evenly distribute the forward and reverse drive speeds, so that the yaw pinion of the yaw drive mechanism slowly meshes with the large teeth of the yaw slewing bearing for gear clearance compensation;

[0023] Adjust the forward and reverse balance torques output by the yaw motor respectively;

[0024] Coordinately control the yaw hydraulic valve to release the yaw brake pressure to the residual pressure value, and at the same time rely on the balance torque output by the yaw motor to keep the nacelle yaw position unchanged.

[0025] Further, the optimized yaw operation control in the yaw hot standby state includes:

[0026] According to the yaw action instruction, control some yaw motors to gradually load the driving torque, some yaw motors adjust the reverse damping force, and drive the yaw motors to accelerate gently to the rated speed of the yaw motor;

[0027] When receiving the yaw stop action command, control the yaw motor to reduce the speed until the yaw speed is zero, and at the same time adjust the torque of the yaw motor to the yaw hot standby state.

[0028] Further, when the wind turbine is in the yaw fault shutdown state, it further includes:

[0029] When the yaw system shutdown is completed and the yaw motor speed reaches the safe value, coordinately control the yaw motor torque to drop to zero and complete the electromagnetic brake holding of the yaw motor.

[0030] Further, the yaw fault includes safety chain system fault and over-twisted cable protection fault.

[0031] In summary, the embodiment of the present invention provides a yaw optimization control system and its control method for a wind turbine generator set. The system includes a yaw control module, an information interaction interface module, a yaw brake module, and a yaw drive module, which are used to optimize the control of the components related to the yaw mechanism of the existing wind turbine generator set. The technical solution of the embodiment of the present invention can achieve soft start and stop control of the yaw motor, avoid the current and mechanical impacts on the yaw motor during the start and stop processes; achieve gentle meshing of the gear clearance between the large yaw gear and the driving small gear before yaw start, avoid mechanical impacts caused by gear clearance during the start process; achieve dynamic control of the braking force of the yaw braking system during yaw, reduce mechanical wear and noise; at the same time, it also realizes dynamic real-time control of the motor output torque during yaw to complete accurate real-time wind position control, improve the maximum wind energy capture ability of the wind turbine, reduce mechanical friction, and reduce the mechanical faults of the unit, thereby improving the stability of the yaw system of the wind turbine, increasing the availability and power generation of the wind turbine generator set, and improving the overall efficiency of the optimized unit. Description of the Drawings

[0032] Figure 1 is the block diagram of the yaw system of the prior art wind turbine generator set;

[0033] Figure 2 is the block diagram of the yaw optimization control system of the embodiment of the present invention. Detailed Embodiments

[0034] To make the purpose, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in combination with specific embodiments and with reference to the accompanying drawings. It should be understood that these descriptions are exemplary and are not intended to limit the scope of the present invention. In addition, in the following description, the descriptions of well-known structures and technologies are omitted to avoid unnecessarily confusing the concepts of the present invention.

[0035] The yaw mechanical structure of a large horizontal-axis wind turbine mainly consists of a yaw braking mechanism and a yaw driving mechanism. A brake disc is installed on the outer gear ring of the yaw slewing bearing at the bottom of the wind turbine nacelle, and is fastened to the top flange of the tower with high-strength bolts at the same time as the outer gear ring. The inner ring of the yaw slewing bearing is connected to the main frame of the nacelle, and several sets of yaw brakes are distributed and installed at the connection. By controlling the hydraulic pressure of the brake calipers of the brakes, the friction pads of the yaw brakes are tightened or loosened against the yaw brake disc, thus forming the yaw braking mechanism of the wind turbine. The yaw driving mechanism includes 4 speed reducers evenly distributed in the nacelle. The pinions on the speed reducers mesh with the large gears of the outer gear ring of the yaw slewing bearing. By controlling the meshing drive of the asynchronous motor to drive the speed reducer, the wind turbine is pushed to complete yaw and wind alignment rotation.

[0036] Regarding the control system research on the yaw mechanical structure of currently operating wind turbines, phased coordinated control is carried out on the yaw braking mechanism and the yaw driving mechanism during the yaw process.

[0037] Yaw stop stage: The control system keeps the yaw motor in a stationary state. By controlling the solenoid valve of the yaw hydraulic circuit, the hydraulic pressure of the brake calipers of the yaw brakes reaches the designed maximum value, and the friction pads of the yaw brakes are kept tightened against the yaw brake disc, so as to maintain the yaw stop state of the wind turbine. The braking state is maintained by frictional resistance, and at the same time, the maintenance brake system of the yaw motor is utilized.

[0038] Yaw running stage: The control system controls the solenoid valve of the yaw hydraulic circuit to maintain the hydraulic pressure of the brake calipers of the yaw brakes at the yaw damping residual pressure value, and keeps a certain frictional force between the friction pads of the yaw brakes and the yaw brake disc to form a mechanical damping force to ensure the yaw process. Thus, it blocks the thrust in the horizontal direction on the unit to ensure stable yaw of the nacelle. The control system also controls the start of the yaw motor to work, and drives the yaw and wind alignment of the wind turbine through the yaw driving mechanism.

[0039] Since yaw motors are mostly asynchronous motors, there are currently three main control schemes for the start and stop control of yaw motors in the industry. Method 1: Directly start and stop the motor through a relay; Method 2: Use a soft starter to control the start and stop of the yaw motor; Method 3: Use a frequency converter to adjust and control the start and stop of the motor. These three different motor start and stop methods have the same system control scheme for the yaw mechanism.

[0040] In the current yaw system control scheme, during the yaw stop phase, the yaw system is in a mechanical braking state, and the operating state of the unit is not considered. When the unit is operating under the conditions above the cut-in wind speed and below the rated wind speed, to achieve optimal power control, the wind turbine needs to accurately align with the wind to maximize the capture and utilization of wind energy. After the wind direction changes, the yaw alignment needs to complete the transition from yaw stop to yaw operation. The mechanical action execution of the yaw mechanism takes a certain amount of time. Moreover, to avoid frequent actions of the yaw mechanism, the control system amplifies the yaw alignment angle of the nacelle. As a result, the wind turbine cannot accurately align with the wind in real time, resulting in the loss of some wind energy capture.

[0041] During the yaw operation phase, the wind exerts a thrust on the wind turbine in the yaw direction. To avoid excessive vibration of the wind turbine during yaw, a certain damping torque is required in the yaw mechanism. The conventional scheme simply relies on the mechanical friction damping force of the yaw braking mechanism. That is, by controlling the yaw brake caliper to retain a certain residual pressure, a certain dynamic friction force is formed between the yaw brake friction plate and the yaw brake disc, so as to achieve the damping torque during the yaw process of the unit. This traditional design scheme causes mechanical wear and noise of the yaw brake. Even after the friction surfaces of the brake disc and the brake are contaminated, the mechanical friction coefficient changes, resulting in unstable yaw damping torque and causing the vibration of the unit.

[0042] Among the three mentioned start-stop control methods of the yaw motor, there are certain defects: Method 1, directly starting and stopping the yaw motor by the contactor will cause large current and mechanical shocks to the motor, resulting in electrical damage or mechanical damage to the yaw motor, and even causing fluctuations in the power quality of the system; Method 2, using a soft starter to start and stop the motor to limit the starting current and initial voltage of the motor. However, during the yaw start-up process, due to the large mass of the unit, the soft starter is a heavy overload start, which is likely to cause too long motor start-up time, resulting in motor overheating or stalling, and cannot avoid mechanical shocks; Method 3, using a frequency converter to control the start and stop of the motor, using frequency conversion technology to achieve motor start-stop control, but it cannot accurately control the follow-up changes of torque and position during operation, and cannot avoid mechanical and electrical shocks.

[0043] The nacelle will be subjected to the thrust from the wind in the yaw direction. To ensure the stability of the wind turbine during the yaw process, the yaw system needs to apply a certain yaw pressure to maintain a certain pressure between the yaw brake and the yaw brake disc, and use mechanical friction to provide a certain mechanical damping force for the nacelle yaw process. As a result, the sliding friction between the yaw brake disc and the yaw brake during the yaw process causes serious mechanical wear, vibration and noise problems. Especially during the long-term operation of the wind turbine, common faults such as brake oil leakage, severe wear of the brake caliper friction pads, pollution or scratches on the brake disc, noise and vibration during the yaw process occur. At the same time, the start-stop control of the yaw motor causes a large degree of mechanical impact between the yaw reducer gear and the large gear of the yaw bearing. The yaw control system's start-stop control of the yaw motor belongs to a rough start-stop control. For the meshing clearance impact existing between the gears of the yaw system, there is a lack of precise dynamic adjustment control algorithms and execution units, and it does not even have the ability to regulate the yaw damping torque. As the operation time of the wind turbine increases, the problem of yaw failure in the units with traditional yaw systems and yaw control system solutions becomes increasingly prominent, and the operation and maintenance costs of the wind turbine also increase significantly.

[0044] The technical solution of the present invention will be described in detail below with reference to the accompanying drawings. According to an embodiment of the present invention, a yaw optimization control system for a wind turbine is provided. The system includes a yaw control module, an information interaction interface module, a yaw braking module and a yaw drive module. The yaw control module is used to receive the yaw command from the original unit control system and coordinate the control of the yaw braking mechanism and the yaw drive mechanism to complete the yaw alignment function of the wind turbine. Figure 1 shows the block diagram of the yaw system of the prior art wind turbine, including a main controller and a yaw braking system, a yaw drive system, a wind measurement system and a nacelle position detection system connected to the main controller. The control of each mechanical structure is directly coordinated and controlled by the main controller.

[0045] The yaw optimization control system provided by the embodiment of the present invention realizes the coordinated control of each mechanical structure of the yaw system of the wind turbine, receives the information of the main controller, optimizes the control of each mechanical structure of the yaw system, and is used to realize the flexible start-stop during the yaw process of the wind turbine and improve the alignment accuracy. Figure 2 shows the block diagram of the yaw optimization control system of the embodiment of the present invention, as Figure 2 shown,

[0046] The output of the yaw control module is connected to the yaw brake module and the yaw drive module. The yaw control module is used to execute the yaw alignment command, coordinate the actions of the yaw brake module, and issue motion control instructions to the yaw drive module to complete the motion control of the yaw motor and achieve yaw alignment. This yaw control module is responsible for executing the yaw alignment command of the original fan control system, coordinating the actions of the yaw brake system, issuing motion control instructions to the motion control unit, completing the motion control of the yaw motor, and achieving yaw alignment.

[0047] The information interaction interface module is connected to the yaw control module, and is used to transmit the yaw alignment command to the yaw control module and feedback the working state of the yaw control module. This information interaction interface module is used to complete the transmission of the yaw command of the original fan control system and feedback the working state of the yaw control module. The information interaction content includes but is not limited to data volumes such as DI, DO, AI, and AO.

[0048] The yaw brake module includes a yaw hydraulic valve and a yaw brake. The yaw brake module controls the action state of the yaw brake module by changing the state of the yaw hydraulic valve and adjusting the hydraulic pressure of the brake caliper of the yaw brake. In the embodiment of the present invention, the yaw brake system retains the structure of the yaw brake system of the unit, but the yaw hydraulic valve is transformed from the original fan control system and connected to the yaw control module to execute relevant control methods and control logic commands, so that the yaw brake can meet the control logic requirements.

[0049] The yaw drive module includes a motion control unit, a yaw motor, and a motor encoder; the motion control unit executes the motion control command, dynamically adjusts the torque and speed output by the yaw motor, and feedbacks the yaw motor encoder information to the yaw control module. In the embodiment of the present invention, a yaw motor encoder is added to the yaw drive mechanism of the original unit, and at the same time, the yaw motor control circuit of the original system is completely taken over. The motion control unit is directly responsible for driving the yaw motor to work, and drives the yaw motor to work by executing the speed and torque commands of the yaw control unit through the motion control unit. The motion control unit is responsible for accurately executing the motion control command, dynamically adjusting the torque and speed output by the yaw motor, and feedbacking the yaw motor encoder information to the yaw control unit.

[0050] According to an embodiment of the present invention, a yaw control system for a wind turbine generator is further provided, including a yaw optimization control system, a fan main controller, a wind measurement system, and a nacelle position detection system; the yaw optimization control system is, for example, the above-mentioned yaw optimization control system.

[0051] The fan main controller is respectively connected to the wind measurement system and the nacelle position detection system, and generates a yaw alignment command according to the wind direction data detected by the wind measurement system and the position data detected by the nacelle position detection system;

[0052] The yaw optimization control system exchanges information with the main controller of the wind turbine through the information interaction interface module, receives the yaw alignment command sent by the main controller of the wind turbine, and feeds back the working state of the yaw control module.

[0053] According to an embodiment of the present invention, there is also provided a yaw control method, for example, used in the above yaw control system, including the following steps:

[0054] Step 1: Yaw hot standby control.

[0055] In the yaw stop stage, relevant information is obtained from the main controller of the wind turbine, and the yaw hot standby state control is enabled. After the initialization of the original wind turbine control system is completed and the system safety chain signal is normal, the yaw control module obtains relevant information through the information interaction interface module and executes the yaw enabled hot standby state. The relevant information includes safety chain status, nacelle position, yaw stop command and other information. The yaw control module first opens the yaw motor brake, distributes forward and reverse drive commands to the motion control unit, coordinates the forward and reverse drive speeds of the four yaw motors evenly, so that the yaw pinion of the yaw drive mechanism slowly and gently meshes with the large gear of the yaw slewing bearing. After the gear clearance is slowly compensated, the motion control unit adjusts the forward and reverse balance torques output by the four motors respectively. The yaw control module coordinates and controls the yaw hydraulic solenoid valve to release the yaw brake pressure to the residual pressure value, and at the same time relies on the motor output balance torque to keep the nacelle yaw position unchanged. Thus, the yaw braking module and the yaw drive module maintain the yaw enabled hot standby state. When the original control system issues a yaw command, the yaw braking system does not need to perform mechanical actions frequently, and the change of the driving torque of the yaw motor by the motion control unit can complete the transition from the yaw stop state to the yaw running state. This step controls the yaw braking system and the yaw drive system to keep the yaw position of the wind turbine generator from moving during the yaw stop stage, and at the same time makes the yaw mechanism in the "yaw hot standby" state. This step of this embodiment can make the yaw mechanism of the wind turbine generator in the hot standby state during the yaw stop stage, use the yaw motor to provide the braking force to keep still, and meet the requirement that the yaw position of the wind turbine generator does not move during the yaw stop stage. At the same time, when the yaw mechanism enters the "yaw hot standby" state in this step, the yaw drive pinion and the large gear of the yaw slewing bearing complete a slow and gentle meshing process, avoiding the meshing impact generated by the yaw start, and at the same time the yaw motor also completes a flexible start to avoid mechanical and electrical impacts.

[0056] Step 2: Optimize the yaw operation control in the yaw hot standby state enabled in the yaw stop stage of Step 1.

[0057] The optimized yaw operation control in the yaw hot standby state receives yaw action instructions, such as left yaw command or right yaw command, and enters the yaw operation stage. According to the left and right yaw commands of the original wind turbine control system, the yaw control module coordinates the motion control unit to control the two yaw motors in the yaw direction to gradually load the torque, and the other two yaw motors adjust the reverse damping force, and drive the yaw motor to accelerate smoothly to the rated speed of the yaw motor. The horizontal wind load borne by the wind turbine during the yaw process is dynamically changing. In order to ensure that the nacelle yaws against the wind at a uniform speed, the yaw control module coordinates the motion control unit to dynamically adjust the output torque of the four yaw motors, so that the yaw drive mechanism is dynamically balanced during the yaw process, avoiding the unit from swaying and vibration during the yaw process. When the original wind turbine control system issues a yaw stop action command, the yaw control unit adjusts the motion control unit to drive the yaw motor to slowly reduce the speed until the yaw speed is zero, and at the same time adjusts the torque of the yaw motor to the yaw system hot standby state. This step enables the yaw mechanism of the wind turbine generator set to realize three operation control states of slow acceleration, smooth uniform speed and balanced deceleration by coordinating and controlling the speed and output torque of the yaw motor through the motion control unit during the yaw operation stage. Controlling the yaw motor realizes a smooth acceleration start with a stable torque, realizes the flexible start of the yaw drive system, avoids the sudden change of torque and speed of the yaw drive system in the conventional scheme, and avoids mechanical impact damage to the yaw motor and reducer.

[0058] Step 3: Yaw failure shutdown stage

[0059] When the fan is in the yaw fault shutdown state, the yaw motor is coordinated and controlled to decelerate evenly, and the yaw hydraulic solenoid valve is coordinated and controlled to establish the yaw brake pressure to the maximum pressure value. In the yaw stop stage, the fan operation state is obtained from the fan main controller, and the yaw fault shutdown state includes but is not limited to the safety chain system failure or the over-torsion cable protection failure. The yaw control module coordinates and controls the yaw motor to decelerate evenly. At the same time, the yaw control module coordinates and controls the yaw hydraulic solenoid valve to establish the yaw brake pressure to the maximum pressure value. After the yaw system is shut down and the yaw motor speed reaches the safe value, the yaw control module coordinates and controls the yaw motor torque to zero and completes the motor electromagnetic brake. In this step of the present embodiment, after the wind direction changes, the yaw needs to complete the transition from yaw stop to yaw operation. The mechanical action of the yaw mechanism takes a certain amount of time to execute. Using step two, the unit operation state avoids frequent actions of the yaw mechanism, and the control system amplifies the yaw wind angle of the cabin. At the same time, step three ensures the safety of the unit at the moment of yaw system failure.

[0060] In summary, the present invention relates to a yaw optimization control system and a control method thereof for a wind turbine generator. The system includes a yaw control module, an information interaction interface module, a yaw brake module, and a yaw drive module, which are used to optimize the control of the components related to the yaw mechanism of an existing wind turbine generator. The technical solution of the embodiment of the present invention utilizes a yaw optimization control system composed of a yaw control module, an information interaction interface module, etc., to receive commands from the main controller and coordinate the control of the yaw brake and the yaw drive system to complete the yaw alignment of the wind turbine generator; the control method of the embodiment of the present invention proposes an optimization control method for the yaw system hot standby state of the yaw mechanism during the yaw stop stage of a large wind turbine generator; utilizes the yaw control module to coordinate the control of the yaw brake and the optimized stationary control state of the yaw drive motor to form a yaw enable hot standby state for the yaw brake system and the yaw drive system; when the yaw mechanism enters the "yaw hot standby" state, the yaw drive pinion and the yaw slewing bearing gear complete a slow and gentle meshing process, avoiding the meshing impact generated during yaw startup, and at the same time the yaw motor also completes a flexible startup to avoid mechanical and electrical impacts; enables the yaw mechanism of the wind turbine generator to achieve three operating control states of slow acceleration operation, smooth and uniform operation, and balanced deceleration operation of the yaw motor through the coordinated control of the speed and output torque of the yaw motor by the motion control unit during the yaw operation stage; when the yaw mechanism of the wind turbine generator enters the yaw stage, it fully cooperates with the operating state of the unit, reduces the operating state of the unit to avoid frequent actions of the yaw mechanism, and at the same time ensures the safety of the unit at the moment of yaw system failure.

[0061] It should be understood that the above specific embodiments of the present invention are only used for exemplary illustration or explanation of the principles of the present invention, and do not constitute a limitation to the present invention. Therefore, any modifications, equivalent replacements, improvements, etc. made without departing from the spirit and scope of the present invention shall be included within the protection scope of the present invention. In addition, the appended claims of the present invention are intended to cover all changes and modifications that fall within the scope and boundaries of the appended claims, or equivalent forms of such scope and boundaries.

Claims

1. A yaw control method for a yaw control system of a wind turbine generator, characterized in that, The yaw control system of the wind turbine generator set includes a yaw optimization control system, a main wind turbine controller, a wind measurement system, and a nacelle position detection system; the yaw optimization control system includes a yaw control module, an information interaction interface module, a yaw brake module, and a yaw drive module; The output of the yaw control module is connected to the yaw brake module and the yaw drive module. The yaw control module is used to execute the yaw alignment command, coordinate the actions of the yaw brake module, and issue motion control instructions to the yaw drive module to complete the motion control of the yaw motor and achieve yaw alignment; the information interaction interface module is connected to the yaw control module, used to transmit the yaw alignment command to the yaw control module and feedback the working state of the yaw control module; The yaw drive module includes a motion control unit, a yaw motor, and a motor encoder; the motion control unit executes the motion control command, dynamically adjusts the torque and speed output by the yaw motor, and feeds back the yaw motor encoder information to the yaw control module; The control method includes the steps: In the yaw stop stage, obtain relevant information from the main wind turbine controller and execute the enabling of the yaw hot standby state control; In the yaw running stage, in the enabled yaw hot standby state, after receiving the yaw action command, enter the yaw running stage; In the yaw fault shutdown stage, when the wind turbine is in the yaw fault shutdown state, coordinate and control the yaw motor to decelerate evenly, and at the same time coordinate and control the yaw hydraulic solenoid valve to build the yaw brake pressure to the maximum pressure value.

2. The method according to claim 1, wherein The yaw brake module includes a yaw hydraulic valve and a yaw brake; The yaw brake module adjusts the hydraulic pressure of the yaw brake caliper by changing the state of the yaw hydraulic valve to control the action state of the yaw brake module.

3. The method according to claim 1, characterized in that, The yaw stop stage is the state when the yaw motor of the wind turbine generator set is stationary; the yaw running stage is the stage when the yaw motor of the wind turbine generator set is running; the yaw fault shutdown stage is the yaw system shutdown process.

4. The method according to claim 3, characterized in that, Executing the enabling of the yaw hot standby state control includes: Open the yaw motor brake, allocate forward and reverse drive commands to the motion control unit, coordinate the yaw motor to evenly distribute the forward and reverse drive speeds, and make the yaw pinion of the yaw drive mechanism slowly engage with the large teeth of the yaw slewing bearing for gear clearance compensation; Adjust the forward and reverse balance torques output by the yaw motor respectively; Coordinate and control the yaw hydraulic valve to release the yaw brake pressure to the residual pressure value, and at the same time rely on the balance torque output by the yaw motor to keep the nacelle yaw position unchanged.

5. The method according to claim 3, characterized in that, The optimized yaw running control in the yaw hot standby state includes: According to the yaw action command, control some yaw motors to gradually load the driving torque, some yaw motors adjust the reverse damping force, and drive the yaw motors to accelerate smoothly to the rated speed of the yaw motor; When receiving the yaw stop action command, control the yaw motor to reduce the speed until the yaw speed is zero, and at the same time adjust the torque of the yaw motor to the yaw hot standby state.

6. The method according to claim 4, wherein When the wind turbine is in the yaw fault shutdown state, it also includes: When the yaw system shutdown is completed and the yaw motor speed reaches the safe value, coordinate and control the yaw motor torque to drop to zero and complete the electromagnetic brake hold of the yaw motor.

7. The method according to claim 6, wherein The yaw fault includes safety chain system fault and over-twisted cable protection fault.

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