The performance of the wind yaw system is related to the following factors:
1、 Factors related to mechanical structure
yaw bearing
The quality and performance of yaw bearings are crucial. Its load-bearing capacity determines whether it can support the weight of the entire cabin and impeller. For example, for large wind turbines, the weight of the nacelle and impeller can reach tens or even hundreds of tons, and high-quality yaw bearings can withstand huge radial and axial loads.
The friction coefficient of bearings is also important. Bearings with low friction coefficients can reduce resistance during yaw, making yaw movements more flexible and smooth. Bearings using special lubrication methods and materials (such as composite materials with self-lubricating function) can effectively reduce friction and improve the efficiency of the yaw system.
Drive device (motor and gearbox)
Motor performance: The torque output capability of the motor directly affects the yaw speed and driving force. Sufficient torque can ensure accurate yaw of the cabin even under harsh conditions such as strong winds. For example, at high wind speeds, due to the significant force exerted by the wind on the impeller, the motor needs to provide strong torque to overcome resistance and achieve yaw. At the same time, the precision of motor speed control is also important. Accurate speed control can make the yaw process smoother and avoid yaw errors caused by too fast or too slow speed.
Gearbox transmission ratio and efficiency: The gearbox is used to convert the high-speed low torque output of the motor into a low-speed high torque output suitable for yaw. The appropriate transmission ratio can adjust the torque and speed according to the characteristics of the motor and the actual requirements of the yaw system. Moreover, the transmission efficiency of the gearbox affects energy loss, and an efficient gearbox can reduce energy waste and improve the overall performance of the yaw system. For example, using high-precision planetary gearboxes can achieve larger transmission ratios and higher transmission efficiency.
brake rigging
The braking device is used to lock the cabin position after the yaw is in place, preventing the cabin from deviating from the set direction under wind force. The braking torque of the braking device should be moderate. Excessive braking torque may cause damage to mechanical components, while insufficient torque may not effectively secure the engine compartment. For example, in strong wind environments, the braking device must be able to withstand the enormous torque of the wind on the cabin to prevent accidental yaw of the cabin. The response speed is also important, and a fast response braking device can quickly brake upon receiving a stop command, improving the safety of the yaw system.
Structural stiffness of engine room and tower
The structural stiffness of the engine room and tower affects the stability of the yaw system. Adequate stiffness can prevent excessive shaking or deformation of the cabin during yaw. For example, when the yaw motor drives the engine room to rotate, if the structural stiffness of the engine room is insufficient, it may cause engine room vibration, which not only affects yaw accuracy, but also may damage internal equipment. The stiffness of the tower is also important, as it must be able to withstand the reaction force generated by the yaw of the engine room and maintain stability under external forces such as wind loads.
2、 Control system related factors
Accuracy of control algorithm
Wind direction detection and tracking algorithm: Accurate wind direction detection is a prerequisite for the normal operation of the yaw system. After obtaining wind direction information through sensors such as anemometers, the control algorithm should be able to quickly and accurately calculate the angle at which the cabin needs to yaw. For example, using advanced vector control algorithms can adjust the yaw direction of the cabin in real time according to changes in wind direction, and compensate for errors in wind direction sensors to improve yaw accuracy.
Yaw speed control algorithm: Reasonable yaw speed control can make the yaw process smooth and efficient. The control algorithm should consider factors such as motor performance and load conditions to determine the optimal yaw speed. For example, when the wind speed is low, the yaw rate can be appropriately increased to improve wind efficiency; When the wind speed is high, the yaw rate should be reduced to avoid the impact force and vibration caused by excessive yaw.
Accuracy and reliability of sensors
Wind direction sensor: The accuracy of the wind direction sensor directly determines the accuracy of the yaw system to the wind. High precision wind direction sensors can more accurately detect changes in wind direction, and their resolution and measurement error are important performance indicators. For example, high-resolution wind direction sensors can detect small changes in wind direction, allowing the yaw system to adjust the direction of the cabin in a timely manner and maintain the impeller’s alignment with the wind.
Position sensor: The position sensor is used to monitor the yaw angle of the cabin. Its accuracy affects the positioning accuracy of the yaw system. For example, using high-precision encoders as position sensors can accurately measure the yaw angle of the cabin and provide feedback to the control system, achieving closed-loop control and improving yaw accuracy.
Stability of communication system
Information communication is required between the yaw control system and other control systems of the wind turbine (such as the main control system). A stable communication system can ensure accurate transmission of yaw commands and timely reception of feedback information. For example, using fiber optic communication or strong anti-interference industrial Ethernet communication methods can avoid the influence of electromagnetic interference and other factors on communication, enabling the yaw system to respond to the instructions of the main control system in a timely manner, such as performing yaw operations according to different power generation modes and wind speed conditions.
3、 External environmental factors
Characteristics of changes in wind speed and direction
The frequency and amplitude of changes in wind speed and direction have a significant impact on the performance of the yaw system. In an environment with frequent changes in wind direction, the yaw system needs to perform frequent yaw operations. For example, in mountainous or coastal areas, wind direction may rapidly change due to the influence of terrain and ocean airflow, which requires yaw systems to have fast response capabilities and high wind accuracy.
The high wind speed environment poses greater challenges to the yaw system. Under strong wind conditions, the force exerted by the wind on the engine compartment is enormous. The yaw system must not only achieve accurate yaw, but also ensure the safety and stability of the engine compartment. For example, when the wind speed exceeds the rated wind speed, the yaw system may need to deflect the nacelle to a safe position, such as the feathering position, according to the control strategy of the wind turbine to avoid equipment damage.
Climate conditions such as temperature and humidity
Temperature changes can affect the performance of mechanical components in the yaw system. For example, in low-temperature environments, the viscosity of lubricating oil increases, leading to increased friction between the yaw bearing and gearbox, which affects the flexibility of yaw. In high temperature environments, the performance of electrical equipment such as motors may decrease, and heat dissipation issues need to be considered to prevent equipment from overheating and damage.
Humidity has a corrosive effect on metal components. The metal structure of the yaw system (such as yaw bearings, gearbox housing, etc.) that is exposed to high humidity for a long time may rust, reducing its mechanical performance and service life. Therefore, in areas with high humidity, appropriate anti-corrosion measures need to be taken for the yaw system, such as using special coatings or sealing structures.