Methods and systems for wind turbine blade forward and reverse rotation adjustment and protection in environments with high wind speed and sandstorms.

Abstract

This invention discloses a method and system for adjusting and protecting wind turbine blades in environments with high wind speed and sandstorms. The system includes a power supply, a PLC control system, wind turbine blades, a touchscreen, a stepper motor, a closed-loop stepper driver, an integrated vibration transmitter, and a wind speed sensor. The wind speed sensor monitors wind speed, and the integrated vibration transmitter monitors the vibration of the wind turbine blades. Signals from the wind speed sensor and the integrated vibration transmitter are transmitted and connected to the control system. Similarly, the closed-loop stepper driver, which drives the stepper motor driving the wind turbine blades, also transmits and connects to the control system. The control system sends pulses or control signals to control the closed-loop stepper driver, which in turn drives the stepper motor to adjust its forward and reverse rotation in windy and sandy environments. This invention can determine the environmental state of the wind turbine by detecting wind speed and sandstorms, thereby achieving the purpose of protecting the wind turbine blades by adjusting the stepper motor's reverse rotation in sandy environments.

Description

Technical Field

[0001] This invention belongs to the field of wind turbine blade protection technology, and particularly relates to a method and system for adjusting and protecting wind turbine blades in the forward and reverse rotation under conditions of high wind speed and sandstorms. Background Technology

[0002] The utilization cost of wind turbine blades accounts for approximately 20%-30% of the total utilization cost of the entire wind power system. The construction cost of wind farm equipment can generally be divided into wind turbine construction costs, installation costs, building construction costs, and other expenses. Taking a 50MW wind farm as an example, about 70% of the construction cost comes from wind turbine installation costs; of the wind turbine installation costs, 94% comes from the wind turbine equipment itself; and of the wind turbine installation costs, 80% comes from the construction cost of the wind turbine generator set, while 17% comes from the construction cost of the wind turbine tower. Based on this calculation, the construction cost of the entire wind turbine generator set accounts for approximately 51% of the total power investment of the entire wind farm, and the cost of the tower and turbine unit accounts for approximately 11% of the total wind power investment. Both of these equipment purchase and maintenance costs will be the main input costs in the early stages of wind farm construction. The design of specialized wind turbine blades needs to simultaneously possess basic characteristics such as large blade size, complex shape, high precision technical requirements, uniform distribution of quality characteristics, and good high-temperature weather resistance. Currently, the annual market size for wind turbine blades is approximately 15-20 billion yuan. When a blade fails, especially when a single blade breaks, the balance shafts of the three blades are automatically interrupted during rotation, causing the generator set to experience instantaneous and severe vibration. If the generator set's protection system fails to activate or the control unit's protection equipment delays stopping, this will not only cause severe mechanical damage to the internal bearing system and tower of the entire generator set, but may also directly lead to serious damage to the entire generator set. Moreover, before the generator set begins braking, the broken blade may soon collide with two adjacent blades or the tower shaft, increasing the potential economic losses from the accident. After a wind turbine experiences a voltage failure and power outage, the wind farm must immediately shut down for maintenance and must continue to wait for optimal operating conditions with only light winds or no wind. This results in high electromechanical maintenance costs and the loss of a valuable opportunity for power generation due to "wind curtailment." A single wind turbine accident with severely damaged blades resulted in direct and indirect socio-economic losses of nearly one million yuan. An analysis of the current status of blade maintenance and daily management work of various types of wind power operating companies reveals a lack of awareness of the importance of daily maintenance of damaged blades, lax quality control in the daily blade maintenance process, and insufficient investment in daily maintenance management. As a result, the safety hazards of damaged blades have been increasing rapidly over the years during actual wind power operation, and they are likely to directly lead to various wind turbine accidents at any time, seriously affecting the socio-economic benefits of wind power companies.

[0003] The impeller shaft of a wind turbine is responsible for automatically converting internal wind energy into various forms of mechanical kinetic energy. It consists of wind turbine blades, a hub, and other components. The blades convert the various kinetic energies of the air into various mechanical kinetic energies that pass through the blades and the impeller shaft, which are then converted into electrical energy by a generator. The size and shape of the blades directly determine the efficiency of energy flow conversion, as well as the operating power and performance of the wind turbine unit. Therefore, large wind turbine drive blades have always held a crucial core technological position in the design of large wind turbine units. During wind turbine operation, the blades are prone to breakage, surface cracks, and dents due to the wind pressure caused by excessive wind speeds and the impact of excessive sandstorms. Protecting the blades in environments with excessive wind speeds or sandstorms is therefore of paramount importance. Summary of the Invention

[0004] Purpose of the invention: In order to overcome the shortcomings of the existing technology, the present invention provides a method and system for adjusting and protecting the wind turbine blades in the forward and reverse rotation under conditions of excessive wind speed and sandstorm. It can determine the environmental state of the wind turbine by detecting wind speed and sandstorm, thereby achieving the protection of the wind turbine blades by adjusting the reverse rotation of the stepper motor in strong wind and sandstorm and strong wind and weak sandstorm environments.

[0005] Technical Solution: To achieve the above objectives, the present invention provides a method for adjusting and protecting the forward and reverse rotation of wind turbine blades in windy and sandy environments. This method uses a wind speed sensor to monitor wind speed and an integrated vibration transmitter to monitor the vibration of the wind turbine blades. The signals from the wind speed sensor and the integrated vibration transmitter are transmitted and connected to a control system. The closed-loop stepper driver that drives the stepper motor of the wind turbine blades also transmits and connects to the control system. The control system sends pulses or control signals to control the closed-loop stepper driver, which in turn drives the stepper motor to adjust its forward and reverse rotation in windy and sandy environments.

[0006] Furthermore, the wind speed includes a weak wind speed range (v1, v2) and a strong wind speed range (v3, v4); the vibration includes a weak vibration range (f1, f2) and a strong vibration range (f3, f4); and the fan blades, when driven in reverse by a stepper motor, have four settings: no adjustment limit, fine adjustment limit, obvious adjustment limit, and direct adjustment limit.

[0007] When the wind speed is in the weak wind speed range (v1, v2) and the vibration is in the weak vibration range (f1, f2), it indicates a weak wind and sand environment. There is no need to adjust the stepper motor to reverse, and it belongs to the category of no need to adjust the limit gear.

[0008] When the wind speed is in the weak wind speed range (v1, v2) and the vibration is in the strong vibration range (f3, f4), it indicates a weak wind and strong sand environment. The micro-adjustment stepper motor reverses, which is the micro-adjustment limit gear.

[0009] When the wind speed is in the strong wind range (v3, v4) and the vibration is in the strong vibration range (f3, f4), it indicates a strong wind and sand environment. The stepper motor should be reversed, which is a clear adjustment limit setting.

[0010] When the wind speed is in the strong wind range (v3, v4) and the vibration is in the weak vibration range (f1, f2), it indicates a strong wind and weak sand environment. Directly adjusting the stepper motor to reverse is a direct adjustment of the limit gear.

[0011] Furthermore, the control system is a PLC control system capable of generating high-frequency pulses. After the PLC control system is powered on, when X1 is turned on, Y0 continuously outputs 800 pulses at an output frequency of 1500Hz.

[0012] Furthermore, when adjusting the stepper motor to reverse in a strong wind and weak sand environment, the PLC control system sends a pulse, M14 is turned on, and when D0>40, M22 is turned on. After M23 is turned on, the stepper motor reverses, T0 is turned on for 3 seconds, and after 3 seconds T0 is turned off, the stepper motor stops moving.

[0013] Furthermore, when adjusting the stepper motor to reverse in a strong wind and sand environment, the PLC control system sends a pulse. When D1>50, M32 is turned on. After M33 is turned on, the stepper motor reverses. T1 is turned on and timed for 3 seconds. After 3 seconds, T1 is turned off and the stepper motor stops moving.

[0014] A wind turbine blade forward and reverse rotation adjustment and protection system for wind turbines operating under conditions of high wind speed and sandstorms includes a power supply, a PLC control system, wind turbine blades, a touch screen, a stepper motor, a closed-loop stepper driver, an integrated vibration transmitter, and a wind speed sensor. The power supply provides power to the PLC control system, the touch screen, the stepper motor, the closed-loop stepper driver, the integrated vibration transmitter, and the wind speed sensor. The PLC control system controls the stepper motor through the closed-loop stepper driver. The touch screen is connected to the PLC control system. The integrated vibration transmitter and the wind speed sensor are respectively connected to the PLC control system for signal transmission.

[0015] Furthermore, the integrated vibration transmitter is installed at the bearing housing of the fan blade or the bearing housing of the stepper motor.

[0016] Furthermore, the wind turbine blades include the rotor blades of a horizontal axis wind turbine generator set.

[0017] Beneficial effects: This invention, through PLC system design, uses an integrated vibration transmitter and wind speed sensor to simulate wind and sand conditions and wind speed, respectively. When the stepper motor reverses, the analog signal is converted into a digital signal by the A / D module and input into the PLC. After a series of program runs, the PLC drives the stepper motor to reverse through the SM808D stepper driver. Therefore, by detecting wind speed and wind and sand, the environmental state of the wind turbine can be determined. This allows for the protection of the wind turbine blades by adjusting the stepper motor to reverse in windy and sandy environments, reducing the wind pressure and wind and sand impact on the blades, ensuring the safety of the blades and improving their service life. Attached Figure Description

[0018] Figure 1 This is a structural block diagram of the wind turbine forward and reverse rotation adjustment and protection system of the present invention;

[0019] Figure 2 This is a flowchart of the wind turbine blade forward / reverse rotation adjustment protection method of the present invention;

[0020] Figure 3 This is a schematic diagram of the pulse output of a PLC control system.

[0021] Figure 4 A schematic diagram of the program for adjusting the stepper motor to reverse in a strong wind and weak sand environment;

[0022] Figure 5 This is a schematic diagram of the program for adjusting the stepper motor to reverse in a strong wind and sand environment. Detailed Implementation

[0023] The invention will now be further described with reference to the accompanying drawings.

[0024] like Figure 2 As shown, a method for adjusting and protecting wind turbine blades in windy and sandy environments involves monitoring wind speed using a wind speed sensor and monitoring the vibration of the wind turbine blades using an integrated vibration transmitter. The signals from the wind speed sensor and the integrated vibration transmitter are transmitted and connected to the control system. Similarly, the signal from the closed-loop stepper driver of the stepper motor driving the wind turbine blades is also transmitted and connected to the control system. The control system sends pulses or control signals to control the closed-loop stepper driver, which in turn drives the stepper motor to adjust its forward and reverse rotation in windy and sandy environments. Preferably, as... Figure 3 As shown, the control system is a PLC control system that can generate high-frequency pulses. After the PLC control system is powered on, when X1 is turned on, Y0 continuously outputs 800 pulses at an output frequency of 1500Hz.

[0025] Wind speed includes a weak wind speed range (v1, v2) and a strong wind speed range (v3, v4); vibration includes a weak vibration range (f1, f2) and a strong vibration range (f3, f4); the fan blades, when driven in reverse by a stepper motor, have four settings: no adjustment limit, fine adjustment limit, significant adjustment limit, and direct adjustment limit; wind speed and vibration during stepper motor reverse adjustment include the following four cases:

[0026] When the wind speed is in the weak wind range (v1, v2) and the vibration is in the weak vibration range (f1, f2), it indicates a weak wind and weak sand environment. There is no need to adjust the stepper motor to reverse, and the limiting gear does not require adjustment. Since weak wind and weak sand have very little damaging effect on the wind turbine blades, no adjustment is necessary.

[0027] When the wind speed is in the weak wind range (v1, v2) and the vibration is in the strong vibration range (f3, f4), it indicates a weak wind and strong sand environment. The micro-adjustment stepper motor reverses, which is the micro-adjustment limit setting. Because the presence of strong sand will have a certain impact on the wind turbine blades, the micro-adjustment stepper motor reverses to reduce the wind turbine blade speed.

[0028] When the wind speed is in the strong wind range (v3, v4) and the vibration is in the strong vibration range (f3, f4), it indicates a strong wind and sand environment. The stepper motor should be reversed, indicating a clear adjustment limit. Since strong sand exerts impact resistance on the wind turbine blades, it limits the blade speed to some extent under strong winds. Therefore, reversing the motor minimizes the blade speed, providing a clear adjustment limit and reducing the destructive impact of strong winds on the blades.

[0029] When the wind speed is in the strong wind range (v3, v4) and the vibration is in the weak vibration range (f1, f2), it indicates a strong wind and weak sand environment. Directly adjusting the stepper motor to reverse is a direct adjustment limit setting. Since the resistance of weak sand to the wind turbine blades is relatively small, strong wind is the main source of damage to the blades, and strong wind can directly damage the blades in a weak sand environment. Therefore, reducing the blade speed to a stop when the motor reverses is a direct adjustment limit to protect the safety of the wind turbine blades.

[0030] Wherein: wind speed values ​​are represented by v, v1 represents the minimum wind speed in the weak wind zone, v2 represents the maximum wind speed in the weak wind zone, v3 represents the minimum wind speed in the strong wind zone, and v4 represents the maximum wind speed in the strong wind zone; vibration values ​​are represented by f, f1 represents the minimum vibration value in the weak vibration zone, f2 represents the maximum vibration value in the weak vibration zone, f3 represents the minimum vibration value in the strong vibration zone, and f4 represents the maximum vibration value in the strong vibration zone.

[0031] This invention utilizes a PLC system design, employing an integrated vibration transmitter and wind speed sensor to simulate wind and sand conditions and wind speed, respectively. When the stepper motor reverses, the analog signal is converted into a digital signal via an A / D module and input into the PLC. After a series of program executions, the PLC drives the stepper motor to reverse via an SM808D stepper driver. Therefore, by detecting wind speed and wind and sand, the environmental state of the wind turbine can be determined. This allows for the protection of the wind turbine blades by adjusting the stepper motor to reverse in windy and sandy environments, reducing wind pressure and wind and sand impact on the blades, ensuring blade safety, and extending service life.

[0032] like Figure 4 As shown, when adjusting the stepper motor to reverse in a strong wind and weak sand environment, the PLC control system sends a pulse, M14 is turned on, when D0>40, M22 is turned on, and after M23 is turned on, the stepper motor reverses, T0 is turned on for 3 seconds, and after 3 seconds T0 is turned off, the stepper motor stops moving.

[0033] like Figure 5 As shown, when adjusting the stepper motor to reverse in a strong wind and sand environment, the PLC control system sends a pulse. When D1>50, M32 is turned on. After M33 is turned on, the stepper motor reverses. T1 is turned on and timed for 3 seconds. After 3 seconds, T1 is turned off and the stepper motor stops moving.

[0034] like Figure 1 As shown, a wind turbine blade forward / reverse rotation adjustment and protection system for wind turbines in environments with excessive wind speed and sandstorms includes a power supply, a PLC control system, wind turbine blades, a touch screen, a stepper motor, a closed-loop stepper driver, an integrated vibration transmitter, and a wind speed sensor. The power supply provides power to the PLC control system, touch screen, stepper motor, closed-loop stepper driver, integrated vibration transmitter, and wind speed sensor. The PLC control system controls the stepper motor through the closed-loop stepper driver. The touch screen is connected to the PLC control system. The integrated vibration transmitter and wind speed sensor are respectively connected to the PLC control system for signal transmission. The integrated vibration transmitter is installed at the bearing housing of the wind turbine blades or the bearing housing of the stepper motor. The wind turbine blades include the rotor blades of a horizontal axis wind turbine generator set. As a preferred choice, the power supply model is DZ47-63, the PLC control system model is FX1N-40MT, the touch screen model is MCGS TPC7062Ti, the stepper motor model is 130AEA10025-SH3, the closed-loop stepper driver model is SM808D, the integrated vibration transmitter model is HZD-B-8B, and the wind speed sensor model is TXY-FS.

[0035] A stepper motor is an open-loop control element that converts electrical pulse signals into angular or linear displacement. Under non-overload conditions, the motor's speed and stopping position depend only on the frequency and number of pulse signals, and are unaffected by load changes. When the stepper driver receives a pulse signal, it drives the stepper motor to rotate a fixed angle in a set direction, called the "step angle." Its rotation occurs step by step at fixed angles. The angular displacement can be controlled by controlling the number of pulses, thus achieving accurate positioning; simultaneously, the motor's speed and acceleration can be controlled by controlling the pulse frequency, thus achieving speed regulation.

[0036] A stepper motor driver is an actuator that converts electrical pulses into angular displacement. When a stepper driver receives a pulse signal, it drives the stepper motor to rotate a fixed angle in a set direction, rotating step by step at fixed angles. The angular displacement can be controlled by controlling the number of pulses, thus achieving accurate positioning; simultaneously, the speed and acceleration of the motor can be controlled by controlling the pulse frequency, thus achieving speed regulation and positioning. Stepper motors require drivers that can provide fast current rise and fall rates, making the current waveform as close to rectangular as possible. It has a circuit for releasing current flow during cutoff periods to reduce the back electromotive force at the winding ends, accelerate current decay, and achieve high power and efficiency. The SM808D closed-loop stepper driver is a new low-voltage hybrid servo product developed based on years of experience in low-voltage servo systems.

[0037] An integrated vibration transmitter is a high-precision vibration measurement system. The sensor can be directly connected to a PLC to achieve high-precision vibration measurement. Similar to vibrations generated by a moving coil cutting a magnetic circuit, the frequency converter requires a DC 24V power supply for easy installation and maintenance. It is mainly used for preliminary diagnosis of rotating machinery faults or for improving laboratory products, ensuring basic improvements, preparing for service in advance, reducing accident risks, and improving work efficiency.

[0038] An anemometer is a device used to measure actual wind speed. It is small, lightweight, portable, and easy to assemble. To efficiently and quickly acquire wind speed information, the product is designed in integrated, split, and three-cup styles.

[0039] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for adjusting and protecting wind turbine blades to rotate forward and backward under conditions of high wind speed and sandstorms, characterized in that: Wind speed is monitored by a wind speed sensor, and vibration of the wind turbine blades is monitored by an integrated vibration transmitter. The signals from the wind speed sensor and the integrated vibration transmitter are transmitted and connected to the control system. The signals from the closed-loop stepper driver that drives the stepper motor of the wind turbine blades are also transmitted and connected to the control system. The control system sends pulses or control signals to control the closed-loop stepper driver, which drives the stepper motor to adjust the forward and reverse rotation of the stepper motor in windy and sandy environments. Wind speed includes weak wind speed range (v1, v2) and strong wind speed range (v3, v4); vibration includes weak vibration range (f1, f2) and strong vibration range (f3, f4); the fan blades have four settings when driven in reverse by a stepper motor: no adjustment limit, fine adjustment limit, obvious adjustment limit, and direct adjustment limit. When the wind speed is in the weak wind speed range (v1, v2) and the vibration is in the weak vibration range (f1, f2), it indicates a weak wind and sand environment. There is no need to adjust the stepper motor to reverse, and it is a condition where no adjustment of the limit gear is required. When the wind speed is in the weak wind speed range (v1, v2) and the vibration is in the strong vibration range (f3, f4), it indicates a weak wind and strong sand environment. The micro-adjustment stepper motor reverses, which is the micro-adjustment limit gear. When the wind speed is in the strong wind range (v3, v4) and the vibration is in the strong vibration range (f3, f4), it indicates a strong wind and sand environment. The stepper motor should be reversed, which is a clear adjustment limit setting. When the wind speed is in the strong wind range (v3, v4) and the vibration is in the weak vibration range (f1, f2), it indicates a strong wind and weak sand environment. Directly adjusting the stepper motor to reverse is a direct adjustment of the limit gear.

2. The method for adjusting and protecting wind turbine blades in the direction of forward and reverse rotation under conditions of excessive wind speed and sandstorms, as described in claim 1, is characterized in that: The control system is a PLC control system capable of generating high-frequency pulses. After the PLC control system is powered on, when X1 is turned on, Y0 continuously outputs 800 pulses at an output frequency of 1500Hz.

3. The method for adjusting and protecting wind turbine blades in the direction of forward and reverse rotation under conditions of excessive wind speed and sandstorms, as described in claim 2, is characterized in that: When adjusting the stepper motor to reverse in a strong wind and weak sand environment, the PLC control system sends a pulse, M14 is turned on, and when D0>40, M22 is turned on. After M23 is turned on, the stepper motor reverses, T0 is turned on for 3 seconds, and after 3 seconds T0 is turned off, the stepper motor stops moving.

4. The method for adjusting and protecting wind turbine blades in the direction of forward and reverse rotation under conditions of excessive wind speed and sandstorms, as described in claim 2, is characterized in that: When adjusting the stepper motor to reverse in a strong wind and sand environment, the PLC control system sends a pulse. When D1>50, M32 is turned on. After M33 is turned on, the stepper motor reverses. T1 is turned on and timed for 3 seconds. After 3 seconds, T1 is turned off and the stepper motor stops moving.

5. A wind turbine blade forward / reverse rotation adjustment and protection system based on the wind speed and sandstorm environment protection method described in claim 2, characterized in that: The system includes a power supply, a PLC control system, fan blades, a touch screen, a stepper motor, a closed-loop stepper driver, an integrated vibration transmitter, and a wind speed sensor. The power supply provides power to the PLC control system, the touch screen, the stepper motor, the closed-loop stepper driver, the integrated vibration transmitter, and the wind speed sensor. The PLC control system controls the stepper motor through the closed-loop stepper driver. The touch screen is connected to the PLC control system. The integrated vibration transmitter and the wind speed sensor are respectively connected to the PLC control system for signal transmission.

6. A wind turbine blade forward / reverse rotation adjustment and protection system based on the wind speed and sandstorm environment protection method described in claim 5, characterized in that: The integrated vibration transmitter is installed at the bearing housing of the fan blade or the bearing housing of the stepper motor.

7. A wind turbine blade forward / reverse rotation adjustment and protection system based on the wind speed and sandstorm environment protection method described in claim 5, characterized in that: The wind turbine blades include the rotor blades of a horizontal axis wind turbine generator set.

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