Method and system for adjusting and protecting positive and negative rotation of fan blade in environment with too large wind speed and wind sand

Abstract

The invention discloses a fan blade forward and reverse rotation adjustment protection method and system under the environment of too large wind speed and wind sand. The system comprises a power source, a PLC control system, fan blades, a touch screen, a stepping motor, a closed-loop stepping driver, an integrated vibration transmitter and a wind speed sensor. Wind speed monitoring is carried out through a wind speed sensor, vibration monitoring is carried out on fan blades through an integrated vibration transmitter, the wind speed sensor and the integrated vibration transmitter are in signal transmission connection with a control system, and a closed-loop stepping driver of a stepping motor for driving the fan blades is in signal transmission connection with the control system. The control system sends out a pulse or a control signal to control the closed-loop stepping driver, and the closed-loop stepping driver drives the stepping motor to act so as to adjust forward and reverse rotation of the stepping motor in wind and sand environments. The environment state of the fan can be judged by detecting the wind speed and the wind and sand, so that the aim of protecting fan blades by adjusting the reverse rotation of the stepping motor in the wind and sand environment is achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of wind turbine blade protection, and in particular relates to a method and system for regulating and protecting blades in forward and reverse directions under an environment with excessive wind speed and sandstorms. Background Art

[0002] The utilization cost of wind turbine blades accounts for about 20%-30% of the total utilization cost of the entire wind power system. The cost of wind farm equipment construction can generally be roughly divided into wind power equipment construction costs, installation costs, construction projects and other costs. Taking the construction of a 50MW wind farm as an example, about 70% of the construction cost mainly comes from wind power equipment installation costs; 94% of the construction cost of wind power equipment installation costs mainly comes from wind power equipment; 80% of the cost of wind power equipment installation costs comes from the construction cost of wind turbine generator sets, and 17% of the cost comes from the construction cost of wind power towers. According to this calculation, the construction cost of the entire wind turbine generator set is approximately equivalent to 51% of the total power investment of the entire wind farm, and the tower unit cost is approximately equivalent to 11% of the total wind power investment. The equipment purchase and maintenance costs of both will be the main investment costs of the entire wind farm in the early stage of construction. The design of special blades for wind turbines needs to have the basic characteristics of large blade size, complex shape, high precision technical requirements, uniform distribution of quality characteristics and good high temperature weather resistance. At present, the annual market size of wind turbine blades is about 15-20 billion yuan. When a blade fails, especially when a single blade breaks, the balance shafts of the three blades are automatically interrupted in the rotating state, and the generator set vibrates violently instantly; if the generator set operation protection action fails or the control vehicle protection device delays stopping action for some reason, this will not only cause serious mechanical damage to the bearing system and the system tower of the entire generator set, but also may directly lead to serious damage to the entire generator set. Moreover, before the generator set starts braking, the broken blade may soon collide with the two adjacent blades or the shaft tower of the unit, increasing the economic losses that may be caused by this accident. After the blade wind turbine fails to supply power due to voltage failure, the wind farm must shut down for maintenance in time, and must continue to wait for the best operating conditions with slight wind or only light wind or no wind. This not only generates high mechanical and electrical maintenance and repair costs, but also loses the opportunity to generate electricity due to "wind abandonment". Various types of failed wind turbine accidents with severely damaged blades result in direct and indirect social and economic losses of nearly one million yuan. From the analysis of the current status of daily blade maintenance management of various types of wind power operating companies, there is a lack of awareness of the importance of daily maintenance management of damaged blades, lax quality control of the daily blade maintenance management process, and insufficient investment in daily maintenance management. As a result, the safety hazards of damaged blades in the actual wind power operation process have continued to increase sharply over the years, which may directly lead to various types of failed wind turbine accidents at any time and seriously affect the social and economic benefits of wind power companies.

[0003] The impeller main shaft of the fan is responsible for automatically converting the internal wind energy into various mechanical kinetic energy. It is composed of fan blades, hubs, etc. The blades convert the various kinetic energy of the air into various mechanical kinetic energy through the blades and the impeller main shaft, and then convert its kinetic energy into wind turbine electrical energy through the generator. The size and shape of the blades directly determine the efficiency of the fan energy flow conversion and the operating power and performance of the wind turbine. Therefore, large wind power transmission blades have always been an important core technology in the design of large wind turbines. During the operation of the fan, under the influence of wind pressure caused by excessive wind speed and the impact of excessive wind and sand, the fan blades are prone to breakage, surface cracks, dents, etc. It is particularly important to protect the fan blades in an environment with excessive wind speed or excessive wind and sand. Summary of the invention

[0004] Purpose of the invention: In order to overcome the deficiencies in the prior art, the present invention provides a method and system for adjusting and protecting the forward and reverse rotation of fan blades in an environment with excessive wind speed and sand. The method and system can determine the environmental state of the fan by detecting the wind speed and sand, so as to achieve the protection of the fan blades by adjusting the reverse rotation of the stepper motor in strong wind and strong sand or strong wind and weak sand environments.

[0005] Technical solution: To achieve the above-mentioned purpose, the fan blade forward and reverse rotation adjustment and protection method in an environment with excessive wind speed and sandstorm of the present invention monitors the wind speed through a wind speed sensor, monitors the vibration of the fan blades through an integrated vibration transmitter, transmits the signals of the wind speed sensor and the integrated vibration transmitter to the control system, and transmits the signals of the closed-loop stepper driver of the stepper motor that drives the fan blades to the control system; the control system sends a pulse or control signal to control the closed-loop stepper driver, and the closed-loop stepper driver drives the stepper motor to move, so as to adjust the forward and reverse rotation of the stepper motor in a windy and sandstorm environment.

[0006] Furthermore, the wind speed includes a weak wind speed interval (v1, v2) and a strong wind speed interval (v3, v4); the vibration includes a weak vibration interval (f1, f2) and a strong vibration interval (f3, f4); the fan blades include four gears when driven by a stepper motor to reverse, including 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 weak sand environment, and there is no need to adjust the stepper motor reverse, which is a limit gear that does not need to be adjusted;

[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, and the fine-tuning stepper motor reverses, which belongs to the fine-tuning limit gear;

[0009] When the wind speed is in the strong wind speed range (v3, v4) and the vibration is in the strong vibration range (f3, f4), it indicates a strong wind and strong sand environment, and the stepper motor is obviously adjusted to reverse, which is an obvious adjustment limit gear;

[0010] When the wind speed is in the strong wind speed 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 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 1500 Hz.

[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 3s, and after 3s, T0 is disconnected and 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 for 3s, and after 3s, T1 is disconnected and the stepper motor stops moving.

[0014] A fan blade forward and reverse rotation regulation and protection system of a fan blade forward and reverse rotation regulation and protection method under an environment with excessive wind speed and sand comprises 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 is used to supply 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 arranged at the bearing seat of the fan blade or the bearing seat of the stepper motor.

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

[0017] Beneficial effect: The present invention adopts the PLC system design, uses an integrated vibration transmitter and a wind speed sensor to respectively simulate the conditions of wind and sand and wind speed. When adjusting the reverse rotation of the stepper motor, the analog quantity is converted into a digital quantity through the A / D module and input into the PLC. After the PLC runs a series of programs, it drives the stepper motor to reverse through the SM808D stepper driver. Therefore, it is possible to judge the environmental state of the fan by detecting the wind speed and wind and sand, so as to achieve the protection of the fan blades by adjusting the reverse rotation of the stepper motor in a windy and sandy environment, reduce the wind pressure and wind and sand impact force on the blades, ensure the safety of the blades and increase the service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural block diagram of the fan blade forward and reverse rotation regulating and protecting system of the present invention;

[0019] Figure 2 It is a flowchart of the fan blade forward and reverse rotation regulating protection method of the present invention;

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

[0021] Figure 4 This is a schematic diagram of the procedure for adjusting the reversal of the stepper motor in a strong wind and weak sand environment;

[0022] Figure 5 This is a schematic diagram of the program for adjusting the reversal of the stepper motor in a strong wind and sand environment. DETAILED DESCRIPTION

[0023] The present invention will be further described below in conjunction with the accompanying drawings.

[0024] like Figure 2 As shown, the protection method for adjusting the forward and reverse rotation of the fan blades in an environment with excessive wind speed and sandstorms is to monitor the wind speed through a wind speed sensor, monitor the vibration of the fan blades through an integrated vibration transmitter, connect the wind speed sensor and the integrated vibration transmitter signal transmission to the control system, and connect the closed-loop stepper driver signal transmission of the stepper motor driving the fan blades to the control system. The control system sends a pulse or control signal to control the closed-loop stepper driver, and the closed-loop stepper driver drives the stepper motor to move, so as to adjust the forward and reverse rotation of the stepper motor in a windy and sandstorm environment. As a preferred embodiment, 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 1500 Hz.

[0025] Wind speed includes weak wind speed interval (v1, v2) and strong wind speed interval (v3, v4); vibration includes weak vibration interval (f1, f2) and strong vibration interval (f3, f4); the fan blades include four gears when driven by a stepper motor to reverse, including no adjustment limit, micro-adjustment limit, obvious adjustment limit and direct adjustment limit; wind speed and vibration include the following four situations in adjusting the stepper motor reverse:

[0026] 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 weak sand environment, and there is no need to adjust the stepper motor reverse, which is a limit gear that does not require adjustment. Since weak wind and weak sand have very little destructive effect on the wind blades, no adjustment is required.

[0027] 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, and the fine-tuning stepper motor reverses, which belongs to the fine-tuning limit gear. Since the presence of strong sand will have a certain impact on the fan blades, the fine-tuning stepping reverses to reduce the fan blade speed.

[0028] When the wind speed is in the strong wind speed range (v3, v4) and the vibration is in the strong vibration range (f3, f4), it indicates a strong wind and strong sand environment. The stepper motor is obviously adjusted to reverse, which is an obvious adjustment limit gear. Since strong sand has impact resistance on the fan blades, it will limit the speed of the fan blades under strong winds to a certain extent. Therefore, when the motor reverses, the fan blade speed can be reduced as much as possible, which is an obvious adjustment limit, reducing the destructive effect of strong wind on the fan blades.

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

[0030] Among them: the wind speed value is represented by v, v1 represents the lowest wind speed value in the weak wind interval, v2 represents the highest wind speed value in the weak wind interval, v3 represents the lowest wind speed value in the strong wind speed interval, and v4 represents the highest wind speed value in the strong wind speed interval; the vibration value is represented by f, f1 represents the lowest vibration value in the weak vibration interval, f2 represents the highest vibration value in the weak vibration interval, f3 represents the lowest vibration value in the strong vibration interval, and f4 represents the highest vibration value in the strong vibration interval.

[0031] The present invention adopts PLC system design, uses an integrated vibration transmitter and a wind speed sensor to respectively simulate the conditions of wind and sand and wind speed, and when adjusting the reverse rotation of the stepper motor, converts the analog quantity into a digital quantity through the A / D module and inputs it into the PLC. After the PLC runs a series of programs, the SM808D stepper driver drives the stepper motor to reverse. Therefore, the environmental state of the fan can be judged by detecting the wind speed and wind and sand, so as to achieve the protection of the fan blades by adjusting the reverse rotation of the stepper motor in a wind and sand environment, reduce the wind pressure and wind and sand impact force on the blades, ensure the safety of the blades and increase the 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, and when D0>40, M22 is turned on. After M23 is turned on, the stepper motor reverses, T0 is turned on for 3s, and after 3s, T0 is disconnected and the stepper motor stops.

[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 for 3s, and after 3s, T1 is disconnected and the stepper motor stops.

[0034] like Figure 1 As shown, the blade forward and reverse rotation regulation and protection system of the blade forward and reverse rotation regulation and protection method under the environment of excessive wind speed and sandstorm includes a power supply, a PLC control system, a fan blade, a touch screen, a stepper motor, a closed-loop stepper driver, an integrated vibration transmitter and a wind speed sensor; the power supply is used to power 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. The integrated vibration transmitter is arranged at the bearing seat of the fan blade or the bearing seat of the stepper motor. The fan blade includes the rotor blade of the horizontal axis wind turbine generator set. Preferably, the model of the power supply is DZ47-63, the model of the PLC control system is FX1N-40MT, the model of the touch screen is MCGS TPC7062Ti, the model of the stepper motor is 130AEA10025-SH3, the model of the closed-loop stepper driver is SM808D, the model of the integrated vibration transmitter is HZD-B-8B, and the model of the wind speed sensor is TXY-FS.

[0035] Among them, the stepper motor is an open-loop control element that converts electrical pulse signals into angular displacement or linear displacement. In the case of non-overload, the motor's speed and stop position only depend on the frequency and number of pulses of the pulse signal, and are not affected by load changes. When the stepper driver receives a pulse signal, it drives the stepper motor to rotate a fixed angle in the set direction, called the "step angle", and its rotation runs step by step at a fixed angle. The angular displacement can be controlled by controlling the number of pulses to achieve the purpose of accurate positioning; at the same time, the speed and acceleration of the motor rotation can be controlled by controlling the pulse frequency to achieve the purpose of speed regulation.

[0036] The stepper motor driver is an actuator that converts electrical pulses into angular displacement. When the stepper driver receives a pulse signal, it drives the stepper motor to rotate a fixed angle in the set direction, and its rotation runs step by step at a fixed angle. The angular displacement can be controlled by controlling the number of pulses to achieve the purpose of accurate positioning; at the same time, the speed and acceleration of the motor rotation can be controlled by controlling the pulse frequency to achieve the purpose of speed regulation and positioning. The stepper motor requires the driver to provide a faster current rise and fall speed to make the current waveform as close to a rectangle as possible. It has a circuit for releasing current flow during the cut-off period to reduce the back electromotive force at both ends of the winding, accelerate the current decay, and has higher power and efficiency. The SM808D closed-loop stepper driver is a new low-voltage hybrid servo product developed based on many years of experience in low-voltage servo systems.

[0037] The integrated vibration transmitter is a high-precision vibration measurement system. The sensor can be directly connected to the PLC to achieve a high-precision vibration measurement system. It is the same as that produced by cutting the magnetic circuit through the moving coil, so the inverter must provide a DC24V power supply when working, which is convenient for installation and maintenance. It is mainly used for preliminary diagnosis of rotating machinery failures or improvement of laboratory products to ensure basic improvements, make service preparations in advance, reduce accident risks, and improve work efficiency.

[0038] The wind speed sensor is a device used to measure the actual wind speed. It is small and light, easy to carry and easy to assemble. In order to effectively and quickly obtain wind speed information, the product is designed into integrated, split and three-cup styles.

[0039] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for adjusting and protecting the blades in positive and negative rotation under the conditions of excessive wind speed and sandstorm, characterized in that: The wind speed is monitored by a wind speed sensor, the vibration of the fan blades is monitored by an integrated vibration transmitter, the wind speed sensor and the integrated vibration transmitter signal transmission is connected to the control system, and the closed-loop stepper driver signal of the stepper motor driving the fan blades is connected to the control system; the control system sends a pulse or control signal to control the closed-loop stepper driver, and the closed-loop stepper driver drives the stepper motor to operate, so as to adjust the forward and reverse rotation of the stepper motor in a windy and sandstorm environment.

2. The method for adjusting and protecting the blades in forward and reverse rotation under the conditions of excessive wind speed and sandstorm according to claim 1 is characterized in that: The wind speed includes a weak wind speed interval (v1, v2) and a strong wind speed interval (v3, v4); the vibration includes a weak vibration interval (f1, f2) and a strong vibration interval (f3, f4); the fan blades include four gears when driven by a stepper motor to reverse, including no adjustment limit, micro-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 weak sand environment, and there is no need to adjust the stepper motor reverse, which is a limit gear that does not need to be adjusted; 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, and the fine-tuning stepper motor reverses, which belongs to the fine-tuning limit gear; When the wind speed is in the strong wind speed range (v3, v4) and the vibration is in the strong vibration range (f3, f4), it indicates a strong wind and strong sand environment, and the stepper motor is obviously adjusted to reverse, which is an obvious adjustment limit gear; When the wind speed is in the strong wind speed 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 gear.

3. The method for adjusting and protecting the blades in forward and reverse rotation under the conditions of excessive wind speed and sandstorm according to claim 2 is characterized in that: 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 connected, Y0 continuously outputs 800 pulses at an output frequency of 1500Hz.

4. The method for adjusting and protecting the blades in forward and reverse rotation under the conditions of excessive wind speed and sandstorm according to claim 3 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 3s, and after 3s, T0 is disconnected and the stepper motor stops.

5. The method for adjusting and protecting the blades in forward and reverse rotation under the conditions of excessive wind speed and sandstorm according to claim 3 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 for 3s, and after 3s, T1 is disconnected and the stepper motor stops.

6. A fan blade forward and reverse rotation regulating and protecting system based on the fan blade forward and reverse rotation regulating and protecting method in an environment with excessive wind speed and sandstorm according to claim 3, characterized in that: It includes a power supply, a PLC control system, a fan blade, a touch screen, a stepper motor, a closed-loop stepper driver, an integrated vibration transmitter and a wind speed sensor; the power supply is used to supply 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.

7. A fan blade forward and reverse rotation regulating and protecting system based on the fan blade forward and reverse rotation regulating and protecting method in an environment with excessive wind speed and sandstorm according to claim 6, characterized in that: The integrated vibration transmitter is arranged at the bearing seat of the fan blade or the bearing seat of the stepper motor.

8. A fan blade forward and reverse rotation regulating and protecting system based on the fan blade forward and reverse rotation regulating and protecting method in an environment with excessive wind speed and sandstorm according to claim 7, characterized in that: The fan blades include rotor blades of a horizontal-axis wind turbine generator set.

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