A method, system, device and medium for reverse wind starting of a fan

Abstract

The application relates to a fan adverse wind starting method, system, device and medium, and the method specifically comprises the following steps: receiving a fan starting signal; obtaining a pulsating direct-current voltage, the pulsating direct-current voltage being generated by a reverse electromotive force generated by fan reverse rotation and passing through a diode arranged in the fan; judging whether the pulsating direct-current voltage is less than a set threshold value; if yes, generating a soft starting voltage by a controller according to the pulsating direct-current voltage; preventing the fan from reversing by the reverse rotation torque generated by the soft starting voltage acting on the fan until the voltage value of the pulsating direct-current voltage is zero; and inputting a forward rotation voltage according to the fan starting signal to normally operate the fan when the voltage value of the pulsating direct-current voltage is zero. The application realizes the normal starting of the fan in the adverse wind state, and since the reverse rotation torque for preventing the fan from reversing acting on the fan is intermittent, the damage of the adverse wind starting of the fan to the internal elements and mechanical structure of the fan is reduced as much as possible.

Description

Technical Field

[0001] This application relates to the field of wind turbine control methods, and in particular to a wind turbine reverse wind start-up method, system, equipment and medium. Background Technology

[0002] As a commonly used ventilation device, fans are often found in workplaces with poor air quality, such as factories and farms. These places have complex working conditions, and when fans are working, they are easily affected by external factors and may start up against the wind.

[0003] For fans that use permanent magnet motors as their power source, when there is external natural wind, if the fan is started against the wind, a large back electromotive force will appear inside the fan. This back electromotive force will, on the one hand, lead to an increase in starting torque, generating a large impact force that can damage the drive equipment and transmission structure inside the fan; on the other hand, it will cause armature reaction, resulting in excessively high maximum voltage between commutator segments, which can easily cause sparks or even motor arcing, causing a significant increase in the internal operating temperature of the fan, demagnetizing the permanent magnets, and thus affecting the service life of the fan. Summary of the Invention

[0004] To prevent armature reaction from occurring when a wind turbine starts up against the wind, this application provides a method, system, device, and medium for starting a wind turbine against the wind.

[0005] Firstly, this application provides a method for starting a wind turbine against the wind.

[0006] A method for starting a wind turbine against the wind includes the following steps:

[0007] Receive the fan start signal;

[0008] A pulsating DC voltage is obtained, which is generated by the reverse electromotive force generated by the fan reversing and passed through a diode installed inside the fan;

[0009] Determine whether the pulsating DC voltage is less than a set threshold;

[0010] If so, a soft-start voltage is generated according to the pulsed DC voltage control controller, wherein the maximum value of the soft-start voltage is less than or equal to the pulsed DC voltage, and the direction is opposite to that of the pulsed DC voltage;

[0011] The soft-start voltage is applied to the fan to generate a torque that prevents the fan from reversing, until the voltage value of the pulsating DC voltage is zero.

[0012] When the voltage value of the pulsating DC voltage is zero, the forward voltage is input to operate the fan normally.

[0013] By adopting the above technical solution, when the fan is started, if the fan reverses due to external wind, a soft-start voltage is first input to the fan through the controller. The soft-start voltage acts on the fan to generate a torque that prevents the fan from reversing. This torque is opposite in direction to the torque generated by the external wind, thus stopping the fan from reversing before it can run normally, reducing the damage to the fan's internal components caused by starting against the wind. In addition, since the maximum value of the input soft-start voltage is less than or equal to the pulsating DC voltage generated by the fan reversing, the impact on the fan's internal components when preventing the fan from reversing is very small, effectively protecting the fan.

[0014] Preferably, after determining whether the pulsating DC voltage is less than a set threshold, the method further includes the following steps:

[0015] If the pulsating DC voltage is greater than or equal to the set threshold, the fan will be prevented from starting.

[0016] By adopting the above technical solution, when the pulsating DC voltage is too large and exceeds the reverse rectification limit of the internal diode of the fan, the fan will receive a start signal and prevent the fan from operating normally, thereby preventing damage to the internal components of the fan caused by the reverse electromotive force and pulsating DC voltage generated by the fan reversing.

[0017] Preferably, after the step of preventing the fan from starting if the pulsating DC voltage is greater than or equal to the set threshold, the method further includes the following steps:

[0018] An alarm signal is generated to control the alarm circuit to trigger an alarm, indicating that the fan is in an abnormal state.

[0019] By adopting the above technical solution, when the pulsating DC voltage generated inside the fan is too large due to excessive external wind, it indicates that the external wind has had a significant impact on the fan. An alarm is sent to prompt personnel to take measures to adjust or protect the fan, preventing further damage to the fan from the external environment.

[0020] Preferably, the waveform of the soft-start voltage is a periodic rectangular wave, and the duty cycle of the soft-start voltage is adjusted based on the pulsating DC voltage and a preset adjustment rule to make the pulsating DC voltage decrease smoothly.

[0021] By adopting the above technical solution, the torque that prevents the fan from reversing is applied to the fan intermittently, reducing the impact force generated by the sudden stop of the fan blades and avoiding damage to the mechanical structure of the fan; and it can generate soft-start voltages with different duty cycles according to the different values ​​of the pulsating DC voltage, and input soft-start voltages in a targeted manner according to the different headwind conditions of the fan.

[0022] Preferably, after the step of generating the soft-start voltage according to the pulsed DC voltage control controller, the method further includes the following steps:

[0023] A discharge signal is generated and a preset discharge circuit is activated, the discharge circuit being used to release the high-voltage DC pulse generated by the anti-fan reverse torque acting on the fan.

[0024] By adopting the above technical solution, the high-voltage DC pulse generated by the force that prevents the fan from reversing can be released in a timely manner, reducing the impact of the high-voltage DC pulse on the internal components of the fan and thus reducing the impact on the fan's lifespan.

[0025] Preferably, the discharge circuit includes a varistor and a discharge tube, the varistor and the discharge tube are connected in parallel, one end of the parallel circuit is coupled to the fan and the other end is grounded.

[0026] By adopting the above technical solution, the varistor starts to operate before the discharge tube is turned on, clamping the transient overvoltage and discharging the large current. When the discharge tube is turned on, it will be connected in parallel with the varistor to shunt the current, reducing the current pressure on the varistor and thus shortening the time for the varistor to carry a large current, which helps to slow down the performance degradation of the varistor.

[0027] Preferably, the step of inputting a forward voltage to operate the fan normally also includes the following step:

[0028] After inputting the low-speed forward voltage in the first time period, the rated forward voltage is input, where the rated forward voltage is greater than the low-speed forward voltage.

[0029] By adopting the above technical solution, after preventing the fan from reversing, a low-speed forward voltage lower than the rated voltage is first input to make the fan work at a speed lower than the rated speed, so as to eliminate the impact of backwind start on the normal operation of the fan; after a period of time, the rated forward voltage is then input, and the fan completes the backwind start and starts working normally.

[0030] Secondly, the wind turbine reverse-wind start-up system provided in this application includes the following modules:

[0031] The wind turbine start signal receiving module is used to receive the wind turbine start signal;

[0032] A pulsating DC voltage acquisition module is used to acquire pulsating DC voltage.

[0033] The pulsating DC voltage detection module is used to determine whether the pulsating DC voltage is less than a set threshold.

[0034] A soft-start voltage generation module is used to generate a soft-start voltage based on the pulsed DC voltage control controller.

[0035] A forward rotation voltage generation module is used to input a forward rotation voltage based on the fan start signal;

[0036] Alarm signal generation module, used to generate alarm signals;

[0037] The discharge signal generation module is used to generate discharge signals.

[0038] Thirdly, this application provides a computer device that adopts the following technical solution: it includes a memory and a processor, wherein the memory stores a computer program that can be loaded by the processor and executed as any of the above-described wind turbine reverse wind start-up methods.

[0039] Fourthly, this application provides a computer-readable storage medium that stores a program capable of being loaded by a processor and executed for any of the above-mentioned wind turbine reverse-wind start-up methods.

[0040] In summary, this application includes at least one of the following beneficial technical effects:

[0041] 1. It enables the normal start-up of the fan in the face of headwind, and the soft start voltage generated by the controller is applied to the fan to produce an intermittent torque that prevents the fan from reversing, thereby reducing the damage to the internal components and mechanical structure of the fan caused by headwind start-up.

[0042] 2. When excessive external wind damages the fan, an alarm will be issued to prompt personnel to adjust the current status of the fan and prevent the fan from being in a harmful environment for a long time, which would reduce the service life of the fan.

[0043] 3. Promptly release the high-voltage DC pulses generated during the wind turbine's reverse-wind start-up process to reduce the damage caused by the high-voltage DC pulses to the wind turbine and ensure that the high-voltage DC pulses do not affect the power system to which the wind turbine is connected. Attached Figure Description

[0044] Figure 1 This is a flowchart of a method for starting a wind turbine against the wind, according to an embodiment of this application.

[0045] Figure 2 This is a discharge circuit diagram of a fan starting method against wind according to an embodiment of this application.

[0046] Figure 3 This is a system block diagram of a wind turbine reverse-wind start-up method provided in an embodiment of this application.

[0047] Figure 4 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application.

[0048] Explanation of reference numerals in the attached diagram: 201, Discharge tube; 202, Varistor; 301, Fan start signal receiving module; 302, Pulsating DC voltage acquisition module; 303, Pulsating DC voltage judgment module; 304, Soft start voltage generation module; 305, Forward rotation voltage generation module; 306, Alarm signal generation module; 307, Discharge signal generation module; 400, Electronic device; 401, Processor; 402, Communication bus; 403, User interface; 404, Network interface; 405, Memory. Detailed Implementation

[0049] To enable those skilled in the art to better understand the technical solutions in this specification, the technical solutions in the embodiments of this specification will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments.

[0050] This application discloses a method for starting a wind turbine against the wind. (Refer to...) Figure 1 A method for starting a wind turbine against the wind includes:

[0051] S101: Receives the fan start signal;

[0052] Specifically, the fan start signal can be entered by personnel through a host computer set on the fan, or it can be generated by personnel directly connecting the fan's start circuit through a switch. After receiving the fan start signal, the fan starts working. If it is detected that the fan is in a headwind state, the fan headwind start method will be executed.

[0053] S102: Obtain pulsating DC voltage;

[0054] Specifically, for fans installed in indoor farms or similar working environments, it's common practice not to install just one row of fans for ventilation. In many scenarios, a set of fans is installed on opposite walls of the work area. This means that if one fan starts first, drawing outside air into the room through the other fan, it generates a strong wind, causing the other fan to rotate. At this point, the other fan is in a headwind state. Simultaneously, the natural wind also causes the fan blades to rotate in the opposite direction. When the fan is in a headwind state, the permanent magnet motor driving the fan begins to cut the magnetic field, generating a reverse electromotive force (EMF). This EMF is rectified in reverse by a diode inside the fan, generating a pulsating DC voltage. A current sensor detects this pulsating DC voltage, indicating that the fan is in a headwind state. The magnitude of the pulsating DC voltage reflects the degree of reverse rotation; a larger pulsating DC voltage indicates a faster reverse rotation speed of the fan blades.

[0055] S103: Determine whether the pulsating DC voltage is less than the set threshold;

[0056] Specifically, the magnitude of the pulsating DC voltage should not exceed the maximum carrying voltage of the diode, nor should it exceed the maximum carrying voltage of the internal components of the fan. For example, for a three-phase AC 380V permanent magnet motor, the threshold can be set to 400V. Of course, the above example is not the only standard for setting the threshold. The specific setting can be set by those skilled in the art according to the actual working scenario, and will not be elaborated here.

[0057] S104: If the pulsating DC voltage is determined to be greater than or equal to the set threshold, then prevent the fan from starting;

[0058] Specifically, when the generated pulsating DC voltage is too large, it indicates that the fan is operating in a relatively extreme environment, such as during typhoons, heavy rainstorms, or personnel conducting experiments. Under the influence of enormous external forces, the fan blades rapidly reverse, and the internal magnetic field of the fan is cut, generating a reverse electromotive force. If the fan is started under these circumstances, an armature reaction will occur inside the fan, causing the maximum voltage between the commutator segments to be too high, resulting in sparks or even motor arcing. This leads to a significant increase in the internal operating temperature of the fan, which can easily cause demagnetization of the permanent magnets inside the fan. Therefore, when the pulsating DC voltage is greater than or equal to the set threshold, the fan power supply should be cut off to prevent the fan from starting.

[0059] S105: Generates an alarm signal to control the alarm circuit to trigger an alarm;

[0060] Specifically, after determining that the pulsating DC voltage is greater than or equal to a set threshold, an alarm signal is generated and an alarm is triggered. The alarm circuit can be an audible and visual alarm, which emits an audible and visual alarm after receiving the alarm signal. In another embodiment of this application, the alarm circuit may also include a wireless signal transmitter for transmitting alarm signals to personnel. When the alarm circuit receives the alarm signal, the wireless signal transmitter sends alarm information to the personnel's smart terminal, prompting the personnel to adjust the current working status of the fan.

[0061] S106: If the pulsating DC voltage is determined to be less than the set threshold, then the controller is controlled to generate a soft-start voltage based on the pulsating DC voltage.

[0062] Specifically, in this embodiment, when the pulsating DC voltage is less than 400V, it indicates that the scenario is suitable for using the method of this application to start up against the wind. First, the controller of this application will generate a soft start voltage. The controller of this application can be a PLC. The PLC adjusts the duty cycle of the soft start voltage input into the fan by PWM modulation of the adjustable external power supply, thereby changing the effective voltage magnitude.

[0063] The duty cycle of the soft-start voltage is adjusted based on the magnitude of the pulsating DC voltage. Since the magnitude of the pulsating DC voltage reflects the degree of wind resistance in the fan, when the detected pulsating DC voltage is large, the armature reaction causes a high maximum voltage between the commutator segments. In this case, the fan should be soft-started with a smaller duty cycle of the soft-start voltage. The duty cycle of the soft-start voltage can be obtained from a preset soft-start voltage meter, which includes the pulsating DC voltage and the corresponding duty cycle value of the soft-start voltage. The soft-start voltage for each specific duty cycle during debugging will be applied continuously for 1 second.

[0064] For example, for a 380V permanent magnet motor, the soft-start voltage can be gradually increased from 0-100V in segments according to the soft-start voltmeter. It should be noted that the selection principle of this soft-start voltage is that it should be within the range that the permanent magnet motor can withstand and should not cause the motor temperature to become too high. Under the premise of meeting the selection principle, those skilled in the art can select a value according to the actual working conditions. By adjusting the soft-start voltage in the above way, the anti-reverse torque generated by the soft-start voltage acting on the fan will intermittently exert a force on the fan, and the fan will slowly prevent the blades from reversing, so that the motor stops reversing. In this way, the impact force generated by preventing the fan from reversing is reduced, and damage to the mechanical structure of the fan is prevented.

[0065] S107: The soft-start voltage generates a torque to prevent the fan from reversing, which acts on the fan to prevent it from reversing until the pulsating DC voltage value is zero.

[0066] Specifically, the reverse torque of the fan is used to slowly and intermittently prevent the fan blades from reversing until the pulsating DC voltage is zero. When the pulsating DC voltage is zero, it means that the fan has left the headwind state, and the soft start voltage is stopped from being input to the fan. At this time, the rated voltage is input to the fan. Since the fan is in a normal stationary state, there will be no armature reaction or high voltage DC pulse, and it can work normally.

[0067] S108: Generates a discharge signal and turns on the discharge circuit;

[0068] Specifically, the discharge signal controls a relay to activate the discharge circuit, releasing the high-voltage DC pulse; (Reference) Figure 2The discharge circuit diagram shows that the discharge circuit consists of a varistor 202 and a discharge tube 201 connected in parallel. One end of the parallel circuit is coupled to the fan, and the other end is directly grounded. The high-voltage DC pulse generated by the fan's reversing torque is first released to ground through the varistor 202. Since the continuous action of a large current on the varistor 202 will cause its performance to degrade, after the varistor 202 has been discharging for a period of time, the discharge tube 201 is turned on to shunt the current to the varistor 202, thereby shortening the time when the varistor 202 carries a large current and helping to slow down the performance degradation of the varistor 202.

[0069] S109: Input forward voltage to operate the fan normally;

[0070] Specifically, after the pulsating DC voltage caused by the fan reversing disappears, it indicates that the fan has left the headwind state. A forward rotation voltage is then input to the fan to enable normal operation. The forward rotation voltage includes a low-speed forward rotation voltage and a rated forward rotation voltage. When the pulsating DC voltage disappears, the fan blades are stationary. At this point, a low-speed forward rotation voltage is first supplied to the fan to drive it into low-speed mode. In the embodiments of this application, for a 380V high-power permanent magnet motor, the low-speed forward rotation voltage can be set to 220V, and the low-speed mode can last for 30 seconds. In low-speed mode, the fan speed is lower than the rated speed, thereby eliminating the residual effects of the fan starting against the wind during low-speed operation and allowing for slow preheating. After the fan has been running at low speed for a certain period, the rated operating voltage is input by adjusting the resistance value to bring the fan to its rated speed for normal operation.

[0071] The implementation principle of the fan reverse-wind start method in this application embodiment is as follows: The reverse electromotive force generated by the fan due to reverse rotation is rectified by a diode into a pulsating DC voltage. The pulsating DC voltage is detected to be within a set threshold. If it is, a soft-start voltage is input to the fan via the controller. This soft-start voltage acts on the fan to generate a torque that prevents the fan from reversing. This torque prevents the fan from reversing, causing the fan blades to stop reversing and return to a stationary state. Once the fan is out of the reverse-wind state, a low-speed forward voltage is input to the fan, allowing it to operate in a low-speed mode. After a period of time, a rated forward voltage is input to the fan, enabling it to operate normally. This fan reverse-wind start method achieves normal start-up of the fan under reverse-wind conditions with minimal damage to the fan's internal structure.

[0072] In another embodiment of this application, a method for starting a wind turbine against the wind further includes the following steps after obtaining the pulsating DC voltage:

[0073] The control signal for the louver mechanism is generated based on the voltage value of the pulsating DC voltage and the corresponding proportional coefficient.

[0074] The opening angle of the electric louver mechanism is adjusted according to the control signal of the louver mechanism.

[0075] Specifically, in work scenarios such as farms, the air outlet of a fan is equipped with a louver mechanism to control the airflow. This louver mechanism includes multiple louver blades connected to a control rod. The control rod controls the opening angle of the louver blades, thereby controlling the gap between two louver blades. The louver mechanism in this application is specifically an electric louver mechanism, and the control signal input from the intelligent terminal controls the opening angle of the louver blades. When the pulsating DC voltage generated by the fan due to headwind exceeds a set threshold, it indicates that the fan is in a strong headwind state. At this time, the louver mechanism should be adjusted to fully close. When the louver blades are at zero angle to the control lever, it indicates that the fan has broken free from the headwind and is ready for normal startup. At this time, the louver mechanism should be fully opened, with the louver blades at 90° angle to the control lever. When the pulsating DC voltage is between the allowable threshold and zero, the corresponding opening angle of the louver mechanism is calculated according to the different headwind conditions. The pulsating DC voltage and the opening angle of the louver blades are directly proportional. For example, if the pulsating DC voltage threshold is set to 400V, the louver blades reach the maximum opening angle of 90°. When the pulsating DC voltage is 200V, the louver blades open to 45°.

[0076] This application also discloses a wind turbine reverse-wind start-up system. (Refer to...) Figure 3 A wind turbine reverse-wind start-up system includes the following modules:

[0077] The fan start signal receiving module 301 is used to receive the fan start signal;

[0078] The pulsating DC voltage acquisition module 302 is used to acquire pulsating DC voltage;

[0079] The pulsating DC voltage judgment module 303 is used to determine whether the pulsating DC voltage is less than a set threshold.

[0080] The soft-start voltage generation module 304 is used to generate a soft-start voltage according to the pulsed DC voltage controller.

[0081] The forward rotation voltage generation module 305 is used to input the forward rotation voltage according to the fan start signal;

[0082] Alarm signal generation module 306 is used to generate alarm signals;

[0083] The discharge signal generation module 307 is used to generate a discharge signal.

[0084] This application also discloses a computer device.

[0085] Please see Figure 4 This is a schematic diagram of the structure of an electronic device 400 provided in an embodiment of this application. Figure 4 As shown, the electronic device 400 may include: at least one processor 401, at least one network interface 404, user interface 403, memory 405, and at least one communication bus 402.

[0086] The communication bus 402 is used to enable communication between these components.

[0087] The user interface 403 may include a display screen and a camera. Optionally, the user interface 403 may also include a standard wired interface and a wireless interface.

[0088] The network interface 404 may optionally include a standard wired interface or a wireless interface (such as a Wi-Fi interface).

[0089] The processor 401 may include one or more processing cores. The processor 401 connects to various parts of the server using various interfaces and lines, and performs various server functions and processes data by running or executing instructions, programs, code sets, or instruction sets stored in memory 405, and by calling data stored in memory 405. Optionally, the processor 401 may be implemented using at least one hardware form of Digital Signal Processing (DSP), Field-Programmable Gate Array (FPGA), or Programmable Logic Array (PLA). The processor 401 may integrate one or a combination of several of the following: Central Processing Unit (CPU), Graphics Processing Unit (GPU), and modem. The CPU primarily handles the operating system, user interface, and applications; the GPU is responsible for rendering and drawing the content required for display; and the modem handles wireless communication. It is understood that the modem may also be implemented as a separate chip without being integrated into the processor 401.

[0090] The memory 405 may include random access memory (RAM) or read-only memory. Optionally, the memory 405 may include non-transitory computer-readable storage medium. The memory 405 can be used to store instructions, programs, code, code sets, or instruction sets. The memory 405 may include a program storage area and a data storage area, wherein the program storage area may store instructions for implementing an operating system, instructions for at least one function (such as touch function, sound playback function, image playback function, etc.), instructions for implementing the above-described method embodiments, etc.; the data storage area may store data involved in the above-described method embodiments, etc. Optionally, the memory 405 may also be at least one storage device located remotely from the aforementioned processor 401. Figure 4 As shown, the memory 405, which serves as a computer storage medium, may include an operating system, a network communication module, a user interface 403 module, and an application program for a wind turbine reverse-wind start-up method.

[0091] exist Figure 4 In the electronic device 400 shown, the user interface 403 is mainly used to provide an input interface for the user and to obtain the user input data; while the processor 401 can be used to call an application program of a wind turbine reverse wind start method stored in the memory 405. When executed by one or more processors 401, the electronic device 400 performs one or more of the methods described in the above embodiments.

[0092] An electronic device 400-readable storage medium stores instructions. When executed by one or more processors 401, the electronic device 400 performs one or more methods as described in the above embodiments.

[0093] This application also discloses a computer-readable storage medium.

[0094] Specifically, the computer-readable storage medium stores a computer program that can be loaded by the processor 401 and executed as described above for a fan starting method against the wind. The computer-readable storage medium includes, for example, various media capable of storing program code, such as a USB flash drive, a portable hard drive, a read-only memory 405 (ROM), a random access memory 405 (RAM), a magnetic disk, or an optical disk.

[0095] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A method for starting a fan against the wind, characterized in that, The method includes the following steps: Receive the fan start signal; A pulsating DC voltage is obtained, which is generated by the reverse electromotive force generated by the fan reversing and passed through a diode installed inside the fan; The control signal for the louver mechanism located at the air outlet of the fan is generated based on the voltage value of the pulsating DC voltage and the corresponding proportional coefficient. The opening angle of the louver mechanism is adjusted according to the control signal of the louver mechanism; When the pulsating DC voltage exceeds the set threshold, the louver mechanism will fully close. When the pulsating DC voltage is zero, the louver mechanism is fully open. When the pulsating DC voltage is between the allowable threshold and zero, there is a proportional relationship between the pulsating DC voltage and the opening angle of the louver blades; determine whether the pulsating DC voltage is less than the set threshold; If so, a soft-start voltage is generated according to the pulsed DC voltage control controller, wherein the maximum value of the soft-start voltage is less than or equal to the pulsed DC voltage, and the direction is opposite to that of the pulsed DC voltage; The soft-start voltage is applied to the fan to generate a torque that prevents the fan from reversing, until the voltage value of the pulsating DC voltage is zero. When the voltage value of the pulsating DC voltage is zero, the forward voltage is input to operate the fan normally.

2. The method for starting a fan against the wind according to claim 1, characterized in that, After determining whether the pulsating DC voltage is less than a set threshold, the following steps are also included: If the pulsating DC voltage is greater than or equal to the set threshold, the fan will be prevented from starting.

3. A method for starting a fan against the wind according to claim 2, characterized in that, After the step of preventing the fan from starting if the pulsating DC voltage is greater than or equal to the set threshold, the following steps are also included: An alarm signal is generated to control the alarm circuit to trigger an alarm, indicating that the fan is in an abnormal state.

4. A method for starting a fan against the wind according to claim 1, characterized in that: The waveform of the soft-start voltage is a periodic rectangular wave. The duty cycle of the soft-start voltage is adjusted based on the pulsating DC voltage and the preset adjustment rules to make the pulsating DC voltage decrease smoothly.

5. A method for starting a fan against the wind according to claim 1, characterized in that, After the step of generating the soft-start voltage according to the pulsed DC voltage control controller, the following steps are also included: A discharge signal is generated and a preset discharge circuit is activated, the discharge circuit being used to release the high-voltage DC pulse generated by the anti-fan reverse torque acting on the fan.

6. A method for starting a fan against the wind according to claim 5, characterized in that: The discharge circuit includes a varistor (202) and a discharge tube (201). The varistor (202) and the discharge tube (201) are connected in parallel. One end of the parallel circuit is coupled to the fan, and the other end is grounded.

7. A method for starting a fan against the wind according to claim 1, characterized in that, The steps for inputting forward voltage to operate the fan normally also include the following: After inputting the low-speed forward voltage in the first time period, the rated forward voltage is input, where the rated forward voltage is greater than the low-speed forward voltage.

8. A wind turbine reverse-wind start-up system, employing the wind turbine reverse-wind start-up method according to any one of claims 1-7, the system comprising the following modules: The fan start signal receiving module (301) is used to receive the fan start signal; A pulsating DC voltage acquisition module (302) is used to acquire pulsating DC voltage; The pulsating DC voltage judgment module (303) determines whether the pulsating DC voltage is less than a set threshold. A soft-start voltage generation module (304) is used to generate a soft-start voltage according to the pulsed DC voltage control controller; A forward rotation voltage generation module (305) is used to input a forward rotation voltage according to the fan start signal; An alarm signal generation module (306) is used to generate alarm signals; The discharge signal generation module (307) is used to generate a discharge signal.

9. A computer device, characterized in that, It includes a memory (405) and a processor (401), wherein the memory (405) stores a computer program that can be loaded by the processor (401) and executed according to any one of the methods of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The computer program is stored that can be loaded by the processor (401) and executed according to any one of the methods of claims 1 to 7.

Images