Wind turbine generator blade deicing and lightning protection device and method

Abstract

The invention discloses a wind turbine generator blade deicing and lightning protection device and method, and belongs to the technical field of wind turbine lightning protection, the device comprises a voltage doubling rectifier, a capacitor and a main power line which are connected in sequence, and further comprises a plurality of heating units embedded in the surface of a blade, and each heating unit is connected with the main power line through a branch power line. The main power line is further connected with a galvanometer used for detecting thundercloud charges, the output end of the galvanometer is connected with the voltage-doubler rectifier through a control unit, and the control unit is used for controlling positive and negative electrode switching of direct-current voltage output by the voltage-doubler rectifier according to the detection result of the galvanometer, so that charges carried by the heating units are the same as the thundercloud charges. According to the device, active lightning protection can be achieved while the blade is deiced.

Description

Technical Field

[0001] The present invention belongs to the technical field of wind turbine lightning protection, and in particular relates to a wind turbine blade deicing and lightning protection device and method. Background Art

[0002] In recent years, wind turbines have been widely deployed in areas with more complex terrain and harsher environments, such as plateaus, coastal areas, and offshore locations. These wind turbines are installed outdoors. High-tower turbines have hub-center heights exceeding 170 meters, and their rotors have rotational diameters exceeding 200 meters. This makes them highly susceptible to lightning strikes and direct targets for lightning strikes. Lightning is extremely destructive, and the immense energy released by a lightning strike can cause damage to turbine blades, generator insulation breakdown, and the burning of control components, resulting in significant direct and indirect economic losses for wind farms.

[0003] The lightning protection design of wind turbines is directly related to whether the wind turbines can work normally during thunderstorms. How to ensure the rationality and comprehensiveness of the lightning protection structure of wind turbines is crucial to ensuring the safety of wind turbines.

[0004] Chinese patent publication number CN107882697A discloses a wind turbine blade anti-icing and de-icing system, which protects the blades from lightning through a lightning protection layer. Chinese patent publication number CN117432595A discloses a wind turbine lightning conductor monitoring method, which detects the electrical signal through a detector and compares it with a preset threshold to determine whether the wind turbine lightning conductor is broken. Both are passive lightning protection methods with limited protection range. They cannot avoid lightning strikes and can only reduce the damage caused by lightning strikes. Summary of the Invention

[0005] The object of the present invention is to provide a wind turbine blade deicing and lightning protection device and method, which can realize active lightning protection while deicing the blades.

[0006] In order to achieve the above object, the present invention provides the following technical solutions: In the first aspect, the present invention provides a wind turbine blade de-icing and lightning protection device, comprising a voltage-doubling rectifier, a capacitor and a main power line connected in sequence, and also comprising a plurality of heating units embedded in the surface of the blade, each heating unit being connected to the main power line via a branch power line, and a galvanometer for detecting the charge of a thundercloud being also connected to the main power line, and the output end of the galvanometer is connected to the voltage-doubling rectifier via a control unit, and the control unit is used to control the positive and negative pole switching of the output DC voltage of the voltage-doubling rectifier according to the detection result of the galvanometer, so that the charge carried by each heating unit is the same as the charge of the thundercloud.

[0007] In combination with the first aspect, further, each heating unit is embedded in the pressure surface and the suction surface of the blade respectively, and each heating unit is insulated from the blade.

[0008] In combination with the first aspect, further, the surface curvature of each heating unit is consistent with the surface curvature of the blade.

[0009] In combination with the first aspect, further, the main power line and each branch power line are buried in the blade, each heating unit is electrically connected to each branch power line through a conductive connecting piece, and each conductive connecting piece is insulated from the blade.

[0010] In combination with the first aspect, further, the cables of the main power line and each branch power line are all made of highly flexible stranded wires.

[0011] In combination with the first aspect, further, the control unit includes: A controller, configured to output a control signal according to a detection result of the galvanometer; The switching element is used to control the positive and negative switching of the DC voltage output by the voltage doubler rectifier according to the control signal.

[0012] In combination with the first aspect, further, the controller adopts a microcontroller, an analog circuit controller, a digital logic circuit, a programmable logic controller or a dedicated integrated circuit; the switching element adopts a relay, a metal-oxide semiconductor field effect transistor or an insulated gate bipolar transistor.

[0013] In combination with the first aspect, further, the control unit further includes: A signal conditioning module, used to perform one or more combinations of signal amplification, filtering and noise removal, level conversion and isolation, and analog-to-digital conversion on the detection results of the galvanometer; The protection module is used to provide one or more combinations of overvoltage protection, overcurrent protection, and temperature protection to the control unit.

[0014] In combination with the first aspect, further, signal amplification uses an operational amplifier or an instrumentation amplifier, filtering and denoising uses a low-pass filter or a band-pass filter, level conversion and isolation use a level conversion chip, an optocoupler isolator or an isolation amplifier, and analog-to-digital conversion uses an analog-to-digital converter; overvoltage protection uses a transient voltage suppression diode or an RC buffer circuit, overcurrent protection uses a fuse or a current limiting circuit, and temperature protection uses a temperature sensor or a thermal relay.

[0015] In a second aspect, the present invention provides a method for de-icing and lightning protection of wind turbine blades, which uses a wind turbine blade de-icing and lightning protection device as described in any one of the first aspects to de-ice and protect the wind turbine blades. A DC voltage is output through a voltage doubler rectifier to power each heating unit, so that each heating unit is heated to de-ice the blades; and a galvanometer is used to detect the charge of the thundercloud. The control unit controls the positive and negative pole switching of the DC voltage output by the voltage doubler rectifier according to the detection result of the galvanometer, so that the charge carried by each heating unit is the same as the charge of the thundercloud, thereby actively protecting the blades from lightning.

[0016] Compared with the prior art, the present invention has the following beneficial effects: The wind turbine blade deicing and lightning protection device provided by the present invention outputs a DC voltage through a voltage-doubling rectifier to power each heating unit, thereby heating each heating unit and de-icing the blades; a galvanometer is used to detect the charge of the thundercloud, and a control unit controls the positive and negative pole switching of the DC voltage output by the voltage-doubling rectifier according to the detection result of the galvanometer, so that the charge carried by each heating unit is the same as the charge of the thundercloud, thereby actively protecting the blades from lightning; and active lightning protection can be achieved while de-icing the blades. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic structural diagram of a wind turbine blade deicing and lightning protection device provided by an embodiment of the present invention; In the figure: 1. Heating unit; 2. Main power line; 3. Branch power line; 4. Voltage doubler rectifier; 5. Capacitor; 6. Ammeter; 7. Control unit. DETAILED DESCRIPTION

[0018] The technical solution of the present application will be further described in detail below in conjunction with specific implementation methods.

[0019] The embodiments of the present application are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application and are not to be construed as limiting the present application. The embodiments of the present application and the technical features in the embodiments may be combined with each other unless there is a conflict.

[0020] The embodiment of the present application provides a wind turbine blade deicing and lightning protection device, such as Figure 1 As shown, it includes a voltage doubler rectifier 4, a capacitor 5 and a main power line 2 connected in sequence, and also includes several heating units 1 embedded in the surface of the blade.

[0021] In this embodiment, each heating unit 1 is connected to the main power line 2 through a branch power line 3. The main power line 2 is also connected to a galvanometer 6 for detecting the charge of the thundercloud. The output end of the galvanometer 6 is connected to the voltage doubler rectifier 4 through a control unit 7. The control unit 7 is used to control the positive and negative pole switching of the DC voltage output by the voltage doubler rectifier 4 according to the detection result of the galvanometer 6, so that the charge carried by each heating unit 1 is the same as the charge of the thundercloud.

[0022] In this embodiment, on the one hand, a DC voltage is outputted by the voltage-doubling rectifier 4 to supply power to each heating unit 1, so that each heating unit 1 is heated and the blades are de-iced; on the other hand, the thundercloud charge is detected by the galvanometer 6, and the control unit 7 controls the positive and negative pole switching of the DC voltage output by the voltage-doubling rectifier 4 according to the detection result of the galvanometer 6, so that the charge carried by each heating unit 1 is the same as the thundercloud charge, thereby actively protecting the blades from lightning; active lightning protection can be achieved while de-icing the blades.

[0023] Specifically, the voltage doubler rectifier 4 inputs AC voltage and outputs DC voltage. The output end of the voltage doubler rectifier 4 is connected to the first plate of the capacitor 5, the second plate of the capacitor 5 is connected to the main power line 2, each heating unit 1 is connected to the main power line 2 through a branch power line 3, the ammeter 6 is connected to the main power line 2, and the output end of the ammeter 6 is connected to the voltage doubler rectifier 4 through the control unit 7.

[0024] When the galvanometer 6 detects that the charge of the thundercloud is positive, the control unit 7 controls the voltage doubler rectifier 4 to output the DC voltage to the negative pole, so that the first plate of the capacitor 5 is negatively charged and the second plate of the capacitor 5 is positively charged, thereby making each heating unit 1 positively charged, that is, the charge carried by each heating unit 1 and the charge of the lightning element are of the same charge and repel each other, thereby realizing active lightning protection.

[0025] When the galvanometer 6 detects that the charge of the thundercloud is negative, the control unit 7 controls the voltage doubler rectifier 4 to output the DC voltage to the positive pole, so that the first plate of the capacitor 5 is positively charged and the second plate of the capacitor 5 is negatively charged, thereby making each heating unit 1 negatively charged, that is, the charge carried by each heating unit 1 and the charge of the lightning element are of the same charge and repel each other, thereby realizing active lightning protection.

[0026] In a possible embodiment, each heating unit 1 is respectively embedded in the pressure surface and the suction surface of the blade, and each heating unit 1 is insulated from the blade.

[0027] In this embodiment, the heating units 1 are arranged and distributed along the length direction of the blade. One side of the heating unit 1 is embedded in the surface of the blade and is insulated from the blade. The other side of the heating unit 1 is exposed to the outside and is used to release positive or negative charges.

[0028] Specifically, each heating unit 1 is fixed to the blade by an insulating screw, and can adapt to various stresses and deformations generated when the blade is working without falling off from the blade.

[0029] In a possible embodiment, the surface curvature of each heating unit 1 is consistent with the surface curvature of the blade.

[0030] Specifically, the surface curvature of each heating unit 1 embedded in the pressure surface of the blade is consistent with the curvature of the pressure surface of the blade, and the surface curvature of each heating unit 1 embedded in the suction surface of the blade is consistent with the curvature of the suction surface of the blade, so that each heating unit 1 does not affect the normal operation of the blade.

[0031] In a possible embodiment, the main power line 2 and each branch power line 3 are buried in the blade, each heating unit 1 is electrically connected to each branch power line 3 through a conductive connecting piece, and each conductive connecting piece is insulated from the blade.

[0032] In this embodiment, the blades are provided with cavities for burying the main power line 2 and the branch power lines 3. These lines are tightly embedded within the blade cavities, making them less susceptible to movement or deformation during blade operation. The main power line 2 and the branch power lines 3 are also insulated from the blades.

[0033] Specifically, the cables of the main power line 2 and each branch power line 3 are made of highly flexible stranded wires, which can adapt to various stresses and deformations generated when the blades are working, and are not easy to move or deform, and are even less likely to break.

[0034] In a possible embodiment, the main power line 2 and each branch power line 3 can be fastened to the cavity in the blade by means of spaced-apart clips, further preventing the main power line 2 and each branch power line 3 from moving or deforming when the blade is working.

[0035] In a possible embodiment, the control unit 7 includes: A controller, configured to output a control signal according to the detection result of the galvanometer 6; The switch element is used to control the positive and negative switching of the DC voltage output by the voltage doubler rectifier 4 according to the control signal.

[0036] In this embodiment, the controller is a microcontroller, an analog circuit controller, a digital logic circuit, a programmable logic controller or a dedicated integrated circuit; the switch element is a relay, a metal-oxide semiconductor field effect transistor or an insulated gate bipolar transistor.

[0037] Specifically, the microcontroller (MCU) implements logic control through programming, processes analog or digital signals from the galvanometer 6, and outputs control signals to drive the switching elements. The MCU is highly flexible and can be programmed to implement complex logic (such as adaptive thresholds, delayed switching, and debounce). It supports multitasking and can integrate other functions (such as data logging and communication interfaces).

[0038] Analog circuit controllers use operational amplifiers, comparators, and triggers to build hardware logic. Window comparators detect changes in current direction (e.g., triggering between positive and negative thresholds). Monostable triggers generate switching pulses of fixed duration. Analog circuit controllers offer fast response times, simple circuitry, and low cost. They require no programming and are suitable for deterministic logic.

[0039] Digital logic circuits use logic gates, counters, shift registers, and other components to implement state machine control. They are highly deterministic and robust against interference. They are of moderate complexity and are suitable for medium-scale logic.

[0040] Programmable Logic Controllers (PLCs) implement industrial-grade control logic through ladder diagram programming. PLCs offer high reliability and strong anti-interference capabilities, making them easy to integrate into industrial automation systems.

[0041] Application-Specific Integrated Circuits (ASICs / modules) use custom or off-the-shelf control modules to integrate signal conditioning, logic processing, and drive functions. ASICs / modules are highly integrated and simplify design.

[0042] The switching elements include relays (mechanical / solid-state), metal-oxide semiconductor field-effect transistors (MOSFETs), and gate-integrated bipolar transistors (IGBTs), and require a drive circuit (such as optocoupler isolation).

[0043] In a possible embodiment, the control unit 7 further includes: A signal conditioning module, configured to perform one or more combinations of signal amplification, filtering and noise reduction, level conversion and isolation, and analog-to-digital conversion on the detection results of the galvanometer 6; The protection module is used to perform one or more combinations of overvoltage protection, overcurrent protection, and temperature protection on the control unit 7.

[0044] In this embodiment, an operational amplifier or an instrumentation amplifier is used for signal amplification, a low-pass filter or a band-pass filter is used for filtering and noise removal, a level conversion chip, an optocoupler isolator or an isolation amplifier is used for level conversion and isolation, and an analog-to-digital converter is used for analog-to-digital conversion; a transient voltage suppression diode or an RC buffer circuit is used for overvoltage protection, a fuse or a current limiting circuit is used for overcurrent protection, and a temperature sensor or a thermal relay is used for temperature protection.

[0045] Specifically, the signal conditioning module processes the original signal output by the galvanometer 6 to meet the input requirements of the controller. The main functions include: (1) Signal amplification: Function: The signal output by galvanometer 6 may be relatively weak and needs to be amplified to a range that can be recognized by the controller.

[0046] Implementation: Using an operational amplifier or instrumentation amplifier.

[0047] (2) Filtering and denoising: Function: Eliminate high-frequency interference (such as switching noise, electromagnetic interference) or low-frequency drift.

[0048] Implementation: 1. Low-pass filtering: Filter out high-frequency noise (RC circuit, active filter).

[0049] 2. Bandpass filtering: retains signals in a specific frequency band.

[0050] For example: RC low-pass filter circuit can suppress the spike interference generated by MOSFET switching.

[0051] (3) Level conversion and isolation: effect: 1. Adjust the signal to a level compatible with the controller.

[0052] 2. Isolate the high-voltage side and low-voltage side circuits to avoid common ground interference or damage to the controller.

[0053] Implementation: 1. Level conversion chip.

[0054] 2. Optocoupler isolation.

[0055] 3. Isolation amplifier.

[0056] (4) Analog-to-digital conversion (ADC): Function: Convert analog signals (such as current direction and amplitude) into digital signals for MCU processing.

[0057] Implementation method: MCU with built-in ADC or external ADC chip.

[0058] The protection module is used to prevent the system from being damaged due to abnormal voltage / current, excessive temperature, etc., ensuring long-term reliable operation. The main functions include: (1) Overvoltage protection: Function: Prevent voltage spikes or surges from breaking down devices (such as MOSFET, IGBT).

[0059] Implementation: 1. Transient Voltage Suppressor Diode (TVS): Quickly absorbs transient high voltage.

[0060] 2. RC snubber circuit: suppresses switching transients (such as a resistor in series with the MOSFET gate and a capacitor in parallel).

[0061] 3. Zener: clamps the voltage to a safe range.

[0062] (2) Overcurrent protection: Function: Prevent the current from exceeding the rated value of the device and causing it to burn out.

[0063] Implementation: 1. Fuse / Resettable Fuse: Physically cuts off excessive current.

[0064] 2. Current detection + shutdown: The current is detected by the Hall sensor, triggering the MCU or comparator to shut down the drive signal.

[0065] 3. Current limiting circuit: Use a constant current source or MOSFET current limiting design.

[0066] (3) Temperature protection: Function: Prevent power devices (such as IGBT) from failing due to overheating.

[0067] Implementation: 1. The temperature sensor cooperates with the MCU to trigger frequency reduction or shutdown.

[0068] 2. Thermal relay: A mechanical temperature switch that directly cuts off the circuit.

[0069] (4) Anti-reverse polarity and anti-static (ESD): effect: 1. Anti-reverse connection: Avoid reverse polarity of power supply to avoid damaging the circuit.

[0070] 2. Anti-static: Protect sensitive devices (such as MCU) from damage by electrostatic discharge.

[0071] Implementation: 1. Diode reverse connection protection: Connect a diode in series or use a MOSFET reverse polarity protection circuit.

[0072] 2. Electrostatic discharge protection device (ESD): TVS array or ESD suppressor.

[0073] (5) Isolation and redundancy design: effect: 1. Electrical isolation: Block ground loop interference or high voltage conduction (optocoupler, isolated power supply).

[0074] 2. Redundant design: Critical path backup (such as dual relays in parallel) improves fault tolerance.

[0075] This embodiment provides an applicable scenario for 4-polarity switching control of a voltage doubler rectifier: Signal conditioning module: galvanometer 6 outputs differential signal → instrumentation amplifier amplifies → low-pass filter removes noise → optocoupler isolates → MCU ADC samples.

[0076] Ensure that the MCU accurately determines the direction of current and triggers polarity switching.

[0077] Protection module: Overvoltage protection: A TVS tube is connected in parallel to the DS pole of the MOSFET to absorb the voltage spike when the voltage doubler rectifier is switched.

[0078] Overcurrent protection: The Hall sensor monitors the load current in real time, and the MCU shuts off the drive signal when the current exceeds the threshold.

[0079] Temperature protection: NTC is installed on the IGBT heat sink, and the fan is triggered or the load is reduced when the temperature exceeds the limit.

[0080] The signal conditioning module "cleans" and "adapts" the original signal to ensure that the control logic is based on accurate and stable input.

[0081] The protection module builds a "safety net" for the system to prevent abnormal operating conditions from causing permanent damage.

[0082] The combination of the two is the core design link to ensure system accuracy, response speed and long-term reliability.

[0083] An embodiment of the present application also provides a method for de-icing and lightning protection of wind turbine blades, which uses a wind turbine blade de-icing and lightning protection device as provided in any embodiment of the present application to de-ice and protect the wind turbine blades from lightning. A DC voltage is output through a voltage doubler rectifier 4 to power each heating unit 1, so that each heating unit 1 is heated to de-ice the blades; and a galvanometer 6 is used to detect the charge of the thundercloud. The control unit 7 controls the positive and negative pole switching of the DC voltage output by the voltage doubler rectifier 4 according to the detection result of the galvanometer 6, so that the charge carried by each heating unit 1 is the same as the charge of the thundercloud, thereby actively protecting the blades from lightning.

[0084] Specifically, when the galvanometer 6 detects that the charge of the thundercloud is positive, the control unit 7 controls the voltage doubler rectifier 4 to output the DC voltage to the negative pole, so that the first plate of the capacitor 5 is negatively charged and the second plate of the capacitor 5 is positively charged, thereby making each heating unit 1 positively charged, that is, the charge carried by each heating unit 1 and the charge of the lightning element are of the same charge and repel each other, thereby realizing active lightning protection.

[0085] When the galvanometer 6 detects that the charge of the thundercloud is negative, the control unit 7 controls the voltage doubler rectifier 4 to output the DC voltage to the positive pole, so that the first plate of the capacitor 5 is positively charged and the second plate of the capacitor 5 is negatively charged, thereby making each heating unit 1 negatively charged, that is, the charge carried by each heating unit 1 and the charge of the lightning element are of the same charge and repel each other, thereby realizing active lightning protection.

[0086] The wind turbine blade deicing and lightning protection method provided in the embodiment of the present application has the corresponding beneficial effects of the wind turbine blade deicing and lightning protection device.

[0087] The above is only a preferred embodiment of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A wind turbine blade deicing and lightning protection device, characterized in that: The invention comprises a voltage-doubling rectifier (4), a capacitor (5) and a main power line (2) connected in sequence, and also comprises a plurality of heating units (1) embedded in the surface of the blade, wherein each heating unit (1) is connected to the main power line (2) via a branch power line (3), and the main power line (2) is also connected to a galvanometer (6) for detecting the charge of the thundercloud, and the output end of the galvanometer (6) is connected to the voltage-doubling rectifier (4) via a control unit (7), and the control unit (7) is used to control the switching of the positive and negative poles of the DC voltage output by the voltage-doubling rectifier (4) according to the detection result of the galvanometer (6), so that the charge carried by each heating unit (1) is the same as the charge of the thundercloud.

2. The wind turbine blade deicing and lightning protection device according to claim 1, characterized in that: Each heating unit (1) is respectively embedded in the pressure surface and the suction surface of the blade, and each heating unit (1) is insulated and connected to the blade.

3. The wind turbine blade deicing and lightning protection device according to claim 1, characterized in that: The surface curvature of each heating unit (1) is consistent with the surface curvature of the blade.

4. The wind turbine blade deicing and lightning protection device according to claim 1, characterized in that: The main power line (2) and each branch power line (3) are embedded in the blades, each heating unit (1) is electrically connected to each branch power line (3) via a conductive connecting piece, and each conductive connecting piece is insulated from the blades.

5. The wind turbine blade deicing and lightning protection device according to claim 1, characterized in that: The main power line (2) and each branch power line (3) are both made of highly flexible stranded wire.

6. The wind turbine blade deicing and lightning protection device according to claim 1, characterized in that: The control unit (7) comprises: A controller, configured to output a control signal according to a detection result of the galvanometer (6); The switching element is used to control the switching between the positive and negative poles of the DC voltage output by the voltage doubler rectifier (4) according to the control signal.

7. The wind turbine blade deicing and lightning protection device according to claim 6, characterized in that: The controller adopts a microcontroller, an analog circuit controller, a digital logic circuit, a programmable logic controller or a dedicated integrated circuit; the switch element adopts a relay, a metal-oxide semiconductor field effect transistor or an insulated gate bipolar transistor.

8. The wind turbine blade deicing and lightning protection device according to claim 6, characterized in that: The control unit (7) further comprises: A signal conditioning module for performing one or more combinations of signal amplification, filtering and noise removal, level conversion and isolation, and analog-to-digital conversion on the detection result of the galvanometer (6); The protection module is used to perform one or more combinations of overvoltage protection, overcurrent protection, and temperature protection on the control unit (7).

9. The wind turbine blade deicing and lightning protection device according to claim 8, characterized in that: Signal amplification uses operational amplifiers or instrumentation amplifiers, filtering and noise removal use low-pass filters or band-pass filters, level conversion and isolation use level conversion chips, optocoupler isolators or isolation amplifiers, and analog-to-digital conversion uses analog-to-digital converters; overvoltage protection uses transient voltage suppression diodes or RC buffer circuits, overcurrent protection uses fuses or current limiting circuits, and temperature protection uses temperature sensors or thermal relays.

10. A wind turbine blade deicing and lightning protection method, characterized in that: The wind turbine blade deicing and lightning protection device according to any one of claims 1 to 9 is used to perform deicing and lightning protection on the wind turbine blades, wherein a DC voltage is outputted by a voltage doubler rectifier (4) to supply power to each heating unit (1), so that each heating unit (1) is heated and the blades are de-iced; and a galvanometer (6) is used to detect the thundercloud charge, and a control unit (7) controls the switching of the positive and negative poles of the DC voltage outputted by the voltage doubler rectifier (4) according to the detection result of the galvanometer (6), so that the charge carried by each heating unit (1) is the same as the thundercloud charge, thereby actively protecting the blades from lightning.

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