A method for cooperative operation of a wind power system with supercritical airfoil blade structure

Abstract

The present application relates to the technical field of electric energy storage systems, and proposes a wind power system cooperative operation method using supercritical airfoil blade structure for solving the problem of wind turbine blade vibration affecting the power grid's acceptance capacity of wind power, comprising a supercritical airfoil blade structure and a hierarchical cooperative control system; the supercritical airfoil blade structure comprises a blade body composed of a blade root part, a blade body part and a blade tip part, a sound attenuation and noise reduction sheet is fixedly arranged at the trailing edge of the blade body, the sound attenuation and noise reduction sheet is provided with a splicing groove, the trailing edge of the sound attenuation and noise reduction sheet is in a continuous curved line shape or a continuous broken line shape, and grooves are arranged on the surface of the sound attenuation and noise reduction sheet; a melamine foam vibration absorption layer is clamped at the trailing edge of the blade body, and a vibration absorption groove is arranged at the bottom of the splicing groove; a V-shaped opening for reducing wind resistance area is arranged at the blade tip part of the blade body; the hierarchical cooperative control system comprises a dynamic power distribution module and an angular frequency error feedback synchronous control module.

Description

A method for coordinated operation of wind power systems using supercritical airfoil blades Technical Field

[0001] This invention relates to the field of energy storage system technology, and in particular to a method for the coordinated operation of a wind power system using a supercritical airfoil blade structure. Background Technology

[0002] Supercritical airfoils are an advanced airfoil design, employing a special upper surface curvature and lower surface convexity design. They offer advantages such as low drag and good lift performance during high-speed flight and are widely used in wind turbine blades. Wind turbine blades are typically slender, hollow, thin-walled structures composed of three parts: the blade root, the blade body, and the blade tip. During operation, they must withstand alternating loads, and stress concentrations easily occur at the blade root, the connection between the web and the shell, and the transition area at the blade tip. Simultaneously, when the blade rotates at high speed, a large number of vortices are generated at the trailing edge. The shedding and collision of these vortices not only generate strong aerodynamic noise but can also trigger vortex-induced resonance, seriously affecting the structural safety and service life of the blade. The negative impacts of blade vibration are not limited to the blade itself and turbine operation but also extend to the power grid system. Blade vibration causes fluctuations in the turbine's output power, manifesting as instantaneous fluctuations in voltage and frequency, affecting the power quality of the grid. Especially in large-scale wind power grid-connected scenarios, excessive power fluctuations increase the difficulty of grid frequency and voltage regulation, restricting the grid's ability to accept wind power and hindering wind power absorption. Furthermore, severe vibrations can trigger unplanned shutdowns of wind turbines, leading to a sharp drop in power, increasing pressure on grid dispatching, raising the demand for grid reserve capacity, and affecting the stability and economy of grid operation. Therefore, reducing wind turbine blade vibration is not only crucial for ensuring blade structural safety and improving turbine operational reliability, but also an important support for optimizing wind power grid connection characteristics and ensuring the stable and efficient operation of the power grid system.

[0003] In summary, to address the dual technical challenges of blade noise, structural safety, and the stability and economy of wind-storage system collaborative operation, this paper proposes a collaborative operation method for wind power systems using supercritical airfoil blades that integrates blade structure optimization and system collaborative control strategies. Summary of the Invention

[0004] Therefore, in view of the above problems, this invention proposes a method for the coordinated operation of wind power systems using supercritical airfoil blades to solve the problem of blade vibration affecting the grid's ability to accept wind power.

[0005] To solve the above-mentioned technical problems, the solution adopted by the present invention is: a method for the coordinated operation of a wind power system using a supercritical airfoil blade structure, including a supercritical airfoil blade structure and a hierarchical coordinated control system;

[0006] The supercritical airfoil blade structure includes a blade body composed of a blade root, a blade body, and a blade tip. A noise-reducing plate is fixedly installed at the trailing edge of the blade body. The noise-reducing plate has a splicing groove formed from the leading edge inward. The upper wall of the splicing groove is attached to the upper surface of the blade body, and the lower wall of the splicing groove is attached to the lower surface of the blade body. The trailing edge of the noise-reducing plate is a continuous curve or a continuous zigzag line. Several grooves are formed on the upper and lower surfaces of the noise-reducing plate. A melamine foam vibration-absorbing layer is sandwiched between the upper and lower shells at the trailing edge of the blade body. A vibration-absorbing groove is formed at the bottom of the splicing groove extending towards the trailing edge of the noise-reducing plate. The melamine foam vibration-absorbing layer fills the vibration-absorbing groove. A V-shaped opening is formed at the blade tip of the blade body to reduce wind resistance area.

[0007] The hierarchical collaborative control system includes a dynamic power allocation module and an angular frequency error feedback synchronization control module.

[0008] The dynamic power allocation module is used to construct a dynamic power allocation strategy based on grid load, wind speed and SOC state of energy storage system. By adjusting the allocation ratio of wind power output power to energy storage system output power, the system can maintain the optimal ratio under different wind power and grid demand conditions.

[0009] The angular frequency error feedback synchronization control module is used to construct a grid-connected wind turbine angular frequency error feedback synchronization control strategy. By dynamically correcting the error between the wind power output and the energy storage system output, the output power is synchronized with the grid demand in real time.

[0010] A further improvement is that the dynamic power allocation module includes an energy storage system modeling unit, a wind turbine system modeling unit, and a hierarchical control structure unit;

[0011] The output power control formula for the energy storage system modeling unit is:

[0012] ;

[0013] in, Power control commands for energy storage systems. This is a reference value for controlling the output power of the energy storage system. This represents the current actual output power of the energy storage system. This refers to the regulation coefficient of the energy storage system.

[0014] The output power control formula for the wind turbine system modeling unit is:

[0015] ;

[0016] in, For wind power power control commands, This is a reference value for wind power output control. This represents the current actual output power of the wind power. This is the regulation coefficient for wind power;

[0017] The hierarchical control structure unit is divided into high-level control, middle-level control, and low-level control;

[0018] High-level control: Calculate the global power target, determine the total power demand of the power grid, and the global power control formula is:

[0019] ,in This is a total power control command;

[0020] Mid-level control: Based on grid load, wind speed, and the SOC state of the energy storage system, the total power demand is allocated to the wind turbine system and the energy storage system using a dynamically adjusted power allocation ratio formula. The allocation ratio formula is as follows:

[0021] ;

[0022] in, , These are the power control commands for the wind power and energy storage systems at the current time t, respectively. ;

[0023] Low-level control: Executes the power output of the wind turbine system and energy storage system, ensuring that the actual output matches the control commands.

[0024] A further improvement is made to the power allocation ratio. The calculation formula is:

[0025] ;

[0026] in, , , These are the weighted coefficients representing the impact of wind speed, grid load demand, and the SOC state of the energy storage system on the allocation coefficient. Let be the wind speed at the current time t. Let t be the current grid load demand. This represents the state of charge of the energy storage system at the current time t.

[0027] A further improvement is that the dynamic power allocation module also includes an energy storage recursive dynamic surface control unit, the input of which is the current available power of the energy storage system. The reference phase angle input from the energy storage system to the converter and system frequency deviation The output is the reference value for the output power control of the energy storage system. The specific control logic is as follows:

[0028] ;

[0029] in, The rate of change of the system frequency deviation To control the gain, For the Laplace operator, Let be the time constant of the power response of the energy storage system. The time constant of the energy storage charging process. It is a high-frequency time constant. It is a low-frequency time constant.

[0030] A further improvement is that the angular frequency error feedback synchronization control module adjusts the virtual angular frequency of the fan through a nonlinear angular frequency feedback control function, which is:

[0031] ;

[0032] in, To account for the virtual angular frequency deviation of the grid-connected wind turbines, The system angular frequency, To output virtual angular frequency for grid-connected wind turbines, , These are the adjustment parameters for the controller. This is a parameter used to adjust the system's sensitivity to errors.

[0033] A further improvement is that the average ratio of the thickness of the leaf root to the chord length is 25%-35%, the average ratio of the thickness of the leaf body to the chord length is 15%-25%, and the average ratio of the thickness of the leaf tip to the chord length is 8%-15%.

[0034] A further improvement is that the average ratio of the thickness of the leaf root to the chord length is 30%, the average ratio of the thickness of the leaf body to the chord length is 20%, and the average ratio of the thickness of the leaf tip to the chord length is 12%.

[0035] A further improvement is that the blade body is coated with at least one reflective coating.

[0036] By adopting the aforementioned technical solution, the beneficial effects of the present invention are:

[0037] 1. This invention, through the deep integration of blade structure optimization and system collaborative control, reduces the impact of vibration and noise on unit operation at the source, and solves the impact of power fluctuations on the power grid through precise regulation of the back-end control system, forming a dual guarantee of "structural optimization + control collaboration". This method not only improves the reliability, safety, and economy of the wind power system itself, but also improves the adaptability of wind power grid connection, providing an effective solution for the efficient absorption of large-scale wind power and the stable operation of the power grid, and has broad engineering application value and promotion prospects.

[0038] 2. When wind turbine blades rotate at high speed, air flows from the leading edge to the trailing edge, forming numerous vortices of varying sizes. The shedding and collision of these vortices generate strong aerodynamic noise, and the concentrated energy of the large-scale vortices is the primary cause of the high-intensity noise. In this case, the noise-reducing diaphragm on the trailing edge of the blade body has a continuous curved or zigzag shape, creating a serrated structure. The serrations divide the continuous trailing edge of the blade into multiple small protrusions, breaking the airflow into multiple streams. The originally concentrated large vortices are "broken" into countless small vortices. The energy of these small vortices is far lower than that of the large vortices, and their shedding frequency is more dispersed. The noise peak generated by the impact on the air is significantly reduced, as if the concentrated "large noise" has been broken down into dispersed and less perceptible "small noise." After the noise energy is broken down, the overall noise intensity is reduced by 10-15 dB, and the noise generated by the broken small vortices is mainly low-frequency, avoiding the 2000-5000Hz frequency range that is sensitive to the human ear. It is especially suitable for the high humidity, strong gusts and turbulent environment of offshore wind power, which can improve the aerodynamic stability of the blades under extreme wind conditions, reduce the probability of failure and extend the service life of the wind turbine.

[0039] 3. The blade tip is the region with the highest linear velocity and centrifugal force during blade rotation, reaching speeds of 100-200 km / h. It also bears alternating stress from turbulent impacts and gust loads. From a structural mechanics perspective, the bifurcated structure at the blade tip is equivalent to adding a "support branch," which disperses stress concentration at the tail end, preventing cracks or breakage under high-frequency vibration. Compared to a straight blade tip, the bifurcated structure has stronger fatigue resistance, making it particularly suitable for blades operating under alternating loads for extended periods. The bifurcated tail shape reduces the risk of flutter during blade rotation, preventing resonance damage caused by fluid excitation and improving operational safety. Simultaneously, the bifurcated blade tip also reduces wake noise.

[0040] 4. The vibration-absorbing layer is sandwiched between the upper and lower shells and fills the vibration-absorbing groove of the noise reduction plate. The vibration-absorbing layer can be pre-cut into a shape that matches the vibration-absorbing groove. After being directly embedded, the noise reduction plate blade shell is spliced ​​and cured. The process is simple and easy to implement, which helps to reduce production modification costs and improve production efficiency.

[0041] Melamine foam is lightweight and possesses a high sound absorption coefficient, enabling it to directly absorb mid-to-high frequency aerodynamic noise generated by airflow disturbances at the trailing edge of the blade, as well as secondary vibrations caused by aerodynamic noise. It also helps to weaken the formation intensity of large-scale vortices at the trailing edge, reducing noise peaks caused by vortex shedding. This achieves a synergistic effect of "vibration damping + direct sound absorption + aerodynamic noise reduction," significantly reducing the overall noise level during blade rotation and meeting the low-noise environmental protection requirements for wind power equipment.

[0042] 5. The dynamic power allocation module constructs an allocation strategy based on grid load, wind speed, and the SOC state of the energy storage system. It precisely quantifies the impact of each factor using weighted coefficients (wind speed 0.3, grid load 0.4, SOC state 0.3) to achieve the real-time optimal power ratio between wind power and energy storage. For example, under conditions of 10 m / s wind speed, 3200 kW grid load, and 50% SOC, it can intelligently allocate 76% of the power demand to the wind power system and 24% to the energy storage system, ensuring efficient adaptation to different wind power output and grid demand scenarios.

[0043] 6. The angular frequency error feedback synchronous control module dynamically adjusts the virtual angular frequency of the wind turbine through a nonlinear control function. Combined with adjustment parameters (α=0.8, β=1.2, λ=0.5), it optimizes the error response characteristics, stabilizing the system angular frequency fluctuation within ±0.1Hz and controlling the output power fluctuation amplitude below ±3%. This improvement effectively solves the power fluctuation problem caused by blade vibration, avoids the impact of instantaneous voltage and frequency fluctuations on the power grid's power quality, and reduces the difficulty of frequency and voltage regulation during large-scale wind power grid connection.

[0044] 7. By flexibly adjusting the energy storage system (adjustment coefficient 0.8) and coordinating with the wind power system (adjustment coefficient 0.9), the randomness and intermittency of wind power output can be mitigated, reducing the risk of sudden power drops caused by unplanned unit shutdowns. Simultaneously, the rapid response characteristics of the energy storage recursive dynamic surface control unit (power response time constant 0.2s) can promptly compensate for wind power output gaps or absorb excess energy, reducing grid reserve capacity requirements, enhancing the grid's ability to absorb wind power, and increasing wind power absorption rate by 15%.

[0045] 8. The dynamic power allocation strategy improves the charging and discharging efficiency of the energy storage system to 92%, reducing the ineffective losses of the energy storage system; at the same time, by maximizing the utilization rate of wind power output and combining precise power control to reduce the wind curtailment rate, the annual power generation of the wind farm increases by about 8%, significantly improving the operating economy and return on investment of the wind farm. Attached Figure Description

[0046] Figure 1 is a schematic diagram of the assembly structure of the supercritical airfoil blade for wind power according to an embodiment of the present invention.

[0047] Figure 2 is a schematic diagram of a partial structure of the blade root in a supercritical airfoil blade of wind power according to an embodiment of the present invention.

[0048] Figure 3 is a schematic diagram of the structure of the supercritical airfoil blade for wind power according to an embodiment of the present invention.

[0049] Figure 4 is a schematic diagram of the cross-sectional structure of the supercritical airfoil blade for wind power according to an embodiment of the present invention.

[0050] Figure 5 is a magnified view of the local structure at point A in Figure 4.

[0051] Reference numerals: blade body 10, blade root 101, blade body 102, blade tip 103, reflective coating 104, noise reduction sheet 11, splicing groove 12, groove 13, melamine foam vibration absorption layer 14, vibration absorption groove 15, V-shaped opening 16. Detailed Implementation

[0052] The present invention will now be further described in conjunction with the accompanying drawings and specific embodiments.

[0053] Referring to Figures 1 to 5, the embodiments of the present invention disclose a method for the coordinated operation of a wind power system using a supercritical airfoil blade structure, including a supercritical airfoil blade structure and a hierarchical coordinated control system.

[0054] The supercritical airfoil structure includes a blade body 10 composed of a blade root 101, a blade body 102, and a blade tip 103. The blade body 10 is coated with at least one reflective coating 104. A noise-reducing plate 11 is fixedly disposed at the trailing edge of the blade body 10. The noise-reducing plate 11 has a splicing groove 12 extending inward from its leading edge. The upper wall of the splicing groove 12 is attached to the upper surface of the blade body 10, and the lower wall is attached to the lower surface of the blade body 10. The trailing edge of the noise-reducing plate 11 is a continuous curve or a continuous zigzag line. Several grooves 13 are formed on the upper and lower surfaces of the noise-reducing plate 11. A melamine foam vibration-absorbing layer 14 is sandwiched between the upper and lower shells at the trailing edge of the blade body 10. A vibration-absorbing groove 15 extends from the bottom of the splicing groove 12 towards the trailing edge of the noise-reducing plate 11, and the melamine foam vibration-absorbing layer 14 fills the vibration-absorbing groove 15. The blade body 10 has a V-shaped opening 16 at its tip 103 to reduce wind resistance area. The average thickness-to-chord length ratio of the blade root 101 is 25%-35%, preferably 30%; the average thickness-to-chord length ratio of the blade body 102 is 15%-25%, preferably 20%; and the average thickness-to-chord length ratio of the blade tip 103 is 8%-15%, preferably 12%. The surface of the blade body 10 is coated with one or two reflective coatings 104. The bottom layer of the reflective coating 104 is an epoxy primer with a thickness of 80 μm, and the top layer of the reflective coating 104 is a polyvinyl fluoride reflective topcoat with a thickness of 50 μm. The reflective coating 104 can effectively scare away birds and reduce the harm to birds caused by the rotation of the blade.

[0055] Specific settings for blade structure parameters:

[0056] 1. The overall length of the blade body 10 is set to 65m, of which the length of the leaf root 101 is 8m, the length of the leaf body 102 is 45m, and the length of the leaf tip 103 is 12m. The average ratio of the thickness to the chord length of the leaf root 101 is preferably 30%, corresponding to a maximum chord length of 5.2m and a thickness of 1.56m for the leaf root 101; the average ratio of the thickness to the chord length of the leaf body 102 is 20%, with a chord length of 3.8m and a thickness of 0.76m in the middle section of the leaf body 102; the average ratio of the thickness to the chord length of the leaf tip 103 is 12%, with a chord length of 1.2m and a thickness of 0.144m for the leaf tip 103. The included angle of the V-shaped opening 16 at the blade tip 103 is set to 60°, the opening depth is 1.8m, and the opening width gradually decreases from the blade tip to the blade body 102 along the blade length direction. The opening width at the blade tip is 0.8m, gradually decreasing to 0.3m at the connecting end of the blade body 102. This V-shaped opening 16 reduces the wind resistance area.

[0057] 2. The noise reduction plate 11 is made of carbon fiber composite material, with an overall length consistent with the trailing edge length of the blade body 10 and a width of 0.6m. A splicing groove 12, 0.15m wide, is formed inwards from its leading edge. The upper wall of the splicing groove 12 is completely flush with the upper surface of the blade body 10, and the lower wall is completely flush with the lower surface of the blade body 10, fixed together by high-strength adhesive. The trailing edge of the noise reduction plate 11 adopts a continuous curved design with a radius of curvature of 1m. Several grooves 13 are formed on both the upper and lower surfaces of the noise reduction plate 11. The grooves 13 are U-shaped, 8cm wide, 12cm deep, and 25cm apart. The grooves 13 are evenly distributed along the length of the noise reduction plate 11. The melamine foam vibration-absorbing layer 14 sandwiched between the upper and lower shells at the trailing edge of the blade body 10 has a thickness of 50 mm, a density of 35 kg / m³, and an elastic modulus of 0.8 MPa. The vibration-absorbing groove 15 extending from the bottom of the splicing groove 12 toward the trailing edge of the noise-reducing plate 11 has a width of 0.1 m and a depth of 0.3 m. The melamine foam vibration-absorbing layer completely fills the vibration-absorbing groove 15 and is tightly fitted with the noise-reducing plate 11 and the trailing edge of the blade body 10.

[0058] The hierarchical collaborative control system includes a dynamic power allocation module and an angular frequency error feedback synchronization control module. The dynamic power allocation module is used to construct a dynamic power allocation strategy based on grid load, wind speed, and the SOC state of the energy storage system. By adjusting the power distribution ratio between wind power output and energy storage system output, the system maintains an optimal balance under different wind power and grid demand conditions. The dynamic power allocation module includes an energy storage system modeling unit, a wind turbine system modeling unit, and a hierarchical control structure unit. The angular frequency error feedback synchronization control module is used to construct a grid-connected wind turbine angular frequency error feedback synchronization control strategy. By dynamically correcting the error between wind power output and energy storage system output, the output power is synchronized with grid demand in real time.

[0059] The output power control formula for the energy storage system modeling unit is:

[0060] ;

[0061] in, Power control commands for energy storage systems. This is a reference value for controlling the output power of the energy storage system. This represents the current actual output power of the energy storage system. This refers to the regulation coefficient of the energy storage system.

[0062] The output power control formula for the wind turbine system modeling unit is:

[0063] ;

[0064] in, For wind power power control commands, This is a reference value for wind power output control. This represents the current actual output power of the wind power. This is the regulation coefficient for wind power;

[0065] The hierarchical control structure unit is divided into high-level control, middle-level control, and low-level control;

[0066] High-level control: Calculate the global power target, determine the total power demand of the power grid, and the global power control formula is:

[0067] ,in This is a total power control command;

[0068] Mid-level control: Based on grid load, wind speed, and the State of Charge (SOC) status of the energy storage system, the total power demand is allocated to the wind turbine system and the energy storage system using a dynamically adjusted power allocation ratio formula. The allocation ratio formula is as follows:

[0069] ;

[0070] in, , These are the power control commands for the wind power and energy storage systems at the current time t, respectively. ;

[0071] Low-level control: Executes the power output of the wind turbine system and energy storage system, ensuring that the actual output matches the control commands.

[0072] The power allocation ratio The calculation formula is:

[0073] ;

[0074] in, , , These are the weighted coefficients representing the impact of wind speed, grid load demand, and the SOC state of the energy storage system on the allocation coefficient. Let be the wind speed at the current time t. Let t be the current grid load demand. This represents the state of charge of the energy storage system at the current time t.

[0075] The dynamic power allocation module also includes an energy storage recursive dynamic surface control unit, whose input is the current available power of the energy storage system. The reference phase angle input from the energy storage system to the converter and system frequency deviation The output is the reference value for the output power control of the energy storage system. The specific control logic is as follows:

[0076] ;

[0077] in, The rate of change of the system frequency deviation To control the gain, For the Laplace operator, Let be the time constant of the power response of the energy storage system. The time constant of the energy storage charging process. It is a high-frequency time constant. It is a low-frequency time constant.

[0078] The angular frequency error feedback synchronization control module adjusts the virtual angular frequency of the fan through a nonlinear angular frequency feedback control function, which is:

[0079] ;

[0080] in, To account for the virtual angular frequency deviation of the grid-connected wind turbines, The system angular frequency, To output virtual angular frequency for grid-connected wind turbines, , These are the adjustment parameters for the controller. This is a parameter used to adjust the system's sensitivity to errors.

[0081] (a) Specific settings for system technical parameters

[0082] The wind turbine system has a rated power of 3.6MW and a maximum output power of 4.0MW. The energy storage system uses lithium batteries with a rated capacity of 2000kWh and a rated output power of 1000kW. The normal operating range of the energy storage system's State of Charge (SOC) is 20%-80%. When the SOC is below 20%, it enters a charging priority mode; when it is above 80%, it enters a discharging priority mode. Wind speed is measured using an ultrasonic anemometer with a measurement range of 0.5-25m / s and a measurement accuracy of ±0.1m / s. Grid load demand is obtained in real time through the grid dispatch center, with a data update frequency of once per second. The SOC of the energy storage system is monitored in real time by the battery management system (BMS) with a measurement accuracy of ±1%.

[0083] (II) Parameters and Operating Logic of Dynamic Power Allocation Module

[0084] 1. Adjustment coefficient setting: The adjustment coefficient of the energy storage system =0.8, the regulation coefficient of wind power =0.9; Weighting coefficient setting: (Weighted coefficient for wind speed influence) = 0.3 (Weighted coefficient for the impact of power grid load demand) = 0.4 (Weighted coefficient for the impact of SOC on energy storage system) = 0.3.

[0085] 2. Energy storage recursive dynamic surface control unit parameters: control gain =5.0, the time constant of the power response of the energy storage system =0.2s, the time constant of the energy storage charging process =2.5s, high-frequency time constant =0.05s, low-frequency time constant =3.0s.

[0086] 3. Operation process:

[0087] High-level control: Based on the total power demand issued by the power grid dispatch center. Combining the real-time operating status of the wind turbine system and the energy storage system, through the formula Calculate the global power target, where This is a wind power control command. This refers to power control commands for energy storage systems. For example, when the total power demand of the grid is 3500kW, the higher-level control decomposes this target to the middle-level control.

[0088] Mid-level control: based on the wind speed at the current time t. Power grid load demand and energy storage systems Through the power distribution ratio formula Calculate the distribution coefficient (Set the fan's rated wind speed to 2 m / s, the grid load corresponding to the fan's rated power to 3600 kW, SOC_min = 20%, SOC_max = 80%), then through , The total power demand is allocated to the wind turbine system and the energy storage system. Assume the wind speed at a certain time t... =10m / s, power grid load demand =3200kW, energy storage system =50%, then =0.3×(10 / 12)+0.4×(3200 / 3600)+0.3×(50%-20%) / (80%-20%)≈0.25+0.36+0.15=0.76, if the total power demand at this time =3500kW, then =0.76×3500=2660kW =(1-0.76)×3500=840kW.

[0089] Low-level control: The fan system is based on Adjusting the blade pitch angle and generator speed ensures the actual output power of the wind power. and The deviation shall not exceed ±5%; the energy storage system shall be based on Adjust the converter output to ensure the actual output power of the energy storage. and The deviation shall not exceed ±3%.

[0090] (III) Parameters and Operating Logic of Angular Frequency Error Feedback Synchronization Control Module

[0091] 1. Controller parameter settings: α=0.8, β=1.2, system error sensitivity adjustment parameter λ=0.5; system angular frequency. Set to 50Hz, with an allowable fluctuation range of ±0.2Hz.

[0092] 2. Operational Logic: Real-time acquisition of virtual angular frequency output from the grid-connected wind turbines. and system angular frequency Calculate angular frequency deviation Through nonlinear angular frequency feedback control function The virtual angular frequency of the wind turbine is dynamically adjusted. For example, when... At 0.3Hz, =0.8×tanh (-0.3)+1.2×0.3≈0.8×(-0.291)+0.36≈-0.233+0.36=0.127. Based on this control output, the power regulation command of the fan is adjusted, and the output power is corrected so that the output power is synchronized with the grid demand in real time, ensuring that the system angular frequency is stable within the set range.

[0093] (iv) Verification of implementation results

[0094] Under the specific parameter settings mentioned above, the collaborative operation method of the wind power system using a supercritical airfoil blade structure has been tested in an actual wind farm and has achieved the following results:

[0095] 1. Blade vibration suppression: The maximum vibration acceleration during blade operation is reduced from 0.8g in the traditional structure to 0.3g, and the vibration amplitude is reduced by 62.5%, which effectively reduces stress concentration and significantly reduces the risk of fatigue damage at the blade root, web-shell connection and blade tip transition zone.

[0096] 2. Noise control: The aerodynamic noise generated by the blade operation is reduced from 75dB(A) of the traditional structure to 62dB(A) at 100m, which meets the noise emission standards of wind farms.

[0097] 3. System operational stability: Under operating conditions with wind speed fluctuations of 3-18 m / s and grid load fluctuations of 2000-3800 kW, the system output power fluctuation amplitude is controlled within ±3%, and the system angular frequency fluctuation is stabilized within ±0.1 Hz, which significantly improves the stability of wind power grid connection and enhances the grid's ability to accept wind power.

[0098] 4. Economic efficiency: Through dynamic power allocation strategy, the charging and discharging efficiency of energy storage system is increased to 92%, wind power absorption rate is increased by 15%, and annual power generation of wind farm is increased by about 8%, which significantly improves the economic efficiency of wind farm operation.

[0099] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions above are merely illustrative of the principles of the present invention. Various changes and modifications can be made to the present invention without departing from its spirit and scope. All such changes and modifications fall within the scope of the present invention as claimed, which is defined by the appended claims and their equivalents.

Claims

1. A method for coordinated operation of a wind power system employing a supercritical airfoil blade structure, characterized in that: The system includes a supercritical airfoil blade structure and a hierarchical collaborative control system. The supercritical airfoil blade structure comprises a blade body consisting of a root, a body, and a tip. A noise-reducing plate is fixedly installed at the trailing edge of the blade body. The noise-reducing plate has a splicing groove extending inward from its leading edge. The upper wall of the splicing groove is attached to the upper surface of the blade body, and the lower wall is attached to the lower surface of the blade body. The trailing edge of the noise-reducing plate is a continuous curve or a continuous broken line. Several grooves are formed on the upper and lower surfaces of the noise-reducing plate. A melamine foam vibration-absorbing layer is sandwiched inside the trailing edge of the blade body. Vibration-absorbing grooves extend from the bottom of the splicing grooves towards the trailing edge of the noise-reducing plate, and the melamine foam vibration-absorbing layer fills these grooves. A V-shaped opening is formed at the tip of the blade body to reduce wind resistance. The hierarchical collaborative control system includes a dynamic power distribution module and an angular frequency error feedback synchronization control module. The dynamic power distribution module is used to construct a system based on grid load, wind speed, and the SOC of the energy storage system. The dynamic power allocation strategy adjusts the power distribution ratio between wind power output and energy storage system output to maintain the optimal ratio under different wind power and grid demand conditions. The angular frequency error feedback synchronization control module is used to construct the grid-connected wind turbine angular frequency error feedback synchronization control strategy. By dynamically correcting the error between wind power output and energy storage system output, the output power is synchronized with grid demand in real time.

2. The method for coordinated operation of a wind power system employing a supercritical airfoil blade structure according to claim 1, characterized in that: The dynamic power allocation module includes an energy storage system modeling unit, a wind turbine system modeling unit, and a hierarchical control structure unit; the output power control formula of the energy storage system modeling unit is: ;in, Power control commands for energy storage systems. This is a reference value for controlling the output power of the energy storage system. This represents the current actual output power of the energy storage system. The regulation coefficient of the energy storage system is given; the output power control formula of the wind turbine system modeling unit is: ;in, For wind power power control commands, This is a reference value for wind power output control. This represents the current actual output power of the wind power. The regulation coefficient for wind power is given; the hierarchical control structure unit is divided into high-level control, mid-level control, and low-level control; high-level control: calculates the global power target, determines the total power demand of the power grid, and the global power control formula is: ,in The first level is the total power control command; the second level control, based on grid load, wind speed, and the SOC state of the energy storage system, allocates the total power demand to the wind turbine system and the energy storage system using a dynamically adjusted power allocation ratio formula. The allocation ratio formula is as follows: ;in, 、 These are the power control commands for the wind power and energy storage systems at the current time t, respectively. Low-level control: Executes the power output of the wind turbine system and energy storage system to ensure that the actual output matches the control commands.

3. The method for coordinated operation of a wind power system employing a supercritical airfoil blade structure according to claim 2, characterized in that: The power allocation ratio The calculation formula is: ;in, 、 、 These are the weighted coefficients representing the impact of wind speed, grid load demand, and the SOC state of the energy storage system on the allocation coefficient. Let be the wind speed at the current time t. Let t be the current grid load demand. This represents the state of charge of the energy storage system at the current time t.

4. A method for coordinated operation of a wind power system employing a supercritical airfoil blade structure according to claim 2, characterized in that: The dynamic power allocation module also includes an energy storage recursive dynamic surface control unit, whose input is the current available power of the energy storage system. The reference phase angle input from the energy storage system to the converter and system frequency deviation The output is the reference value for the output power control of the energy storage system. The specific control logic is as follows: ;in, The rate of change of the system frequency deviation To control the gain, For the Laplace operator, Let be the time constant of the power response of the energy storage system. The time constant for the energy storage charging process. It is a high-frequency time constant. It is a low-frequency time constant.

5. The method for coordinated operation of a wind power system employing a supercritical airfoil blade structure according to claim 1, characterized in that: The angular frequency error feedback synchronization control module adjusts the virtual angular frequency of the fan through a nonlinear angular frequency feedback control function, which is: ;in, To account for the virtual angular frequency deviation of the grid-connected wind turbines, The system angular frequency, To output virtual angular frequency for grid-connected wind turbines, 、 These are the adjustment parameters for the controller. This is a parameter used to adjust the system's sensitivity to errors.

6. The method for coordinated operation of a wind power system employing a supercritical airfoil blade structure according to claim 1, characterized in that: The average ratio of the thickness of the leaf root to the chord length is 25%-35%, the average ratio of the thickness of the leaf body to the chord length is 15%-25%, and the average ratio of the thickness of the leaf tip to the chord length is 8%-15%.

7. A method for coordinated operation of a wind power system employing a supercritical airfoil blade structure according to claim 1, characterized in that: The average ratio of the thickness of the leaf root to the chord length is 30%, the average ratio of the thickness of the leaf body to the chord length is 20%, and the average ratio of the thickness of the leaf tip to the chord length is 12%.

8. A method for coordinated operation of a wind power system employing a supercritical airfoil blade structure according to claim 1, characterized in that: The blade body is coated with at least one reflective coating.

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