Permanent magnet synchronous wind generator parameter optimization system and method

Abstract

The application discloses a permanent magnet synchronous wind generator parameter optimization system and method, and particularly relates to the technical field of generator parameter optimization. The system and method reflect real wind conditions by constructing a full wind speed domain working condition matrix, establish an inertia matching boundary function to avoid coupling risks, divide a tooth slot torque interval to be compatible with positioning and stability, and finally optimize an extreme arc coefficient and a slot width in cooperation, so that the operation reliability and dynamic safety in the full working condition range are improved in cooperation.

Description

Technical Field

[0001] This invention relates to the field of generator parameter optimization technology, and more specifically, to a permanent magnet synchronous wind turbine parameter optimization system and method. Background Technology

[0002] Permanent magnet synchronous wind turbines need to operate efficiently over a wide wind speed range, achieving reliable self-starting at low wind speeds while ensuring safe braking at high wind speeds. Existing optimization methods typically focus on minimizing cogging torque to suppress vibration, but neglect its positioning function in the shutdown state: during the low wind speed startup phase, completely eliminating cogging torque can reduce the startup wind speed, but it causes the rotor to lose its necessary magnetic reluctance positioning capability in the shutdown state, making it susceptible to unexpected rotation due to light wind disturbances, thus affecting the standby reliability of the system.

[0003] The optimization of the aforementioned electromagnetic parameters is often independent of the dynamic characteristics of the electromechanical coupling system, focusing only on efficiency and pulsation suppression at the rated point. When the optimization scheme causes a slight change in the rotor's moment of inertia, it disrupts the inertial matching with the aerodynamic characteristics of the wind turbine blades. Under high-speed braking or torque impacts caused by extreme gusts, the optimized electromagnetic torque response may couple with the mechanical vibration modes of the blades, exciting torsional vibration of the main shaft. Therefore, in pursuing optimal electromagnetic performance, existing methods, by severing the mechanical positioning function of the cogging torque and the dynamic matching relationship of the electromechanical inertia, lead to a contradiction in the generator's performance across the entire wind speed range: difficulty in self-locking at low wind speeds and susceptibility to oscillation at high wind speeds. This makes it difficult for the optimization scheme to simultaneously ensure reliability and safety under all operating conditions in practical engineering implementation. Summary of the Invention

[0004] To overcome the aforementioned deficiencies of the prior art, embodiments of the present invention provide a permanent magnet synchronous wind turbine parameter optimization system and method to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: The parameter optimization method for permanent magnet synchronous wind turbines includes the following steps: The wind speed probability distribution and turbulence intensity temporal characteristics of the target wind field are obtained. By coupling instantaneous wind speed with tip speed ratio, a full wind speed domain condition matrix including low wind speed start frequency and high wind speed gust impact amplitude is constructed. Based on the full wind speed domain operating condition matrix, the starting torque requirement in the low wind speed range and the braking torque slope constraint in the high wind speed range are extracted, and an inertia matching boundary function is established. Based on the inertia matching boundary function, the cogging torque is divided into multiple target intervals, the minimum positioning reluctance torque and the maximum pulsation amplitude are extracted, and a compatibility index for smooth operation of reluctance positioning is constructed. Based on the compatibility index and the rotational speed fluctuation sequence under turbulence intensity, the starting dead zone boundary and torsional vibration sensitive frequency band are located to obtain a dual dynamic constraint domain. Based on the aforementioned dual dynamic constraint domain, the permanent magnet pole arc coefficient and the stator slot width are optimized collaboratively to generate a set of magnetic pole slot matching parameters.

[0006] In a preferred embodiment, the process of acquiring the wind speed probability distribution and turbulence intensity time series characteristics of the target wind field by coupling instantaneous wind speed with tip speed ratio to construct a full wind speed domain condition matrix including low wind speed start frequency and high wind speed gust impact amplitude is as follows: collect measured wind speed time series data of the target wind field, use the maximum likelihood method to fit the Weibull distribution parameters, and obtain the wind speed probability density function. Turbulence intensity reference values ​​are obtained from the wind turbine design specifications, and wind speed fluctuation time series that conform to turbulence characteristics are generated using an autoregressive moving average model to synthesize instantaneous wind speed sequences; combined with the wind turbine rotor radius and speed control strategy, a mapping relationship between tip speed ratio and wind speed is established. Discretize the wind speed range as The probability of wind speed occurring in each interval is statistically analyzed, and the peak and mean instantaneous wind speeds in each interval are extracted to calculate the gust factor. Based on the starting characteristics of wind turbines, determine the low wind speed starting frequency coefficient and the high wind speed gust impact amplitude; Construct a full wind speed domain operating condition matrix.

[0007] In a preferred embodiment, the process of extracting the starting torque requirement in the low wind speed range and the braking torque slope constraint in the high wind speed range based on the full wind speed range operating condition matrix, and establishing the inertia matching boundary function is as follows: extract the starting frequency coefficient of the low wind speed range in the operating condition matrix, calculate the required starting electromagnetic torque for each range in combination with the aerodynamic characteristics of the wind turbine; take the minimum value of the allowable starting time for each range, and derive the upper limit constraint of the total inertia of the starting process. Extract the gust impact amplitude in the high wind speed range of the working condition matrix and calculate the maximum rate of change of aerodynamic torque under the action of gusts. Based on the speed overshoot limit and the maximum response rate of the electromagnetic torque, the effect of the braking process on the total inertia is derived. The lower bound constraint; Establish the inertia matching boundary function under electromechanical coupling.

[0008] In a preferred embodiment, the process of dividing the cogging torque into multi-objective intervals according to the inertia matching boundary function, extracting the minimum positioning reluctance torque and the maximum pulsation amplitude, and constructing a compatibility index for smooth operation of reluctance positioning is as follows: Based on the inertia matching boundary function, determine the total inertia reference value that meets the dynamic stability requirements; and combine it with the maximum wind-induced disturbance torque in the shutdown state. Extract the minimum positioning reluctance torque required for the stop holding zone; Based on the allowable speed fluctuations and corresponding angular acceleration limits under rated operating conditions, the maximum allowable pulsation amplitude in the smooth operating range is extracted. By comparing the peak value of the cogging torque with the range of the cogging torque, a compatibility index for the smooth operation of magnetoresistive positioning is constructed.

[0009] In a preferred embodiment, the process of locating the start-up dead zone boundary and torsional vibration sensitive frequency band based on the compatibility index and the rotational speed fluctuation sequence under turbulence intensity to obtain the dual dynamic constraint domain is as follows: selecting candidate values ​​for cogging torque based on the compatibility index; The instantaneous wind speed fluctuation sequence in the low wind speed range is obtained. The transmission chain motion equation is adopted, and the rotational speed response is simulated under electromagnetic torque conditions. The rotational speed can be increased to the cut-in speed corresponding to the cut-in wind speed within the maximum allowable start-up time when the wind speed exceeds the cut-in wind speed, and the start-up success rate is obtained. The wind speed corresponding to 50% of the start-up success rate is defined as the start-up dead zone boundary, and its relationship with the cogging torque is fitted. For the instantaneous wind speed sequence in the high-wind-speed range, the same equation of motion is used to simulate the rotational speed fluctuation. A fast Fourier transform is performed on the rotational speed signal to obtain the amplitude-frequency characteristics. Continuous frequency ranges with amplitudes greater than the amplitude-frequency threshold are identified, and this is combined with the torsional natural frequency of the transmission system. Extraction and Distance less The frequency band is used as the torsional vibration sensitive frequency band; The starting dead zone boundary and the torsional vibration sensitive frequency band are used as dual dynamic constraint domains for parameter optimization.

[0010] In a preferred embodiment, the process of collaboratively optimizing the permanent magnet pole arc coefficient and the stator slot width according to the dual dynamic constraint domain to generate a set of magnetic pole slot matching parameters is as follows: setting the value range of the permanent magnet pole arc coefficient and the value range of the stator slot width. Based on electromagnetic field finite element simulation, a mapping relationship is established between the peak value of the cogging torque and the permanent magnet pole arc coefficient and the stator slot width. Establish the mapping relationship between rotor moment of inertia, permanent magnet pole arc coefficient, and stator slot width; The permanent magnet pole arc coefficient and stator slot width are discretized into 20 grid points within their respective ranges to form a parameter combination grid; the corresponding cogging torque peak and torsional natural frequency are calculated for each grid point. Select all grid points that satisfy the constraints to form a candidate parameter set. For candidate parameter sets Calculate the compatibility index for each parameter point in the dataset, and select the compatibility index. The top 5 points with the largest values ​​are selected as the optimal parameter combination; if the candidate parameter set... If the set is empty, the boundary of the torsional vibration sensitive frequency band is expanded by 10% and re-screened until a non-empty set is obtained; finally, the set of magnetic pole tooth groove matching parameters is output.

[0011] In a preferred embodiment, the permanent magnet synchronous wind turbine parameter optimization system includes an operating condition matrix construction module, an inertia matching construction module, a tooth cogging compatibility index module, a dynamic constraint module, and a parameter optimization module. The working condition matrix construction module is used to obtain the wind speed probability distribution and turbulence intensity temporal characteristics of the target wind field. By coupling instantaneous wind speed with tip speed ratio, a full wind speed domain working condition matrix is ​​constructed, which includes the low wind speed start frequency and the high wind speed gust impact amplitude. The inertia matching construction module is used to extract the starting torque requirement in the low wind speed range and the braking torque slope constraint in the high wind speed range based on the full wind speed domain operating condition matrix, and to establish the inertia matching boundary function. The tooth cogging compatibility index module is used to divide the tooth cogging torque into multiple target intervals according to the inertia matching boundary function, extract the minimum positioning reluctance torque and the maximum pulsation amplitude, and construct a compatibility index for smooth operation of reluctance positioning. The dynamic constraint module is used to locate the start-up dead zone boundary and the torsional vibration sensitive frequency band based on the compatibility index and the rotational speed fluctuation sequence under turbulence intensity, thereby obtaining a dual dynamic constraint domain. The parameter optimization module is used to collaboratively optimize the permanent magnet pole arc coefficient and the stator slot width according to the dual dynamic constraint domain, and generate a set of magnetic pole slot matching parameters.

[0012] The technical effects and advantages of this invention are as follows: 1. This application aims to solve the contradiction in existing optimization methods for permanent magnet synchronous wind turbines, which suffer from difficulty in self-locking at low wind speeds and easy oscillation at high wind speeds due to the disconnection between the cogging torque positioning function and the dynamic matching relationship of electromechanical inertia. By constructing a full-wind-speed-range operating condition matrix to reflect the real wind conditions, establishing an inertia matching boundary function to avoid coupling risks, dividing the cogging torque interval for compatible positioning and stability, and finally co-optimizing the polar arc coefficient and slot width, the application achieves a synergistic improvement in operational reliability and dynamic safety across the entire operating range.

[0013] 2. This invention constructs a full-wind-speed-domain operating condition matrix, incorporating the low-wind-speed start-up frequency and high-wind-speed gust impact characteristics in the actual wind field into the optimization model. This allows generator parameter design to no longer be limited to rated operating conditions, but to be specifically matched based on real wind data, solving the problem of insufficient adaptability to all operating conditions caused by traditional methods being detached from the actual operating environment. By establishing an inertia matching boundary function under electromechanical coupling, the rotor rotational inertia and blade aerodynamic characteristics are incorporated into a unified constraint, avoiding the risk of coupling between electromagnetic response and mechanical vibration modes under extreme gusts from the source, and significantly improving the dynamic stability during high-wind-speed braking.

[0014] 3. This invention divides the cogging torque into multiple target intervals and constructs a compatibility index, ensuring smooth operation while retaining the necessary stop positioning magnetic reluctance. This fundamentally resolves the contradiction of having both cogging torque and compatibility, enabling the generator to have reliable self-locking capability in low wind speed ranges and avoiding unexpected rotation caused by light wind disturbances. By locating the start-up dead zone boundary and the torsional vibration sensitive frequency band and forming a dual dynamic constraint domain, the dynamic behavior characteristics of the electromechanical coupling system are transformed into quantifiable optimization boundaries, enabling the parameter optimization process to actively avoid dangerous operating conditions.

[0015] 4. This invention optimizes the permanent magnet pole arc coefficient and the stator slot width in a coordinated manner. The pole arc coefficient controls the magnetic field distribution, and the slot width adjusts the cogging effect. Under the dual constraints of inertia matching and cogging compatibility, a set of magnetic pole and slot matching parameters is generated. Ultimately, it achieves a synergistic balance between low wind speed self-locking and high wind speed torsional vibration suppression, making the optimized scheme reliable and safe across the entire working condition range in actual engineering. Attached Figure Description

[0016] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to the accompanying drawings; Figure 1 This is a flowchart of the method in Embodiment 1 of the present invention; Figure 2 This is a module connection diagram of the system in Embodiment 2 of the present invention. Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] Example 1: Figure 1 The present invention provides a parameter optimization method for permanent magnet synchronous wind turbine generators, comprising the following steps: The wind speed probability distribution and turbulence intensity temporal characteristics of the target wind field are obtained. By coupling instantaneous wind speed with tip speed ratio, a full wind speed domain condition matrix including low wind speed start frequency and high wind speed gust impact amplitude is constructed. Based on the full wind speed domain operating condition matrix, the starting torque requirement in the low wind speed range and the braking torque slope constraint in the high wind speed range are extracted, and the inertia matching boundary function under electromechanical coupling is established. Based on the inertia matching boundary function, the cogging torque is divided into multi-objective intervals. The minimum positioning reluctance torque required for the stop holding zone and the maximum pulsation amplitude allowed for the smooth operation zone are extracted to construct the compatibility index of the cogging torque for smooth reluctance positioning operation. Based on the compatibility index and the rotational speed fluctuation sequence under turbulence intensity, the starting dead zone boundary of the extremely low wind speed section and the torsional vibration sensitive frequency band under extreme gusts are located, and the dual dynamic constraint domain for parameter optimization is obtained. Based on the aforementioned dual dynamic constraint domain, the permanent magnet pole arc coefficient and stator slot width are optimized collaboratively to generate a set of magnetic pole slot matching parameters that take into account both low wind speed self-locking capability and high wind speed torsional vibration suppression.

[0019] In this embodiment of the invention, the process of obtaining the wind speed probability distribution and turbulence intensity temporal characteristics of the target wind field, and constructing a full-wind-domain operating condition matrix including the low-wind-speed initiation frequency and the high-wind-speed gust impact amplitude by coupling instantaneous wind speed with blade tip speed ratio, is as follows: Collect at least one year of measured wind speed time-series data for the target wind field. The maximum likelihood method is used to fit the Weibull distribution parameters to obtain the wind speed probability density function. : ,in For shape parameters, For scale parameters; The Weibull distribution is a standard mathematical model describing the statistical characteristics of wind speed. It includes a shape parameter, which determines the shape of the wind speed probability distribution curve and reflects the stability of the wind field; and a scale parameter, which reflects the average wind speed of the wind field. It should be noted that the iterative initial value approximation method of maximum likelihood estimation is adopted, that is, it is first based on the mean of the measured wind speed data. with standard deviation The initial value is estimated using the relationship between the first and second moments of the Weibull distribution, as shown in the formula: , ,in This is the gamma function; if the mean and standard deviation of the measured data are missing, then values ​​are assigned based on experience with the wind field level: for low-wind-speed wind fields (annual average wind speed ≤ 6 m / s), k0 = 1.8. 2.2, c0=5 7; For high-wind-speed wind fields (annual average wind speed ≥ 8 m / s), take k0 = 2.2. 2.8, c0=8 10. This initial value will serve as the starting point for the Newton-Raphson iteration, which iteratively solves the likelihood equation to obtain the final k and c.

[0020] Obtain turbulence intensity reference values ​​from the wind turbine design specifications. And an autoregressive moving average model is used to generate wind speed fluctuation time series that conform to turbulence characteristics. Synthesize instantaneous wind speed sequence: ,in This represents the time-varying average wind speed; combined with the wind turbine rotor radius. In conjunction with the speed control strategy, establish a mapping relationship between tip speed ratio and wind speed: ,in To achieve the optimal tip speed ratio, The maximum permissible rotational speed; the blade tip speed ratio This describes the relative relationship between the linear velocity of wind turbine blade rotation and the natural wind speed. It is a core indicator for measuring whether the wind turbine is operating at its optimal wind energy capture point. The calculation formula is as follows: ,in The rotational angular velocity of the wind turbine rotor. Instantaneous wind speed; Wind speed range Discretized Equal intervals Calculate the probability of wind speed occurring within each interval: Simultaneously, the peak value of the instantaneous wind speed within this interval is extracted. with the mean Calculate the gust factor: ; Determine the low wind speed start-up frequency coefficient based on the wind turbine start-up characteristics. : ,in For indicator functions, The cut-in wind speed for the wind turbine. This is the activation threshold coefficient; The start-up threshold coefficient is a correction coefficient used to quantify the probability that turbulence intensity will cause the fan speed to exceed the start-up threshold. It can be calibrated through experiments or simulations: for different turbulence intensities, simulate wind speed sequences and calculate the ratio of the actual number of start-ups to the number of times the wind speed exceeds the threshold to obtain an empirical function. ; High wind speed gust impact amplitude : ,in Rated wind speed, which is the minimum wind speed at which a wind turbine reaches its rated output power; Constructing a full wind speed domain operating condition matrix This is used to describe the operational probability, low-wind-speed start-up requirements, and high-wind-speed gust impact intensity within each wind speed range.

[0021] In this embodiment of the invention, the process of extracting the starting torque requirement in the low wind speed range and the braking torque slope constraint in the high wind speed range based on the full wind speed domain operating condition matrix, and establishing the inertia matching boundary function under electromechanical coupling is as follows: Extracting the working condition matrix Low to medium wind speed range Start-up frequency coefficient The required starting electromagnetic torque for each section is calculated based on the aerodynamic characteristics of the wind turbine. : ,in This represents the peak value of the cogging torque. For static friction torque, For the cut-in speed, To determine the allowed startup time; take the allowed startup time for each interval. minimum value Derivation of the effect of the start-up process on the total inertia Upper limit constraint: ,in This represents the maximum electromagnetic torque of the generator; The total inertia Generator rotor moment of inertia Equivalent moment of inertia of the blade Combining the results, we get: ; Extracting high wind speed ranges from the operating condition matrix gust impact amplitude Calculate the maximum rate of change of aerodynamic torque under gusts of wind. : ,in For the time it takes for gusts to rise, The average rotational speed over the interval. air density, To maximize wind energy utilization; According to speed overshoot limit and maximum response rate of electromagnetic torque Derivation of the effect of braking process on total inertia Lower bound constraint: ; Establishing the inertia matching boundary function under electromechanical coupling ,in This is the lower limit constraint value for the total moment of inertia during the braking process. , This is the upper limit constraint value for the total inertia during the startup process. This is used to characterize whether the current inertia meets the dynamic stability requirements across the entire wind speed domain.

[0022] In this embodiment of the invention, based on the inertia matching boundary function, the cogging torque is divided into multi-objective intervals, and the minimum positioning reluctance torque required for the stop holding zone and the maximum allowable pulsation amplitude for the smooth operation zone are extracted. The process of constructing the compatibility index of reluctance positioning smooth operation of cogging torque is as follows: According to the inertia matching boundary function Determine the total inertia reference value that meets the dynamic stability requirements. The total inertia reference value is taken as follows: and The median; Combined with the maximum wind-induced disturbance torque in the shutdown state : ,in The peak value of the extreme gust wind speed when the machine is stopped is determined by the turbulence intensity. Determined by the 95th percentile wind speed, , This refers to the pneumatic torque in the stopped state. Considering the suppression of angular acceleration due to inertia, extract the minimum positioning reluctance torque required for the stop holding region. , For the allowable speed drift during shutdown, This refers to the time it takes for gusts to rise; According to the allowable speed fluctuation under rated operating conditions (Take 1% of rated speed) and the corresponding angular acceleration limit. : , For the speed regulation period, extract the maximum allowable pulsation amplitude within the smooth operating range. ,in From an electromagnetic performance perspective, the peak cogging torque should not exceed 2% to 5% of the rated torque. Take 2% to 5%; Peak cogging torque With cogging torque range Comparison and construction of compatibility indexes for stable operation of magnetoresistive positioning : .

[0023] In this embodiment of the invention, the process of locating the start-up dead zone boundary of the extremely low wind speed range and the torsional vibration sensitive frequency band under extreme gusts, based on the compatibility index and the rotational speed fluctuation sequence under turbulence intensity, and obtaining the parameter-optimized dual dynamic constraint domain is as follows: According to the compatibility index Select candidate values ​​for cogging torque ,Pick The maximum value corresponds to the value; Obtain low wind speed range Instantaneous wind speed fluctuation sequence The motion equation of the transmission chain is adopted: ,in The torque coefficient is the electromagnetic torque. Simulate the rotational speed response under certain conditions, and statistically analyze whether the rotational speed can remain within the maximum allowable start-up time each time the wind speed exceeds the cut-in wind speed. The internal speed rises to the cut-in speed corresponding to the cut-in wind speed. To obtain the startup success rate The success rate of the startup will be 50%. The corresponding wind speed is defined as the start-up dead zone boundary. And fit its relationship with cogging torque. ,in From turbulence intensity Calibrated as ; For high wind speed sections The instantaneous wind speed sequence uses the same equation of motion ( Simulates speed fluctuations using maximum power point tracking control (MPPT) and analyzes the speed signal. The amplitude-frequency response is obtained by performing a fast Fourier transform. Identify amplitude values ​​greater than the amplitude-frequency threshold. The continuous frequency range, combined with the torsional natural frequency of the transmission system. Extraction and Distance less The frequency band is used as the torsional vibration sensitive band. ; It should be noted that the amplitude-frequency threshold Ath is selected based on the fatigue damage tolerance of the transmission system to torsional vibration and the unit's vibration standards. Specifically, the speed fluctuation is converted into an equivalent shaft-end torsional angular displacement. According to the provisions of IEC61400-1 regarding fatigue loads on transmission systems, the maximum permissible torsional angular displacement amplitude is taken. (Empirical engineering value, corresponding to the long-term fatigue limit of the main shaft of a megawatt-class unit). Therefore, the expression for the amplitude-frequency threshold in the frequency domain is determined as follows: That is, the threshold corresponding to different frequencies increases linearly with frequency.

[0024] The dead zone boundary will be activated. With torsional vibration sensitive frequency band Dual dynamic constraint domain for parameter optimization ,in The maximum allowed start-up dead zone boundary.

[0025] In this embodiment of the invention, the process of collaboratively optimizing the permanent magnet pole arc coefficient and stator slot width based on the dual dynamic constraint domain to generate a set of magnetic pole slot matching parameters that balances low-wind-speed self-locking capability and high-wind-speed torsional vibration suppression is as follows: Setting the permanent magnet pole arc coefficient The range of values and stator slot width The range of values ; The permanent magnet pole arc coefficient refers to the ratio of the arc length occupied by the permanent magnet on the rotor surface to the pole pitch (the arc length between the center lines of two adjacent magnetic poles); the stator slot width refers to the opening size of the slot on the stator core used for embedding the winding, that is, the opening width of the slot on the air gap side. Based on electromagnetic field finite element simulation, the peak value of cogging torque is established. With permanent magnet pole arc coefficient Stator slot width mapping relationship ,in Peak cogging torque With permanent magnet pole arc coefficient The mapping function for the stator slot width can be established through finite element simulation: different Combined parametric scanning is performed to extract the design value of the cogging torque waveform; Establish the rotor moment of inertia With permanent magnet pole arc coefficient Stator slot width mapping relationship Substitute into the formula for torsional natural frequency get ,in Principal axis torsional stiffness, This is the equivalent rotational inertia of the blade. It should be noted that, Represents the moment of inertia of the rotor With permanent magnet pole arc coefficient Stator slot width The mapping relationship function between them can be established through finite element simulation: In electromagnetic field finite element software, for each given set of... The software can automatically calculate the rotor's moment of inertia based on the material's density and volume. By using multiple sets of simulation data, a fit can be obtained. Numerical lookup table for these two variables; It should be noted that the mapping relationship and The model was built using finite element method (FEM) software, specifically Ansys Maxwell 2023 R2, with the solver type set to Magnetic Transient. The model is a two-dimensional axisymmetric model, and the computational domain is the range of one pole pitch of the generator. An adaptive mesh was used, with the maximum mesh edge length not exceeding one-third of the air gap length. The air gap region was fined with a three-layer mesh, and the minimum mesh angle was not less than 30 degrees. Boundary conditions were set as follows: a parallel magnetic flux boundary condition was applied to the outer circle boundary of the stator, and a perpendicular magnetic flux boundary condition was applied to the inner circle boundary of the rotor. Material parameters were defined as follows: the permanent magnet material grade was N38UH, with a remanence density of 1.23T and a coercivity of 890kA / m; the silicon steel sheet material grade was DW310-35, with the magnetization curve using BH data provided by the manufacturer, and a conductivity of 2.0e6 S / m; the coil material was copper, with a resistivity of 0.0175 Ω·mm² / m. Mesh independence verification was performed before simulation to ensure that the torque calculation result variation was less than 1%. Will , Within the range of values, each value is discretized into 20 grid points to form a parameter combination grid. Calculate the peak cogging torque for each grid point. and torsional natural frequency ; Filtering that satisfies constraints and All grid points constitute the candidate parameter set. For candidate parameter sets Compatibility index is calculated for each parameter point in the calculation. Select compatibility index The top 5 points with the largest values ​​are selected as the optimal parameter combination; if the candidate parameter set... If the set is empty, the boundary of the torsional vibration sensitive frequency band is expanded by 10% and re-screened until a non-empty set is obtained; finally, the set of magnetic pole tooth groove matching parameters is output.

[0026] This invention constructs a full-wind-speed-domain operating condition matrix, incorporating the low-wind-speed start-up frequency and high-wind-speed gust impact characteristics of actual wind fields into the optimization model. This allows generator parameter design to move beyond the limitations of rated operating conditions and instead perform targeted matching based on real wind data, solving the problem of insufficient adaptability to all operating conditions caused by traditional methods being detached from the actual operating environment. By establishing an inertia matching boundary function under electromechanical coupling, the rotor rotational inertia and blade aerodynamic characteristics are incorporated into a unified constraint, fundamentally avoiding the risk of coupling between electromagnetic response and mechanical vibration modes under extreme gusts, significantly improving dynamic stability during high-wind-speed braking. By dividing the cogging torque into multi-objective intervals and constructing a compatibility index, necessary shutdown positioning magnetic reluctance is retained while ensuring smooth operation, fundamentally addressing the issue. The above method resolves the contradiction between the need for cogging torque and the need for high-speed torsion vibration, enabling the generator to have reliable self-locking capability in low wind speed ranges and avoiding unexpected rotation caused by light wind disturbances. By locating the start-up dead zone boundary and the torsional vibration sensitive frequency band and forming a dual dynamic constraint domain, the dynamic behavior characteristics of the electromechanical coupling system are transformed into quantifiable optimization boundaries, allowing the parameter optimization process to actively avoid dangerous operating conditions. By coordinating the optimization of the permanent magnet pole arc coefficient and the stator slot width, the magnetic field distribution is controlled by the pole arc coefficient and the cogging effect is adjusted by the slot width. Under the premise of satisfying the dual constraints of inertia matching and cogging compatibility, a magnetic pole cogging matching parameter set is generated. Ultimately, a synergistic balance between low wind speed self-locking and high wind speed torsional vibration suppression is achieved, making the optimized scheme reliable and safe across the entire operating range in actual engineering.

[0027] This application aims to address the contradiction in existing optimization methods for permanent magnet synchronous wind turbines, which suffer from difficulties in self-locking at low wind speeds and susceptibility to oscillation at high wind speeds due to the disconnect between the cogging torque positioning function and the dynamic matching relationship of electromechanical inertia. By constructing a full-wind-speed-range operating condition matrix to reflect the actual wind conditions, establishing an inertia matching boundary function to avoid coupling risks, dividing the cogging torque interval for compatible positioning and stability, and finally co-optimizing the polar arc coefficient and slot width, the application achieves a synergistic improvement in operational reliability and dynamic safety across the entire operating range.

[0028] Example 2: This example introduces a parameter optimization system for permanent magnet synchronous wind turbines, such as... Figure 2 As shown, it includes a working condition matrix construction module, an inertia matching construction module, a tooth cogging compatibility index module, a dynamic constraint module, and a parameter optimization module; The working condition matrix construction module is used to obtain the wind speed probability distribution and turbulence intensity temporal characteristics of the target wind field. By coupling instantaneous wind speed with tip speed ratio, a full wind speed domain working condition matrix is ​​constructed, which includes the low wind speed start frequency and the high wind speed gust impact amplitude. The inertia matching construction module is used to extract the starting torque requirement in the low wind speed range and the braking torque slope constraint in the high wind speed range based on the full wind speed domain operating condition matrix, and to establish the inertia matching boundary function. The tooth cogging compatibility index module is used to divide the tooth cogging torque into multiple target intervals according to the inertia matching boundary function, extract the minimum positioning reluctance torque and the maximum pulsation amplitude, and construct a compatibility index for smooth operation of reluctance positioning. The dynamic constraint module is used to locate the start-up dead zone boundary and the torsional vibration sensitive frequency band based on the compatibility index and the rotational speed fluctuation sequence under turbulence intensity, thereby obtaining a dual dynamic constraint domain. The parameter optimization module is used to collaboratively optimize the permanent magnet pole arc coefficient and the stator slot width according to the dual dynamic constraint domain, and generate a set of magnetic pole slot matching parameters.

[0029] It should be noted that the various modules are executed sequentially through signal connections and data transmission: the operating condition matrix construction module inputs the generated full wind speed domain operating condition matrix into the inertia matching construction module to extract start-up and braking constraints; the inertia matching construction module transmits the calculated inertia boundary to the tooth cogging compatibility index module as the basis for dividing the tooth cogging torque range; the tooth cogging compatibility index module outputs the compatibility index and torque limit to the dynamic constraint module to locate the start-up dead zone and torsional vibration sensitive frequency band; the dynamic constraint module inputs the dual dynamic constraint domain into the parameter optimization module as the constraint condition for the coordinated optimization of the pole arc coefficient and the slot width; the parameter optimization module finally outputs a magnetic pole-tooth cogging matching parameter set that satisfies the reliability and safety of the entire operating condition.

[0030] The above formulas are all dimensionless calculations. The formulas are derived from software simulations based on a large amount of collected data to obtain the most recent real-world results. The preset parameters in the formulas are set by those skilled in the art according to the actual situation.

[0031] The above embodiments can be implemented, in whole or in part, by software, hardware, firmware, or any other combination thereof. When implemented using software, the above embodiments can be implemented, in whole or in part, as a computer program product. The computer program product includes one or more computer instructions or computer programs. When the computer instructions or computer programs are loaded or executed on a computer, all or part of the processes or functions described in the embodiments of this application are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more sets of available media. The available medium can be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium. A semiconductor medium can be a solid-state drive.

[0032] It should be understood that in the various embodiments of this application, the order of the above-mentioned processes does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0033] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working process of the system and method described above can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0034] In the several embodiments provided in this application, it should be understood that the disclosed systems and methods can be implemented in other ways.

[0035] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for optimizing parameters of a permanent magnet synchronous wind turbine, characterized in that: The steps include the following: The wind speed probability distribution and turbulence intensity temporal characteristics of the target wind field are obtained. By coupling instantaneous wind speed with tip speed ratio, a full wind speed domain condition matrix including low wind speed start frequency and high wind speed gust impact amplitude is constructed. Based on the full wind speed domain operating condition matrix, the starting torque requirement in the low wind speed range and the braking torque slope constraint in the high wind speed range are extracted, and an inertia matching boundary function is established. Based on the inertia matching boundary function, the cogging torque is divided into multiple target intervals, the minimum positioning reluctance torque and the maximum pulsation amplitude are extracted, and a compatibility index for smooth operation of reluctance positioning is constructed. Based on the compatibility index and the rotational speed fluctuation sequence under turbulence intensity, the starting dead zone boundary and torsional vibration sensitive frequency band are located to obtain a dual dynamic constraint domain. Based on the dual dynamic constraint domain, the permanent magnet pole arc coefficient and the stator slot width are optimized collaboratively to generate a set of magnetic pole slot matching parameters. The process of dividing the cogging torque into multi-objective intervals according to the inertia matching boundary function, extracting the minimum positioning reluctance torque and the maximum pulsation amplitude, and constructing the compatibility index of reluctance positioning stable operation is as follows: Based on the inertia matching boundary function, determine the total inertia reference value that meets the dynamic stability requirements; and combine it with the maximum wind-induced disturbance torque in the shutdown state. Extract the minimum positioning reluctance torque required for the stop holding zone; Based on the allowable speed fluctuations and corresponding angular acceleration limits under rated operating conditions, the maximum allowable pulsation amplitude in the smooth operating range is extracted. By comparing the peak value of the cogging torque with the range of the cogging torque, a compatibility index for the smooth operation of magnetoresistive positioning is constructed. The process of locating the start-up dead zone boundary and torsional vibration sensitive frequency band based on the compatibility index and the rotational speed fluctuation sequence under turbulence intensity, and obtaining the dual dynamic constraint domain, is as follows: Selecting candidate values ​​for cogging torque based on the compatibility index; The instantaneous wind speed fluctuation sequence of the low wind speed range is obtained. The transmission chain motion equation is adopted, and the rotational speed response is simulated under electromagnetic torque conditions. The rotational speed can be increased to the cut-in speed corresponding to the cut-in wind speed within the maximum allowable start-up time when the wind speed exceeds the cut-in wind speed to obtain the start-up success rate. The wind speed corresponding to 50% of the start-up success rate is defined as the start-up dead zone boundary, and its relationship with the cogging torque is fitted. For the instantaneous wind speed sequence in the high-wind-speed range, the same equation of motion is used to simulate the rotational speed fluctuation. A fast Fourier transform is performed on the rotational speed signal to obtain the amplitude-frequency characteristics. Continuous frequency ranges with amplitudes greater than the amplitude-frequency threshold are identified, and this is combined with the torsional natural frequency of the transmission system. Extraction and Distance less The frequency band is used as the torsional vibration sensitive frequency band; The starting dead zone boundary and the torsional vibration sensitive frequency band are used as dual dynamic constraint domains for parameter optimization.

2. The parameter optimization method for permanent magnet synchronous wind turbine generator according to claim 1, characterized in that: The process of acquiring the wind speed probability distribution and turbulence intensity time series characteristics of the target wind field, and constructing a full wind speed domain condition matrix including the low wind speed start frequency and the high wind speed gust impact amplitude by coupling instantaneous wind speed with blade tip speed ratio, is as follows: collect measured wind speed time series data of the target wind field, use the maximum likelihood method to fit the Weibull distribution parameters, and obtain the wind speed probability density function. Turbulence intensity reference values ​​are obtained from the wind turbine design specifications, and wind speed fluctuation time series that conform to turbulence characteristics are generated using an autoregressive moving average model to synthesize instantaneous wind speed sequences; combined with the wind turbine rotor radius and speed control strategy, a mapping relationship between tip speed ratio and wind speed is established. Discretize the wind speed range as The probability of wind speed occurring in each interval is statistically analyzed, and the peak and mean instantaneous wind speeds in each interval are extracted to calculate the gust factor. Based on the starting characteristics of wind turbines, determine the low wind speed starting frequency coefficient and the high wind speed gust impact amplitude; Construct a full wind speed domain operating condition matrix.

3. The parameter optimization method for permanent magnet synchronous wind turbine generator according to claim 2, characterized in that: The process of extracting the starting torque requirement in the low wind speed range and the braking torque slope constraint in the high wind speed range based on the full wind speed range operating condition matrix, and establishing the inertia matching boundary function is as follows: extract the starting frequency coefficient of the low wind speed range in the operating condition matrix, calculate the required starting electromagnetic torque for each range in combination with the aerodynamic characteristics of the wind turbine; take the minimum value of the allowable starting time for each range, and derive the upper limit constraint of the total inertia of the starting process. Extract the gust impact amplitude in the high wind speed range of the working condition matrix and calculate the maximum rate of change of aerodynamic torque under the action of gusts. Based on the speed overshoot limit and the maximum response rate of electromagnetic torque, the lower limit constraint of the total inertia during the braking process is derived. Establish the inertia matching boundary function under electromechanical coupling.

4. The parameter optimization method for permanent magnet synchronous wind turbine generator according to claim 1, characterized in that: The process of generating a set of magnetic pole tooth matching parameters by collaboratively optimizing the permanent magnet pole arc coefficient and the stator slot width according to the dual dynamic constraint domain is as follows: setting the value range of the permanent magnet pole arc coefficient and the value range of the stator slot width. Based on electromagnetic field finite element simulation, a mapping relationship is established between the peak value of the cogging torque and the permanent magnet pole arc coefficient and the stator slot width. Establish the mapping relationship between rotor moment of inertia, permanent magnet pole arc coefficient, and stator slot width; The permanent magnet pole arc coefficient and stator slot width are discretized into 20 grid points within their respective ranges to form a parameter combination grid; the corresponding cogging torque peak and torsional natural frequency are calculated for each grid point. Select all grid points that satisfy the constraints to form a candidate parameter set. For candidate parameter sets Calculate the compatibility index for each parameter point in the dataset, and select the compatibility index. The top 5 points with the largest values ​​are selected as the optimal parameter combination; if the candidate parameter set... If the set is empty, the boundary of the torsional vibration sensitive frequency band is expanded by 10% and re-screened until a non-empty set is obtained; finally, the set of magnetic pole tooth groove matching parameters is output.

5. A parameter optimization system for a permanent magnet synchronous wind turbine, used to implement the parameter optimization method for a permanent magnet synchronous wind turbine as described in any one of claims 1-4, characterized in that: It includes a working condition matrix construction module, an inertia matching construction module, a tooth cogging compatibility index module, a dynamic constraint module, and a parameter optimization module; The working condition matrix construction module is used to obtain the wind speed probability distribution and turbulence intensity temporal characteristics of the target wind field. By coupling instantaneous wind speed with tip speed ratio, a full wind speed domain working condition matrix is ​​constructed, which includes the low wind speed start frequency and the high wind speed gust impact amplitude. The inertia matching construction module is used to extract the starting torque requirement in the low wind speed range and the braking torque slope constraint in the high wind speed range based on the full wind speed domain operating condition matrix, and to establish the inertia matching boundary function. The tooth cogging compatibility index module is used to divide the tooth cogging torque into multiple target intervals according to the inertia matching boundary function, extract the minimum positioning reluctance torque and the maximum pulsation amplitude, and construct a compatibility index for smooth operation of reluctance positioning. The dynamic constraint module is used to locate the start-up dead zone boundary and the torsional vibration sensitive frequency band based on the compatibility index and the rotational speed fluctuation sequence under turbulence intensity, thereby obtaining a dual dynamic constraint domain. The parameter optimization module is used to collaboratively optimize the permanent magnet pole arc coefficient and the stator slot width according to the dual dynamic constraint domain, and generate a set of magnetic pole slot matching parameters.

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