Rotational speed control method and device, vertical axis wind turbine and storage medium

Abstract

Embodiments of the present application provide a rotating speed control method and device, a vertical axis wind turbine and a storage medium, and relate to the technical field of wind turbine control. The method adjusts the motor side load voltage which is inversely related to the rotating speed of the vertical axis wind turbine, according to the operating stage of the vertical axis wind turbine, the real-time tip speed ratio, the real-time rotating speed, and the preset parameters obtained from the corresponding tip speed ratio-power coefficient curve of the vertical axis wind turbine, to control the rotating speed of the vertical axis wind turbine in each operating stage, so as to take the tip speed ratio and the real-time rotating speed as the control variables, integrate all operating stages such as real-time calibration, dead zone identification, resonance avoidance, power tracking and safe shutdown into the same control framework, and enable the vertical axis wind turbine to have the intelligent operating ability of "acting according to the wind and adjusting the rotating speed according to the demand" like a wind turbine with variable pitch.

Description

Technical Field

[0001] This invention relates to the field of wind turbine control technology, and more specifically, to a speed control method, device, vertical axis wind turbine, and storage medium. Background Technology

[0002] Vertical axis wind turbines have received widespread attention in recent years in the fields of small and medium-sized off-grid power supply and microgrids due to their advantages such as insensitivity to wind direction, high potential for low starting wind speed, compact structure, and suitability for urban / distributed scenarios.

[0003] However, the startup process of vertical axis wind turbines is affected by factors such as static friction torque, unstable airflow adhesion at low wind speeds, and large torque pulsation, exhibiting significant startup uncertainty.

[0004] Furthermore, vertical axis wind turbines all use variable speed control and have no pitch system, so they cannot avoid coinciding with the resonant speed during the process from standstill to operation.

[0005] Furthermore, when vertical axis wind turbines cut off at high wind speeds, relying solely on air resistance or mechanical braking results in sluggish response and severe wear. Existing speed control strategies often directly apply short-circuit or constant high-resistance loads, which can easily lead to overvoltage or electromagnetic torque surges due to sudden speed drops, causing converter damage or excessive transient stress on the structure. Summary of the Invention

[0006] In view of this, the purpose of the present invention is to provide a speed control method, device, vertical axis wind turbine generator and storage medium.

[0007] To achieve the above objectives, the technical solutions adopted in the embodiments of the present invention are as follows: In a first aspect, the present invention provides a speed control method applied to a control device for a vertical axis wind turbine generator, the method comprising: Obtain the real-time rotational speed and tip speed ratio of the vertical axis wind turbine; Based on the operating stage of the vertical axis wind turbine, the real-time rotational speed, the tip speed ratio, and preset parameters calibrated from the tip speed ratio-power coefficient relationship curve corresponding to the vertical axis wind turbine, the motor-side load voltage of the vertical axis wind turbine is adjusted to control the rotational speed of the vertical axis wind turbine, wherein the rotational speed of the vertical axis wind turbine is inversely correlated with the motor-side load voltage.

[0008] Optionally, the preset parameters include a preset dead zone tip speed ratio range and a preset cut-out speed. The step of adjusting the motor-side load voltage of the vertical axis wind turbine based on the operating stage of the vertical axis wind turbine, the real-time speed, the tip speed ratio, and the preset parameters calibrated from the tip speed ratio-power coefficient relationship curve corresponding to the vertical axis wind turbine includes: When the operation phase is the self-starting phase, the load voltage on the motor side is adjusted according to the blade tip speed ratio and the preset dead zone blade tip speed ratio range so that the vertical axis wind turbine can start successfully. When the operation phase is the power generation phase, the wind speed change trend is obtained, and the load voltage on the motor side is adjusted according to the real-time rotational speed and the wind speed change trend to avoid resonance of the vertical axis wind turbine. When the operation phase is a shutdown phase, the load voltage on the motor side is adjusted according to the real-time rotational speed and the preset cut-out rotational speed to ensure safe braking of the vertical axis wind turbine.

[0009] Optionally, the step of adjusting the motor-side load voltage according to the tip speed ratio and the preset dead zone tip speed ratio range includes: If the tip speed ratio is greater than the upper limit of the preset dead zone tip speed ratio range, the load voltage on the motor side is reduced according to the first strategy to increase the rotational speed of the vertical axis wind turbine.

[0010] Optionally, the preset parameters further include a preset resonant speed, and the step of adjusting the motor-side load voltage according to the real-time speed and the wind speed change trend includes: If the wind speed change trend is a continuous increasing trend and the difference between the real-time rotational speed and the preset resonance rotational speed is less than the preset value, then the load voltage on the motor side is reduced according to the second strategy so that the rotational speed of the vertical axis wind turbine exceeds the resonance rotational speed range of the vertical axis wind turbine.

[0011] Optionally, the step of adjusting the motor-side load voltage according to the tip speed ratio and the wind speed variation trend further includes: If the wind speed change trend is a continuous decreasing trend and the difference between the real-time rotational speed and the preset resonance rotational speed is less than the preset value, then the load voltage on the motor side is increased according to the third strategy so that the rotational speed of the vertical axis wind turbine exceeds the resonance rotational speed range of the vertical axis wind turbine.

[0012] Optionally, the preset parameters further include a preset effective tip speed ratio. The step of adjusting the motor-side load voltage of the vertical axis wind turbine based on the operating stage of the vertical axis wind turbine, the real-time rotational speed, the tip speed ratio, and the preset parameters calibrated from the tip speed ratio-power coefficient relationship curve corresponding to the vertical axis wind turbine further includes: When the operation phase is the power generation phase and the wind speed change trend is a stable fluctuation trend, the load voltage on the motor side is adjusted according to the difference between the tip speed ratio and the preset effective tip speed ratio, so that the tip speed ratio is within the fluctuation range corresponding to the preset effective tip speed ratio.

[0013] Optionally, the step of adjusting the motor-side load voltage based on the real-time rotational speed and the preset cut-out rotational speed includes: If the real-time rotational speed is greater than the preset cut-out rotational speed, the load voltage on the motor side is increased according to the fourth strategy to reduce the rotational speed of the vertical axis wind turbine to a preset safety threshold.

[0014] In a second aspect, the present invention provides a speed control device applied to a control device for a vertical axis wind turbine generator, the device comprising: The acquisition module is used to acquire the real-time rotational speed and tip speed ratio of the vertical axis wind turbine. The control module is used to adjust the motor-side load voltage of the vertical axis wind turbine according to the operating stage of the vertical axis wind turbine, the real-time speed, the tip speed ratio, and preset parameters calibrated from the tip speed ratio-power coefficient relationship curve corresponding to the vertical axis wind turbine, so as to control the speed of the vertical axis wind turbine. The speed of the vertical axis wind turbine is inversely correlated with the motor-side load voltage.

[0015] Thirdly, the present invention provides a vertical axis wind turbine generator, including a control device, the control device including a processor and a memory, the memory storing machine-executable instructions that can be executed by the processor, the processor executing the machine-executable instructions to implement the speed control method described in the first aspect above.

[0016] Fourthly, the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the speed control method as described in the first aspect above.

[0017] The speed control method, device, vertical axis wind turbine, and storage medium provided in this embodiment of the invention obtain the real-time speed and tip speed ratio of the vertical axis wind turbine; based on the operating stage of the vertical axis wind turbine, the real-time speed, the tip speed ratio, and preset parameters calibrated from the tip speed ratio-power coefficient relationship curve corresponding to the vertical axis wind turbine, the motor-side load voltage of the vertical axis wind turbine is adjusted to control the speed of the vertical axis wind turbine, wherein the speed of the vertical axis wind turbine is inversely correlated with the motor-side load voltage. Because the embodiments of the present invention adjust the motor-side load voltage, which is inversely correlated with the speed of the vertical axis wind turbine, based on the operating stage of the vertical axis wind turbine, the real-time acquired tip speed ratio and speed, and the preset parameters calibrated from the tip speed ratio-power coefficient relationship curve corresponding to the vertical axis wind turbine, the speed of the vertical axis wind turbine is controlled in each operating stage. Thus, by using the tip speed ratio and real-time speed as control variables, all operating stages such as real-time calibration, dead zone identification, resonance avoidance, power point tracking, and safe shutdown are incorporated into the same control framework, enabling the vertical axis wind turbine to have the intelligent operation capability of "acting according to the wind and adjusting speed as needed," just like a pitch-equipped unit.

[0018] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This figure shows a schematic block diagram of a control device provided in an embodiment of the present invention; Figure 2 The figure shows the relationship between the maximum power coefficient and the tip speed ratio of a vertical axis wind turbine with different solidity according to an embodiment of the present invention. Figure 3 The diagram shows the dynamic evolution curve of the angle of attack of a vertical axis wind turbine as a function of the tip speed ratio, according to an embodiment of the present invention. Figure 4 This diagram illustrates the velocity analysis of the thrust experienced by a vertical axis wind turbine according to an embodiment of the present invention. Figure 5 The diagram shows the tip speed ratio variation curve of a vertical axis wind turbine during its self-starting process, according to an embodiment of the present invention. Figure 6This invention provides a graph showing the relationship between the angle of attack and thrust coefficient of a vertical axis wind turbine. Figure 7 A schematic flowchart of a speed control method provided by an embodiment of the present invention is shown; Figure 8 This invention provides a graph showing the relationship between rotational speed and motor-side load voltage during a smooth passage through a "dead zone" according to an embodiment of the invention. Figure 9 This invention provides a graph showing the relationship between rotational speed and motor-side load voltage during resonance avoidance, according to an embodiment of the invention. Figure 10 A functional block diagram of a speed control device provided in an embodiment of the present invention is shown.

[0021] Icons: 100-Control device; 110-Memory; 120-Processor; 130-Communication module; 200-Speed ​​control device; 201-Acquisition module; 202-Control module. Detailed Implementation

[0022] 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. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0023] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0024] It should be noted that relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0025] The embodiments of the present invention first provide a detailed introduction to the technical bottlenecks currently faced by vertical axis wind turbine generators in terms of speed control.

[0026] For vertical axis wind turbine generators (such as the Darrieus / H type), the mainstream control methods have the following three fundamental limitations: First, the uncontrollable "dead zone" of self-starting leads to a serious lack of startup reliability.

[0027] In the conventional control strategy, during the acceleration process of a vertical axis wind turbine from rest, when the tip speed ratio (TSR), hereinafter denoted as λ, enters the range of approximately 0.8–1.3 (the range depends on the solidity σ of the vertical axis wind turbine), the aerodynamic thrust coefficient C... t The near-zero or negative values ​​result in a net drive torque that remains consistently below the sum of mechanical friction and electromagnetic load, creating a typical "pseudo-stable plateau." This phenomenon is particularly pronounced in medium-solidity (σ≈0.25–0.35) vertical axis wind turbines. Field measurements show that vertical axis wind turbines often remain stagnant for over 100 seconds near λ≈1.2 (corresponding to a speed of approximately 229 rpm), unable to spontaneously transition to the high-efficiency power generation zone (λ≈3–5). Current technologies lack effective pitch intervention methods, relying solely on natural wind speed fluctuations to overcome this "dead zone," resulting in a high start-up failure rate and sluggish response.

[0028] Second, resonance avoidance relies on empirical thresholds and lacks dynamic collaborative control capabilities.

[0029] While variable-speed operation can broaden the power capture bandwidth, it inevitably causes the vertical axis wind turbine's speed to sweep across the natural frequency ranges of the tower's first-order bending mode (approximately 120–180 rpm) and the drive train's torsional vibration mode (approximately 250–320 rpm). Existing solutions often employ static speed limiting or open-loop filtering frequency hopping, which essentially sacrifices power generation continuity for structural safety: forced speed reduction leads to power loss; sudden speed jumps cause current surges and a sharp increase in mechanical stress. More importantly, these methods do not couple resonance avoidance with maximum power point tracking (MPPT) modeling. When the vertical axis wind turbine is running, it cannot autonomously avoid the resonant speed range, necessitating the design of a control method to smoothly navigate through this range.

[0030] Third, the accuracy of MPPT control is constrained by both model drift and measurement noise.

[0031] Due to the strong aerodynamic characteristics of vertical axis wind turbines, existing MPPT strategies (such as those based on power gradient or lookup tables) generally rely on a pre-defined C. p –λ theoretical model. However, in actual operation, factors such as changes in air density, blade surface fouling, and fluctuations in turbulence intensity can all lead to changes in C. pThe –λ relationship undergoes a systematic shift (i.e., “model drift”). For small and medium-sized vertical axis wind turbines (swept area < 200m²), their inertia is small and their response is fast, making them more prone to speed oscillations and power fluctuations due to model mismatch, which further exacerbates the risk of “dead zone” recurrence and resonance probability.

[0032] To overcome the shortcomings of the prior art, embodiments of the present invention provide a speed control method, device, vertical axis wind turbine generator, and storage medium, which will be described in detail below.

[0033] Please refer to Figure 1 This is a block diagram of a control device 100 for a vertical axis wind turbine. The control device 100 includes a memory 110, a processor 120, and a communication module 130. The memory 110, processor 120, and communication module 130 are electrically connected directly or indirectly to each other to achieve data transmission or interaction. For example, these components can be electrically connected to each other through one or more communication buses or signal lines.

[0034] The memory 110 is used to store programs or data. The memory 110 may be, but is not limited to, random access memory (RAM), read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), etc.

[0035] The processor 120 is used to read / write data or programs stored in the memory 110 and to perform corresponding functions.

[0036] The communication module 130 is used to establish a communication connection between the control device 100 and other communication terminals through the network, and to send and receive data through the network.

[0037] It should be understood that, Figure 1 The structure shown is only a schematic diagram of the control device 100. The control device 100 may also include a... Figure 1 The more or fewer components shown, or having the same Figure 1 The different configurations shown. Figure 1 The components shown can be implemented using hardware, software, or a combination thereof.

[0038] To enable those skilled in the art to accurately understand the technical premise and physical basis of the speed control method provided in the embodiments of the present invention, the key aerodynamic characteristics of the vertical axis wind turbine involved are explained below.

[0039] (1) Definitions and physical significance of tip speed ratio λ and solidity σ.

[0040] The tip speed ratio λ is defined as the ratio of the tip linear velocity of a blade in a vertical axis wind turbine to the incoming wind speed.

[0041] Reality σ is defined as the total projected area of ​​all blades of a vertical axis wind turbine. Area of ​​the swept cylinder The ratio. The highest power coefficient C of vertical axis wind turbines with different σ. p The relationship with the tip speed ratio λ is as follows: Figure 2 As shown, it can be seen that a high σ vertical axis wind turbine enhances low wind speed torque output but reduces C. p Low-σ vertical axis wind turbines improve maximum power coefficient C p However, this exacerbates the difficulty of starting up.

[0042] (2) The aerodynamic mechanism of the “dead zone” phenomenon.

[0043] The self-starting process of a vertical axis wind turbine is essentially the result of the dynamic evolution of the angle of attack α with λ, such as... Figure 3 As shown, the lower λ is, the greater the swing of α in the range of θ∈[0°, 180°] (θ is the azimuth angle), and it falls significantly into the airfoil stall region.

[0044] It should be specifically pointed out that "thrust" is the component of the airflow acting on the blades, perpendicular to the direction of the outrigger (see...). Figure 4 This force generates driving torque around the center of the vertical axis wind turbine, which is the only aerodynamic source that enables self-starting and continuous acceleration.

[0045] Based on measured and simulation results (taking the Darrieus type unit with a reality σ≈0.3 as an example), its self-starting process can be divided into three stages (see...). Figure 5 ): Phase 1 (Linear Acceleration): λ accelerates from 0 to approximately 1.2, reaching a speed of 183 rpm, taking about 50 seconds. During this phase, the angle of attack swing is large, but the average thrust coefficient C... t >0 (small absolute value) generates positive net torque, supporting initial acceleration; The second stage (plateau / false stability / "dead zone"): Stagnation occurs around λ≈1.2, with the engine speed slowly climbing to 229 rpm, lasting for nearly 100 seconds. During this stage, C... t The torque oscillates repeatedly near zero, and the net torque approaches zero, making it unable to effectively overcome mechanical friction and electromagnetic load, thus creating a starting "dead zone". The third stage (breakthrough period): Once λ exceeds the critical threshold (≈1.5), the angle of attack distribution rapidly contracts and enters the high-efficiency lift zone, C t Significantly increased (see) Figure 6 Within 10 seconds, λ jumps from 1.5 to 3.0, and the speed increases sharply from 229 rpm to 458 rpm, eventually stabilizing at a high-efficiency power generation condition of λ≈3.0 (speed≈458 rpm).

[0046] Figure 6 This further demonstrates that under low λ conditions, the angle of attack |α| of the blades of the vertical axis wind turbine exceeds ±90° at most azimuth positions.

[0047] The following is a detailed description of the speed control method for the control device 100 applied to a vertical axis wind turbine provided in the embodiments of the present invention.

[0048] Please refer to Figure 7 The speed control method provided in this embodiment of the invention includes steps S101 to S102.

[0049] S101 obtains the real-time rotational speed and tip speed ratio of the vertical axis wind turbine.

[0050] S102, based on the operating stage of the vertical axis wind turbine, its real-time speed, tip speed ratio, and preset parameters calibrated from the tip speed ratio-power coefficient relationship curve corresponding to the vertical axis wind turbine, adjusts the load voltage on the motor side of the vertical axis wind turbine to control its speed. The speed of the vertical axis wind turbine is inversely correlated with the load voltage on the motor side.

[0051] The tip speed ratio refers to the ratio of the linear velocity at the tip of a vertical axis wind turbine to the incoming wind speed. Its magnitude directly determines the efficiency of the vertical axis wind turbine in capturing energy from the wind. In this embodiment of the invention, the tip speed ratio of the vertical axis wind turbine is not a fixed value, but a dynamic parameter that changes in real time with wind speed and load. In practical applications, the control equipment first needs to acquire this parameter, which is calculated based on three fundamental physical quantities: the radius of the vertical axis wind turbine, the real-time rotational speed, and the measured wind speed. Subsequently, the control equipment, according to the current operating stage (start-up, power generation, or shutdown), combines the real-time rotational speed and the tip speed ratio value with a set of preset parameters pre-calibrated from the tip speed ratio-power coefficient relationship curve corresponding to the vertical axis wind turbine, to adjust the load voltage on the motor side.

[0052] The motor-side load voltage refers to the controllable DC or AC voltage applied to the generator output terminal. Its changes directly alter the magnitude of the electromagnetic torque generated by the motor: when the voltage increases, the braking effect of the motor on the vertical axis wind turbine strengthens, causing the speed of the vertical axis wind turbine to decrease; when the voltage decreases, the braking effect weakens, and the vertical axis wind turbine can accelerate under the propulsion of the airflow. Therefore, the speed of the vertical axis wind turbine is inversely correlated with the motor-side load voltage, which is the physical basis for the speed control method provided in this embodiment of the invention.

[0053] The tip speed ratio-power coefficient relationship curve is a curve formed by connecting a set of data points obtained through wind tunnel tests, numerical simulations, or long-term field operation tests, reflecting the variation of energy conversion efficiency (i.e., power coefficient) of a specific vertical axis wind turbine under different tip speed ratios; this curve is unique and is determined by the geometric structure of the vertical axis wind turbine itself.

[0054] In practical applications, the aforementioned preset parameters include key thresholds for different vertical axis wind turbine structural characteristics: where σ represents the solidity of the vertical axis wind turbine, defined as the ratio of the total blade area to the swept area of ​​the vertical axis wind turbine. The solidity reflects the "density" of the vertical axis wind turbine. This invention classifies vertical axis wind turbines into three categories based on solidity: low-solidity vertical axis wind turbines (σ=0.1–0.2), medium-solidity vertical axis wind turbines (σ=0.25–0.35), and high-solidity vertical axis wind turbines (σ=0.8–1.0), and assigns different "dead zone" tip speed ratios (denoted as σ) to each category. The range is defined as follows: 1.8–2.0 for low-solidity vertical axis wind turbines, 1.1–1.3 for medium-solidity vertical axis wind turbines, and 0.8–1.0 for high-solidity vertical axis wind turbines. This "dead zone" refers to the period within which a vertical axis wind turbine generates minimal net aerodynamic torque, insufficient to overcome its own friction and load resistance, thus leading to start-up stall or inefficient operation. Furthermore, the preset parameters also include the optimal tip speed ratio (denoted as φ) determined by the tip speed ratio–power coefficient relationship curve. The relationship between the dead zone tip speed ratio and the optimal tip speed ratio is as follows: The value of A is 0.4. The value of A is not significantly affected by the solidity of the vertical axis wind turbine, but is greatly affected by the operating environment of the vertical axis wind turbine. Its ideal fluctuation range is 0.9–1.1. Preset parameters also include the cut-out speed, used to trigger a safe shutdown; and the resonance speed and its corresponding range, used to avoid the risk of mechanical resonance between the tower and the transmission system. These parameters are all obtained through wind tunnel testing or field measurements and are fixed in the control equipment, remaining unchanged during operation.

[0055] As can be seen, by using the tip speed ratio and real-time rotational speed as control variables, the embodiments of the present invention incorporate realism calibration, dead zone identification, resonance avoidance, power tracking and safe shutdown into the same control framework, enabling the vertical axis wind turbine to have the intelligent operation capability of "acting according to the wind and adjusting speed as needed" like a pitch turbine.

[0056] In a possible implementation, embodiments of the present invention divide the entire operation process of a vertical axis wind turbine into three logically defined periods: a self-starting stage, a power generation stage, and a shutdown stage. Within each period, based on the numerical relationship between the real-time acquired tip speed ratio, real-time rotational speed, and a set of pre-calibrated threshold parameters closely related to the structural characteristics of the vertical axis wind turbine, the load voltage on the motor side is dynamically adjusted, thereby achieving phased, differentiated, and purposeful control of the rotational speed of the vertical axis wind turbine.

[0057] Furthermore, the implementation process of step S102 includes the following sub-steps S102-1 to S102-3.

[0058] S102-1, in the case of the self-starting stage of operation, adjusts the load voltage on the motor side according to the tip speed ratio and the preset dead zone tip speed ratio range to enable the vertical axis wind turbine to start successfully.

[0059] Furthermore, in this embodiment of the invention, if the tip speed ratio is greater than the upper limit of the preset dead zone tip speed ratio range, the load voltage on the motor side is reduced according to the first strategy to increase the rotational speed of the vertical axis wind turbine.

[0060] Understandably, during the self-starting phase of operation, the control equipment continuously monitors the tip speed ratio. When it increases to near or reaches the upper limit of the preset dead zone tip speed ratio range, it immediately reduces the load voltage on the motor side according to the first strategy, thereby weakening the braking effect of the motor on the vertical axis wind turbine. The vertical axis wind turbine can then accelerate and break through this range under the drive of the remaining aerodynamic thrust.

[0061] S102-2, when the operation phase is the power generation phase, acquires the wind speed change trend, and adjusts the load voltage on the motor side according to the real-time speed and wind speed change trend to avoid resonance of the vertical axis wind turbine.

[0062] Furthermore, in this embodiment of the invention, if the wind speed change trend is a continuous increasing trend and the difference between the real-time rotational speed and the preset resonant rotational speed is less than a preset value, then the load voltage on the motor side is reduced according to the second strategy so that the rotational speed of the vertical axis wind turbine exceeds the resonant rotational speed range of the vertical axis wind turbine; if the wind speed change trend is a continuous decreasing trend and the difference between the real-time rotational speed and the preset resonant rotational speed is less than a preset value, then the load voltage on the motor side is increased according to the third strategy so that the rotational speed of the vertical axis wind turbine exceeds the resonant rotational speed range of the vertical axis wind turbine.

[0063] Understandably, during the power generation phase of operation, the control equipment synchronously acquires the wind speed change trend and selects different voltage regulation strategies accordingly: if the wind speed shows a continuous increasing trend and the difference between the current real-time speed and the preset resonance speed is less than the preset value, then the second strategy is used to reduce the load voltage on the motor side, causing the vertical axis wind turbine to accelerate and jump across the resonance speed range; if the wind speed shows a continuous decreasing trend and the difference between the current real-time speed and the preset resonance speed is less than the preset value, then the third strategy is used to increase the load voltage on the motor side, causing the vertical axis wind turbine to decelerate and smoothly bypass the resonance range.

[0064] S102-3, when the operation phase is the shutdown phase, adjusts the load voltage on the motor side according to the real-time speed and the preset cut-out speed to ensure safe braking of the vertical axis wind turbine.

[0065] Furthermore, in this embodiment of the invention, if the real-time rotational speed is greater than the preset cut-out rotational speed, the load voltage on the motor side is increased according to the fourth strategy to reduce the rotational speed of the vertical axis wind turbine to a preset safety threshold.

[0066] Understandably, when the operation phase is a shutdown phase, if the real-time speed is greater than the preset cut-out speed, the control equipment immediately increases the load voltage on the motor side according to the fourth strategy, significantly enhancing the electromagnetic braking torque, so that the speed of the vertical axis wind turbine generator drops rapidly; after the speed drops to the preset safety threshold, the mechanical brake is triggered to complete the final lock, thereby avoiding the risk of overspeed runaway due to inertia.

[0067] Furthermore, step S102 also includes sub-step S102-4: when the operation phase is the power generation phase and the wind speed change trend is a stable fluctuation trend, the load voltage on the motor side is adjusted according to the difference between the tip speed ratio and the preset effective tip speed ratio, so that the tip speed ratio is within the fluctuation range corresponding to the preset effective tip speed ratio.

[0068] The preset effective tip speed ratio is derived from the peak point of the tip speed ratio-power coefficient relationship curve. When the wind speed change trend is a stable fluctuation trend, the control equipment adjusts the load voltage on the motor side proportionally according to the difference between the tip speed ratio and the preset effective tip speed ratio, so that the tip speed ratio is stably maintained within the fluctuation range, thereby ensuring that the power coefficient is always in the high range and improving the overall power generation efficiency.

[0069] For example, such as Figure 8 As shown, the vertical axis wind turbine starts up, and the speed increases slowly. Less than The motor is not connected to a load and is in an idling state (corresponding to...) Figure 8 Stage ① in the middle.

[0070] When the vertical axis wind turbine reaches the cut-in speed (point A), the motor begins to connect to the load, the control voltage rises slowly according to a parabola, and the vertical axis wind turbine speed increases slowly until point B, at which point the vertical axis wind turbine... near The voltage on both sides of the motor drops rapidly, causing the vertical axis wind turbine to quickly exceed the "dead zone" of the blade tip speed ratio. (correspond Figure 8 (Stage ②)

[0071] Through the "dead zone" tip speed ratio Afterwards, the rotational speed reaches point C, at which point the tip speed ratio is approximately... At this point, it is assumed that the vertical axis wind turbine has passed the "dead zone" (corresponding to...). Figure 8 (Stage ③ in the process).

[0072] Upon detecting a continuous increase in wind speed, the control equipment increases the load on both sides of the motor in a parabolic manner. At this point, the tip speed ratio of the vertical axis wind turbine is... Continue to increase, as As the speed increases to point D (initially rapid then slowing, with a gradually decreasing slope), the power coefficient of the vertical axis wind turbine also gradually increases. Point D represents the optimal tip speed ratio. The point (corresponding to) Figure 8 (Stage 4)

[0073] Once in a stable operating range, if the wind speed is relatively stable with minimal fluctuations, the vertical axis wind turbine's rotational speed will remain within a certain range for stable power generation, with a blade tip speed ratio range of 0.9. -1.1 If the wind speed continues to increase steadily, as the tip speed ratio deviates from the optimal tip speed ratio... The power factor of a vertical axis wind turbine decreases, but the power output still increases. In this case, a slow increase in the turbine-side voltage (corresponding to...) is adopted. Figure 8 (Stage 5)

[0074] As the vertical axis wind turbine's speed gradually increases to point E (point E is the cut-out speed of the vertical axis wind turbine), the vertical axis wind turbine executes a shutdown command, and the turbine-side voltage immediately rises. As the speed decreases, the tip speed ratio continues to deviate. As the power coefficient decreases and the rotational speed gradually approaches 0, the mechanical brakes of the vertical axis wind turbine engage at point F. At this point, the vertical axis wind turbine shuts down to prevent overspeed. Figure 8 (Stage 6) Wait until the ambient wind speed drops below a safe level before starting the machine.

[0075] The resonant speed of the vertical axis wind turbine is set as Its resonant speed range is ,like Figure 7 As shown, the rotational speed of the vertical axis wind turbine is about to reach the resonance speed range (i.e., Figure 9 At point A in the diagram, increasing the voltage on the motor side causes the speed to decrease. After reaching point C, depending on the wind speed parameters at that time, it enters normal operation, maintaining or increasing the wind speed. The vertical axis wind turbine's speed will then rapidly increase to point D, thus crossing the resonance speed range (corresponding to...). Figure 9 (The curve segment ① in the middle).

[0076] When the vertical axis wind turbine's speed is close to reaching the resonance speed range A, and the wind speed is detected to be good, the voltage on the motor side is immediately reduced, allowing the vertical axis wind turbine to reach a higher speed, thus crossing the resonance speed range (corresponding to...). Figure 9 (Curve segment ② in the middle).

[0077] To perform the corresponding steps in the above embodiments and various possible methods, an implementation of the speed control device 200 is given below. Further, please refer to... Figure 10 , Figure 10 This is a functional block diagram of a speed control device 200 provided in an embodiment of the present invention. It should be noted that the speed control device 200 provided in this embodiment has the same basic principle and technical effects as the above embodiments. For the sake of brevity, any parts not mentioned in the embodiments of the present invention can be referred to the corresponding content in the above embodiments. The speed control device 200 includes: The acquisition module 201 is used to acquire the real-time rotational speed and tip speed ratio of the vertical axis wind turbine.

[0078] The control module 202 is used to adjust the motor-side load voltage of the vertical axis wind turbine according to the operating stage, real-time speed, tip speed ratio, and preset parameters calibrated from the tip speed ratio-power coefficient relationship curve of the vertical axis wind turbine, so as to control the speed of the vertical axis wind turbine. The speed of the vertical axis wind turbine is inversely correlated with the motor-side load voltage.

[0079] Optionally, the above modules can be stored in the form of software or firmware. Figure 1 The memory 110 shown is either stored in or embedded in the operating system (OS) of the control device 100, and can be used by... Figure 1 The processor 120 executes the program. Meanwhile, the data and program code required to execute the above modules can be stored in the memory 110.

[0080] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can also be implemented in other ways. The apparatus embodiments described above are merely illustrative; for example, the flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of apparatus, methods, and computer program products according to various embodiments of the present invention. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order than those marked in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in a block diagram and / or flowchart, and combinations of blocks in block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions.

[0081] In addition, the functional modules in the various embodiments of the present invention can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0082] If the aforementioned functions are implemented as software functional modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this invention, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0083] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A speed control method, characterized in that, A control device for a vertical axis wind turbine, the method comprising: Obtain the real-time rotational speed and tip speed ratio of the vertical axis wind turbine; Based on the operating stage of the vertical axis wind turbine, the real-time rotational speed, the tip speed ratio, and preset parameters calibrated from the tip speed ratio-power coefficient relationship curve corresponding to the vertical axis wind turbine, the motor-side load voltage of the vertical axis wind turbine is adjusted to control the rotational speed of the vertical axis wind turbine, wherein the rotational speed of the vertical axis wind turbine is inversely correlated with the motor-side load voltage.

2. The speed control method as described in claim 1, characterized in that, The preset parameters include a preset dead zone tip speed ratio range and a preset cut-out speed. The steps for adjusting the motor-side load voltage of the vertical axis wind turbine, based on the operating stage of the vertical axis wind turbine, the real-time speed, the tip speed ratio, and the preset parameters calibrated from the tip speed ratio-power coefficient relationship curve corresponding to the vertical axis wind turbine, include: When the operation phase is the self-starting phase, the load voltage on the motor side is adjusted according to the blade tip speed ratio and the preset dead zone blade tip speed ratio range so that the vertical axis wind turbine can start successfully. When the operation phase is the power generation phase, the wind speed change trend is obtained, and the load voltage on the motor side is adjusted according to the real-time rotational speed and the wind speed change trend to avoid resonance of the vertical axis wind turbine. When the operation phase is a shutdown phase, the load voltage on the motor side is adjusted according to the real-time rotational speed and the preset cut-out rotational speed to ensure safe braking of the vertical axis wind turbine.

3. The speed control method as described in claim 2, characterized in that, The step of adjusting the motor-side load voltage according to the tip speed ratio and the preset dead zone tip speed ratio range includes: If the tip speed ratio is greater than the upper limit of the preset dead zone tip speed ratio range, the load voltage on the motor side is reduced according to the first strategy to increase the rotational speed of the vertical axis wind turbine.

4. The speed control method as described in claim 2, characterized in that, The preset parameters also include a preset resonant speed, and the step of adjusting the motor-side load voltage according to the real-time speed and the wind speed change trend includes: If the wind speed change trend is a continuous increasing trend and the difference between the real-time rotational speed and the preset resonance rotational speed is less than the preset value, then the load voltage on the motor side is reduced according to the second strategy so that the rotational speed of the vertical axis wind turbine exceeds the resonance rotational speed range of the vertical axis wind turbine.

5. The speed control method as described in claim 4, characterized in that, The step of adjusting the motor-side load voltage according to the tip speed ratio and the wind speed change trend further includes: If the wind speed change trend is a continuous decreasing trend and the difference between the real-time rotational speed and the preset resonance rotational speed is less than the preset value, then the load voltage on the motor side is increased according to the third strategy so that the rotational speed of the vertical axis wind turbine exceeds the resonance rotational speed range of the vertical axis wind turbine.

6. The speed control method as described in claim 2, characterized in that, The preset parameters also include a preset effective tip speed ratio. The step of adjusting the motor-side load voltage of the vertical axis wind turbine, based on the operating stage of the vertical axis wind turbine, the real-time rotational speed, the tip speed ratio, and the preset parameters calibrated from the tip speed ratio-power coefficient relationship curve corresponding to the vertical axis wind turbine, further includes: When the operation phase is the power generation phase and the wind speed change trend is a stable fluctuation trend, the load voltage on the motor side is adjusted according to the difference between the tip speed ratio and the preset effective tip speed ratio, so that the tip speed ratio is within the fluctuation range corresponding to the preset effective tip speed ratio.

7. The speed control method as described in claim 2, characterized in that, The step of adjusting the motor-side load voltage based on the real-time rotational speed and the preset cut-out rotational speed includes: If the real-time rotational speed is greater than the preset cut-out rotational speed, the load voltage on the motor side is increased according to the fourth strategy to reduce the rotational speed of the vertical axis wind turbine to a preset safety threshold.

8. A speed control device, characterized in that, A control device for a vertical axis wind turbine, the device comprising: The acquisition module is used to acquire the real-time rotational speed and tip speed ratio of the vertical axis wind turbine. The control module is used to adjust the motor-side load voltage of the vertical axis wind turbine according to the operating stage of the vertical axis wind turbine, the real-time speed, the tip speed ratio, and preset parameters calibrated from the tip speed ratio-power coefficient relationship curve corresponding to the vertical axis wind turbine, so as to control the speed of the vertical axis wind turbine. The speed of the vertical axis wind turbine is inversely correlated with the motor-side load voltage.

9. A vertical axis wind turbine, characterized in that, The device includes a control unit comprising a processor and a memory, the memory storing machine-executable instructions executable by the processor, the processor executing the machine-executable instructions to implement the speed control method according to any one of claims 1-7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the speed control method as described in any one of claims 1-7.

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