Yaw control device and method for multi-rotor wind turbine

Abstract

A yaw control device and method for a multi-rotor wind turbine are provided. The yaw control device includes: a sensor for determining the yaw error of the multi-rotor wind turbine, the yaw error representing the angle between the forward and backward directions of the multi-rotor wind turbine and the wind direction; and a yaw controller configured to: in response to the yaw error being greater than a first preset threshold, determine a target pitch angle for each rotor in the multi-rotor system, and instruct the pitch mechanism of each rotor to adjust the pitch angle of the corresponding rotor to the target pitch angle of the corresponding rotor, so that the wind force acting on each rotor causes the multi-rotor wind turbine to produce a yaw action to reduce the yaw error.

Description

Technical Field

[0001] This application relates to the field of multi-rotor wind turbine control technology, and more specifically, to a yaw control device and method for a multi-rotor wind turbine. Background Technology

[0002] To enable yaw action in multi-rotor wind turbines (e.g., dual-rotor wind turbines), current solutions utilize motors connected to both sides of the yaw bearing via gears to provide yaw power. However, because multi-rotor wind turbines have a large mass mounted on the arms far from the central tower and yaw system, they require large motors and / or transmissions to handle the large moment of inertia. Furthermore, since the yaw system on a multi-rotor wind turbine needs to handle high torque, it has evolved into a large system, requiring the central tower to support numerous yaw motors and gear units or large motor / gear systems. This necessitates a large tower diameter for the multi-rotor wind turbine.

[0003] Clearly, current yaw control schemes, which employ large motors and / or transmission devices as well as large tower diameters, increase the manufacturing and / or yaw control costs of wind turbines. Therefore, there is an urgent need for a yaw control device and method that can reduce the manufacturing and / or yaw control costs of wind turbines. Summary of the Invention

[0004] The purpose of this invention is to provide a yaw control device and method for a multi-rotor wind turbine, so as to at least solve the problems in the above-mentioned related technologies, or it may not solve any of the above-mentioned problems.

[0005] According to one aspect of the embodiments of the present disclosure, a yaw control device for a multi-rotor wind turbine is provided, the yaw control device comprising: a sensor for determining a yaw error of the multi-rotor wind turbine, the yaw error representing the angle between the forward and backward directions of the multi-rotor wind turbine and the wind direction; and a yaw controller configured to: in response to the yaw error being greater than a first preset threshold, determine a target pitch angle for each rotor in the multi-rotor wind turbine, and instruct a pitch mechanism of each rotor to adjust the pitch angle of the corresponding rotor to the target pitch angle of the corresponding rotor, so that the wind force acting on each rotor causes the multi-rotor wind turbine to produce a yaw action for reducing the yaw error.

[0006] According to embodiments of this disclosure, by adjusting the rotor pitch angle, the wind force difference acting on multiple rotors provides the power for the wind turbine to yaw, which can reduce the requirements for the yaw motor, thereby reducing the requirements for the tower diameter, and thus reducing the construction and / or yaw control costs of the wind turbine.

[0007] Optionally, the yaw controller includes: a plurality of sub-yaw controllers corresponding to each rotor in the multi-rotor, wherein each sub-yaw controller independently determines the target pitch angle of the rotor corresponding to the sub-yaw controller.

[0008] Optionally, during the process of adjusting the pitch angle of each rotor to a target pitch angle corresponding to that rotor, different thrusts acting on the multiple rotors provide the power to generate the yaw action.

[0009] Optionally, the multi-rotor wind turbine is a dual-rotor wind turbine, wherein the yaw controller is configured to: increase the current pitch angle of one rotor of the dual rotors by a second preset threshold at predetermined intervals, and decrease the current pitch angle of the other rotor of the dual rotors by a third preset threshold.

[0010] Optionally, the multi-rotor wind turbine is a dual-rotor wind turbine, wherein the yaw controller is configured to determine the target pitch angle of each rotor based on the yaw error and the feedback gain of the yaw error, wherein the feedback gain is determined based on the pitch angle of each rotor in the dual rotor, the rotational speed of each rotor in the dual rotor, and the wind speed.

[0011] Optionally, the target pitch angle of one rotor in the dual-rotor configuration is the current pitch angle of that rotor plus Δβ1, and the target pitch angle of the other rotor in the dual-rotor configuration is the current pitch angle of that other rotor minus Δβ2.

[0012] Among them, △β1=α1·G(OP)·Ψ error △β2=α2·G(OP)·Ψ error ,

[0013] Where α1 and α2 are preset values ​​and satisfy α1 + α2 = 1, G(OP) is the feedback gain, and Ψ error The yaw error is described above.

[0014] Optionally, the multi-rotor wind turbine is a dual-rotor wind turbine, wherein the yaw controller is configured to adjust the target pitch angle of each rotor using a preset number of time intervals, wherein the target pitch angle of each rotor corresponding to each time interval is predetermined based on an optimization strategy, wherein the optimization strategy minimizes the sum of squares of the yaw errors corresponding to each time interval, wherein the yaw error corresponding to each time interval indicates the yaw error after each rotor is adjusted to the target pitch angle corresponding to each time interval.

[0015] According to another aspect of the embodiments of this disclosure, a yaw control method for a multi-rotor wind turbine is provided. The yaw control method includes: determining a yaw error of the multi-rotor wind turbine using a sensor, the yaw error representing the angle between the forward and backward directions of the multi-rotor wind turbine and the wind direction; in response to the yaw error being greater than a first preset threshold, determining a target pitch angle for each rotor in the multi-rotor wind turbine by a yaw controller, and instructing the pitch mechanism of each rotor to adjust the pitch angle of the corresponding rotor to the target pitch angle of the corresponding rotor, so that the wind force acting on each rotor causes the multi-rotor wind turbine to produce a yaw action to reduce the yaw error.

[0016] Optionally, the yaw controller includes a plurality of sub-yaw controllers corresponding to each rotor in the multi-rotor system, wherein the step of determining the target pitch angle of each rotor in the multi-rotor system includes: each sub-yaw controller independently determining the target pitch angle of the rotor corresponding to that sub-yaw controller.

[0017] Optionally, during the process of adjusting the pitch angle of each rotor to a target pitch angle corresponding to that rotor, different thrusts acting on the multiple rotors provide the power to generate the yaw action.

[0018] Optionally, the multi-rotor wind turbine is a dual-rotor wind turbine, wherein the step of determining the target pitch angle of each rotor in the multi-rotor includes: increasing the current pitch angle of one rotor in the dual rotor by a second preset threshold at predetermined intervals, and decreasing the current pitch angle of the other rotor in the dual rotor by a third preset threshold.

[0019] Optionally, the multi-rotor wind turbine is a dual-rotor wind turbine, wherein the step of determining the target pitch angle of each rotor in the multi-rotor includes: determining the target pitch angle of each rotor based on the yaw error and the feedback gain of the yaw error, wherein the feedback gain is determined according to the pitch angle of each rotor in the dual rotor, the rotational speed of each rotor in the dual rotor, and the wind speed.

[0020] Optionally, the target pitch angle of one rotor in the dual-rotor configuration is the current pitch angle of that rotor plus Δβ1, and the target pitch angle of the other rotor in the dual-rotor configuration is the current pitch angle of that other rotor minus Δβ2.

[0021] Among them, △β1=α1·G(OP)·Ψ error △β2=α2·G(OP)·Ψ error ,

[0022] Where α1 and α2 are preset values ​​and satisfy α1 + α2 = 1, G(OP) is the feedback gain, and Ψ errorThe yaw error is described above.

[0023] Optionally, the multi-rotor wind turbine is a dual-rotor wind turbine, wherein the step of determining the target pitch angle of each rotor in the multi-rotor includes: adjusting the target pitch angle of each rotor using a preset number of time intervals, wherein the target pitch angle of each rotor corresponding to each time interval is predetermined based on an optimization strategy, wherein the optimization strategy minimizes the sum of squares of the yaw errors corresponding to each time interval, wherein the yaw error corresponding to each time interval indicates the yaw error after each rotor is adjusted to the target pitch angle corresponding to each time interval.

[0024] According to another aspect of the embodiments of this disclosure, a yaw control device for a multi-rotor wind turbine is provided, characterized in that the yaw control device includes: a processor; and a memory storing a computer program that executes the yaw control method as described above when run by the processor.

[0025] According to an embodiment of this disclosure, a multi-rotor wind turbine is provided, characterized in that the multi-rotor wind turbine includes: at least two rotors, a sensor, a yaw controller, a processor, and a memory, wherein the memory stores a computer program that executes the yaw control method as described above when run by the processor.

[0026] According to another aspect of the embodiments of the present disclosure, a computer-readable storage medium storing a computer program is provided, wherein the computer program, when executed by a processor, implements the yaw control method as described above. Attached Figure Description

[0027] The above and other objects and features of the invention will become clearer from the following description taken in conjunction with the accompanying drawings, which exemplarily illustrate embodiments of the invention, wherein:

[0028] Figure 1 This is a schematic diagram illustrating an example of a multi-rotor wind turbine;

[0029] Figure 2 It is shown Figure 1 A top view of the dual-rotor wind turbine shown;

[0030] Figure 3 This is a diagram illustrating the structure of a yaw control device 300 for a multi-rotor wind turbine according to an embodiment of the present disclosure;

[0031] Figure 4 This is a schematic diagram illustrating a yaw control system for a dual-rotor wind turbine according to an embodiment of the present disclosure; and

[0032] Figure 5This is a flowchart illustrating a yaw control method for a dual-rotor wind turbine according to an embodiment of the present disclosure. Detailed Implementation

[0033] In the following description, various embodiments of the present disclosure are illustrated with reference to the accompanying drawings, wherein the same reference numerals are used to denote the same or similar elements, features, and structures. However, the present disclosure is not intended to be limited to the specific embodiments described herein, and it is intended that the present disclosure cover all modifications, equivalents, and / or substitutions of the present disclosure, provided they fall within the scope of the appended claims and their equivalents. The terms and words used in the following description and claims are not limited to their dictionary meanings, but are used only to enable a clear and consistent understanding of the present disclosure. Therefore, it will be apparent to those skilled in the art that the following description of various embodiments of the present disclosure is for illustrative purposes only and is not intended to limit the purpose of the present disclosure as defined by the appended claims and their equivalents.

[0034] It should be understood that, unless the context clearly indicates otherwise, the singular form includes the plural form. The terms “comprising,” “including,” and “having” as used herein indicate the presence of a disclosed function, operation, or element, but do not exclude other functions, operations, or elements.

[0035] For example, the expression “A or B” or “at least one of A and / or B” can indicate A and B, or A or B. For example, the expression “A or B” or “at least one of A and / or B” can indicate (1) A, (2) B or (3) both A and B.

[0036] In various embodiments of this disclosure, it is intended that when a component (e.g., a first component) is referred to as being "coupled" or "connected" to, or being "coupled" or "connected" to, another component (e.g., a second component), the component may be directly connected to, or may be connected via, another component (e.g., a third component). Conversely, when a component (e.g., a first component) is referred to as being "directly coupled" or "directly connected" to, or being directly coupled to or directly connected to, another component (e.g., a second component), there is no other component (e.g., a third component) between the component and the other component.

[0037] The expression “configured as” used in describing the various embodiments of this disclosure may be used interchangeably, for example, with expressions such as “suitable for,” “capable of,” “designed to,” “suitable for,” “manufactured as,” and “capable,” depending on the context. The term “configured as” may not necessarily indicate that the hardware is “specifically designed for.” Rather, in some cases, the expression “a device configured as…” may indicate that the device and another device or portion are “capable of….” For example, the expression “a processor configured to perform A, B, and C” may indicate a dedicated processor (e.g., an embedded processor) for performing the respective operations or a general-purpose processor (e.g., a central processing unit CPU or application processor (AP)) for performing the respective operations by executing at least one software program stored in a memory device.

[0038] The terminology used herein is intended to describe certain embodiments of this disclosure but is not intended to limit the scope of other embodiments. Unless otherwise indicated herein, all terms used herein (including technical or scientific terms) are to have the same meaning as commonly understood by one of ordinary skill in the art. Generally, terms as defined in dictionaries should be considered to have the same meaning as in the context of the relevant art and should not be interpreted differently or as having an overly formal meaning unless expressly defined herein. In no event should the terminology defined in this disclosure be construed as excluding embodiments of this disclosure.

[0039] Figure 1 This is a schematic diagram illustrating an example of a multi-rotor wind turbine.

[0040] Reference Figure 1 , Figure 1 The multi-rotor wind turbine shown is a dual-rotor wind turbine. The twin wind turbine 100 may include a first rotor 111 and a second rotor 112, a tower 120, and a crossbeam 130. The first rotor 111 and the second rotor 112 are mounted at both ends of the crossbeam 130 and supported by the tower 120. It is understood that the crossbeam may not only consist of a single beam but may also be a triangular beam structure; this application does not specifically limit this. Furthermore, the principle of more complex dual-rotor wind turbines with related structures is also encompassed by the principles described herein. Figure 1 The principle of the schematic diagram is described below, without making specific limitations here.

[0041] Those skilled in the art should understand that the multi-rotor wind turbine in this disclosure may also be a wind turbine that includes other numbers of rotors (e.g., 3 rotors, 4 rotors, 6 rotors, etc.), and each rotor of the multi-rotor wind turbine may include, for example, 2, 3 or 4 wind turbine blades.

[0042] Figure 2 It is shown Figure 1 The image shows a top view of a dual-rotor wind turbine.

[0043] Reference Figure 2 The A and B axes indicate the wind direction and form a wind direction coordinate system with the direction perpendicular to the wind direction. The C and D axes represent the wind turbine coordinate system with the forward and backward directions of the multi-rotor wind turbine and the direction perpendicular to the forward and backward directions. Due to changes in wind direction or changes in the forward and backward directions of the wind turbine (e.g., changes in the forward and backward directions of the wind turbine caused by yaw of the wind turbine), the wind direction and the forward and backward directions of the wind turbine are inconsistent, resulting in a yaw error Ψ. error , which is the angle between the forward and backward direction of the wind turbine and the wind direction.

[0044] Due to the presence of yaw error, the wind force F acting on the two rotors (or rotor nacelle unit (RNA)) thrust,1 (i.e., the thrust of the wind acting on the first rotor) and F thrust,2 (That is, the thrust of the wind acting on the first rotor) generates a yaw moment M at the point between the beam and the tower. yaw Because of M yaw The existence of M yaw This will cause stress on the wind turbine, therefore, it is necessary to minimize the yaw error Ψ. error To eliminate yaw moment, existing technologies use a yaw motor to provide power for yaw, thereby reducing the yaw error Ψ. error In other words, the forward and backward orientation of the wind turbine should be aligned with the wind direction. Clearly, this is to induce a yaw action in the wind turbine to reduce Ψ. error It requires an electric motor to provide power.

[0045] Based on this, this application provides a yaw control device for a multi-rotor wind turbine, which can achieve yaw control without requiring a yaw motor to provide power. error Reduced yaw motion, or compared to existing technologies, requiring only a smaller yaw motor to provide power.

[0046] Figure 3 This is a diagram illustrating the structure of a yaw control device 300 for a multi-rotor wind turbine according to an embodiment of the present disclosure.

[0047] Reference Figure 3 The yaw control device 300 may include a sensor 301 and a yaw controller 302. Those skilled in the art will understand that the yaw control device 300 may also include other components, and at least one of the components included in the yaw control device 300 may be omitted, combined, or separated.

[0048] Reference Figure 3The sensor 300 is used to determine the yaw error of the multi-rotor wind turbine, which represents the angle between the forward and backward direction of the multi-rotor wind turbine and the wind direction.

[0049] As an example, yaw error can be obtained directly from sensor 300. For instance, it can be based on measurements from a wind vane or radar installed in the nacelle, since they are oriented in a direction perpendicular to the rotor plane. When the wind direction changes, the direction perpendicular to the rotor plane changes due to the wind pushing the turbine, and the changed direction perpendicular to the rotor plane can indicate the yaw error.

[0050] As an example, yaw error can be calculated by sensors based on data sensed by the sensors (e.g., wind direction, turbine forward / backward direction, and / or turbine yaw angle). For instance, the yaw error can be determined by comparing the wind direction measured at a measurement mast location near the wind turbine with the measured yaw direction of the turbine.

[0051] As an example, yaw error can also be obtained by the yaw controller 302 based on the sensing data from the sensor 300.

[0052] The yaw controller 300 can be configured to: in response to the yaw error being greater than a first preset threshold, determine the target pitch angle of each rotor in the multi-rotor system, and instruct the pitch mechanism of each rotor to adjust the pitch angle of the corresponding rotor to the target pitch angle of the corresponding rotor, so that the wind force acting on each rotor causes the multi-rotor wind turbine to produce a yaw action to reduce the yaw error.

[0053] Those skilled in the art will understand that the target pitch angle can indicate the total pitch angle of the rotor or the pitch angle of each blade of the rotor. For example, for a rotor with three blades, the target pitch angle of the first rotor may include three components corresponding to the three blades of the first rotor respectively. and The target pitch angle of the second rotor may include three components corresponding to the three blades of the second rotor. and

[0054] Those skilled in the art will understand that the wind thrust acting on the rotor varies with the rotor's pitch angle. Therefore, by changing the pitch angle of each rotor in a multi-rotor wind turbine, the wind thrust acting on different rotors can be made different. This difference in wind thrust acting on each rotor can provide the power to generate yaw action, which will result in a yaw error Ψ. error Decrease.

[0055] The specific methods for adjusting the rotor's pitch angle to the target pitch angle through the pitch mechanism can be achieved in various ways, which will not be elaborated here.

[0056] As an example, the yaw controller 300 may include a plurality of sub-yaw controllers corresponding to each of the multiple rotors, wherein each sub-yaw controller is configured to independently determine the target pitch angle of the rotor corresponding to the sub-yaw controller.

[0057] Specifically, taking a dual-rotor wind turbine as an example, the sub-yaw controller corresponding to the first rotor 111 determines the target pitch angle of the first rotor 111 based on the yaw error obtained by the sensor and instructs the corresponding pitch actuator of the first rotor 111 to perform pitch control based on the target pitch angle. The sub-yaw controller corresponding to the second rotor 112 determines the target pitch angle of the second rotor 112 based on the yaw error obtained by the sensor and instructs the corresponding pitch actuator of the second rotor 112 to perform pitch control based on the target pitch angle.

[0058] As an example, during the process of adjusting the pitch angle of each rotor to a target pitch angle corresponding to that rotor, different thrust levels acting on the multiple rotors provide the power to generate the yaw action.

[0059] Since the wind thrust on the rotor is related to the rotor's pitch angle, the difference in wind thrust between the rotors can provide the power to generate yaw by adjusting the rotor's pitch angle through the pitch actuator.

[0060] Figure 4 This is a schematic diagram illustrating a yaw control system for a dual-rotor wind turbine according to an embodiment of the present disclosure.

[0061] Reference Figure 4 The first yaw controller 402 determines the target pitch angle of the first rotor based on the sensing data from the sensor 401, and instructs the pitch actuator 404 of the first rotor to perform pitch control based on the target pitch angle. The first yaw controller 403 determines the target pitch angle of the second rotor based on the sensing data from the sensor 401, and instructs the pitch actuator 405 of the second rotor to perform pitch control based on the target pitch angle. By performing pitch control based on the determined target pitch angle, the thrust difference of the wind force acting on the dual rotors provides the power to generate yaw action, thereby producing a yaw action that reduces yaw error.

[0062] Those skilled in the art will understand that for wind turbines with other numbers of rotors (e.g., 4, 6, etc.), the structure and control process of the yaw control device are similar to those of a dual-rotor wind turbine. For example, for a four-rotor wind turbine, it may include four yaw controllers and four pitch actuators corresponding to the four rotors respectively.

[0063] As an example, when the multi-rotor wind turbine is a dual-rotor wind turbine, the yaw controller 302 can be configured to: increase the current pitch angle of one rotor in the dual rotors by a second preset threshold at predetermined intervals, and decrease the current pitch angle of the other rotor in the dual rotors by a third preset threshold, until the yaw error is not greater than a first preset threshold. The second and third preset thresholds can be the same or different. As described above, if the yaw error is greater than the first preset threshold, the rotor's pitch angle is adjusted at predetermined intervals until the yaw error is not greater than the first preset threshold.

[0064] As an example, the length of the scheduled time (or scheduled time period) can be a preset value.

[0065] Refer again Figure 2 The direction of increase in yaw error is clockwise. If F thrust1 >F thrust2 Then a positive yaw moment M is obtained. yaw This also means that the thrust difference ΔF under these circumstances thrust =F thurst1 -F thrust2 >0.

[0066] The thrust of the wind on each rotor is related to the rotor's pitch angle (e.g., the total pitch angle β of the first rotor). col,1 The total pitch angle β of the second rotor col,2 Therefore, the thrust difference can be changed by adjusting the pitch angle of each rotor, and the changed thrust difference can provide the power to generate yaw action.

[0067] As an example, if the yaw error Ψ error >Ψ min And △F thrust If <0, then use step size β s1 Increase β col,1 (soon beta) col,1 Decrease β s1 (as the target pitch angle of the first rotor), and with a step size β s2 Decrease β col,2 (soon beta) col,2 Decrease β s2 (as the target pitch angle of the second rotor); if the yaw error Ψ error <-Ψ min And △F thrust If the value is greater than 0, then the step size β is used. s1 Decrease β col,1 and with step size β s2 Increase β col,2 If -Ψ min ≤Ψ error ≤Ψ min Then β remains unchanged.col,1 and β col,2 , where step size β s1 and β s2 It can be predetermined through repeated trials or experience, Ψ min This is a preset threshold. As an example, β... s1 and β s2 The pitch angle can be the same or different. That is, if the yaw error exceeds the preset range that can be allowed, the rotor's pitch angle is adjusted. Specifically, the rotor's pitch angle can be increased or decreased at different or the same preset increments at each time interval, thereby using the thrust difference acting on the rotor to achieve yaw and reduce the yaw error to no more than the preset range that can be allowed.

[0068] Those skilled in the art will understand that the control frequency corresponding to this algorithm is slower than the sampling time of a normal controller, for example, operating at 1 Hz.

[0069] Those skilled in the art will understand that the yaw controller 302 may include a first yaw controller corresponding to the first rotor and a second yaw controller corresponding to the second rotor. In this case, the first yaw controller and the second yaw controller independently determine β based on the method described above. col,1 and β col,2 .

[0070] Those skilled in the art should understand that the method for determining the target pitch angle of the rotor based on a preset threshold cannot exceed the range determined by the maximum and minimum allowable pitch angles of the rotor. If the determined target pitch angle is greater than the range, then the target pitch angle is determined to be the maximum or minimum allowable pitch angle.

[0071] For example, if the target pitch angle of the rotor is determined to be greater than the maximum value, then the maximum value is used as the target pitch angle of the rotor; if the target pitch angle of the rotor is determined to be less than the minimum allowable value, then the minimum value is used as the target pitch angle of the rotor.

[0072] As an example, for a dual-rotor wind turbine, the yaw controller 302 can be configured to determine a target pitch angle for each rotor based on the yaw error and a feedback gain of the yaw error, wherein the feedback gain is determined based on the pitch angle of each rotor in the dual rotor, the rotational speed of each rotor in the dual rotor, and the wind speed.

[0073] As an example, the target pitch angle of one rotor in the dual-rotor configuration is the current pitch angle of that rotor plus Δβ1, and the target pitch angle of the other rotor in the dual-rotor configuration is the current pitch angle of that other rotor minus Δβ2.

[0074] Among them, △β1=α1·G(OP)·Ψ error△β2=α2·G(OP)·Ψ error ,

[0075] Where α1 and α2 are preset values ​​and satisfy α1 + α2 = 1, G(OP) is the feedback gain, and Ψ error The yaw error is described above.

[0076] G(OP) can be predetermined by design, for example, through simulation in aeroelastic code. Those skilled in the art will understand that the yaw controller 302 may include a first yaw controller corresponding to the first rotor and a second yaw controller corresponding to the second rotor. In this case, the first yaw controller and the second yaw controller independently determine β based on the method described above. col,1 and β col,2 .

[0077] As an example, α1 = α2 = 1 / 2.

[0078] As an example, α1 and α2 can also be different values, in which case the increase and decrease in pitch angle may be different.

[0079] Those skilled in the art should understand that the target pitch angle of the rotor determined based on the above feedback control method cannot exceed the range determined by the maximum and minimum allowable pitch angles of the rotor. If the determined target pitch angle is greater than the range, then the target pitch angle is determined to be the maximum or minimum allowable pitch angle.

[0080] For example, if the target pitch angle of the rotor is determined to be greater than the maximum value, then the maximum value is used as the target pitch angle of the rotor; if the target pitch angle of the rotor is determined to be less than the minimum allowable value, then the minimum value is used as the target pitch angle of the rotor.

[0081] As an example, for a dual-rotor wind turbine, the yaw controller 302 is configured to adjust the target pitch angle of each rotor using a preset number of time intervals, wherein the target pitch angle of each rotor corresponding to each time interval is predetermined based on an optimization strategy, wherein the optimization strategy minimizes the sum of squares of the yaw errors corresponding to each time interval, wherein the yaw errors corresponding to each time interval indicate the yaw error after each rotor is adjusted to the target pitch angle corresponding to each time interval.

[0082] As an example, the length of the time interval can be a preset value or can be determined according to preset rules.

[0083] As an example, a model-based optimization strategy can be used to determine the target pitch angle for each rotor. Specifically, the yaw acceleration can be expressed as:

[0084]

[0085] Among them, F Thrust () represents the thrust difference acting on the rotor, L is the arm length (distance between the two rotors), J is the moment of inertia of the yaw body, and β col1 (t), β col 、2(、t)v w (t)ω1(t)ω2(t) represent the pitch angle of the first rotor, the pitch angle of the second rotor, the wind speed, the rotational speed of the first rotor, and the rotational speed of the second rotor at time t, respectively.

[0086] Based on Equation 2), Ψ(t) can be calculated, which is the yaw angle of the wind turbine (indicating the forward and backward direction of the wind turbine).

[0087] Then, through optimization, the cost function ∫ t＝0…T (Ψ(t)-W dir (t)) 2 The value of dt is minimized, thus determining F. Thrust (), where W dir (t) represents the wind direction angle, therefore Ψ(t)-W dir (t) indicates yaw error.

[0088] Convert equation 2) into discrete form:

[0089]

[0090] Where, β min1 [n]<β col,1 [n]<β max1 [n] and β min2 [n]<β col,2 [n]<β max2 [n], where β min1 [n]β max1 [n] represent the minimum and maximum allowable target pitch angles of the first rotor, respectively, β min2 [n] and β max2 [n] represent the minimum and maximum allowable target pitch angles of the second rotor, respectively, β col1 [n]、β col2 [n]、v w [n], ω1[n], and ω2[n] represent the pitch angle of the first rotor, the pitch angle of the second rotor, the wind speed, the rotational speed of the first rotor, and the rotational speed of the second rotor, respectively, corresponding to the nth time step.

[0091] F Thrust (β col1 [n],β col2 [n],v w[n], ω1[n], ω2[n]) can be obtained from the first-principles model, which is a mixture of input variables because it represents the mapping from input variables to thrust differences, where the input variables are measurements.

[0092] Based on Equation 3, the yaw error for the next controller time step can be calculated using the yaw error and thrust difference corresponding to the current controller time step (i.e., the controller's sampling time).

[0093] For example, if the yaw error is adjusted through N controller time steps (or time intervals), then the yaw error corresponding to each time step should satisfy a condition that makes the discrete cost function... Minimize. Using this optimization strategy, F for each time step can be determined. Thrust (β col1 [n],β col2 [n],v w [n],ω1[n],ω2[n]), that is, the total pitch angle β of each rotor corresponding to each time step is determined. col1 [n] and β col2 [n], because, F Thrust (β col1 [n],β col2 [n],v w [n],ω1[n],ω2[n]) and β col1 [n] and β col2 [n] corresponds to.

[0094] As an example, the time step or time interval length is a preset value.

[0095] By using a model-based optimization strategy to determine the number N of adjustment steps for the yaw angle and the total pitch angle of each rotor corresponding to each controller time step, the total pitch angle of each rotor can be gradually adjusted using the determined number N of adjustment steps and the total pitch angle of each rotor corresponding to each controller time step to perform pitch control, thereby using wind force difference to achieve yaw of the wind turbine.

[0096] Those skilled in the art will understand that the yaw controller 302 may include a first yaw controller corresponding to the first rotor and a second yaw controller corresponding to the second rotor. In this case, the first yaw controller and the second yaw controller independently determine β based on the method described above. col1 [n] and β col2 [n].

[0097] Preferably, the yaw control scheme provided by the present invention can be used in low wind speed scenarios or slow unloading scenarios. Those skilled in the art should understand that the yaw control scheme provided by the present invention can also be used in other scenarios (e.g., high wind speed scenarios).

[0098] As an example, if adjusting the rotor's pitch angle is still insufficient to provide the power required for yaw, the power generated by the motor can be further utilized to produce the yaw action. That is, yaw is performed based on the thrust difference of the wind acting on the rotor and the yaw power provided by the motor. Since the power for yaw is provided by adjusting the rotor's pitch angle, this application requires less motor power compared to existing technologies. This reduces the mass and size of the yaw system, while also lowering the requirements for the tower diameter, thereby saving on construction and / or yaw control costs.

[0099] Reference above Figures 1 to 4 A yaw control device for a multi-rotor wind turbine according to an embodiment of the present disclosure has been described below, with reference to... Figure 5 A yaw control method according to embodiments of the present disclosure will be described.

[0100] Figure 5 This is a flowchart illustrating a yaw control method for a multi-rotor wind turbine according to an embodiment of the present disclosure.

[0101] Reference Figure 5 In step 501, the yaw error of the multi-rotor wind turbine is determined by a sensor. The yaw error represents the angle between the forward and backward direction of the multi-rotor wind turbine and the wind direction.

[0102] In step 502, in response to the yaw error being greater than a first preset threshold, the yaw controller determines the target pitch angle of each rotor in the multi-rotor system and instructs the pitch mechanism of each rotor to adjust the pitch angle of the corresponding rotor to the target pitch angle of the corresponding rotor, so that the wind force acting on each rotor causes the multi-rotor wind turbine to generate a yaw action to reduce the yaw error.

[0103] As an example, the yaw controller includes a plurality of sub-yaw controllers corresponding to each of the multi-rotor rotors, wherein the step of determining the target pitch angle of each rotor in the multi-rotor rotors includes: each sub-yaw controller independently determining the target pitch angle of the rotor corresponding to that sub-yaw controller.

[0104] As an example, during the process of adjusting the pitch angle of each rotor to a target pitch angle corresponding to that rotor, the different thrusts acting on the multiple rotors provide the power to generate the yaw action.

[0105] As an example, the multi-rotor wind turbine is a dual-rotor wind turbine, wherein the step of determining the target pitch angle of each rotor in the multi-rotor includes: increasing the current pitch angle of one rotor in the dual rotor by a second preset threshold at predetermined intervals, and decreasing the current pitch angle of the other rotor in the dual rotor by a third preset threshold.

[0106] As an example, the multi-rotor wind turbine is a dual-rotor wind turbine, wherein the step of determining the target pitch angle of each rotor in the multi-rotor includes: determining the target pitch angle of each rotor based on the yaw error and the feedback gain of the yaw error, wherein the feedback gain is determined according to the pitch angle of each rotor in the dual rotor, the rotational speed of each rotor in the dual rotor, and the wind speed.

[0107] As an example, the target pitch angle of one rotor in the dual-rotor configuration is the current pitch angle of that rotor plus Δβ1, and the target pitch angle of the other rotor in the dual-rotor configuration is the current pitch angle of that other rotor minus Δβ2.

[0108] Among them, △β1=α1·G(OP)·Ψ error △β2=α2·G(OP)·Ψ error ,

[0109] Where α1 and α2 are preset values ​​and satisfy α1 + α2 = 1, G(OP) is the feedback gain, and Ψ error The yaw error is described above.

[0110] As an example, the multi-rotor wind turbine is a dual-rotor wind turbine, wherein the step of determining the target pitch angle of each rotor in the multi-rotor includes: adjusting the target pitch angle of each rotor using a preset number of time intervals, wherein the target pitch angle of each rotor corresponding to each time interval is predetermined based on an optimization strategy, wherein the optimization strategy minimizes the sum of squares of the yaw errors corresponding to each time interval, wherein the yaw errors corresponding to each time interval indicate the yaw error after each rotor is adjusted to the target pitch angle corresponding to each time interval.

[0111] According to an embodiment of the present disclosure, a yaw control device for a multi-rotor wind turbine is provided, characterized in that the yaw control device includes: a processor; and a memory storing a computer program that, when run by the processor, executes the yaw control method as described herein.

[0112] According to an embodiment of this disclosure, a multi-rotor wind turbine is provided, characterized in that the multi-rotor wind turbine includes: at least two rotors, a sensor, a yaw controller, a processor, and a memory, wherein the memory stores a computer program that executes the yaw control method as described herein when run by the processor.

[0113] According to embodiments of the present disclosure, a computer-readable storage medium storing a computer program is provided, wherein when the computer program is executed by a processor, it implements the yaw control method as described herein.

[0114] According to embodiments of this disclosure, a computer-readable storage medium storing instructions may also be provided, wherein when the instructions are executed by at least one processor, they cause at least one processor to perform a yaw control method according to this disclosure. Examples of computer-readable storage media herein include: read-only memory (ROM), random access programmable read-only memory (PROM), electrically erasable programmable read-only memory (EEPROM), random access memory (RAM), dynamic random access memory (DRAM), static random access memory (SRAM), flash memory, non-volatile memory, CD-ROM, CD-R, CD+R, CD-RW, CD+RW, DVD-ROM, DVD-R, DVD+R, DVD-RW, DVD+RW, DVD-RAM, BD-ROM, BD-R, BD-R LTH, BD-RE, Blu-ray or optical disc storage, hard disk drive (HDD), solid-state drive (SSD), card storage (such as multimedia cards, secure digital (SD) cards, or ultra-fast digital (XD) cards), magnetic tape, floppy disk, magneto-optical data storage device, optical data storage device, hard disk, solid-state drive, and any other device configured to store a computer program and any associated data, data files, and data structures in a non-transitory manner and to provide the computer program and any associated data, data files, and data structures to a processor or computer so that the processor or computer can execute the computer program. The computer program in the aforementioned computer-readable storage medium can run in an environment deployed in computer devices such as clients, hosts, agent devices, servers, etc. Furthermore, in one example, the computer program and any associated data, data files, and data structures are distributed across a networked computer system, such that the computer program and any associated data, data files, and data structures are stored, accessed, and executed in a distributed manner through one or more processors or computers.

[0115] According to embodiments of this disclosure, a computer program product may also be provided, wherein instructions in the computer program product are executable by a processor of a computer device to perform the yaw control method described herein.

[0116] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this disclosure are indicated by the following claims.

Claims

1. A yaw control device for a multi-rotor wind turbine, characterized in that, The yaw control device includes: A sensor is used to determine the yaw error of the multi-rotor wind turbine, the yaw error representing the angle between the forward and backward directions of the multi-rotor wind turbine and the wind direction; The yaw controller is configured as follows: In response to the yaw error exceeding a first preset threshold, a target pitch angle is determined for each rotor in the multi-rotor system, and the pitch mechanism of each rotor is instructed to adjust the pitch angle of the corresponding rotor to the target pitch angle, so that the wind force acting on each rotor causes the multi-rotor wind turbine to produce a yaw action to reduce the yaw error. The multi-rotor wind turbine is a dual-rotor wind turbine, wherein the yaw controller is configured as follows: The target pitch angle of each rotor is determined based on the yaw error and the feedback gain of the yaw error, wherein the feedback gain is determined based on the pitch angle of each rotor in the dual rotor, the rotational speed of each rotor in the dual rotor, and the wind speed.

2. The yaw control device as described in claim 1, characterized in that, The yaw controller includes: a plurality of sub-yaw controllers corresponding to each rotor in the multi-rotor system. Each sub-yaw controller is configured to independently determine the target pitch angle of the rotor corresponding to that sub-yaw controller.

3. The yaw control device as described in claim 2, characterized in that, As the pitch angle of each rotor is adjusted to a target pitch angle corresponding to that rotor, the different thrusts acting on the multiple rotors provide the power to generate the yaw action.

4. The yaw control device according to any one of claims 1-3, characterized in that, The multi-rotor wind turbine is a dual-rotor wind turbine. The yaw controller is configured to: increase the current pitch angle of one rotor of the dual rotors by a second preset threshold at predetermined intervals, and decrease the current pitch angle of the other rotor of the dual rotors by a third preset threshold.

5. The yaw control device as described in claim 1, wherein, The target pitch angle of one of the dual rotors is the current pitch angle of that rotor plus... The target pitch angle of the other rotor in the dual-rotor configuration is the current pitch angle of the other rotor minus... , in, , , in, It is a preset value and satisfies , The feedback gain, The yaw error is described above.

6. The yaw control device according to any one of claims 1-3, characterized in that, in, The yaw controller is also configured to adjust the target pitch angle of each rotor using a preset number of time intervals. The target pitch angle of each rotor corresponding to each time interval is predetermined based on an optimization strategy, wherein the optimization strategy minimizes the sum of squares of the yaw error corresponding to each time interval, wherein the yaw error corresponding to each time interval indicates the yaw error after each rotor is adjusted to the target pitch angle corresponding to each time interval.

7. A yaw control method for a multi-rotor wind turbine, characterized in that, The yaw control method includes: The yaw error of the multi-rotor wind turbine is determined by a sensor, and the yaw error represents the angle between the forward and backward direction of the multi-rotor wind turbine and the wind direction. In response to the yaw error exceeding a first preset threshold, the yaw controller determines the target pitch angle for each rotor in the multi-rotor system and instructs the pitch mechanism of each rotor to adjust the pitch angle of the corresponding rotor to the target pitch angle, so that the wind force acting on each rotor causes the multi-rotor wind turbine to generate a yaw action to reduce the yaw error. The multi-rotor wind turbine is a dual-rotor wind turbine. The step of determining the target pitch angle for each rotor in the multi-rotor configuration includes: The target pitch angle of each rotor is determined based on the yaw error and the feedback gain of the yaw error, wherein the feedback gain is determined based on the pitch angle of each rotor in the dual rotor, the rotational speed of each rotor in the dual rotor, and the wind speed.

8. The yaw control method as described in claim 7, characterized in that, The yaw controller includes multiple sub-yaw controllers corresponding to each rotor in the multi-rotor system. The step of determining the target pitch angle of each rotor in the multi-rotor system includes: each sub-yaw controller independently determining the target pitch angle of the rotor corresponding to that sub-yaw controller.

9. The yaw control method as described in claim 8, characterized in that, As the pitch angle of each rotor is adjusted to a target pitch angle corresponding to that rotor, the different thrusts acting on the multiple rotors provide the power to generate the yaw action.

10. The yaw control method according to any one of claims 7-9, characterized in that, The multi-rotor wind turbine is a dual-rotor wind turbine. The step of determining the target pitch angle of each rotor in the multi-rotor system includes: increasing the current pitch angle of one rotor in the dual rotor system by a second preset threshold at predetermined intervals, and decreasing the current pitch angle of the other rotor in the dual rotor system by a third preset threshold.

11. The yaw control method as described in claim 7, wherein, The target pitch angle of one of the dual rotors is the current pitch angle of that rotor plus... The target pitch angle of the other rotor in the dual-rotor configuration is the current pitch angle of the other rotor minus... , in, , , in, It is a preset value and satisfies , The feedback gain, The yaw error is described above.

12. The yaw control method according to any one of claims 7-9, characterized in that, The step of determining the target pitch angle of each rotor in the multi-rotor configuration further includes: adjusting the target pitch angle of each rotor using a preset number of time intervals. The target pitch angle of each rotor corresponding to each time interval is predetermined based on an optimization strategy, wherein the optimization strategy minimizes the sum of squares of the yaw error corresponding to each time interval, wherein the yaw error corresponding to each time interval indicates the yaw error after each rotor is adjusted to the target pitch angle corresponding to each time interval.

13. A yaw control device for a multi-rotor wind turbine, characterized in that, The yaw control device includes: Processor; and, The memory stores a computer program that, when executed by a processor, performs the yaw control method as described in any one of claims 7-12.

14. A multi-rotor wind turbine generator, characterized in that, The multi-rotor wind turbine includes at least two rotors, a sensor, a yaw controller, a processor, and a memory, wherein the memory stores a computer program that, when run by the processor, executes the yaw control method as described in any one of claims 7-12.

15. A computer-readable storage medium storing a computer program, wherein, When the computer program is executed by a processor, it implements the yaw control method as described in any one of claims 7-12.

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