Power optimization control method for variable pitch propeller

Abstract

The application relates to the technical field of engine performance calculation technology, in particular to a power optimization control method of a variable-pitch propeller. The power optimization control method of the variable-pitch propeller can obtain a power optimization working relationship of the propeller. Based on the power optimization working relationship of the propeller, a power coefficient can be determined on the preset power optimization working relationship of the propeller according to the working condition and the thrust demand, and the minimum power is obtained. That is, under the premise of the same flight working condition and the same thrust demand, there is only one set of speed or pitch angle combination of the variable-pitch propeller propulsion system, so that the power consumed by the propulsion system is minimum, and the variable-pitch propeller propulsion system is in the optimal propulsion efficiency at any time, thereby achieving the technical effect of aviation low carbon and environmental protection.

Description

Technical Field

[0001] This application relates to the field of engine performance calculation technology, and in particular to a power optimization control method for a variable pitch propeller. Background Technology

[0002] The propeller generates thrust to provide forward propulsion for the aircraft by connecting a turbine gas engine and an electric motor. The relationship between the power required by the propeller, the thrust provided, the rotational speed, and the pitch angle constitutes the control law of the propeller propulsion system.

[0003] Typically, the control logic of a variable-pitch propeller is constant-speed propeller control. The propeller's pitch angle is adjusted by its built-in constant-speed controller to keep the propeller running at a predetermined speed. This predetermined speed can be adjusted manually by the pilot or automatically by the flight control system.

[0004] The role of constant speed control in related technologies is more to expand the operating range of the propeller, enabling it to absorb more power and generate greater thrust over a wider airspeed range. However, constant speed control cannot guarantee that the propeller will operate at its highest propulsion efficiency under specific flight conditions. Summary of the Invention

[0005] This application provides a power optimization control method for a variable-pitch propeller, which can effectively solve the above-mentioned or other potential technical problems.

[0006] The first aspect of this application is to provide a power optimization control method for a variable-pitch propeller, comprising:

[0007] Adjust the general characteristic diagram of the variable pitch propeller to obtain a constant thrust characteristic diagram;

[0008] In the constant thrust characteristic diagram, m constant thrust lines are selected, and the functional relationship between the m constant thrust lines is obtained by fitting. At this time, the functional relationship is that each advance ratio has a corresponding power coefficient, where m is a positive integer greater than or equal to 2.

[0009] Based on the functional relationship of the m equal thrust lines, obtain the maximum value array on the functional relationship of each equal thrust line. The maximum value array is the power coefficient and advance ratio corresponding to the maximum thrust efficiency.

[0010] The characteristic map of the constant thrust line, which is formed by the array of the maximum values ​​of each of the m constant thrust lines, is interpolated and fitted with the preset propeller characteristic map to obtain the preset propeller power optimization working relationship.

[0011] Based on the operating conditions and thrust requirements, the power coefficient is determined on the preset power optimization working relationship of the propeller, thereby obtaining the minimum power.

[0012] In an optional embodiment according to the first aspect, the general characteristic diagram of the variable-pitch propeller can be obtained from propeller aerodynamic theory as follows:

[0013]

[0014]

[0015]

[0016] Among them, F p For propeller thrust, C T Where ρ is the propeller thrust coefficient, ρ is the air density, and n is the propeller thrust coefficient. s Where is the propeller speed, D is the propeller disk diameter, λ is the advance ratio, v0 is the incoming flow velocity, and P is the propeller rotation speed. P The input power of the propeller, C P This represents the power coefficient of the propeller.

[0017] In an alternative embodiment according to the first aspect, the following is derived according to formulas (1), (2), and (3):

[0018]

[0019] Where, η net This refers to the propulsion efficiency of the propeller.

[0020] In an optional embodiment according to the first aspect, obtaining the constant thrust characteristic map specifically includes:

[0021] Divide both sides of the above formula (2) by λ 2 This yields a dimensionless expression independent of rotational speed:

[0022]

[0023] in, To correct the thrust coefficient.

[0024] In an optional embodiment according to the first aspect, the preset propeller characteristic diagram needs to be selected as required, and the selected preset propeller characteristic diagram includes an equal propulsion efficiency line.

[0025] The characteristic diagram of the constant thrust line, which is formed by the array of the maximum values ​​of each of the m constant thrust lines, is interpolated and fitted with the preset propeller characteristic diagram to obtain the preset propeller power optimization working relationship.

[0026] In an optional embodiment according to the first aspect, the preset propeller characteristic diagram is selected, wherein the parameters of the preset propeller characteristic diagram are: the number of propeller blades is 4, the propeller utility factor is 100, and the propeller overall lift coefficient is 0.5.

[0027] In an alternative embodiment according to the first aspect,

[0028]

[0029]

[0030] Based on the selected preset propeller characteristic diagram, formula (4) and formula (5), the propeller parameter power coefficient C can be determined. P、 approach ratio λ, corrected thrust coefficient propeller propulsion efficiency η net and propeller thrust coefficient C T The correspondence between them; and based on the corresponding relationship between the above propeller parameters, a corrected thrust coefficient corresponding to the selected preset propeller characteristic diagram is plotted. The contour map.

[0031] In an optional embodiment according to the first aspect, m isothropy lines are selected in the isothropy characteristic diagram, where m is 10.

[0032] By mapping each maximum value array in the functional relationship of the 10 obtained thrust contour lines to the characteristic diagram of the propeller to be used, 10 sets of maximum value arrays are obtained on the 10 thrust contour lines, as shown in the table below:

[0033]

[0034] In an optional embodiment according to the first aspect, based on 10 sets of maximum values ​​on 10 obtained thrust contour lines, a preset propeller power optimization working relationship can be obtained by interpolating and fitting the 10 sets of efficiency optimum points:

[0035] C P =0.3479λ 3 -0.5337λ 2 +0.1832λ+0.125 (6)

[0036] The power optimization control method for variable pitch propellers proposed in this patent application can obtain the power optimization working relationship of the propeller. Based on the power optimization working relationship of the propeller, it is convenient to determine the power coefficient on the preset power optimization working relationship of the propeller according to the operating conditions and thrust requirements, thereby obtaining the minimum power. That is, under the same flight conditions and the same thrust requirements, there is a unique combination of rotational speed or pitch angle in the variable pitch propulsion system, which minimizes the power consumed by the propulsion system and keeps the variable pitch propulsion system at the optimal propulsion efficiency at all times, thus achieving the technical effect of low carbon and environmental protection in aviation.

[0037] Additional advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0038] The above and other objects, features, and advantages of embodiments of this application will become more readily understood from the following detailed description with reference to the accompanying drawings. In the drawings, several embodiments of this application will be described by way of example and non-limitation, wherein:

[0039] Figure 1 A flowchart illustrating the power optimization control method for a variable-pitch propeller provided in this application embodiment;

[0040] Figure 2 A schematic diagram of the power optimization working line obtained by fitting in the power optimization control method for variable pitch propellers provided in the embodiments of this application;

[0041] Figure 3a A schematic diagram of the flight altitude versus time curve of a propeller in flight conditions provided in this application embodiment;

[0042] Figure 3b A schematic diagram of the flight speed of a propeller under flight conditions as provided in the embodiments of this application;

[0043] Figure 3c A schematic diagram of the thrust demand of a propeller under flight conditions versus time, provided in an embodiment of this application;

[0044] Figure 4 A schematic diagram comparing the propeller efficiency characteristics under two control laws;

[0045] Figure 5 This diagram illustrates the power demand of a propeller propulsion system under two different control laws. Detailed Implementation

[0046] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0047] It should be understood that the following embodiments do not limit the execution order of the steps in the method protected by this application. The steps of the method of this application can be executed in any possible order and in a cyclic manner without contradicting each other.

[0048] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0049] The propeller, by connecting a turbojet engine and an electric motor, generates thrust to provide forward propulsion for the aircraft. The relationship between the propeller's power requirements, thrust provided, rotational speed, and pitch angle constitutes the control logic of the propeller propulsion system. Typically, variable-pitch propellers use constant-speed propeller control, where the propeller's built-in constant-speed controller adjusts the pitch angle to maintain a predetermined rotational speed. This speed can be manually adjusted by the pilot or automatically by the flight control system. Constant-speed control in related technologies primarily aims to extend the propeller's operating range, enabling it to absorb more power and generate greater thrust over a wider airspeed range. However, constant-speed control cannot guarantee that the propeller will operate at its highest propulsive efficiency under specific flight conditions.

[0050] In view of this, the power optimization control method for a variable-pitch propeller provided in this application includes: adjusting the general characteristic diagram of the variable-pitch propeller to obtain a constant thrust line characteristic diagram; selecting m constant thrust lines in the constant thrust line characteristic diagram, and obtaining the functional relationship of the m constant thrust lines by fitting, wherein each advance ratio has a corresponding power coefficient, and m is a positive integer greater than or equal to 2; obtaining the maximum value array on the functional relationship of each constant thrust line according to the functional relationship of the m constant thrust lines, wherein the maximum value array is the power coefficient and advance ratio corresponding to the maximum thrust efficiency; interpolating and fitting the constant thrust line characteristic diagram formed by the maximum value array of each of the obtained functional relationships of the m constant thrust lines with a preset propeller characteristic diagram to obtain a preset propeller power optimization working relationship; determining the power coefficient on the preset propeller power optimization working relationship according to the operating conditions and thrust requirements, thereby obtaining the minimum power.

[0051] The power optimization control method for variable pitch propellers proposed in this patent application can obtain the power optimization working relationship of the propeller. Based on the power optimization working relationship of the propeller, it is convenient to determine the power coefficient on the preset power optimization working relationship of the propeller according to the operating conditions and thrust requirements, thereby obtaining the minimum power. That is, under the same flight conditions and the same thrust requirements, there is a unique combination of rotational speed or pitch angle in the variable pitch propulsion system, which minimizes the power consumed by the propulsion system and keeps the variable pitch propulsion system at the optimal propulsion efficiency at all times, thus achieving the technical effect of low carbon and environmental protection in aviation.

[0052] Please refer to Figure 1 and Figure 2 The power optimization control method for a variable-pitch propeller provided in this application includes:

[0053] Adjust the general characteristic diagram of the variable pitch propeller to obtain a constant thrust characteristic diagram;

[0054] In the constant thrust characteristic diagram, m constant thrust lines are selected, and the functional relationship between the m constant thrust lines is obtained by fitting. At this time, the functional relationship is that each advance ratio has a corresponding power coefficient, where m is a positive integer greater than or equal to 2.

[0055] Based on the functional relationship of the m equal thrust lines, obtain the maximum value array on the functional relationship of each equal thrust line. The maximum value array is the power coefficient and advance ratio corresponding to the maximum thrust efficiency.

[0056] The characteristic map of the constant thrust line, which is formed by the array of the maximum values ​​of each of the m constant thrust lines, is interpolated and fitted with the preset propeller characteristic map to obtain the preset propeller power optimization working relationship.

[0057] Based on the operating conditions and thrust requirements, the power coefficient is determined on the preset power optimization working relationship of the propeller, thereby obtaining the minimum power.

[0058] The power optimization control method for variable pitch propellers proposed in this patent application can obtain the power optimization working relationship of the propeller. Based on the power optimization working relationship of the propeller, it is convenient to determine the power coefficient on the preset power optimization working relationship of the propeller according to the operating conditions and thrust requirements, thereby obtaining the minimum power. That is, under the same flight conditions and the same thrust requirements, there is a unique combination of rotational speed or pitch angle in the variable pitch propulsion system, which minimizes the power consumed by the propulsion system and keeps the variable pitch propulsion system at the optimal propulsion efficiency at all times, thus achieving the technical effect of low carbon and environmental protection in aviation.

[0059] In an optional exemplary embodiment, the general characteristic diagram of the variable-pitch propeller can be obtained according to propeller aerodynamic theory:

[0060]

[0061]

[0062]

[0063] Among them, F p For propeller thrust, C T Where ρ is the propeller thrust coefficient, ρ is the air density, and n is the propeller thrust coefficient. s Where is the propeller speed, D is the propeller disk diameter, λ is the advance ratio, v0 is the incoming flow velocity, and P is the propeller rotation speed. P The input power of the propeller, C P This represents the power coefficient of the propeller.

[0064] It should be noted that, specifically, in this embodiment, the general characteristic diagram of the variable pitch propeller can be obtained based on propeller aerodynamic theory.

[0065] In an optional exemplary embodiment, the following is derived according to formulas (1), (2), and (3):

[0066]

[0067] Where, η net This refers to the propulsion efficiency of the propeller.

[0068] It should be noted that, specifically, in this embodiment, the propeller propulsion efficiency formula can be obtained by adjusting the three formulas (1), (2), and (3) above. Specifically, the adjustment method can be to divide formula (2) by formula (3) and combine it with formula (1) to obtain:

[0069]

[0070] Since the maximum value array is the power coefficient and advance ratio corresponding to the maximum thrust efficiency, after obtaining formula (4), it is convenient to obtain the maximum value array on the functional relationship of each constant thrust line based on formula (4).

[0071] In an optional exemplary embodiment, obtaining the constant thrust characteristic map specifically includes:

[0072] Divide both sides of the above formula (2) by λ 2 This yields a dimensionless expression independent of rotational speed:

[0073]

[0074] in, To correct the thrust coefficient.

[0075] It should be noted that, specifically, in this embodiment, both sides of the above formula (2) are divided by λ. 2 This yields a dimensionless expression independent of rotational speed:

[0076]

[0077] Formulas (5) and (4) facilitate the acquisition of the working relationship for propeller power optimization.

[0078] In an optional exemplary embodiment, the preset propeller characteristic diagram needs to be selected according to requirements, and the selected preset propeller characteristic diagram includes an equal propulsion efficiency line;

[0079] The characteristic diagram of the constant thrust line, which is formed by the array of the maximum values ​​of each of the m constant thrust lines, is interpolated and fitted with the preset propeller characteristic diagram to obtain the preset propeller power optimization working relationship.

[0080] It should be noted that, specifically, in this embodiment, the preset propeller characteristic diagram needs to be selected according to requirements. The selected preset propeller characteristic diagram includes constant thrust efficiency lines. The propeller characteristic diagram is an existing one that can be obtained by consulting a tool manual. Based on the user's preset parameters, the preset propeller characteristic diagram is selected. In order to facilitate the interpolation fitting between the selected preset propeller characteristic diagram and the constant thrust line characteristic diagram composed of the maximum value array of each of the m constant thrust lines in the functional relationship, the selected preset propeller characteristic diagram needs to include constant thrust efficiency lines.

[0081] In an optional exemplary embodiment, the preset propeller characteristic diagram is selected, wherein the parameters of the preset propeller characteristic diagram are: the number of propeller blades is 4, the propeller utility factor is 100, and the propeller overall lift coefficient is 0.5.

[0082] It should be noted that, specifically, in this embodiment, the preset propeller characteristic diagram is selected, wherein the parameters of the preset propeller characteristic diagram are: the number of propeller blades is 4, the propeller utility factor is 100, and the propeller overall lift coefficient is 0.5. It is understood that the parameters of the selected preset propeller characteristic diagram are not limited here; in other specific embodiments, they can be adaptively selected according to the user's specific needs.

[0083] In an optional exemplary embodiment,

[0084]

[0085]

[0086] Based on the selected preset propeller characteristic diagram, formula (4) and formula (5), the propeller parameter power coefficient C can be determined. P approach ratio λ, corrected thrust coefficient propeller propulsion efficiency η net and propeller thrust coefficient C T The correspondence between them; and based on the corresponding relationship between the above propeller parameters, a corrected thrust coefficient corresponding to the selected preset propeller characteristic diagram is plotted. The contour map.

[0087] It should be noted that, specifically, in this embodiment, the propeller's parameter power coefficient C can be determined based on the selected preset propeller characteristic diagram, formula (4), and formula (5). P approach ratio λ, corrected thrust coefficient propeller propulsion efficiency η net and propeller thrust coefficient C TThe correspondence between them; and based on the corresponding relationship between the above propeller parameters, a corrected thrust coefficient corresponding to the selected preset propeller characteristic diagram is plotted. The contour map facilitates the application of modified thrust coefficients. The contour map is used to obtain the working relationship for power optimization.

[0088] In an optional exemplary embodiment, m isothrust lines are selected in the isothrust characteristic map, where m is 10. Each maximum value array in the functional relationship of the 10 isothrust lines is mapped to the propeller characteristic map to be used, resulting in 10 sets of maximum value arrays on the 10 thrust isothrust lines, as shown in the table below:

[0089]

[0090] It should be noted that, specifically, in this embodiment, m is 10. The maximum value array of each of the 10 obtained thrust contour lines is corresponding to the propeller characteristic diagram to be used, and 10 sets of maximum value arrays are obtained on the 10 thrust contour lines. It can be understood that the specific value of m is not limited here. In other specific embodiments, m can be any positive integer greater than or equal to 2 according to the user's specific needs.

[0091] In an optional exemplary embodiment, based on the 10 sets of maximum values ​​on the 10 obtained thrust contour lines, a preset power optimization working relationship for the propeller can be obtained by interpolating and fitting the 10 sets of efficiency optimum points:

[0092] C P =0.3479λ 3 -0.5337λ 2 +0.1832λ+0.125 (6)

[0093] It should be noted that, specifically, in this embodiment, based on the 10 sets of maximum value arrays on the 10 thrust contour lines, the preset propeller power optimization working relationship can be obtained by interpolating and fitting the 10 sets of efficiency optimum points. It is understood that this formula is not unique and fixed, and it can be varied according to the selected propeller characteristic diagram and the specific value of m. That is, the above-mentioned propeller power optimization working relationship formula (6) is obtained based on the selected parameters. In other specific embodiments, the user can adaptively select the parameters required by the user according to the variable pitch propeller power optimization control method provided in this application embodiment, and then determine the propeller power optimization working relationship formula corresponding to the selected parameters. Based on the propeller power optimization working relationship formula, the power coefficient is determined on the preset propeller power optimization working relationship according to the operating conditions and thrust requirements, and then the minimum power is obtained.

[0094] To further illustrate the technical effectiveness of the power optimization control method for variable-pitch propellers provided in the embodiments of this application, this application verifies the above-mentioned control method as follows:

[0095] Please refer to Figures 3a-3c The analysis is based on the characteristics of a conventional variable-pitch propeller, including flight conditions and thrust requirements. Figures 3a-3c As shown, under the same flight profile and thrust requirements, the propeller system is compared and analyzed using the power optimization control method (also known as the optimal power control law, which is described in the figure) and the constant speed control law of the variable pitch propeller provided in the embodiments of this application.

[0096] Please refer to Figure 4 If the power optimization control method of the variable pitch propeller proposed in the embodiments of this application is adopted throughout the flight mission, the propeller efficiency is 88.1% and 77.4% at the highest and lowest during the climb phase, and 91.2% and 90.8% at the highest and lowest during the cruise phase. The propulsion system power consumption is 376kW and 290kW at the highest and lowest during the climb phase, and 119kW and 99kW at the highest and lowest during the cruise phase.

[0097] If the traditional constant speed control law (referred to as the constant speed method) is adopted throughout the flight mission, the propeller efficiency is 83.8% and 68.9% at the highest and lowest during the climb phase, and 89.1% and 87.4% at the highest and lowest during the cruise phase; the propulsion system power consumption is 422kW and 305kW at the highest and lowest during the climb phase, and 122kW and 103kW at the highest and lowest during the cruise phase.

[0098] Please refer to Figure 5Comparing the two calculation results, the power optimization control method for the variable-pitch propeller proposed in the embodiments of this application was adopted, which improved the maximum climb efficiency by 5.13% and the minimum climb efficiency by 12.3%; and improved the maximum cruise efficiency by 2.3% and the minimum cruise efficiency by 3.9%. Figure 5 It can be seen that the power consumption of the optimization method is lower than that of the constant speed method at any time. The above results prove that, compared with the constant speed control law, the optimal power control law can effectively improve the efficiency of the propeller propulsion system and reduce energy consumption.

[0099] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

[0100] It should also be noted that the various specific technical features described in the above embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, this application will not describe the various possible combinations separately.

Claims

1. A power optimization control method for a variable-pitch propeller, characterized in that, The power optimization control method for the variable-pitch propeller includes: Adjust the general characteristic diagram of the variable pitch propeller to obtain a constant thrust characteristic diagram; In the constant thrust characteristic diagram, m constant thrust lines are selected, and the functional relationship of the m constant thrust lines is obtained by fitting. At this time, the functional relationship is that each advance ratio has a corresponding power coefficient, where m is a positive integer greater than or equal to 2. Based on the functional relationship of the m equal thrust lines, obtain the maximum value array on the functional relationship of each equal thrust line. The maximum value array is the power coefficient and advance ratio corresponding to the maximum thrust efficiency. The characteristic map of the constant thrust line, which is formed by the array of the maximum values ​​of each of the m constant thrust lines, is interpolated and fitted with the preset propeller characteristic map to obtain the preset propeller power optimization working relationship. Based on the operating conditions and thrust requirements, the power coefficient is determined on the preset power optimization working relationship of the propeller, thereby obtaining the minimum power.

2. The power optimization control method for a variable-pitch propeller according to claim 1, characterized in that, The general characteristic diagram of the variable-pitch propeller can be obtained from propeller aerodynamic theory: ， in, F p For propeller thrust, C T This is the propeller thrust coefficient. air density, propeller speed, D Where is the propeller disk diameter, and λ is the advance ratio. Incoming flow velocity, P P The input power of the propeller, C P This represents the power coefficient of the propeller.

3. The power optimization control method for a variable-pitch propeller according to claim 2, characterized in that, Based on formulas (1), (2), and (3), we can derive: ，（4） in, η net This refers to the propulsion efficiency of the propeller.

4. The power optimization control method for a variable-pitch propeller according to claim 3, characterized in that, Obtaining the isothrust characteristic diagram specifically includes: Divide both sides of the above formula (2) by This yields a dimensionless expression independent of rotational speed: （5） in, To correct the thrust coefficient.

5. The power optimization control method for a variable-pitch propeller according to claim 4, characterized in that, The preset propeller characteristic diagram needs to be selected according to the requirements. The selected preset propeller characteristic diagram includes the constant propulsion efficiency line. The characteristic diagram of the constant thrust line, which is formed by the array of the maximum values ​​of each of the m constant thrust lines, is interpolated and fitted with the preset propeller characteristic diagram to obtain the preset propeller power optimization working relationship.

6. The power optimization control method for a variable-pitch propeller according to claim 5, characterized in that, Select the preset propeller characteristic diagram, wherein the parameters of the preset propeller characteristic diagram are: the number of propeller blades is 4, the propeller utility factor is 100, and the propeller overall lift coefficient is 0.

5.

7. The power optimization control method for a variable-pitch propeller according to claim 6, characterized in that, Based on the selected preset propeller characteristic diagram, formula (4) and formula (5), the propeller parameter power coefficient C can be determined. P、 approach ratio λ, corrected thrust coefficient propeller propulsion efficiency η net and propeller thrust coefficient C T The correspondence between them; and based on the corresponding relationship between the above propeller parameters, a corrected thrust coefficient corresponding to the selected preset propeller characteristic diagram is plotted. The contour map.

8. The power optimization control method for a variable-pitch propeller according to claim 7, characterized in that, The constant thrust characteristic diagram selects m constant thrust lines, where m is 10. The maximum value array in each of the 10 obtained thrust contour lines is mapped to the propeller characteristic diagram, resulting in 10 sets of maximum value arrays on the 10 thrust contour lines, as shown in the table below: 。 9. The power optimization control method for a variable-pitch propeller according to claim 8, characterized in that, Based on the 10 sets of maximum values ​​obtained from the 10 thrust contour lines, the preset power optimization working relationship of the propeller can be obtained by interpolating and fitting the 10 sets of efficiency optimum points: （6）。

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