High-precision variable-pitch control method and system for electric propulsion aircraft

Abstract

The invention discloses a high-precision variable-pitch control method and system for an electric propulsion aircraft, and the method comprises the steps: enabling a motor to rotate clockwise after the motor is started until the motor moves to the lower limit of a variable-pitch screw rod for stalling, and recording the reading of a first rotary change position at the moment; anticlockwise rotating until the screw moves to the upper limit of the variable-pitch screw to be blocked, recording the reading of a second rotary change position at the moment, and calculating a rotary change difference value corresponding to the height of the upper part and the lower part of the screw; performing position-rotating speed-current three-ring position control on the motor; according to a target position instruction, the motor runs to an instruction position through three-loop control, interpolation processing is carried out on the target position and the height value of the screw, the actual position at the moment is calculated, and three-loop control calibration of the motor is carried out through the difference value between the actual position and the target position. According to the method, high-precision control over the position of the variable-pitch screw can be achieved under the condition that extra hardware is not added, and position errors caused by screw thread gaps of the screw are avoided.

Description

Technical Field

[0001] The present application relates to a high-precision variable pitch control technology for an electric propulsion aircraft, and more specifically to a high-precision variable pitch control method and system for an electric propulsion aircraft. Background Art

[0002] Electric propulsion aircraft have the advantages of high efficiency and high thrust-to-weight ratio, and have become an important research object for many scientific research institutes and enterprises. Especially in the fields of drones and small aircraft, electric propulsion systems are favored for their high efficiency and low noise characteristics. With the development of technology, variable pitch has become one of the key technologies to improve aircraft performance. It can change the pitch in real time according to the different load conditions of the aircraft, thereby improving flight performance. However, the accuracy of variable pitch has a great impact on flight performance. If the position of the variable pitch is not guaranteed, it will lead to serious problems such as falling. Therefore, the position accuracy control of the variable pitch is particularly important.

[0003] Existing variable pitch control methods usually rely on external position sensors to detect the position changes of the blades. Although these sensors can provide relatively accurate data, they also bring many problems. On the one hand, installing additional sensors will increase the weight and volume of the aircraft, which is an obvious disadvantage for modern aircraft that pursue lightweight and compact design. On the other hand, the environmental adaptability and reliability of the sensor are also a major challenge, especially in severe weather conditions or extreme environments, the sensor may be interfered with, resulting in inaccurate measurement results, which in turn affects the safety and stability of the aircraft.

[0004] In order to achieve high-precision variable pitch control without adding additional hardware, there is a method in the prior art that uses a rotary transformer (resolver) built into the motor for position detection. Although the resolver has high stability and strong anti-interference ability, and is suitable for applications that require high reliability, there are certain limitations to relying solely on the resolver for position control. In particular, when there is a thread gap in the screw, it will cause errors in position detection and affect the final control accuracy. This error will not only affect the performance of the aircraft, but may also bring safety hazards. Therefore, it is necessary to develop a high-precision variable pitch control method based on resolvers, which can not only avoid the high cost and large space occupied by the installation of sensors, but also eliminate the errors caused by the screw thread gap to ensure high-precision variable pitch control. Summary of the invention

[0005] In order to achieve high-precision variable pitch control without adding additional hardware, the present application provides a high-precision variable pitch control method and system for an electric propulsion aircraft.

[0006] In a first aspect, the present application provides a high-precision variable pitch control method for an electric propulsion aircraft, comprising: S1, start the motor and control the motor to rotate clockwise, monitor the rotation of the motor, and when the motor moves to the bottom of the variable pitch screw and is blocked, record the first rotary position reading at this time; S2, control the motor to rotate counterclockwise, monitor the rotation of the motor, and when the motor moves to the top of the variable pitch screw and is blocked, record the second resolver position reading at this time; S3, calculating the resolution difference corresponding to the upper and lower heights of the variable pitch screw according to the recorded first resolution position reading and the second resolution position reading; S4, perform position-speed-current three-loop servo control on the motor; S5. According to the target position command, the motor is controlled to run to the command position through the three-ring servo control; the target position and the variable pitch screw height value are interpolated in combination with the resolver difference corresponding to the upper and lower heights of the variable pitch screw, and the actual position obtained after the interpolation is obtained. The difference between the actual position and the target position is calculated, and accumulated compensation is performed with the motor running position, and three closed-loop position control is performed again to realize the motor three-ring servo control calibration.

[0007] By adopting the above scheme, the motor is started and the resolver position readings when the pitch screw is blocked below and above are recorded, the resolver difference is calculated, and the position range of the pitch screw is determined; the motor is subjected to three-loop servo control to improve the position control accuracy of the motor and eliminate the error caused by the screw thread gap; combined with the target position command, the motor runs to the command position through three-loop control, and the actual position is obtained through interpolation processing, the difference between the actual position and the target position is calculated, and cumulative compensation is performed, which further improves the accuracy of position control and realizes high-precision control of the pitch screw position of the electric propulsion aircraft.

[0008] Preferably, in step S1, the motor moves to the bottom of the variable pitch screw and stalls, and the corresponding relationship between the stall current and time is: in, is the stall current at the current moment, is the locked-rotor current coefficient, is the stall time and is the total stall time, is the rated current of the motor; analyze the waveform and peak value of the stall current to adjust the control parameters of the current loop and optimize the current response.

[0009] By adopting the above scheme, the relationship between the stall current and time is analyzed to accurately control the stall process of the motor, accurately identify the time when the stall occurs, and further adjust the control parameters of the current loop by analyzing the waveform and peak value of the stall current, optimize the current response, and improve the stability and accuracy of the motor position control.

[0010] Preferably, the formula for calculating the rotation difference corresponding to the upper and lower heights of the variable pitch screw in step S3 is: in, is the rotation difference corresponding to the upper and lower heights of the variable pitch screw, is the number of revolutions of the motor from the lower part of the screw to the upper part of the rotary transformer. is the number of resolver pole pairs; is the first resolver position reading; is the second resolver position reading.

[0011] By adopting the above scheme, the rotation difference corresponding to the upper and lower heights of the variable pitch screw is calculated, which can accurately reflect the height variation range of the screw, thereby providing an accurate data basis for the subsequent interpolation processing of the target position instruction and the actual position.

[0012] Preferably, performing position-speed-current three-loop servo control on the motor in step S4 includes: Control the position loop output, the position loop output discrete equation is: in, is the output value of the position loop at the current moment, is the position loop proportional gain, is the position feed value at the current moment, is the position feed value of the previous cycle, is the current position feedback value, is the feedforward gain, To control the cycle; Control the speed loop output. The speed loop output discrete equation is: in, is the output value of the position loop at the current moment, is the speed loop proportional gain, is the speed loop integral gain, The speed loop sets the speed. is the speed loop feedback speed, is the speed loop output of the previous cycle, To control the cycle, It is the speed loop output; it controls the current loop output and realizes the control of motor torque and speed by controlling the duty cycle of PWM.

[0013] By adopting the above scheme, the proportional gain and feedforward gain of the position loop are set to complete the precise calculation of the discrete equation of the position loop output, so that the motor can accurately follow the target position command; the proportional gain and integral gain of the speed loop are set to complete the precise calculation of the discrete equation of the speed loop output, thereby enhancing the stability and robustness of the control output; the output calculation of the current loop is completed and the PWM duty cycle is controlled to achieve effective control of the motor torque and speed.

[0014] Preferably, the current loop output control specifically includes: designing an unbiased current predictive control based on an extended state observer for the current loop; The current discrete state equation of the dq-axis extended state observer is: in, For motor dq The shaft current calculates the transition amount, Motor stator winding resistance value, To control the cycle, For motor d Shaft inductance value, For motor q Shaft inductance value, is the motor angular velocity, is the d-axis current feedback value, for q Shaft current feedback value, is the motor flux, is the observer coefficient; is the voltage output of the d-axis at time t, is the voltage output of the q-axis at time t; Without bias current prediction control, the voltage output equation is: in, Calculate the transition amount for the motor dq axis current, is the resistance value of the motor stator winding, To control the cycle, For motor d Shaft inductance value, For motor q Shaft inductance value, is the motor angular velocity, for d Shaft current setpoint, for q Shaft current setpoint, for d Axis voltage output at time t+1, for q Axis voltage output at time t+1.

[0015] By adopting the above scheme, the dq axis current is controlled by the extended state observer without bias, which can effectively deal with the distortion of the motor resistance and inductance parameters and ensure high current control accuracy under various working conditions.

[0016] Preferably, in step S5, the formula for calculating the difference between the actual position and the target position and performing cumulative compensation with the motor running position is: in, is the three closed-loop operating position of the motor, is the actual position instruction, is the position error, is the current position compensation value, is the actual position obtained by screw interpolation, is the rotation difference corresponding to the upper and lower heights of the screw, It is the resolver reading of the motor's three closed loop operation.

[0017] By adopting the above scheme, the actual position is obtained by combining the resolver reading and performing screw height interpolation, the position error between the current actual position and the expected position is accurately identified, the position error is accumulated with the motor's three-closed-loop operating position, and a new position compensation value is generated and applied to the motor's three-closed-loop control, effectively eliminating the displacement error caused by factors such as screw thread clearance, thereby improving the accuracy and stability of the motor position control.

[0018] Preferably, step S1 or step S2 further includes: When starting the motor and controlling the motor to rotate clockwise or counterclockwise, environmental data is collected synchronously and the stall judgment threshold is dynamically adjusted according to the collected environmental data. The dynamic adjustment process includes: inputting the collected environmental data into the stall threshold acquisition neural network to obtain the stall judgment threshold corresponding to the currently collected environmental data; the stall threshold acquisition neural network is generated by training the historical stall judgment threshold corresponding to the historical stall state judgment accuracy rate greater than the preset accuracy rate and the historical corresponding environmental data.

[0019] By adopting the above scheme, environmental data is collected and the stall judgment threshold is dynamically adjusted when the motor rotates clockwise or counterclockwise, so as to accurately judge the stall state of the motor under different environmental conditions and improve the accuracy of resolver difference calculation.

[0020] In a second aspect, the present application provides a high-precision variable pitch control system for an electric propulsion aircraft, comprising: The first resolver position reading recording module is used to start the motor and control the motor to rotate clockwise, monitor the rotation of the motor, and record the first resolver position reading when the motor moves below the variable pitch screw and is blocked; The second resolver position reading recording module is used to control the counterclockwise rotation of the motor and monitor the rotation of the motor. When the motor moves to the top of the variable pitch screw and is blocked, the second resolver position reading is recorded at this time. A resolver difference calculation module is used to calculate the resolver difference corresponding to the upper and lower heights of the variable pitch screw according to the recorded first resolver position reading and the second resolver position reading; The motor three-loop servo control module is used to perform position-speed-current three-loop servo control on the motor; The motor three-ring servo control calibration module is used to control the motor to run to the command position through the three-ring servo according to the target position command; combined with the resolver difference corresponding to the upper and lower heights of the variable pitch screw, the target position and the variable pitch screw height value are interpolated to obtain the actual position after interpolation, the difference between the actual position and the target position is calculated, and accumulated compensation is performed with the motor running position, and three closed-loop position control is performed again to realize the motor three-ring servo control calibration.

[0021] By adopting the above solution, high-precision control of the variable pitch screw position is achieved, the response speed and stability of the motor in complex environments are improved, the position error caused by the screw thread gap is reduced, and the overall performance and safety of the aircraft are further improved.

[0022] In a third aspect, the present application provides a computer-readable storage medium, wherein the computer-readable storage medium includes a stored computer program, wherein when the computer program is executed, the device where the computer-readable storage medium is located is controlled to execute the method as described above.

[0023] In a fourth aspect, the present application provides a computer device, comprising a memory, a processor, and a program stored and executable on the memory, wherein the program implements the steps of the above method when executed by the processor.

[0024] In summary, this application has the following beneficial effects: 1. The use of the screw propulsion motor's own resolver as a position sensor avoids the problems of increased cost, increased weight and space occupation caused by the installation of external sensors, thereby improving the overall performance and reliability of the aircraft. By performing position-speed-current three-loop servo control on the motor, and combining the resolver difference corresponding to the upper and lower heights of the variable pitch screw for interpolation processing and dynamic compensation, the error caused by the screw thread gap is eliminated, high-precision variable pitch position control is achieved, and the control performance and safety of the aircraft are improved. 2. The unbiased current predictive control method based on the extended state observer enhances the robustness of the control under the condition of motor resistance and inductance parameter distortion, and further improves the control stability and response speed; 3. Taking into account the impact of environmental changes on stalling, the environmental data is collected and the stall judgment threshold is dynamically adjusted when the motor rotates clockwise or counterclockwise, so as to accurately judge the stall status of the motor under different environmental conditions, laying the foundation for subsequent precise control. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a flow chart of a high-precision variable pitch control method for an electric propulsion aircraft described in a specific embodiment; Figure 2 It is a schematic diagram of the motor position-speed-current three-closed-loop control in the high-precision variable pitch control method for an electric propulsion aircraft described in a specific embodiment; Figure 3 It is a schematic diagram of the structure of a high-precision variable pitch control system for an electric propulsion aircraft in a specific embodiment. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0027] like Figure 1 As shown, the embodiment of the present application discloses a high-precision variable pitch control method for an electric propulsion aircraft, and the specific steps include: S1. Start the motor and control it to rotate clockwise, monitor the rotation of the motor, and when the motor moves to the bottom of the variable pitch screw and becomes blocked, record the first rotary position reading at this time.

[0028] Specifically, the clockwise rotation of the motor is monitored to obtain the state information of the motor rotation, including key data such as the motor speed, direction, torque and motor temperature. When the motor moves to the bottom of the variable pitch screw and is blocked, such as: the speed is lower than the preset speed threshold or the output current is greater than the preset current threshold, the first resolver position reading at this time is recorded as .

[0029] S2, control the motor to rotate counterclockwise, monitor the rotation of the motor, and when the motor moves to the top of the variable pitch screw and is blocked, record the second resolver position reading at this time; Specifically, similarly, the counterclockwise rotation of the motor is monitored to obtain the motor rotation status information, including key data such as the motor speed, direction, torque, and motor temperature. When the motor moves below the variable pitch screw and stalls, the second resolver position reading is recorded as .

[0030] S3. Calculate the resolution difference corresponding to the upper and lower heights of the variable pitch screw according to the recorded first resolution position reading and the second resolution position reading.

[0031] The specific formula is: in, is the rotation difference corresponding to the upper and lower heights of the variable pitch screw, is the number of revolutions of the motor from the lower part of the screw to the upper part of the rotary transformer. is the number of resolver pole pairs, which is predetermined during the design phase; is the first resolver position reading; is the second resolver position reading.

[0032] S4, perform position-speed-current three-loop servo control on the motor.

[0033] Specifically, in order to eliminate the error caused by the screw thread gap, the motor is subjected to position-speed-current three-loop servo control to ensure that the motor can accurately reach the target position.

[0034] like Figure 2 As shown, the three-loop servo control system includes a position loop, a speed loop and a current loop.

[0035] According to the deviation between the set target position and the actual feedback position, the position loop output is controlled by PID regulation (the present embodiment is designed with position loop proportional gain and feedforward gain); the position loop output discrete equation is: in, is the output value of the position loop at the current moment, is the position loop proportional gain, is the position feed value at the current moment, is the position feed value of the previous cycle, is the current position feedback value, is the feedforward gain, To control the cycle; The set value of the speed loop is formed according to the output of the position loop, and the speed loop output is controlled by PID regulation (the present embodiment is designed with a speed loop proportional gain and a speed loop integral gain). The speed loop output discrete equation is: in, is the output value of the position loop at the current moment, is the speed loop proportional gain, is the speed loop integral gain, The speed loop sets the speed. is the speed loop feedback speed, is the speed loop output of the previous cycle, To control the cycle, The speed loop output is used to set the current loop, and the PWM duty cycle is adjusted by PID to directly control the motor torque and speed.

[0036] In addition, in order to avoid the problem of reduced control performance caused by the distortion of the motor body resistance and inductance parameters, thereby improving the robustness of the three-loop control system; in this embodiment, the current loop output control also includes: designing an unbiased current prediction control based on an extended state observer for the current loop; specifically including: The extended state observer is introduced to observe and compensate the control deviation caused by the change of motor parameters in real time. For example, the current of the dq axis is observed, and the current discrete state equation of the dq axis extended state observer is: in, For motor dq The shaft current calculates the transition amount, Motor stator winding resistance value, To control the cycle, For motor d Shaft inductance value, For motor q Shaft inductance value, is the motor angular velocity, is the d-axis current feedback value, for q Shaft current feedback value, is the motor flux, is the observer coefficient; is the voltage output of the d-axis at time t, is the voltage output of the q-axis at time t; The unbiased current prediction control is introduced to predict the current value at the next moment, and the optimal control voltage is calculated through the optimization algorithm, so that the actual current can quickly track the given value; the current and voltage output equations are: in, Calculate the transition amount for the motor dq axis current, is the resistance value of the motor stator winding, To control the cycle, For motor d Shaft inductance value, For motor q Shaft inductance value, is the motor angular velocity, for d Shaft current setpoint, for q Shaft current setpoint, for d Axis voltage output at time t+1, for q Axis voltage output at time t+1.

[0037] S5. Implement the motor three-ring servo control calibration.

[0038] Specifically, according to the target position command, the motor is controlled by the three-loop servo to run to the command position; wherein the three closed-loop running positions of the motor are , the actual position command is , combined with the rotation difference corresponding to the upper and lower heights of the variable pitch screw, the target position and the variable pitch screw height value are interpolated to obtain the actual position obtained after the difference processing , calculate the actual position With instruction position The difference between the motor's three closed-loop operating positions Add up to get , and three-loop closed-loop position control is performed again to realize the motor three-loop servo control calibration.

[0039] Among them, the cumulative compensation is The formulas include: The formula for cumulative compensation of the running command position is: in, is the three closed-loop operating position of the motor, is the actual position instruction, is the position error, is the current position compensation value, is the actual position obtained by screw interpolation, is the rotation difference corresponding to the upper and lower heights of the screw, It is the initial rotation reading below the pitch screw; It is the resolver reading of the motor's three closed loop operation.

[0040] In a specific embodiment, in order to achieve control stability and performance, the control parameters of the current loop can be adjusted to optimize the current response. The method includes: In step S1, the motor moves to the bottom of the variable pitch screw and stalls. The relationship between the stall current and time is: in, is the stall current at the current moment, is the locked-rotor current coefficient, is the stall time and is the total stall time, is the rated current of the motor; Analyze the waveform and peak value of the stall current to adjust the control parameters of the current loop and optimize the current response. Specifically, it includes: identifying the waveform characteristics of the collected stall current waveform, marking the peak value of each stall current, and analyzing its change trend. Based on the results of waveform analysis and peak detection, adjust the control parameters of the current loop such as proportional gain, integral time and differential time, select the optimization algorithm, and obtain the parameter combination with the fastest current response and the smallest overshoot.

[0041] In a specific embodiment, different environmental conditions are taken into consideration to accurately capture the stall state of the motor and ensure more accurate calculation of the resolver difference. In the method, step S1 or step S2 further includes: When the motor is started and controlled to rotate clockwise or counterclockwise, environmental data is collected synchronously; the environmental data includes temperature, humidity, vibration, etc.

[0042] The stall threshold is adjusted dynamically based on the collected environmental data. The dynamic adjustment process includes: The collected environmental data is input into the jam threshold acquisition neural network to obtain the jam judgment threshold corresponding to the currently collected environmental data; the jam threshold acquisition neural network inputs the collected environmental data and outputs the jam judgment threshold, including: a preset speed threshold and a preset current threshold, which is specifically generated by training the historical jam judgment threshold corresponding to the historical jam state judgment accuracy rate greater than the preset accuracy rate and the historical environmental data at the corresponding time; wherein the historical jam state judgment accuracy rate is determined based on the actual jam state (jam occurs, no jam occurs) and the judged jam state.

[0043] like Figure 3 As shown, this embodiment provides a high-precision variable pitch control system for an electric propulsion aircraft, specifically comprising: The first resolver position reading recording module 101 is used to start the motor and control the motor to rotate clockwise, monitor the rotation of the motor, and record the first resolver position reading when the motor moves below the variable pitch screw and is blocked; The second resolver position reading recording module 102 is used to control the motor to rotate counterclockwise, monitor the rotation of the motor, and record the second resolver position reading when the motor moves above the variable pitch screw and is blocked; The resolver difference calculation module 103 is used to calculate the resolver difference corresponding to the upper and lower heights of the variable pitch screw according to the recorded first resolver position reading and the second resolver position reading; The motor three-loop servo control module 104 is used to perform position-speed-current three-loop servo control on the motor; The motor three-ring servo control calibration module 105 is used to control the motor to run to the command position through the three-ring servo according to the target position command; in combination with the rotary transformer difference corresponding to the upper and lower heights of the variable pitch screw, the target position and the variable pitch screw height value are interpolated to obtain the actual position obtained after the interpolation process, the difference between the actual position and the target position is calculated, and accumulated compensation is performed with the running position, and three closed-loop position control is performed again to realize the motor three-ring servo control calibration.

[0044] In a specific embodiment, the first resolver position reading recording module 101 in the system is also used to start the motor, control the motor to rotate clockwise, synchronously collect environmental data and dynamically adjust the stall judgment threshold according to the collected environmental data, and the dynamic adjustment process includes: inputting the collected environmental data into the stall threshold acquisition neural network to obtain the stall judgment threshold corresponding to the currently collected environmental data; the stall threshold acquisition neural network is generated by training the historical stall judgment threshold corresponding to the historical stall state judgment accuracy rate greater than the preset accuracy rate and the historical corresponding moment environmental data.

[0045] In a specific embodiment, the first resolver position reading recording module 102 in the system is also used to start the motor, control the motor to rotate counterclockwise, synchronously collect environmental data and dynamically adjust the stall judgment threshold according to the collected environmental data, and the dynamic adjustment process includes: inputting the collected environmental data into the stall threshold acquisition neural network to obtain the stall judgment threshold corresponding to the currently collected environmental data; the stall threshold acquisition neural network is generated by training the historical stall judgment threshold corresponding to the historical stall state judgment accuracy rate greater than the preset accuracy rate and the historical corresponding moment environmental data.

[0046] The embodiment of the present application also discloses a computer-readable storage medium.

[0047] Specifically, the computer-readable storage medium stores a computer program that can be loaded by a processor and executed such as the above-mentioned high-precision variable pitch control method for an electric propulsion aircraft. The computer-readable storage medium includes, for example: a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and other media that can store program codes.

[0048] The embodiment of the present application also discloses a computer device.

[0049] Specifically, the computer device includes a memory and a processor, and the memory stores a computer program that can be loaded by the processor and execute the above-mentioned high-precision variable pitch control method for the electric propulsion aircraft.

[0050] The above are all preferred embodiments of the present application, and are not intended to limit the protection scope of the present application. Any feature disclosed in this specification (including the abstract and drawings), unless otherwise stated, can be replaced by other equivalent or alternative features with similar purposes. That is, unless otherwise stated, each feature is only an example of a series of equivalent or similar features.

Claims

1. A high-precision variable pitch control method for an electric propulsion aircraft, characterized in that: include: S1, start the motor and control the motor to rotate clockwise, monitor the rotation of the motor, and when the motor moves to the bottom of the variable pitch screw and is blocked, record the first rotary position reading at this time; S2, control the motor to rotate counterclockwise, monitor the rotation of the motor, and when the motor moves to the top of the variable pitch screw and is blocked, record the second resolver position reading at this time; S3, calculating the resolution difference corresponding to the upper and lower heights of the variable pitch screw according to the recorded first resolution position reading and the second resolution position reading; S4, perform position-speed-current three-loop servo control on the motor; S5. According to the target position command, the motor is controlled to run to the command position through the three-ring servo control; the target position and the variable pitch screw height value are interpolated in combination with the resolver difference corresponding to the upper and lower heights of the variable pitch screw, and the actual position obtained after the interpolation is obtained. The difference between the actual position and the target position is calculated, and accumulated compensation is performed with the motor running position, and three closed-loop position control is performed again to realize the motor three-ring servo control calibration.

2. The high-precision variable pitch control method for an electric propulsion aircraft according to claim 1, characterized in that: In step S1, the motor moves to the bottom of the variable pitch screw and stalls. The corresponding relationship between the stall current and time is: in, is the stall current at the current moment, is the locked-rotor current coefficient, is the stall time and is the total stall time, is the rated current of the motor; analyze the waveform and peak value of the stall current to adjust the control parameters of the current loop and optimize the current response.

3. The high-precision variable pitch control method for an electric propulsion aircraft according to claim 1, characterized in that: The formula for calculating the rotation difference corresponding to the upper and lower heights of the variable pitch screw in step S3 is: in, is the rotation difference corresponding to the upper and lower heights of the variable pitch screw, is the number of revolutions of the motor from the lower part of the screw to the upper part of the rotary transformer. is the number of resolver pole pairs; is the first resolver position reading; is the second resolver position reading.

4. The high-precision variable pitch control method for an electric propulsion aircraft according to claim 1, characterized in that: The position-speed-current three-loop servo control of the motor in step S4 includes: Control the position loop output, the position loop output discrete equation is: in, is the output value of the position loop at the current moment, is the position loop proportional gain, is the position feed value at the current moment, is the position feed value of the previous cycle, is the current position feedback value, is the feedforward gain, To control the cycle; Control the speed loop output. The speed loop output discrete equation is: in, is the output value of the position loop at the current moment, is the speed loop proportional gain, is the speed loop integral gain, The speed loop sets the speed. is the speed loop feedback speed, is the speed loop output of the previous cycle, To control the cycle, It is the speed loop output; it controls the current loop output and realizes the control of motor torque and speed by controlling the duty cycle of PWM.

5. The high-precision variable pitch control method for an electric propulsion aircraft according to claim 4, characterized in that: The current loop output control specifically includes: designing an unbiased current predictive control based on an extended state observer for the current loop; The current discrete state equation of the dq-axis extended state observer is: in, For motor dq The shaft current calculates the transition amount, Motor stator winding resistance value, To control the cycle, For motor d Shaft inductance value, For motor q Shaft inductance value, is the motor angular velocity, is the d-axis current feedback value, for q Shaft current feedback value, is the motor flux, is the observer coefficient; is the voltage output of the d-axis at time t, is the voltage output of the q-axis at time t; Without bias current prediction control, the voltage output equation is: in, Calculate the transition amount for the motor dq axis current, is the resistance value of the motor stator winding, To control the cycle, For motor d Shaft inductance value, For motor q Shaft inductance value, is the motor angular velocity, for d Shaft current setpoint, for q Shaft current setpoint, for d Axis voltage output at time t+1, for q Axis voltage output at time t+1.

6. The high-precision variable pitch control method for an electric propulsion aircraft according to claim 4, characterized in that: In step S5, the difference between the actual position and the target position is calculated and the formula for cumulative compensation with the motor running position is: in, is the three closed-loop operating position of the motor, is the actual position instruction, is the position error, is the current position compensation value, is the actual position obtained by screw interpolation, is the rotation difference corresponding to the upper and lower heights of the screw, It is the resolver reading of the motor's three closed loop operation.

7. The high-precision variable pitch control method for an electric propulsion aircraft according to claim 1, characterized in that: Step S1 or step S2 also includes: When starting the motor and controlling the motor to rotate clockwise or counterclockwise, environmental data is collected synchronously and the stall judgment threshold is dynamically adjusted according to the collected environmental data. The dynamic adjustment process includes: inputting the collected environmental data into the stall threshold acquisition neural network to obtain the stall judgment threshold corresponding to the currently collected environmental data; the stall threshold acquisition neural network is generated by training the historical stall judgment threshold corresponding to the historical stall state judgment accuracy rate greater than the preset accuracy rate and the historical corresponding environmental data.

8. A high-precision variable pitch control system for an electric propulsion aircraft, characterized in that: include: The first resolver position reading recording module is used to start the motor and control the motor to rotate clockwise, monitor the rotation of the motor, and record the first resolver position reading when the motor moves below the variable pitch screw and is blocked; The second resolver position reading recording module is used to control the counterclockwise rotation of the motor and monitor the rotation of the motor. When the motor moves to the top of the variable pitch screw and is blocked, the second resolver position reading is recorded at this time. A resolver difference calculation module is used to calculate the resolver difference corresponding to the upper and lower heights of the variable pitch screw according to the recorded first resolver position reading and the second resolver position reading; The motor three-loop servo control module is used to perform position-speed-current three-loop servo control on the motor; The motor three-ring servo control calibration module is used to control the motor to run to the command position through the three-ring servo according to the target position command; combined with the resolver difference corresponding to the upper and lower heights of the variable pitch screw, the target position and the variable pitch screw height value are interpolated to obtain the actual position after the difference processing, the difference between the actual position and the target position is calculated, and accumulated compensation is performed with the motor running position, and three closed-loop position control is performed again to realize the motor three-ring servo control calibration.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium includes a stored computer program, wherein when the computer program is executed, the device where the computer-readable storage medium is located is controlled to execute the method according to any one of claims 1 to 7.

10. A computer device, characterized in that: The computer device comprises a memory, a processor and a program stored and executable on the memory, and the program implements the steps of the method according to any one of claims 1 to 7 when executed by the processor.

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