Electric angle calibration method for three-self-inertia-unit motor

Abstract

A three-self-inertial-unit motor electric angle calibration method comprises the steps that an outer frame is rotated to the position close to a limiting block, a given motor 0-degree vector d-axis control quantity is controlled, and an outer frame motor is pulled to a motor 0-phase point; sequentially giving a 60-degree vector d-axis control quantity, a 120-degree vector d-axis control quantity and a 180-degree vector d-axis control quantity every two seconds; in the given process, the outer frame motor can continuously rotate in one direction, whether the angle of the motor is blocked or not is judged, and if yes, it is indicated that the outer frame moves to the limiting block; at the moment, a vector value is given reversely, 60 degrees are reduced every time by taking a phase value before giving as a reference, and when the phase angle is reduced to 0, a mechanical angle value of the outer frame is recorded; and storing the recorded mechanical angle value corresponding to the phase angle into an array, and calculating the phase zero angle of the outer frame motor. And similarly, calculating the phase zero angle of the inner frame motor to finish calibration. According to the motor phase zero angle measured by the method, compared with a single measurement value, the motor rotates more uniformly and smoothly.

Description

Technical Field

[0001] The invention relates to a method for calibrating the electrical angle of a three-motor inertial system motor, and belongs to the technical field of inertial system calibration. Background Art

[0002] The internal structure of the three-axis laser inertial group is as follows: Figure 1 As shown, the internal gyroscope and gyroscope can be rotated, thereby calibrating the internal sensors of the IMU and improving the IMU output accuracy. The higher the rotation accuracy of the mechanism, the better the IMU calibration. Mechanism rotation requires knowledge of its electrical angle. Manual testing is error-prone and complex. Therefore, a method for automating the electrical angle calibration of the three-axis IMU motor is needed. Summary of the Invention

[0003] The technical problem solved by the present invention is to overcome the deficiencies of the prior art and provide a method for calibrating the electrical angle of a three-inertia motor, which has an automatic calibration function for the electrical angle of the motor.

[0004] The technical solution of the present invention is:

[0005] A method for calibrating the electrical angle of a three-inertia motor includes the following steps:

[0006] (1) Rotate the outer frame to the vicinity of the limit block, control the given motor 0 degree vector d-axis control amount, and pull the outer frame motor to the motor 0 phase point;

[0007] (2) After two seconds, a 60-degree vector d-axis control value is given, after two seconds, a 120-degree vector d-axis control value is given, and after two seconds, a 180-degree vector d-axis control value is given;

[0008] (3) During the given process, the outer frame motor will continuously rotate in one direction to determine whether the motor angle is stuck. If it is stuck, it means that the outer frame has reached the limit block, and then enter step (4);

[0009] (4) At this time, the vector value is given in the reverse direction, and the phase value before the given value is used as the reference, and the value is reduced by 60 degrees each time. When the phase angle is reduced to 0, the mechanical angle value of the outer frame is recorded;

[0010] (5) The mechanical angle value corresponding to the recorded phase angle is stored in the jiaodu

[24] array to calculate the phase zero angle of the outer frame motor;

[0011] (6) Calculate the phase zero angle of the inner frame according to the method of steps (1) to (5) above to complete the calibration.

[0012] Furthermore, the D-axis control quantity of the motor is the magnetic field force generated by the stator coil parallel to the rotor virtualized by the FOC motor control algorithm.

[0013] Furthermore, the 0 phase point is the position where the electrical angle is 0 in the motor FOC control algorithm, that is, the phase angle is 0.

[0014] Furthermore, for a three-phase motor with N pole pairs, a 60-degree phase angle rotation increases the motor's mechanical angle by 60 / N. Each phase angle is 60 degrees apart, and a cycle is 360 degrees. The phase angle changes six times, and the mechanical angle increases by (60 / N)*6. A 180-degree mechanical angle rotation corresponds to 24 phase angles.

[0015] Furthermore, the phase zero angle of the motor is calculated using the following formula:

[0016] ∑ 23 0(jiaodu[i]-i*7.5) / 24,

[0017] Where i = 0, 1, 2,…, 23.

[0018] In a second aspect, the present invention further proposes a processor, characterized in that the processor is used to run a program, wherein the method described is executed when the program is run.

[0019] In a third aspect, the present invention further provides a computer program product, which implements the method when executed by a processor.

[0020] The beneficial effects of the present invention compared with the prior art are:

[0021] (1) The method of the present invention can automatically calibrate the electrical angle value of the motor frame;

[0022] (2) The method of the present invention can automatically calibrate the motor electrical angle of a dual-axis mechanical structure with a limiting measure;

[0023] (3) The electrical angle calibration result of the method of the present invention is more accurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 Schematic diagram of the internal frame structure of the three-autonomous laser inertial group. DETAILED DESCRIPTION

[0025] The specific embodiments of the present invention are further described in detail below with reference to the accompanying drawings.

[0026] The internal structure of the three-axis laser inertial group is as follows: Figure 1 As shown in the figure, the three-autonomous laser inertial group includes an inertial group box 1, an outer frame motor 2, an outer frame frame 3, an inner frame motor 4, an inner frame rotary transformer 5, an inner frame frame 6 and an outer frame rotary transformer 7; by controlling the rotation of the inner frame and the outer frame, the rotation of the internal gyroscope and the adding table can be achieved, so that the internal sensors of the inertial group can be calibrated to improve the output accuracy of the inertial group.

[0027] The three-axis laser inertial system has a dual-motor structure, with internal limit blocks inside both the outer and inner frames to limit the frame's rotation angle. When measuring the motor's electrical angle, the limit blocks must be considered. Therefore, a program for automatically measuring the electrical angle was developed, and a method for calibrating the electrical angle of the three-axis inertial system motor was proposed.

[0028] The method for calibrating the motor electrical angle includes the following steps:

[0029] A method for calibrating the electrical angle of a three-inertia motor includes the following steps:

[0030] (1) Rotate the outer frame to the vicinity of the limit block, control the given motor 0 degree vector d-axis control amount, and pull the outer frame motor to the motor 0 phase point;

[0031] The D-axis control quantity of the motor is the magnetic field force generated by the stator coil parallel to the rotor virtualized by the FOC motor control algorithm; the 0 phase point is the position where the electrical angle is 0 in the motor FOC control algorithm, that is, the phase angle is 0.

[0032] (2) After two seconds, a 60-degree vector d-axis control value is given, after two seconds, a 120-degree vector d-axis control value is given, and after two seconds, a 180-degree vector d-axis control value is given;

[0033] (3) During the given process, the outer frame motor will continuously rotate in one direction to determine whether the motor angle is stuck. If it is stuck, it means that the outer frame has reached the limit block, and then enter step (4);

[0034] (4) At this time, the vector value is set in the reverse direction, and the phase value before the setting is used as the reference, and the value is reduced by 60 degrees each time. When the phase angle is reduced to 0, the mechanical angle value output by the outer frame rotary transformer is recorded;

[0035] For a three-phase motor with N pole pairs, if the phase angle rotates 60 degrees, the motor's mechanical angle increases by 60 / N. Each phase angle is 60 degrees apart, and one cycle is 360 degrees. The phase angle changes six times, and the mechanical angle increases by (60 / N)*6. A mechanical angle rotation of 180 degrees corresponds to 24 phase angles.

[0036] (5) The mechanical angle value corresponding to the recorded phase angle is stored in the jiaodu

[24] array to calculate the phase zero angle of the outer frame motor;

[0037] ∑ 23 0(jiaodu[i]-i*7.5) / 24,

[0038] Where i = 0, 1, 2,…, 23.

[0039] (6) Calculate the phase zero angle of the inner frame according to the method of steps (1) to (5) above to complete the calibration.

[0040] Example:

[0041] The motor's D-axis control value is set at phase angles of 0, 60, 120, 180, and so on. During this setting process, the motor will continuously move in one direction. When the motor reaches a stop block, it will pause. Therefore, the motor angle is checked for lag. If so, it indicates that the stop block has been reached. At this point, the vector value is set in the reverse direction, subtracting 60 degrees from the previous phase value. When the phase angle reaches 0, the current motor mechanical angle value is recorded.

[0042] Taking an 8-pole three-phase motor as an example, if the phase angle rotates 60 degrees, the motor mechanical angle increases by 7.5 degrees, that is, 60 / 8=7.5.

[0043] Each phase angle is 60 degrees apart, and one cycle is 360 degrees. The phase angle changes 6 times, and the mechanical angle increases by 45 degrees. That is, 7.5*6=45. The mechanical angle rotates 180 degrees, corresponding to 24 phase angles.

[0044] The mechanical angles corresponding to the 24 phase angles are stored in jiaodu

[24] , and the zero phase angle can be calculated as ∑ 23 0(j iaodu[i]–i*7.5) / 24.

[0045] The above strategy can measure the motor phase zero angle. Compared with a single measurement value, this value indicates that the motor rotation is more uniform and smooth.

[0046] Parts of the present invention that are not described in detail belong to common knowledge among those skilled in the art.

Claims

1. A method for calibrating the electrical angle of a three-inertia motor, characterized in that: include: (1) Rotate the outer frame to the vicinity of the limit block, control the given motor 0 degree vector d-axis control amount, and pull the outer frame motor to the motor 0 phase point; (2) After two seconds, a 60-degree vector d-axis control value is given, after two seconds, a 120-degree vector d-axis control value is given, and after two seconds, a 180-degree vector d-axis control value is given; (3) During the given process, the outer frame motor will continuously rotate in one direction to determine whether the motor angle is stuck. If it is stuck, it means that the outer frame has reached the limit block, and then enter step (4); (4) At this time, the vector value is given in the reverse direction, and the phase value before the given value is used as the reference, and the value is reduced by 60 degrees each time. When the phase angle is reduced to 0, the mechanical angle value of the outer frame is recorded; (5) The mechanical angle value corresponding to the recorded phase angle is stored in the jiaodu[24] array to calculate the phase zero angle of the outer frame motor; (6) Calculate the phase zero angle of the inner frame according to the method of steps (1) to (5) above to complete the calibration.

2. The method for calibrating the electrical angle of a three-inertia motor according to claim 1, characterized in that: The D-axis control quantity of the motor is the magnetic field force generated by the stator coil parallel to the rotor virtualized by the FOC motor control algorithm.

3. The method for calibrating the electrical angle of a three-inertia motor according to claim 1, characterized in that: The 0 phase point is the position where the electrical angle is 0 in the motor FOC control algorithm, that is, the phase angle is 0.

4. The method for calibrating the electrical angle of a three-inertia motor according to claim 1, characterized in that: For a three-phase motor with N pole pairs, the phase angle rotates 60 degrees and the motor mechanical angle increases by 60 / N.

5. The method for calibrating the electrical angle of a three-inertia motor according to claim 4, characterized in that: Each phase angle is 60 degrees apart, one cycle is 360 degrees, the phase angle changes 6 times, and the mechanical angle increases by (60 / N)*6.

6. The method for calibrating the electrical angle of a three-inertia motor according to claim 5, characterized in that: A mechanical rotation of 180 degrees corresponds to 24 phase angles.

7. The method for calibrating the electrical angle of a three-inertia motor according to claim 6, characterized in that: The calculation of the motor phase zero angle is achieved through the following formula: ∑ 23 0(jiaodu[i]-i*7.5) / 24, Where i = 0, 1, 2,…, 23.

8. A processor, characterized in that: The processor is configured to run a program, wherein the program executes the method according to any one of claims 1 to 7 when running.

9. A computer program product, characterized in that When the computer program product is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

Images