阅读说明：本技术 一种直流力矩电机启动过程精确控制方法 (Method for accurately controlling starting process of direct-current torque motor ) 是由 周腊梅 崔雪兵 孟凡强 于 2020-11-25 设计创作，主要内容包括：本发明公开了一种直流力矩电机启动过程精确控制方法,针对直流力矩电机启动力矩大问题,首先,根据系统各项性能指标确定电机启动的位置角,然后,判断电机是否启动,若没有启动,控制主令采用比例,积分输出；同时给出比例、积分参数的选取方法；随后对控制主令进行限幅处理；最后,电机启动后,通过固定主令输出控制电机以稳定的速度转动。该方法能够有效保证直流力矩电机在规定时间内正常启动,提高系统可靠性。本发明方法具有下列优点：具有实现方法简单,计算数据准确,在工程实践中有效等优点。(The invention discloses a method for accurately controlling the starting process of a direct-current torque motor, which aims at the problem of large starting torque of the direct-current torque motor, and comprises the steps of firstly determining the starting position angle of the motor according to various performance indexes of a system, then judging whether the motor is started, and if the motor is not started, controlling a main command to adopt proportional and integral output; simultaneously, a selection method of proportional and integral parameters is given; then, carrying out amplitude limiting processing on the control master; and finally, after the motor is started, the motor is controlled to rotate at a stable speed through the fixed master output. The method can effectively ensure that the direct-current torque motor is normally started within the specified time, and the system reliability is improved. The method of the invention has the following advantages: the method has the advantages of simple implementation method, accurate calculation data, effectiveness in engineering practice and the like.)

1. A method for accurately controlling the starting process of a direct current torque motor is characterized by comprising the following steps:

step 1: the motor and the position sensor are in meshing transmission through a gear, the position information of the position sensor is read, and the state of the motor is judged according to the position information;

the code number corresponding to one tooth rotated by the position sensor is F:

wherein A is the minimum angle of rotation of the position sensor; d is the angle required for the position sensor to rotate one tooth;

step 2, when the motor is not started, if the output angle of the position sensor is smaller than D, the control master command of the motor adopts proportional and integral output;

the proportionality coefficient is set as G: g ═ hxf; wherein h is a preset proportional margin;

and step 3: and (3) carrying out amplitude limiting on the integral term, and setting the maximum value of integral amplitude limiting as I: i is gxf × j;

wherein j is a preset integral amplitude limiting margin;

step 4, acquiring a current position angle xpst, wherein the position angle at the previous moment is xpst0, and the current angle difference ax is xpst-xpst 0; presetting an initial value of an integral output xiout;

step 5, judging whether ax is (-F, F), if yes, outputting bx in proportion to ax multiplied by G, increasing ax of integral output xiout, and entering step 6; otherwise, let ax be F, let bx be ax × F, and integral output xiout be 0, and go to step 7;

step 6, judging whether the integral output xiout is in an integral amplitude limiting range (-I, I), entering a step 7, and otherwise, enabling the integral output xiout to be equal to the integral amplitude limiting range I;

step 7, acquiring the output of the position sensor by a data acquisition chip to obtain a final output xiout 0; the acquisition precision of the data acquisition chip is l; then xiout0 is bx + xiout × l.

2. The method of claim 1, wherein in step 2, the minimum angle a of rotation of the position sensor is taken as:

wherein A is the minimum rotation angle of the position sensor; b is a theoretical value of rotation; c is the data conversion code number; k is a mechanical transmission ratio;

angle D required for the position sensor to rotate one tooth:

where E is the total number of teeth in the position sensor gear.

3. The method according to claim 1 or 2, wherein the determining the motor status by the position information is specifically:

the motor is in a working state after being electrified, and the working state comprises a rapid rotation state, a slow rotation state and a static state;

judging to obtain the motor speed according to the position information, and if the motor speed is higher than half of the rated rotation speed of the motor, enabling the motor to be in the rapid rotation state;

if the speed of the motor is lower than half of the rated rotating speed of the motor and is higher than the lowest speed threshold value, the motor is in the slow rotating state;

and if the speed of the motor is lower than the minimum speed threshold value, the motor is in the static state.

4. The method of claim 1, wherein h is 1/2.

5. The method of claim 1, wherein j-4.

Technical Field

The invention relates to the technical field of motor control of a servo control system, in particular to a method for accurately controlling a starting process of a direct-current torque motor.

Background

At present, in products such as a seeker servo platform, a photoelectric tracker and the like in China, a direct-current torque motor is mostly adopted as an execution mechanism, the direct-current torque motor is an ideal choice for directly driving servo application, and the speed and the position precision are improved to the maximum extent while the size, the weight, the power and the response time are reduced to the greatest extent. The dc torque motor provides a servo drive that can be directly connected to the drive load.

The direct current torque motor can provide ultra-low rotating speed and high torque, or high response speed and optimal torque for an ideal positioning and speed control system; has the following characteristics: frameless mounting mode and optionally large torque range; high torque to inertia ratio, fast start/stop and high acceleration; high torque to power ratio, low power input requirement; a low electrical time constant is a good command response to all operating speeds; the linear torque responds to the input current and speed, and no dead angle exists; long-term operational reliability; the precision is high, and a gear system is not needed even at extremely low rotating speed; the operation is quiet and stable; the design is compact and the adaptability is strong; the permanent magnet material, the number of lamination slots, the thickness of the iron core, the power supply voltage and the like can be designed as required.

The permanent-magnet DC torque motor belongs to a servo motor with low rotating speed, large torque and locked rotor,

the brush motor is low in cost, simple in structure, large in starting torque, wide in speed regulation range, easy to control and convenient to maintain (carbon brush replacement), needs maintenance, can generate electromagnetic interference and has requirements on the environment.

The starting process of the direct current torque motor comprises the following steps: the method comprises five parts of starting, accelerating, running, decelerating and stopping, wherein the starting is the first part of the work of the direct current torque motor, if the starting torque is too large, the servo system cannot be started, or the starting time is too long, and the problems of false alarm and the like are brought to the system.

Therefore, a control method for a dc torque motor is needed to enable the dc torque motor to be normally started within a specified time.

Disclosure of Invention

In view of this, the invention provides an accurate control method for a starting process of a direct current torque motor, which can effectively ensure that the direct current torque motor is normally started within a specified time, and improve the reliability of a system.

In order to achieve the purpose, the technical scheme of the invention comprises the following steps:

step 1: the motor and the position sensor are in meshed transmission through the gear, the position information of the position sensor is read, and the state of the motor is judged according to the position information.

The code number corresponding to one tooth rotated by the position sensor is F:

wherein A is the minimum angle of rotation of the position sensor; d is the angle required for the position sensor to rotate one tooth.

And 2, when the motor is not started, if the output angle of the position sensor is smaller than D, the control master command of the motor adopts proportional and integral output.

The proportionality coefficient is set as G: g ═ hxf; where h is a preset proportional margin.

And step 3: and (3) carrying out amplitude limiting on the integral term, and setting the maximum value of integral amplitude limiting as I: i ═ gxf × j.

Where j is a preset integral clipping margin.

Step 4, acquiring a current position angle xpst, wherein the position angle at the previous moment is xpst0, and the current angle difference ax is xpst-xpst 0; the initial value of the integrated output xiout is set in advance.

Step 5, judging whether ax is (-F, F), if yes, outputting bx in proportion to ax multiplied by G, increasing ax of integral output xiout, and entering step 6; otherwise, let ax be F, let bx be ax × F, and integral output xiout be 0, and proceed to step 7.

And 6, judging whether the integral output xiout is in the integral amplitude limiting range (-I, I), entering a step 7, and otherwise, enabling the integral output xiout to be equal to the integral amplitude limiting range I.

Step 7, acquiring the output of the position sensor by a data acquisition chip to obtain a final output xiout 0; the acquisition precision of the data acquisition chip is l; then xiout0 is bx + xiout × l.

Further, in step 2, the minimum angle a of rotation of the position sensor is taken:

wherein A is the minimum rotation angle of the position sensor; b is a theoretical value of rotation; c is the data conversion code number; k is the mechanical transmission ratio.

Angle D required for the position sensor to rotate one tooth:

where E is the total number of teeth in the position sensor gear.

Further, the motor state is judged through the position information, and the method specifically comprises the following steps:

the motor is in a working state after being electrified, and the working state comprises a rapid rotation state, a slow rotation state and a static state.

And judging to obtain the motor speed according to the position information, and if the motor speed is higher than half of the rated rotating speed of the motor, enabling the motor to be in a rapid rotating state.

And if the speed of the motor is lower than half of the rated rotating speed of the motor and higher than the minimum speed threshold value, the motor is in a slow rotating state.

And if the speed of the motor is lower than the minimum speed threshold value, the motor is in a static state.

Further, wherein h is 1/2.

Further, where j is 4.

Has the advantages that:

the embodiment of the invention provides an accurate control method for a starting process of a direct-current torque motor, aiming at the problem of large starting torque of the direct-current torque motor, firstly, determining a starting position angle of the motor according to various performance indexes of a system, then, judging whether the motor is started, and if the motor is not started, controlling a main command to adopt proportional and integral output; simultaneously, a selection method of proportional and integral parameters is given; then, carrying out amplitude limiting processing on the control master; and finally, after the motor is started, the motor is controlled to rotate at a stable speed through the fixed master output. The method can effectively ensure that the direct-current torque motor is normally started within the specified time, and the system reliability is improved. The method of the invention has the following advantages: the method has the advantages of simple implementation method, accurate calculation data, effectiveness in engineering practice and the like.

Drawings

Fig. 1 is a flowchart of a control process of a bearing mounting angle in a motor starting process in embodiment 1 of the present invention;

fig. 2 is a flowchart of a control process of the pitch setting angle in the motor starting process in embodiment 2 of the present invention.

Detailed Description

The invention is described in detail below by way of example with reference to the accompanying drawings.

A current loop, a speed loop, a position loop and a tracking loop are usually designed in the servo control system, wherein the current loop is the innermost loop, the speed loop is the middle loop, the position loop is the secondary outer loop, and the tracking loop is the outer loop. Because the current loop and the speed loop are arranged in the inner loop and have higher corresponding speeds, namely, the speed of responding to the system instruction is high, and the speed of responding to the system disturbance is also high (response is too fast and uncontrollable), the tracking loop is arranged in the outermost loop, the response speed is slowest, and the tracking loop is directly controlled by the tracker, the invention hopes to be controlled by a servo controller, so the invention selects the position loop as a feedback loop to improve the control algorithm.

Embodiment 1, infrared imaging seeker optics cabin, course motor parameters:

armature resistance: (21. + -. 2.7) Ω (at 20 ℃ C.)

Maximum no-load speed

When the voltage is 22.5V, the no-load rotation speed of the positive direction and the negative direction is (410 +/-41) r/min.

Continuous locked-rotor torque and continuous locked-rotor voltage

When the motor is applied with continuous locked-rotor current of 1.06A,

continuous locked-rotor torque is more than or equal to 0.48N.m

The continuous locked-rotor voltage is (22.5V +/-2.3) V

Locked-rotor torque sensitivity: not less than 0.45N.m/A

Starting voltage

No-load starting voltage is less than or equal to 1.5V, and forward and reverse starting voltage difference is less than or equal to 0.2V

Torque ripple coefficient: less than or equal to 10 percent

Electrical time constant: less than or equal to 1ms (reference value)

The specific control flow chart is shown in FIG. 1, and the control process flow chart of the course installation angle in the motor starting process in FIG. 1

Step 1: reading the position information of a position sensor, judging the state of a motor, and determining the starting position angle of the motor according to various performance indexes of the system:

in the control field, it is common to select an angle sensor mechanical rotation gear to rotate one tooth as a motor movement sign, and the angle of rotation of the gear corresponding to the position sensor rotation is calculated as follows:

taking the minimum angle A of rotation of the position sensor:

wherein A is the minimum rotation angle of the position sensor; b is a theoretical value of rotation, in this embodiment 1, the theoretical value of rotation is 360 °, that is, B is 360 °; c is the number of data conversion codes, the number of data conversion codes in the invention is the acquisition precision of the data acquisition chip of the position sensor, and when the 14-bit data acquisition chip is adopted in the embodiment 1 of the invention, the number of data conversion codes is 2¹⁴(ii) a K is a mechanical transmission ratio, the motor and the position sensor are in meshing transmission through gears in the embodiment of the invention, wherein the mechanical transmission ratio is the ratio of the number of teeth of the gears of the motor to the number of teeth of the rotating gears of the position sensor, and the value of the mechanical transmission ratio K is 2.51 in the embodiment 1 of the invention. ThenCode/code.

Angle D required for the position sensor to rotate one tooth:

wherein E is the total number of teeth of the position sensor gear, and the value of E is 57 in this embodiment 1. Then

The number of codes corresponding to one tooth rotated by the position sensor is F:

in example 1 of the present invention

In engineering applications, F may be chosen to be 120.

Step 2: if the motor is not started, namely the output angle of the position sensor is smaller than an angle D required by the rotation of one tooth, the control master adopts proportional and integral output;

the proportionality coefficient is set as G: g ═ hxf; where h is a preset proportional margin, the value of h may be set empirically in the embodiment of the present invention, for example, h may be set to 1/2, and G may be 60 in embodiment 1.

And step 3: and (3) carrying out amplitude limiting on the integral term, wherein the maximum value of the integral amplitude limiting is I: i is gxf × j;

where j is a preset integral clipping margin, the value of j may be set empirically in the embodiment of the present invention, and may be set to be j ≈ 30000 in embodiment 1 of the present invention, for example.

Step 4, acquiring a current position angle xpst, wherein the position angle at the previous moment is xpst0, and the current angle difference ax is xpst-xpst 0; presetting an initial value of an integral output xiout;

step 5, judging whether ax is (-F, F), which is (-120,120) in the embodiment of the invention, if yes, outputting bx in proportion to ax × G, increasing ax of integral output xiout, and entering step 6; otherwise, let ax be F, let bx be ax × F, and integral output xiout be 0, and go to step 7;

step 6, judging whether the integral output xiout is in an integral amplitude limiting range (-I, I), which is (-30000,30000) in the embodiment of the invention, then entering step 7, otherwise, making the integral output xiout equal to the integral amplitude limiting range I;

step 7, acquiring the output of the position sensor by a data acquisition chip to obtain a final output xiout 0; the acquisition precision of the data acquisition chip is l; then xiout0 is bx + xiout × l.

Embodiment 2, infrared imaging seeker optics cabin, the pitch motor parameter is as follows:

armature resistance (36 + -4.5) omega (at 20 deg.C)

Maximum no-load rotation speed (r/min)

When the voltage is 60V, the no-load rotation speed of the positive direction and the negative direction is (580 +/-58) r/min.

Continuous locked-rotor torque and continuous locked-rotor voltage

When the motor is applied with a continuous locked-rotor current of 0.64A,

continuous locked-rotor torque is more than or equal to 0.56N.m

The continuous locked-rotor voltage is (25 +/-2.5) V

Peak locked rotor torque and peak locked rotor voltage

At a peak locked-rotor current of 1.54A,

peak locked-rotor torque is more than or equal to 1.35N.m

The peak locked-rotor voltage is (60 +/-6) V

The sensitivity of the locked-rotor torque is more than or equal to 0.875N.m/A

Starting voltage: no-load starting voltage is less than or equal to 1.9V, and forward and reverse starting voltage difference is less than or equal to 0.15V

Torque ripple coefficient: less than or equal to 7 percent

Electrical time constant: less than or equal to 1ms (reference value)

Step 1: reading the position information of a position sensor, judging the state of a motor, and determining the starting position angle of the motor according to various performance indexes of the system:

in the control field, it is common to select an angle sensor mechanical rotation gear to rotate one tooth as a motor movement sign, and the angle of rotation of the gear corresponding to the position sensor rotation is calculated as follows:

taking the minimum angle A of rotation of the position sensor:

wherein A is the minimum rotation angle of the position sensor; b is a theoretical value of rotation, in this embodiment 2, the theoretical value of rotation is 360 °, that is, B is 360 °; c is the number of data conversion codes, which is the acquisition precision of the data acquisition chip of the position sensor in the present invention, in embodiment 1 of the present inventionWhen a 14-bit data acquisition chip is adopted, the number of data conversion codes is 2¹⁴(ii) a K is a mechanical transmission ratio, the motor and the position sensor are in meshing transmission through gears in the embodiment of the invention, wherein the mechanical transmission ratio is the ratio of the number of teeth of the gears of the motor to the number of teeth of the rotating gears of the position sensor, and the value of the mechanical transmission ratio K is 3.76 in the embodiment 2 of the invention. ThenCode/code.

Angle D required for the position sensor to rotate one tooth:

where E is the total number of teeth of the position sensor gear, and the value of E is 58 in this embodiment 2. Then

The number of codes corresponding to one tooth rotated by the position sensor is F:

in example 1 of the present invention

In engineering applications, F may be chosen to be 100.

Step 2: if the motor is not started, namely the output angle of the position sensor is smaller than the angle required by the rotation of one tooth, the control master adopts proportional and integral output;

the proportionality coefficient is set as G: g ═ hxf; where h is a preset proportional margin, the value of h may be set empirically in the embodiment of the present invention, for example, h may be set to 1/2, and G may be set to 50 in this embodiment 2.

And step 3: and (3) carrying out amplitude limiting on the integral term, wherein the maximum value of the integral amplitude limiting is I: i is gxf × j;

for example, j ≈ 4 may be set, and then I ≈ 20000 in embodiment 2 of the present invention.

Step 4, acquiring a current position angle xpst, wherein the position angle at the previous moment is xpst0, and the current angle difference ax is xpst-xpst 0; presetting an initial value of an integral output xiout;

step 5, judging whether ax is (-F, F), which is (-100,100) in the embodiment of the present invention, if yes, outputting bx in proportion to ax × G, increasing xiout in integral output to ax, and entering step 6; otherwise, let ax be F, let bx be ax × F, and integral output xiout be 0, and go to step 7;

step 6, judging whether the integral output xiout is in an integral amplitude limiting range (-I, I), which is (-20000,20000) in the embodiment of the invention, then entering step 7, otherwise, making the integral output xiout equal to the integral amplitude limiting range I;

step 7, acquiring the output of the position sensor by a data acquisition chip to obtain a final output xiout 0; the acquisition precision of the data acquisition chip is l; then xiout0 is bx + xiout × l.

The specific control flow is shown in fig. 2.

In summary, the above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.