JPH05300779A - Controlling method for servo motor - Google Patents

Abstract

PURPOSE:To allow both resolution of positioning a servo driver for controlling a servo motor and a high speed rotation to be compatible. CONSTITUTION:A direction of an AB phase pulse 13 to be output from a detector 12 mounted in a servo motor 11 is decided by an AB phase direction discriminator. 14, which outputs an up-down signal 15. A direction of a UVW phase pulse 16 to be output from the detector 12 is decided by a UVW phase direction discriminator 17, which outputs a clear load signal 18. An address having a counted value 20 of a counter 19 for counting the signal 15 while controlling it by the signal 18 as a lower significant bit and the pulse 16 as an upper significant bit is input to a ROM 21 to be converted to pole data 22. The data 22 and the pulse 16 are read by a microcomputer 23, and a controlling method is so switched as to control conduction of a rectangular wave at the time of rotating at a high speed and to control conduction of a sine wave at the time of rotating at a low speed according to speed data 26 to be output from a speed calculator 25 contained in the microcomputer 23.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a servo motor control method.

[0002]

2. Description of the Related Art In a conventional servomotor control method, rectangular wave energization control using a UVW phase pulse 16 output from a detector 12 attached to a servomotor 11,
Alternatively, the UVW phase pulse 16 and A output by the detector 12
The servo motor 11 is controlled by the sine wave energization control using the B-phase pulse 13.

[0003]

However, in this conventional servo motor control method, the servo motor 1 is used.
While the UVW phase pulse 16 output from the detector 12 per one rotation is 1 to 16 pulses,
Since the B-phase pulse 13 is 500 to 5000 pulses, the positioning resolution is at most 3.75 degrees in the rectangular wave energization control, and the high-speed rotation is converted to the AB phase pulse frequency in the sine wave energization control at most. 600 kH
up to z. Therefore, the present invention makes it possible to achieve both positioning resolution and high-speed rotation.

[0004]

In the servo motor control method of the present invention, the direction of the AB phase pulse 13 output by the detector 12 attached to the servo motor 11 is discriminated and converted into an up / down signal 15 for detection. The direction of the UVW phase pulse 16 output from the container 12 is discriminated and converted into a clear load signal 18, and the up / down signal 15 is counted while being controlled by the clear load signal 18. An address having the counted value as the lower bit and the UVW phase pulse 16 as the upper bit is input to the ROM 21 to be converted into the magnetic pole data 22, and the UVW phase pulse 16 is counted and converted into the rotation speed. A switching point is provided for the number of rotations of the servo motor 11, and the switching point and the number of rotations are compared to perform rectangular wave energization control during high speed rotation, and sine wave energization control during low speed rotation.

[0005]

In the servo motor control method of the present invention configured as described above, the UVW phase pulse 16 is counted to calculate the rotation speed of the servo motor 11, and the rectangular wave energization control is performed during high speed rotation. By performing sine wave energization control during low-speed rotation, it is possible to achieve both positioning resolution and high-speed rotation.

[0006]

1 is an example of a servo motor control method according to the present invention, which has both a sine wave energization control and a rectangular wave energization control.

In FIG. 1, a detector 12 attached to a servomotor 11 outputs an AB phase pulse 13 and a UVW phase pulse 16. The AB phase pulse 13 is discriminated in direction by the AB phase direction discriminator 14, converted into an up / down signal 15, and input to the counter 19. Further, the UVW phase pulse 16 is discriminated by the UVW phase direction discriminator 17, converted into a clear load signal 18, and input to the counter 19.

The count value 20 of the counter 19 and the UVW phase pulse 16 are input to the ROM 21 and converted into magnetic pole data 22, and the magnetic pole data 22 and the UVW phase pulse 16 are input to the microcomputer 23.

Further, the UVW phase pulse 16 is applied to the speed calculator 2
5 is converted into speed data 26, and this speed data 2
6 is compared with the switching point 27 shown in FIG. 2, if the speed data 26 is larger, rectangular wave energization control is performed, and if the speed data 26 is smaller, sine wave control is performed.

[0010]

According to the present invention, by switching between the rectangular wave energization control and the sine wave energization control as described above, it is possible to achieve both positioning resolution and high-speed rotation.

[Brief description of drawings]

FIG. 1 is a block diagram showing an example of a servo motor control method of the present invention.

FIG. 2 is a diagram showing an example of switching of the servo motor control method of the present invention.

[Explanation of symbols]

 11 Servo Motor 12 Detector 13 AB Phase Pulse 14 AB Phase Direction Discriminator 15 Up / Down Signal 16 UVW Phase Pulse 17 UVW Phase Direction Discriminator 18 Clear Load Signal 19 Counter 20 Count Value 21 ROM 22 Magnetic Pole Data 25 Speed Calculator 26 Speed Data 27 Switching point

Claims (1)

[Claims] 1. A direction of an AB phase pulse output from a detector attached to a servomotor is determined and converted into an up / down signal, and a direction of a UVW phase pulse output from the above detector is determined and converted into a clear load signal. Then, the up / down signal is counted under the control of the clear load signal, magnetic pole data is converted by the counted value and the UVW phase pulse, the UVW phase pulse is converted into speed data, and the speed data is obtained. Is greater than a certain value, rectangular wave energization control is performed on the servo motor, and when the speed data is less than the certain value, sinusoidal wave energization control is performed on the servo motor.