JP2002142481A - Method for controlling rotation of dc motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve a problem of follow-up of rotation being not measured at the time of high speed rotation of a motor exceeding a predetermined level when the motor is rotated at a high speed by monitoring the rotational speed of the motor normally at the input. SOLUTION: When a DC motor 1 is started, a positional detection signal from a Hall element (photocoupler) 2 is synchronized with the edge of an input pulse by an OR circuit 3 and inputted, as one input, to an interruption circuit 5. Using that signal, an output pattern control block 7 determines a feedback output to UVW (/UVW) phases. On the other hand, with regard to a voltage command, input capture data 8 triggered by an interruption signal 5 is converted, at a voltage command section 9, into a PWM output.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention uses a microcomputer or the like to detect the number of rotations of a motor and to reduce the number of rotations to 3 so that smooth variable speed control can be performed even during high-speed rotation.
A motor control method that captures the OR of a phase input as data using an interrupt, detects the rotation speed within one rotation of the motor, and minimizes the hardware resources of the microcomputer to efficiently rotate the motor. It is.

[0002]

2. Description of the Related Art A conventional DC motor control method will be described below.

FIG. 1 shows an overall configuration diagram. FIG. 2 shows the flow of the software.

In FIG. 1, when the DC motor starts rotating by some starting, a three-phase (UV) is detected by a motor position detector (constituted by a photocoupler) installed on the motor.
W) An input pattern is obtained. At this time, the microcomputer reads back the level connected to the I / O of the microcomputer as in the algorithm shown in FIG.

As a result, as shown in FIG. 3, the current motor position is detected by recognizing a change point of the three-phase input, and the three-phase output corresponding to the input pattern is performed to rotate the motor. Was. Further, in order to detect the rotation direction, it is necessary to input the rotation direction information to another port.

[0006]

However, in the above-mentioned conventional configuration, since the rotation signal of the motor is monitored by a normal input, when the motor is rotated at a high speed, the rotation speed of the motor exceeding a certain fixed speed is high. At times, it was not possible to measure the rotation.

When detecting the position of the motor, FIG.
It has been confirmed that the monitoring of the change point as shown in (1) consumes a lot of hardware resources of the microcomputer.

[0008]

In order to achieve this object, according to the DC motor rotation control method of the present invention, as shown in FIG. Recognize it as an external interrupt signal.

Further, the block comprises a block for generating a three-phase output pattern for recognizing and feeding back a change point of the three-phase input by software using an interrupt signal generated by this input as a trigger. Further, since there is one input, the rotation direction is determined by pattern recognition in the interrupt processing.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 5 is a block diagram showing a DC motor rotation control method according to the embodiment of the present invention. In FIG. 5, 1 is an equivalent block of a DC motor, 2 is a motor position detector (constituted by a photocoupler), 3 is an OR circuit for converting a three-phase input into one input, and 4 is a microcomputer for processing them. 5 is an external interrupt circuit, 6 is a timer block, 7 is a block that controls a three-phase output pattern, 8 is a block that converts the value of a timer (binary counter) captured at the timing of an external interrupt into a time component, and 9 is This block calculates and outputs the time-converted data as a voltage command to the motor. First, when the DC motor 1 is started, a position detection signal is input from the Hall element (photocoupler) 2. The three-phase signal at this time is input to the external interrupt circuit 5 which is a peripheral function of the microcomputer 4 as one input signal in synchronization with the edge of the input pulse by the OR circuit 3. Using this signal, the output pattern control block 7 determines the feedback output to the UVW (/ UVW) phase. On the other hand, with regard to the voltage command, the input capture block 8 using the interrupt signal as a trigger is controlled by the timer 6 and converted into the PWM output by the voltage command unit 9.

[0012]

As described above, according to the embodiment, when the conventional motor is rotated at a high speed, one second per second as shown in FIG.
In the motor that rotates at 000 rpm, the speed could not be followed due to the rapid rotation speed change, but the speed could be followed in response to the change in the average speed as shown in FIG. Further, as shown in FIG. 5, the system configuration was simplified, and the I / O of the microcomputer was effectively reduced.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a DC motor rotation control according to a conventional method.

FIG. 2 is a flowchart of software according to a conventional method.

FIG. 3 is a three-phase input pattern diagram

FIG. 4 is a diagram in which a three-phase input according to the present invention is captured by an OR circuit;

FIG. 5 is a configuration diagram of a DC motor rotation control according to the present invention.

FIG. 6 is a diagram in which the high-speed motor rotation cannot follow the conventional method.

FIG. 7 is a diagram showing a state in which a motor follows a high-speed rotation according to the present invention.

[Explanation of symbols]

Reference Signs List 1 Equivalent block of DC motor 2 Motor position detector (photocoupler) 3 OR circuit for converting three-phase input to one input 4 Whole microcomputer performing arithmetic processing 5 External interrupt circuit 6 Timer block 7 Three-phase output Block that controls the pattern 8 Block that converts the value of the timer (binary counter) captured at the timing of the external interrupt into a time component 9 Block that calculates and outputs the time-converted data as a voltage command to the motor

Claims (2)

[Claims] When driving a DC motor using an 8-bit microcomputer or the like, a three-phase signal input from a motor position detector is formed into one input pattern using an OR circuit or the like. In order to smoothly follow the motor high-speed rotation operation, the output pattern of feedback is determined in the external interrupt processing of the microcomputer.
C motor rotation control method. 2. A rotation speed within one rotation of a motor is detected from an external three-phase input signal by using an input capture function of a microcomputer. A DC motor rotation control method in which a three-phase input is assigned to one interrupt input when an input terminal of a microcomputer or the like is insufficient, and a simple circuit is configured by recognizing an interrupt pattern.