JPH07274578A - Speed controller for motor - Google Patents

Abstract

PURPOSE:To provide a speed controller for a motor having characteristics, in which there is no unevenness of rotational speed. CONSTITUTION:A speed error detector 4 compares a rotational period signal from a frequency generator 3 and a target period signal and outputs an error signal, and a speed control circuit 5 outputs a torque signal to an adder 10 so that the error signal of the speed error detector 4 is eliminated. A torque pattern generating circuit 9 outputs the torque pattern signal of a pattern denying the torque ripple of a motor 1 to the adder 10 while being synchronized with the output signal of a conduction synthetic circuit 8 and the output signal of the frequency generator 3. A driver circuit 2 generates torque corresponding to the signal of the adder 10 in the motor 1, thus preventing the effect of the torque ripple, then acquiring a speed controller for the motor having excellent characteristics, in which there is no rotational unevenness.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a speed control device for a motor used in OA equipment or audio / video equipment.

[0002]

2. Description of the Related Art In recent years, as the density of media has increased in recording / reproducing devices of OA equipment, the speed control of motors has been required to be highly accurate.

A conventional speed control device for a motor will be described below. FIG. 4 shows a conventional motor speed control device. In FIG. 4, 1 is a motor composed of rotating permanent magnets magnetized with multiple poles and an armature, 2 is a drive circuit, 3 is a frequency generator, 4 is a speed error detection circuit, 5 is a speed control circuit, and 6 is position detection. The circuit, 7 is an energization switching circuit.

The operation of the motor speed control device constructed as described above will be described below. The rotation cycle signal of the motor detected by the frequency generator 3 is compared with the target cycle by the speed error detection circuit 4, and the speed error signal is output. The speed control circuit 5 outputs a torque signal to the drive circuit 2 so as to eliminate the speed error signal. The position detector 6 outputs the position information of the permanent magnet and the armature of the motor 1 to the energization switching circuit 7, and the energization switching circuit 7 drives the energization switching signal for switching the energization of each coil of the motor 1. Output to circuit 2.
The drive circuit 2 drives the motor 1 based on the torque signal from the speed control circuit and the energization switching signal of the energization switching circuit 7 to rotate the motor 1 at a substantially constant speed.

[0005]

However, in the above-mentioned conventional configuration, the torque ripple generated in proportion to the current flowing through the motor causes the torque ripple to be added to the torque due to the speed control, which causes the problem that the rotational speed becomes uneven. Had.

A first object of the present invention is to solve the above-mentioned conventional problems, and to provide a motor speed control device having a simple structure and free from rotational unevenness due to torque ripple when the motor load is constant. With the goal.

A second object of the present invention is to solve the above-mentioned conventional problems, and to provide a motor speed control device which does not cause rotational unevenness due to torque ripple even when the motor load changes. To aim.

[0008]

In order to achieve the first object, a speed control device for a motor having a first structure according to the present invention comprises a motor composed of a multi-pole magnetized permanent magnet and an armature, and an input. A drive circuit that drives the motor according to a signal, a rotation state detector that detects a state corresponding to the rotation speed or rotation cycle of the motor, and a target rotation speed or a target rotation cycle from the output of the rotation state detector A speed error detection circuit that outputs an error signal, a speed control circuit that outputs a torque signal so that the error signal of the speed error detection circuit becomes zero, a rotational position detector that detects the rotational position of the motor, and An energization switching circuit that outputs an energization switching signal from the output of the rotational position detector to the drive circuit and the energization composition circuit; an energization composition circuit that combines the output signals of the energization composition circuit; A torque pattern generation circuit that outputs a torque signal having a predetermined fluctuation pattern in synchronization with the outputs of the electrosynthesis circuit and the rotation state detector, and the output of the speed control circuit and the output of the torque pattern generator are added and driven. It is composed of an adder circuit that outputs to the circuit.

In order to achieve the second object, the speed control device for the motor according to the second structure of the present invention is arranged such that the motor composed of the permanent magnets magnetized in multiple poles and the armature, and the input signal. A drive circuit that drives the motor, a rotation state detector that detects a state according to the rotation speed or rotation cycle of the motor, and an error signal for the target rotation speed or the target rotation cycle from the output of the rotation state detector Speed error detection circuit, a speed control circuit that outputs a torque signal so that an error signal of the speed error detection circuit becomes zero, a rotational position detector that detects a rotational position of the motor, and the rotational position detector An energization switching circuit that outputs an energization switching signal from the output of the energization switching circuit to the drive circuit and the energization combining circuit; an energization combining circuit that combines the output signals of the energization switching circuit; A torque pattern generation circuit that outputs a torque signal having a predetermined fluctuation pattern in synchronization with the output of the rotation state detector, a current detection circuit that detects a current flowing through the motor from the output of the drive circuit, and a current detection circuit of the current detection circuit. It is composed of a multiplication circuit that multiplies the output and the torque signal of the torque pattern generation circuit, and an addition circuit that adds the output of the speed control circuit and the output of the multiplication circuit and outputs the result to the drive circuit.

[0010]

According to the first configuration, when the motor load is constant, a pattern for canceling the torque ripple of the motor is first recorded in advance in the torque pattern generation circuit. By aligning the phase of the pattern with the phase of the torque ripple at the rise (or fall) of the energization signal and adding the torque pattern signal to the output signal of the conventional speed control circuit in synchronization with the output of the rotation state detector, It is possible to realize a motor speed control device that has no rotational unevenness due to ripples with a simple configuration.

Further, when the load of the motor changes according to the second configuration, the torque ripple is proportional to the current value. Therefore, a pattern in which the result of multiplication with the current value cancels the torque ripple is recorded in advance in the torque pattern generation circuit. The torque pattern generation circuit matches the phase of the pattern with the phase of the torque ripple at the rising (or falling) of the energization signal, and outputs the torque pattern signal in synchronization with the output of the rotation state detector. By adding the multiplication result of the torque pattern signal and the current value that changes according to the load to the output signal of the conventional speed control circuit, a motor speed control device that does not have rotational unevenness due to torque ripple that changes in proportion to the current is provided. It can be realized with a simple configuration.

[0012]

【Example】

(Embodiment 1) An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, reference numeral 1 designates a three-phase full-wave brushless motor consisting of a rotating permanent magnet with multi-pole magnetization and an armature.
2 is a rectangular wave drive circuit, 3 is a frequency generator, 4 is a speed error detection circuit, 5 is a speed control circuit, 6 is a position detector, 7 is a 120-degree energization switching circuit, 8 is an energization synthesis circuit, and 9 is torque. The pattern generation circuit 10 is an addition circuit.

The operation of the motor speed control device constructed as described above will be described with reference to FIG. First, the motor rotation cycle signal (or rotation speed signal) h detected by the frequency generator 3 is the speed error detection circuit 4
Is compared with the target rotation cycle (or target rotation speed signal) and an error signal is output. The speed control circuit 5 outputs a torque signal so that the error signal of the speed error detection circuit 4 becomes zero. On the other hand, the rotational position detector 6 detects the rotational position of the motor 1 and outputs a rotational position signal. The energization switching circuit outputs to the drive circuit 2 energization switching signals a to f for energizing each coil of the motor 1 according to the rotation position signal. The energization synthesizing circuit synthesizes the 120-degree energization switching signals a to f and outputs the energization signal g for each 60-degree energization angle. The torque pattern generation circuit 9 uses the energization signal g as a reference to generate a rotation cycle signal h.
Is input, a predetermined torque pattern signal i is sequentially input.
To the adder circuit 10. The adder circuit 10 adds the torque signal and the torque pattern signal i and outputs the result to the drive circuit 2. The drive circuit 2 outputs a drive current for driving the motor 1 to the motor 1 according to the torque signal, and the motor 1 produces a torque ripple proportional to the magnitude of the torque and the drive current at a conduction angle of 60 degrees. Occurs as a cycle. At this time, the torque ripple of the motor 1 is canceled by setting the pattern of the torque pattern generation circuit 7 so as to cancel the torque ripple, and only the torque signal of the speed control circuit 5 is generated as the torque j of the motor 1. As is apparent from this, the motor speed control device according to the present embodiment has an effect that torque ripple does not affect speed control.

As described above, according to this embodiment, the torque pattern signal of the torque pattern generating circuit 9 and the torque signal of the speed control circuit 5 are added to eliminate the rotational irregularity due to the torque ripple generated by the motor 1. You can

(Second Embodiment) A second embodiment of the present invention will be described below with reference to the drawings.

In FIG. 3, reference numeral 1 denotes a three-phase full-wave brushless motor consisting of a rotating permanent magnet with multi-pole magnetization and an armature.
2 is a rectangular wave drive circuit, 3 is a frequency generator, 4 is a speed error detection circuit, 5 is a speed control circuit, 6 is a position detector, 7 is a 120-degree energization switching circuit, 8 is an energization synthesis circuit, and 9 is torque. A pattern generation circuit, 10 is an addition circuit, 11 is a current detection circuit, and 12 is a multiplication circuit.

The operation of the motor speed control device configured as described above will be described with reference to FIG. First, the motor rotation cycle signal (or rotation speed signal) h detected by the frequency generator 3 is the speed error detection circuit 4
Is compared with the target rotation cycle (or target rotation speed signal) and an error signal is output. The speed control circuit 5 outputs a torque signal so that the error signal of the speed error detection circuit 4 becomes zero. On the other hand, the rotational position detector 6 detects the rotational position of the motor 1 and outputs a rotational position signal. The energization switching circuit outputs to the drive circuit 2 energization switching signals a to f for energizing each coil of the motor 1 according to the rotation position signal. The energization synthesizing circuit synthesizes the 120-degree energization switching signals a to f and outputs the energization signal g for each 60-degree energization angle. The torque pattern generation circuit 9 uses the energization signal g as a reference to generate a rotation cycle signal h.
Is input, a predetermined torque pattern signal i is sequentially input.
Is output to the multiplication circuit 12. The current detection circuit 11 detects the current supplied to the motor by the drive circuit 2 and outputs a current signal to the multiplication circuit 12. The multiplication circuit 12 multiplies the torque pattern signal i and the current signal and outputs the multiplied torque pattern signal to the addition circuit 10. The adder circuit 10 adds the multiplied torque pattern signal and the torque signal and outputs the result to the drive circuit 2. The drive circuit 2 outputs a drive current for driving the motor 1 to the motor 1 according to the torque signal, and the motor 1 produces a torque ripple proportional to the magnitude of the torque and the drive current at a conduction angle of 60 degrees. Occurs as a cycle. At this time, the torque ripple of the motor 1 is canceled by setting the pattern of the torque pattern generation circuit 9 to cancel the torque ripple, and the torque ripple is canceled according to the drive current even if the load applied to the motor 1 changes. Since the torque changes as described above, only the torque signal of the speed control circuit 5 is generated as the torque j of the motor 1. As is apparent from this, the motor speed control device according to the present embodiment is
The effect that there is no influence on the speed control due to the torque ripple is obtained.

As described above, according to this embodiment, the multiplication torque pattern signal output by the multiplication circuit 12 for multiplying the torque pattern signal of the torque pattern generation circuit 9 by the output of the current detection circuit and the torque signal of the speed control circuit 5. By adding, it is possible to eliminate the rotational unevenness due to the torque ripple generated in proportion to the current of the motor 1.

In the first and second embodiments, the outputs of the energization switching circuit and the energization synthesizing circuit are set every 60 degrees.
The pattern of the torque pattern circuit may be an integral multiple of 60 degrees and may be a similar multiple. In the second embodiment, the current detection circuit 11 detects the current from the drive circuit 2, but
The current detection circuit 11 may detect the current from the torque signal of the speed control circuit 5.

[0021]

As described above, according to the present invention, when the motor load is constant, the motor speed control device is provided with the energization synthesizing circuit, the pattern generating circuit, and the adding circuit, and when the load changes, the motor speed control is performed. By providing an energization synthesizing circuit, a pattern generating circuit, a current detecting circuit, a multiplying circuit, and an adding circuit in the device, it is possible to realize an excellent motor speed control device that does not have uneven rotation caused by torque ripple.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a motor speed control device according to a first embodiment of the present invention.

FIG. 2 is a time chart for explaining the operation of the motor speed control device according to the first embodiment of the present invention.

FIG. 3 is a block diagram showing a configuration of a motor speed control device according to a second embodiment of the present invention.

FIG. 4 is a block diagram showing a configuration of a conventional motor speed control device.

[Explanation of symbols]

 1 Motor 2 Drive Circuit 3 Frequency Generator 4 Speed Error Detection Circuit 5 Speed Control Circuit 6 Position Detector 7 Energization Switching Circuit 8 Energization Synthesis Circuit 9 Torque Pattern Generation Circuit 10 Addition Circuit 11 Current Detection Circuit 12 Multiplication Circuits a, b, c , D, e, f energization signal g energization synthesis signal h rotation period signal i torque pattern signal j torque

[Procedure amendment]

[Submission date] February 15, 1995

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0020

[Correction method] Change

[Correction content]

In the first and second embodiments, the outputs of the energization switching circuit and the energization synthesizing circuit are set every 60 degrees.
The pattern of the torque pattern circuit may be an integral multiple of 60 degrees and may be a similar multiple. Although the current detection circuit 11 detects the current from the drive circuit 2 in the second embodiment,
The current detection circuit 11 may detect the current from the torque control of the speed control circuit 5. Also, in each of the above examples
Speed error detection circuit 4, speed control circuit 5, torque pattern
The time generation circuit 9, the adder circuit 10, and the multiplier circuit 12 manage time.
Processing by a computer system capable of
It can also be realized by the above, and is not limited to the embodiment.

Claims (2)

[Claims] 1. A motor comprising a multi-pole magnetized permanent magnet and an armature, a drive circuit for driving the motor according to an input signal, and a state corresponding to the rotation speed or rotation cycle of the motor is detected. A rotation state detector, a speed error detection circuit that outputs an error signal for the target rotation speed or the target rotation cycle from the output of the rotation state detector, and a torque signal that makes the error signal of the speed error detection circuit zero. A speed control circuit for outputting, a rotational position detector for detecting a rotational position of the motor, an energization switching circuit for outputting an energization switching signal from the output of the rotational position detector to the drive circuit and the energization combining circuit, and the energization An energization composing circuit for composing the output signals of the switching circuit, and a torque signal of a predetermined fluctuation pattern in synchronization with the outputs of the energization composing circuit and the rotation state detector Of the motor having a torque pattern generation circuit that outputs only the least common multiple of the permanent magnets and the armature of the motor, and an addition circuit that adds the output of the speed control circuit and the output of the torque pattern generator to the drive circuit. Control device. 2. A motor composed of a multi-pole magnetized permanent magnet and an armature, a drive circuit for driving the motor in response to an input signal, and a state corresponding to the rotation speed or rotation cycle of the motor is detected. A rotation state detector, a speed error detection circuit that outputs an error signal for the target rotation speed or the target rotation cycle from the output of the rotation state detector, and a torque signal that makes the error signal of the speed error detection circuit zero. A speed control circuit for outputting, a rotational position detector for detecting a rotational position of the motor, an energization switching circuit for outputting an energization switching signal from the output of the rotational position detector to the drive circuit and the energization switching circuit, and the energization An energization synthesizing circuit for synthesizing the output signals of the switching circuit and a torque signal having a predetermined fluctuation pattern are synchronized with the outputs of the energization synthesizing circuit and the rotation state detector. A torque pattern generation circuit that outputs only the least common multiple of permanent magnets and armatures of the motor, a current detection circuit that detects a current flowing from the drive circuit to the motor and outputs a signal proportional to the current, and an output of the current detection circuit Speed of the motor including a multiplication circuit that multiplies the output signal of the torque pattern generation circuit and the output signal of the torque pattern generation circuit and an addition circuit that adds the output of the speed control circuit and the output of the multiplication circuit to the drive circuit. Control device.