WO2013105239A1

WO2013105239A1 - Motor rotational direction detection method, and motor drive circuit

Info

Publication number: WO2013105239A1
Application number: PCT/JP2012/050408
Authority: WO
Inventors: 智生原田
Original assignee: 新電元工業株式会社
Priority date: 2012-01-11
Filing date: 2012-01-11
Publication date: 2013-07-18

Abstract

[Problem] To provide a motor rotational direction detection method whereby it is possible to detect the rotational direction of a rotor by only using two hall elements. [Solution] A motor rotational direction detection method detects the rotational direction of a brushless motor by only using a first hall element for detecting the magnetic pole of the first phase of a rotor and a second hall element for detecting the magnetic pole of the second phase of the rotor, wherein it is determined that the rotor is rotating in a first rotational direction when the level of a second pulse signal outputted from the second hall element in accordance with the rotation of the rotor of the brushless motor is at a first level at the first edge of a first pulse signal outputted from the first hall element in accordance with the rotation of the rotor of the brushless motor, and it is determined that the rotor is rotating in a second rotational direction which is in the opposite direction from the first rotational direction when the level of the second signal is at a second level at the first edge of the first pulse signal.

Description

Motor rotation direction detection method and motor drive circuit

The present invention relates to a motor rotation direction detection method and a motor drive circuit.

Conventionally, for example, in the motor rotation direction detection method described in JP2008-14287A, a U-phase Hall element H2 that detects a U-phase magnetic pole of the rotor R, a V-phase Hall element H3 that detects a V-phase magnetic pole of the rotor R, and The rotation direction of the brushless motor M is detected by using three hall elements of the W-phase hall element H1 for detecting the W-phase magnetic pole of the rotor R (FIG. 5).

This conventional motor rotation direction detection method is based on the change of the rotational position of the rotor R based on the levels (“Hi” level or “Lo” level) of the three pulse signals output by the three Hall elements H1 to H3. That is, changes in the rotor states S1 to S6 are detected (FIG. 6).

From the above operation, in the conventional motor rotation direction detection method, it is determined whether the rotor R is rotating forward or reverse (FIG. 7).

This conventional method for detecting the rotational direction of the motor uses three expensive Hall elements H1 to H3 and also requires harnesses and terminals to be connected to these Hall elements, which increases the production cost of the system.

Furthermore, in order to output a detection signal with higher accuracy, the positioning accuracy of the Hall elements is required, and there is a problem that the yield of the product decreases as the number of Hall elements increases.

Further, in the conventional motor rotation direction detection method, it is necessary to detect at least two states of the rotor R (for example, the rotor states S1 and S2), and there is a problem that it is difficult to construct a system for performing the above operation. is there.

A motor rotation direction detection method according to an embodiment of one aspect of the present invention includes:
A motor rotation detection method for detecting the rotation direction of a brushless motor using only a first Hall element for detecting the magnetic pole of the first phase of the rotor and a second Hall element for detecting the magnetic pole of the second phase of the rotor. Because
At the first edge of the first pulse signal output by the first Hall element in response to rotation of the rotor of the brushless motor, the second Hall element is output in response to rotation of the rotor of the brushless motor. When the level of the second pulse signal is the first level, it is determined that the rotor is rotating in the first rotation direction;
On the other hand, when the level of the second pulse signal is the second level at the first edge of the first pulse signal, the rotor rotates in the second rotation direction opposite to the first rotation direction. It is characterized in that it is rotating.

In the motor rotation direction detection method,
The first edge of the first pulse signal is a rising edge, the first level is a “Hi” level, and the second level is a “Lo” level. Good.

In the motor rotation direction detection method,
The first edge of the first pulse signal is a falling edge, the first level is a “Lo” level, and the second level is a “Hi” level. Also good.

In the motor rotation direction detection method,
The brushless motor may be a three-phase braless motor.

A motor drive circuit according to an embodiment according to one aspect of the present invention includes:
A motor drive circuit for detecting the rotation direction of a brushless motor using only a first Hall element for detecting the magnetic pole of the first phase of the rotor and a second Hall element for detecting the magnetic pole of the second phase of the rotor. There,
A motor driver for supplying a driving current to the brushless motor to drive the brushless motor;
Control for detecting the rotation direction of the brushless motor and controlling the motor driver based on pulse signals output from the first Hall element and the second Hall element in accordance with rotation of the rotor of the brushless motor. A circuit,
The control circuit includes:
When the level of the second pulse signal output from the second Hall element is the first level at the first edge of the first pulse signal output from the first Hall element, the rotor is Judge that it is rotating in the first rotation direction,
On the other hand, when the level of the second pulse signal is the second level at the first edge of the first pulse signal, the rotor rotates in the second rotation direction opposite to the first rotation direction. It is characterized in that it is rotating.

In the motor drive circuit,
The first Hall element and the second Hall element are arranged in the order of the first Hall element and the second Hall element in the first rotation direction of the rotor, in proximity to the rotor. You may do it.

In the motor drive circuit,
The first edge of the first pulse signal is a rising edge, the first level is a “Hi” level, and the second level is a “Lo” level. Good.

In the motor drive circuit,
The first edge of the first pulse signal is a falling edge, the first level is a “Lo” level, and the second level is a “Hi” level. Also good.

In the motor drive circuit,
The control circuit may control the motor driver based on the detected rotation direction of the rotor.

In the motor drive circuit,
The first rotation direction may be a normal rotation direction of the rotor, and the second rotation direction may be a reverse rotation direction of the rotor.

In the motor drive circuit,
The control circuit may output a signal corresponding to the detected rotation direction of the rotor to the outside.

In the motor drive circuit,
You may make it provide the 1st pulse signal input terminal into which the said 1st pulse signal is input, and the 2nd pulse signal input terminal into which the said 2nd pulse signal is input.

In the motor drive circuit,
The first Hall element and the second Hall element may be disposed inside a stator of the brushless motor or an exterior of the brushless motor.

In the motor drive circuit,
The brushless motor may be a three-phase braless motor.

In the motor drive circuit,
The magnetic pole of the first phase is a W-phase magnetic pole, the magnetic pole of the second phase is a U-phase magnetic pole, the first Hall element is a W-phase Hall element, and the second hole The element may be a W-phase Hall element.

In the motor rotation direction detection method according to one aspect of the present invention, only the first Hall element that detects the magnetic pole of the first phase of the rotor and the second Hall element that detects the magnetic pole of the second phase of the rotor are used. To detect the direction of rotation of the brushless motor.

In this motor rotation direction detection method, at the first edge (for example, the rising edge) of the first pulse signal output from the first Hall element according to the rotation of the brushless motor rotor, the rotation of the brushless motor rotor is detected. Accordingly, when the level of the second pulse signal output from the second Hall element is the first level (for example, “Hi” level), the rotor rotates in the first rotation direction (forward rotation direction). Judge that

In this motor rotation direction detection method, when the level of the second pulse signal is the second level (for example, “Lo” level) at the first edge (for example, the rising edge) of the first pulse signal. Determines that the rotor is rotating in the second rotation direction (reverse rotation direction) opposite to the first rotation direction.

Thereby, the motor rotation direction detection method according to one aspect of the present invention can detect the rotation direction of the rotor while reducing the number of Hall elements as compared with the conventional one.

Therefore, it is possible to reduce expensive hall elements, harnesses and terminals to be connected to the hall elements.

Furthermore, the yield of products can be improved by reducing the number of Hall elements. Thereby, for example, the manufacturing cost of the cell die system to which the motor rotation direction detection method and the motor drive circuit of the present invention are applied can be reduced.

In particular, the motor rotation direction detection method according to one aspect of the present invention can determine the rotation direction of the rotor by determining one state of the rotor. For this reason, it is easy to construct a system that executes this motor rotation direction detection method.

FIG. 1 is a diagram illustrating an example of a configuration of a motor drive system according to a first embodiment which is an aspect of the present invention. FIG. 2 is a diagram illustrating an example of the configuration of the brushless motor illustrated in FIG. 1. FIG. 3 is a diagram showing the relationship between the waveforms of the first and second pulse signals shown in FIG. 1 and the rotation direction of the rotor R. FIG. 4 is a diagram showing the relationship between the edge of the first pulse signal and the level of the second pulse signal, and the rotation direction of the rotor R. FIG. 5 is a diagram showing an example of the configuration of a conventional brushless motor. FIG. 6 is a diagram showing the relationship between the waveform of the pulse signal output from the conventional Hall element and the rotation direction of the rotor R. FIG. 7 is a diagram showing the relationship between the level of the pulse signal output from the conventional Hall element and the rotation direction of the rotor R.

Hereinafter, each embodiment according to the present invention will be described with reference to the drawings.

In the embodiment, the case where the brushless motor M is a three-phase braless motor will be described as an example. In particular, the first phase magnetic pole is a W phase magnetic pole, the second phase magnetic pole is a U phase magnetic pole, the first Hall element H1 is a W phase Hall element, and the second Hall element is A case where H2 is a W-phase Hall element will be described. However, the first-phase magnetic pole is a V-phase magnetic pole, the second-phase magnetic pole is a W-phase magnetic pole, the first Hall element H1 is a V-phase Hall element, and the second Hall element is H2 is described in the same manner even in other combinations, such as in the case of a W-phase Hall element.

FIG. 1 is a diagram illustrating an example of a configuration of a motor drive system 100 according to a first embodiment which is an aspect of the present invention. FIG. 2 is a diagram showing an example of the configuration of the brushless motor M shown in FIG.

As shown in FIG. 1, a motor drive system 100 includes a brushless motor (three-phase braless motor) M, a motor drive circuit 1, and a first hall element (W-phase hall element) H1 provided in the brushless motor M. And a second Hall element (U-phase Hall element) H2 provided in the brushless motor M.

That is, the motor drive system 100 includes only two Hall elements for the three-phase brushless motor.

Here, as shown in FIG. 2, the brushless motor M includes a first winding (W-phase winding) W1, a second winding (U-phase winding) W2, and a third winding (V-phase winding). Line) It has the stator St provided with W3, and the rotor R.

The first Hall element H1 and the second Hall element H2 are disposed inside the exterior of the brushless motor M. However, the first Hall element H1 and the second Hall element H2 may be disposed on the stator St.

In particular, the first Hall element H1 and the second Hall element H2 are, for example, close to the rotor R in the first rotation direction (forward rotation direction) of the rotor R. The Hall elements H2 are arranged in this order (FIG. 2).

Then, the motor drive circuit 1 detects the first Hall element H1 that detects the first phase (W phase) magnetic pole of the rotor R and the second phase that detects the second phase (U phase) magnetic pole of the rotor R. The rotation direction of the brushless motor M is detected using only the hall element H2.

The motor drive circuit 1 includes a first pulse signal input terminal TP1 to which a first pulse signal P1 output from the first Hall element H1 is input according to the rotation of the rotor R of the brushless motor M, and the brushless motor M. And a second pulse signal input terminal TP2 to which a second pulse signal P2 output from the second Hall element H2 is input according to the rotation of the rotor R.

Furthermore, the motor drive circuit 1 includes a motor driver D and a control circuit CON.

The motor driver D supplies a drive current to the brushless motor M to drive the brushless motor M.

The control circuit CON controls the brushless motor M based on the first and second pulse signals P1 and P2 output from the first Hall element H1 and the second Hall element H2 according to the rotation of the rotor R of the brushless motor M. Is detected, and the motor driver D is controlled.

For example, the control circuit CON outputs the second pulse output from the second Hall element H2 at the first edge (for example, the falling edge) of the first pulse signal P1 output from the first Hall element H1. When the level of the signal P2 is the first level (for example, “Hi” level), it is determined that the rotor R is rotating in the first rotation direction (for example, the forward rotation direction). .

In addition, the control circuit CON determines that the level of the second pulse signal P2 is the second level (for example, “Lo” level) at the first edge (for example, the falling edge) of the first pulse signal P1, for example. In this case, it is determined that the rotor R rotates in the second rotation direction (for example, the reverse direction) opposite to the first rotation direction.

The control circuit CON controls the motor driver D based on the detected rotation direction of the rotor R.

Further, the control circuit CON outputs a signal according to the detected rotation direction of the rotor R to the outside.

Here, an example of a motor rotation detection method by the motor drive circuit 1 having the above configuration will be described.

FIG. 3 is a diagram showing the relationship between the waveforms of the first and second pulse signals P1 and P2 shown in FIG. FIG. 4 is a diagram illustrating the relationship between the edge of the first pulse signal P1 and the level of the second pulse signal P2, and the rotation direction of the rotor R.

For example, as shown in FIG. 3, the first edge (for example, the falling edge) of the first pulse signal P1 is set as the determination timing.

In this case, the control circuit CON sets the brushless motor at the first edge (for example, the falling edge) of the first pulse signal P1 output from the first Hall element H1 according to the rotation of the rotor R of the brushless motor M. When the level of the second pulse signal P2 output from the second Hall element H2 according to the rotation of the M rotor R is the first level ("Hi" level), the rotor R is in the first rotational direction. It is determined that the motor is rotating in the (forward direction) (FIG. 4).

On the other hand, when the level of the second pulse signal P2 is the second level (“Lo” level) at the first edge (for example, the falling edge) of the first pulse signal P1, the control circuit CON It is determined that the rotor R is rotating in the second rotation direction (reverse rotation direction) (FIG. 4).

Further, as shown in FIG. 3, the second edge (for example, the rising edge) of the first pulse signal P1 may be used as the determination timing.

In this case, the control circuit CON controls the brushless motor M at the second edge (for example, the rising edge) of the first pulse signal P1 output from the first Hall element H1 according to the rotation of the rotor R of the brushless motor M. When the level of the second pulse signal P2 output from the second Hall element H2 in response to the rotation of the rotor R is the second level ("Lo" level), the rotor R moves in the first rotational direction ( It is determined that the motor rotates in the forward direction (FIG. 4).

On the other hand, when the level of the second pulse signal P2 is the first level (“Hi” level) at the second edge (for example, the rising edge) of the first pulse signal P1, the control circuit CON It is determined that R is rotating in the second rotation direction (reverse rotation direction) (FIG. 4).

As described above, in the motor rotation direction detection method according to one aspect of the present invention, the first Hall element H1 that detects the magnetic pole of the first phase (for example, W phase) of the rotor R and the second of the rotor R are detected. The rotation direction of the brushless motor M is detected using only the second Hall element H2 that detects the magnetic pole of the phase (for example, the U phase).

In this motor rotation direction detection method, at the first edge (for example, the rising edge) of the first pulse signal P1 output from the first Hall element H1 according to the rotation of the rotor R of the brushless motor M, the brushless motor M is detected. When the level of the second pulse signal P2 output from the second Hall element H2 in response to the rotation of the rotor R is the first level (for example, “Hi” level), the rotor R is rotated in the first rotation. Judged to be rotating in the direction (forward direction).

In this motor rotation direction detection method, when the level of the second pulse signal is the second level (for example, “Lo” level) at the first edge (for example, the rising edge) of the first pulse signal. Determines that the rotor R is rotating in the second rotation direction (reverse rotation direction) opposite to the first rotation direction.

Thereby, the motor rotation direction detection method according to one aspect of the present invention can detect the rotation direction of the rotor R while reducing the number of Hall elements as compared with the conventional method.

Therefore, it is possible to reduce expensive hall elements, harnesses to be connected to the hall elements, and terminals TP1 and TP2.

In particular, the motor rotation direction detection method according to one aspect of the present invention can determine the rotation direction of the rotor R if one state of the rotor R is determined. For this reason, it is easy to construct a system that executes this motor rotation direction detection method.

In the embodiment described above, the first edge of the first pulse signal P1 is the rising edge, the first level is the “Hi” level, and the second level is the “Lo” level. The case where

However, the same applies to the case where the first edge of the first pulse signal P1 is a falling edge, the first level is the “Lo” level, and the second level is the “Hi” level. An effect can be produced.

In addition, embodiment is an illustration and the range of invention is not limited to them.

100 Motor drive system M Brushless motor (3-phase braless motor)
1 Motor drive circuit H1 First Hall element (W-phase Hall element)
H2 Second Hall element (U-phase Hall element)
H3 Third Hall element (V-phase Hall element)
P1 First pulse signal P2 Second pulse signal TP1 First pulse signal input terminal TP2 Second pulse signal input terminal W1 First winding (W-phase winding)
W2 Second winding (U-phase winding)
W3 3rd winding (V phase winding)
R Rotor St Stator

Claims

A motor rotation detection method for detecting the rotation direction of a brushless motor using only a first Hall element for detecting the magnetic pole of the first phase of the rotor and a second Hall element for detecting the magnetic pole of the second phase of the rotor. Because
At the first edge of the first pulse signal output by the first Hall element in response to rotation of the rotor of the brushless motor, the second Hall element is output in response to rotation of the rotor of the brushless motor. When the level of the second pulse signal is the first level, it is determined that the rotor is rotating in the first rotation direction;
On the other hand, when the level of the second pulse signal is the second level at the first edge of the first pulse signal, the rotor rotates in the second rotation direction opposite to the first rotation direction. A method for detecting the direction of motor rotation, characterized in that it is determined that the motor is rotating.
The first edge of the first pulse signal is a rising edge, the first level is a “Hi” level, and the second level is a “Lo” level. The motor rotation direction detection method according to claim 1.
The first edge of the first pulse signal is a falling edge, the first level is a “Lo” level, and the second level is a “Hi” level. The motor rotation direction detection method according to claim 1.
The motor rotation direction detection method according to any one of claims 1 to 3, wherein the brushless motor is a three-phase braless motor.
A motor drive circuit that detects the rotation direction of a brushless motor using only a first Hall element that detects the magnetic pole of the first phase of the rotor and a second Hall element that detects the magnetic pole of the second phase of the rotor. There,
A motor driver for supplying a driving current to the brushless motor to drive the brushless motor;
Control for detecting the rotation direction of the brushless motor and controlling the motor driver based on pulse signals output from the first Hall element and the second Hall element in accordance with the rotation of the rotor of the brushless motor. A circuit,
The control circuit includes:
When the level of the second pulse signal output from the second Hall element is the first level at the first edge of the first pulse signal output from the first Hall element, the rotor is Judge that it is rotating in the first rotation direction,
On the other hand, when the level of the second pulse signal is the second level at the first edge of the first pulse signal, the rotor rotates in the second rotational direction opposite to the first rotational direction. A motor drive circuit characterized by determining that the motor is rotating.
The first Hall element and the second Hall element are arranged in the order of the first Hall element and the second Hall element in the first rotation direction of the rotor, in proximity to the rotor. 6. The motor drive circuit according to claim 5, wherein
The first edge of the first pulse signal is a rising edge, the first level is a “Hi” level, and the second level is a “Lo” level. The motor drive circuit according to claim 5 or 6.
The first edge of the first pulse signal is a falling edge, the first level is a “Lo” level, and the second level is a “Hi” level. The motor drive circuit according to claim 5 or 6.
9. The motor drive circuit according to claim 5, wherein the control circuit controls the motor driver based on the detected rotation direction of the rotor.
The first rotation direction is a forward rotation direction of the rotor, and the second rotation direction is a reverse rotation direction of the rotor. Motor drive circuit.
11. The motor drive circuit according to claim 5, wherein the control circuit outputs a signal according to the detected rotation direction of the rotor to the outside.
12. A first pulse signal input terminal to which the first pulse signal is input, and a second pulse signal input terminal to which the second pulse signal is input. The motor drive circuit according to any one of the above.
13. The first Hall element and the second Hall element are arranged inside a stator of the brushless motor or an exterior of the brushless motor, according to any one of claims 5 to 12. Motor drive circuit.
14. The motor drive circuit according to claim 5, wherein the brushless motor is a three-phase braless motor.
The magnetic pole of the first phase is a W-phase magnetic pole, the magnetic pole of the second phase is a U-phase magnetic pole, the first Hall element is a W-phase Hall element, and the second hole 15. The motor driving circuit according to claim 5, wherein the element is a W-phase Hall element.