JP2000270580A - Motor controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize controlling of exciting voltages for the respective phases of a 3-phase motor based on detection positions with a small number of sensors. SOLUTION: In a 3-phase SR motor which has a stator comprising symmetrical 3-phase (phase-U, phase-V and phase-W) windings and a rotor with four protrusions, sensors which detect the positions of the phase-U and phase-V only are provided. The sensors output detection signals having pulse widths of 30 degrees with a period of 90 degrees. The application of an excitation voltage to the phase-U or phase-V is controlled with the rise of the corresponding detection signal as a reference and the application of an exciting voltage to the phase-W is controlled with the rise of the detection signal of the phase-U.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor control device, and more particularly, to a motor configured to detect a relative position between each of multi-phase windings and a rotor and to sequentially apply an excitation voltage to each phase. Related to a control device.

[0002]

2. Description of the Related Art In recent years, the use of an SR (switched reluctance) motor or the like has been studied as a motor used to drive an oil pump or the like used in an automobile power steering device.

[0003] The present applicant has proposed that the SR motor 3
3 for detecting the position of each phase (U phase, V phase, W phase)
A motor control device having two position sensors and configured to control the application of the excitation voltage to each phase using the detection signal from each position sensor as a reference position has been previously proposed (Japanese Patent Application No. 10-3).
05605, Japanese Patent Application No. 10-305606).

[0004]

However, the above configuration has a problem that it is disadvantageous in cost because three position sensors are required for each phase.

The present invention has been made in view of the above problems, and provides a motor control device capable of sequentially applying an excitation voltage in accordance with the position of each phase without providing position sensors for all phases. The purpose is to do.

[0006]

According to a first aspect of the present invention, there is provided a motor control device having a multi-phase winding, wherein a position sensor for detecting a relative position between the winding and the rotor is partially provided. The control of the application of the excitation voltage to the winding of the phase provided with the position sensor is performed based on the detection signal from the corresponding position sensor, while the excitation of the winding of the phase not provided with the position sensor is provided. The voltage application is controlled based on a detection signal from a position sensor corresponding to another phase.

According to this configuration, the position sensor is not provided in all the phases, but is provided in only some of the phases. In the phase in which the position sensor is provided, the excitation voltage is determined based on the detection signal of the sensor. Is controlled,
In the phase where the position sensor is omitted, the application of the excitation voltage is controlled on the basis of the detection signal which originally corresponds to another phase.

In the invention according to claim 2, the multi-phase winding is a symmetric three-phase winding, and four projections are arranged on the rotor at equal intervals in a circumferential direction, and among the three phases, The position sensor is provided for each of the two phases, and each of the position sensors outputs a detection signal having a pulse width of 30 degrees at a cycle of 90 degrees. While the application of the excitation voltage is controlled on the basis of the fall of the detection signal, the application of the excitation voltage to the winding of the phase where the position sensor is not provided is controlled on the basis of the rise of the detection signal of the next phase. .

According to this configuration, if a position sensor is provided only in the U-phase and the V-phase among the three phases of the U-phase, the V-phase and the W-phase, the detection signal corresponding to the U-phase is a 30-degree pulse. When the detection signal corresponding to the V phase is output, the detection signal corresponding to the V phase is also output with the pulse width of 30 degrees, and the detection signal of the W phase should be output. Does not output the detection signal.

Here, for the U-phase and the V-phase, the application of the excitation voltage is controlled based on the fall of the detection signal corresponding to each phase, but since there is no detection signal corresponding to the W-phase, Although the application of the excitation voltage cannot be controlled similarly to the U-phase and the V-phase, if a position sensor is also provided for the W-phase, the fall of the detection signal corresponding to the W-phase is V In order to synchronize with the rise of the phase detection signal, if the application of the excitation voltage is controlled based on the rise of the V-phase detection signal, control is eventually performed based on the fall of the detection signal corresponding to the W-phase. It will be the same as the case.

According to a third aspect of the present invention, there is provided a motor control device including a multi-phase winding, wherein a position sensor for detecting a relative position between the winding and the rotor is provided only for some of the phases. Controlling the application of the excitation voltage to the winding of the phase provided with the position sensor based on the detection signal from the corresponding position sensor, and the detection signal to the winding of the phase not provided with the position sensor. A pseudo signal is generated based on a detection signal corresponding to a phase, and application of an excitation voltage to a winding of a phase in which the position sensor is not provided is controlled based on the pseudo detection signal.

According to this configuration, a detection signal corresponding to a phase not having a position sensor is pseudo-generated from a detection signal corresponding to another phase.
The application of the excitation voltage is controlled by the same control based on the corresponding detection signal.

[0013] In the invention described in claim 4, the multi-phase winding is a symmetric three-phase winding, and four projections are arranged on the rotor at equal intervals in the circumferential direction. The position sensor is provided for each of the two phases, and each of the position sensors outputs a detection signal having a pulse width of 30 degrees at a cycle of 90 degrees, and outputs a pseudo detection signal corresponding to the remaining one phase. It is configured to be turned on between the two-phase detection signals and generated.

According to this configuration, if a position sensor is provided only in the U-phase and the V-phase among the three phases of the U-phase, the V-phase and the W-phase, for example, the detection signal corresponding to the U-phase is a 30-degree pulse. When the detection signal corresponding to the V phase is output, the detection signal corresponding to the V phase is also output with the pulse width of 30 degrees, and the detection signal of the W phase should be output. Does not output the detection signal. Therefore, a signal that is turned on during 30 degrees when the detection signal is not output from any of the sensors is generated, and is used as a W-phase pseudo detection signal as a reference in controlling the application of the excitation voltage to the W-phase.

According to the fifth aspect of the present invention, the application of the excitation voltage to the winding of the corresponding phase is controlled based on the fall of the detection signal or the pseudo detection signal.
According to such a configuration, for example, based on the time measurement based on the fall of the detection signal (including the pseudo detection signal) corresponding to each phase, the ON timing and the OFF timing of the excitation voltage for each phase are detected, Apply the excitation voltage.

[0016]

According to the first aspect of the present invention, the application of the excitation voltage is controlled on the basis of the detection signals corresponding to the other phases with respect to the phase having no position sensor. Even if it is not provided, there is an effect that the excitation voltage can be sequentially applied to each phase.

According to a second aspect of the present invention, in a motor having three-phase windings, when the application of the excitation voltage is controlled based on the fall of the detection signal from the position sensor, the position sensor For phases without
There is an effect that the application of the excitation voltage can be controlled based on the same timing as the other phases.

According to the third aspect of the present invention, for a phase without a position sensor, a detection signal is pseudo-generated based on a detection signal corresponding to another phase. At least, there is an effect that the application of the excitation voltage can be controlled for all the phases based on the detection signals to be handled.

According to a fourth aspect of the present invention, in the motor having the three-phase winding, the pseudo detection signal corresponding to one phase without the position sensor is turned on at intervals of generation of the other two phase detection signals. And the application of the excitation voltage can be controlled with reference to the detection signals corresponding to each of the three phases.

According to the fifth aspect of the invention, there is an effect that the rotation of the motor can be controlled by controlling the timing of applying the excitation voltage to each phase by time measurement based on the fall of the detection signal or the pseudo detection signal. .

[0021]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a control system of a three-phase SR motor according to an embodiment of the present invention. The illustrated SR motor 1 is used as a power unit for driving an oil pump of a power steering device for an automobile. This will be described below. However, the invention is not limited to a motor for driving an oil pump.

FIG. 2 is a schematic diagram showing the internal structure of the SR motor 1, and FIG. 3 is a diagram showing a position sensor 3 for detecting a phase position of the SR motor 1. Hereinafter, the configurations of the SR motor 1 and the position sensor 3 will be described with reference to FIGS.

The SR motor 1 shown in FIG. 1 drives an oil pump 2 of a power steering device for an automobile to generate a steering assist force. Further, the SR motor 1
As shown in FIG. 2, it is configured to include a rotor 11 and a stator 12. The rotor 11 has four protrusions 13a to 13d arranged at equal intervals on the outer periphery thereof. On the other hand, the stator 12 has six coils 14u, 14v, and 14w arranged at equal intervals on the inner periphery thereof.

As shown in the figure, the coils are arranged at axially symmetric positions with the same reference numerals, and the six coils 14u, 14v, and 14w are symmetrical in three phases (U phase,
(V-phase, W-phase) coils (windings).

The SR motor 1 has the three phases (U phase, V phase).
Phase, W-phase) coil is rotated by sequentially applying an excitation voltage. SR motor 1 configured as described above
The control system includes a control unit 4 for controlling the application of the excitation voltage to each phase,
The position sensor 3 that outputs a detection signal to
It is composed of a steering angle sensor 5 and a vehicle speed sensor 6.

As shown in FIG. 3, the position sensor 3
It comprises a disk 31 and two optical sensors 32a and 32b. The disk 31 has a shaft connected to the rotor 11 and rotates integrally with the rotor 11. Further, the disk 31 is provided with four fan-shaped slits 33a to 33d for transmitting light at equal intervals on the same circumference. Each of the slits 33a to 33d is set to have a width such that the central angle is 30 degrees, and is disposed at a predetermined position corresponding to each of the protrusions 13a to 13d.

The optical sensor 32a is arranged on a line connecting a pair of U-phase coils, the optical sensor 32b is arranged on a line connecting a pair of V-phase coils, and the optical sensor 32a is positioned at a U-phase position. Sensor, optical sensor 32
b corresponds to a V-phase position sensor.

Each of the optical sensors 32a and 32b is composed of a light projecting unit and a light receiving unit which are arranged to face each other with the disk 31 interposed therebetween.
When the light passes through a to 33d and is received by the light receiving unit, a high level signal is output.

The slits 33a to 33d output the optical sensor 32 (detection signal) 30 degrees before the position where the U-phase or V-phase coil and the projections 13a to 13d are aligned on a straight line.
Rise, and the U-phase or V-phase coil and the projections 13a to 13
The optical sensor 32 is disposed at a position where the output of the optical sensor 32 falls when d and d are aligned. In other words, each of the slits 33a to 33d is connected to each of the projections 13a to 1d.
The detection signal corresponding to the U phase is a pulse signal having a width of 30 degrees that rises at a cycle of 90 degrees, and the detection signal corresponding to the V phase is: It becomes a pulse signal having a width of 30 degrees which rises in a 90-degree cycle and whose phase is delayed by 30 degrees from the detection signal corresponding to the U phase (see FIG. 5).

The control unit 4 controls to sequentially apply an excitation voltage to each phase based on output signals from the position sensor 3 (optical sensors 32a and 32b), the steering angle sensor 5 and the vehicle speed sensor 6. Execute.

Here, in the present embodiment, as described above,
The configuration includes only the optical sensors 32a and 32b for detecting the U phase and the V phase of the three phases (U phase, V phase, and W phase), and does not include a sensor that outputs a detection signal of the remaining W phase. Because of this configuration, even if an attempt is made to control the application of the excitation voltage for each phase based on the detection signal of each phase, the W phase cannot be controlled.

That is, the optical sensor 32 is set to 12
If three arrangements are arranged at 0 degree intervals, detection signals for each phase can be obtained as sensor outputs, respectively.
In this case, since three optical sensors 32 are required, the cost increases. Therefore, in the present embodiment, U
Although the optical sensors 32a and 32b for detecting the phase and the V phase are provided, the sensor for outputting the detection signal of the W phase is omitted, and the excitation voltage for the W phase is reduced as follows while reducing the sensor cost. Control can be performed in the same manner as the other phases.

The flowchart of FIG.
2 shows the control of the application of the excitation voltage to the U-phase and V-phase provided with reference numeral 2, and will be described with reference to the time chart of FIG.

The flowchart of FIG. 4 is started when the falling of the U-phase (V-phase) detection signal occurs. When the falling of the U-phase (V-phase) detection signal occurs, the counter timer is cleared. And start (S21).

In S22, it is determined whether or not a motor operation command is being generated. If an operation command is being generated, S
23, the time t1 from the fall of the U-phase (V-phase) detection signal to the start of the application of the excitation voltage to the U-phase (V-phase) coil is defined as the motor rotation speed, vehicle speed, and steering speed at that time. It is calculated and stored based on a comparison with a target rotation speed set based on an angle or the like.

At S24, if the excitation voltage is being output to the U-phase (V-phase) coil, the supply of the excitation voltage to the U-phase (V-phase) coil is interrupted. In S25, output / cutoff determination processing of the excitation voltage based on the elapsed time from the fall of the U-phase (V-phase) detection signal (hereinafter, referred to as compare match processing)
Set permissions for

In step S26, a state is set in which the output ON of the excitation voltage to the U-phase (V-phase) coil (hereinafter referred to as the compare match output ON) is permitted. In S27, it is determined whether or not the value of the counter timer has reached the time t1.

When the value of the counter timer reaches the time t1, the process proceeds to S28, and it is determined whether or not the compare match process is permitted. If so, the process proceeds to S29, where it is determined whether or not the compare match output ON is in a permitted state.

If the comparison match output ON is permitted, the process proceeds to S30, where the time t2 from the fall of the U-phase (V-phase) detection signal to the interruption of the excitation voltage to the U-phase (V-phase) coil is set. It is calculated and stored based on a comparison between the motor rotation speed at that time and a target rotation speed set based on the vehicle speed, the steering angle, and the like.

At S31, an excitation voltage to the U-phase (V-phase) coil is output. In S32, compare match output is ON
Is turned off, while the output of the excitation voltage to the U-phase (V-phase) coil is turned off (hereinafter, compare-match output is turned off).

In S33, it is determined whether or not the value of the counter timer has reached the time t2. When the value of the counter timer reaches the time t2, the process returns to S28. Here, since the compare match process is permitted, S29
The process proceeds from S29 to S34 because the compare match output ON is not permitted.

In S34, it is determined whether or not the comparison match output OFF is permitted, and the comparison match output O is determined.
Since the FF is permitted, the process proceeds to S35 and the U-phase (V
Phase) Turn OFF the output of the excitation voltage to the coil.

In S36, the compare match output OF
Disallow F. As described above, the application control of the excitation voltage to the U-phase and the V-phase provided with the optical sensor 32 is as follows.
The measurement is performed by time measurement based on the falling edges of the U-phase and V-phase detection signals. However, the W-phase without the optical sensor 32 cannot be controlled in the same manner as in the flowchart of FIG.

Therefore, for the W phase, as shown in the flowchart of FIG. 6, the application of the excitation voltage is controlled on the basis of the rise of the detection signal corresponding to the U phase. That is,
When the optical sensor 32 for the W phase is provided, the detection signal of the W phase rises at the fall of the detection signal corresponding to the V phase and the detection signal of the detection signal corresponding to the U phase as shown by a dotted line in FIG. Since the signal falls at the rise, the fall of the W-phase detection signal and the rise of the U-phase detection signal are synchronized, and the rise of the U-phase detection signal may be regarded as the fall of the W-phase detection signal. You can do it.

Therefore, even if the detection signal of the W-phase is not actually output, if the rising edge of the detection signal of the U-phase is set as the reference position of the voltage control for the W-phase, it is similar to the U-phase and the V-phase. The application of the excitation voltage is controlled on the basis of the fall of the corresponding detection signal.

The flowchart of FIG. 6 is the same as the flowchart of FIG. 4 except that the process is performed on the basis of the rise of the U-phase detection signal (except for S41), and the description of S42 and thereafter is omitted.

FIG. 7 is a flowchart showing the control of the application of the excitation voltage when the motor is started.
In step 1, it is determined whether there is a request for starting the motor. If there is no start request, the process proceeds to S62, in which application of the excitation voltage to the coils of each phase is cut off to stop the motor.

On the other hand, when an activation request is issued,
Proceeding to S63, it is determined whether or not the U-phase detection signal is ON. If the U-phase detection signal is ON, the process proceeds to S64, and the excitation voltage is first applied to the U-phase coil.

If the U-phase detection signal is OFF, S65
Then, it is determined whether or not the V-phase detection signal is ON. If the V-phase detection signal is ON, the process proceeds to S66,
First, an excitation voltage is applied to the V-phase coil.

If the V-phase detection signal is OFF, S67
Then, after confirming that both the U-phase and V-phase detection signals are OFF, the process proceeds to S68, where an excitation voltage is first applied to the W-phase coil.

By the way, in the above configuration, the application of the excitation voltage to the W-phase coil is controlled on the basis of the rise of the U-phase detection signal. And V-phase), the control can be performed based on the same timing as the reference. However, the detection signal of the W-phase is generated in a pseudo manner, and the excitation voltage of the W-phase is controlled based on the fall of the pseudo-detection signal. By doing so, voltage control can be performed with the same control specifications for all three phases.

The flowchart of FIG. 8 shows a process for generating a W-phase detection signal in a simulated manner.
It is determined whether the phase and V-phase detection signals are both in the OFF state.

When any of the above states is detected, S7
Proceed to 2 to turn on the W-phase pseudo detection signal. When the W-phase pseudo detection signal is turned ON, the process proceeds to S73, and it is determined whether or not the U-phase detection signal has risen. When the U-phase detection signal rises, the process proceeds to S74, in which the W-phase pseudo detection signal is turned off.

That is, when the W-phase optical sensor 32 is provided, the W-phase detection signal rises at the falling edge of the detection signal corresponding to the V-phase, and falls at the rising edge of the detection signal corresponding to the U-phase. Since the signal becomes a signal, it rises at the fall of the detection signal corresponding to the V phase, holds the ON state when both the U and V phase detection signals are OFF, and falls at the rise of the detection signal corresponding to the U phase. The signal is W
It is generated pseudo as a phase pseudo detection signal (see FIG. 9).

When the W-phase pseudo detection signal is generated as described above, the detection signals are output for all three phases. Therefore, the three-phase coil is determined based on the fall of the corresponding detection signal. It becomes possible to control the application of the excitation voltage to each.

That is, the control represented by the U-phase in the flow chart of FIG. 10 is similarly executed in the other phases (V-phase, W-phase), so that the excitation voltage for the three-phase coils is controlled. The application can be controlled.

In the flowchart of FIG.
By replacing the portion described as a phase with a V-phase or a W-phase, a control flow for the V-phase and a control flow for the W-phase are obtained. Since they are the same, detailed description is omitted.

[Brief description of the drawings]

FIG. 1 is a system diagram showing a control system of an SR motor according to an embodiment of the present invention.

FIG. 2 is a schematic diagram showing an internal structure of the SR motor.

FIG. 3 is a diagram showing a configuration of a position sensor according to the embodiment.

FIG. 4 is a flowchart illustrating control of an excitation voltage for U-phase and V-phase coils according to the first embodiment;

FIG. 5 is a time chart showing a correlation between a detection signal and an output of an excitation voltage in the first embodiment.

FIG. 6 is a flowchart showing control of an excitation voltage for a W-phase coil in the first embodiment.

FIG. 7 is a flowchart showing control at the time of startup in the first embodiment.

FIG. 8 is a flowchart illustrating generation of a W-phase pseudo detection signal according to the second embodiment.

FIG. 9 is a time chart showing a correlation between a detection signal and an output of an excitation voltage in the second embodiment.

FIG. 10 is a flowchart illustrating control of an excitation voltage common to U-phase, V-phase, and W-phase in the second embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... SR motor 2 ... Oil pump 3 ... Position sensor 4 ... Control unit 5 ... Steering angle sensor 6 ... Vehicle speed sensor 11 ... Rotor 12 ... Stator 13a-13d ... Projection 14u, 14v, 14w ... Coil 31 ... Disk 32a, 32b ... Optical sensors 33a to 33d ... Slit

Claims (5)

[Claims] 1. A motor control device comprising a multi-phase winding, comprising: a position sensor for detecting a relative position between a winding and a rotor for only some of the phases; The application of the excitation voltage to the windings of the phase is controlled based on the detection signal from the corresponding position sensor, while the application of the excitation voltage to the windings of the phase in which the position sensor is not provided is controlled by the position sensors corresponding to the other phases. A motor control device characterized in that control is performed based on a detection signal from the motor. 2. The multi-phase winding is a symmetric three-phase winding,
While four protrusions are arranged on the rotor at equal intervals in the circumferential direction, the position sensors are provided in each of two phases of the three phases, and each of the position sensors has a 90-degree cycle of 30 degrees. This configuration outputs a pulse width detection signal, and controls the application of the excitation voltage to the phase winding provided with the position sensor based on the fall of the detection signal, while controlling the phase winding not provided with the position sensor. 2. The motor control device according to claim 1, wherein the application of the excitation voltage to the line is controlled based on the rise of the detection signal of the next phase. 3. A motor control device comprising a multi-phase winding, comprising: a position sensor for detecting a relative position between a winding and a rotor for only some of the phases; While controlling the application of the excitation voltage to the windings based on the detection signal from the corresponding position sensor, the detection signal for the windings of the phase where the position sensor is not provided is based on the detection signals corresponding to the other phases. A motor control device configured to generate an artificial voltage and to control application of an excitation voltage to a winding of a phase in which the position sensor is not provided based on the artificial detection signal. 4. The multi-phase winding is a symmetric three-phase winding,
While four protrusions are arranged on the rotor at equal intervals in the circumferential direction, the position sensors are provided in each of two phases of the three phases, and each of the position sensors has a 90-degree cycle of 30 degrees. 3. The motor control device according to claim 2, wherein a detection signal having a pulse width is output, and a pseudo detection signal corresponding to the remaining one phase is generated by turning on between the two-phase detection signals. . 5. The motor control device according to claim 4, wherein application of an excitation voltage to a winding of a corresponding phase is controlled based on a fall of the detection signal or the pseudo detection signal.