JP2002112578A - Position-measuring device and motor controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a position-measuring device which has high reliability and is resistant to adverse effects, such as noises. SOLUTION: A step 840 calls and carries out a failure detection process. However, the step 840 is carried out to determine whether an error is being accumulated on a value of an electrical angle θcaused by adverse effects such as noises, and is not for detecting failures. A step 860 determines whether the error is present, large or small based on a failure code, and if it determines that the error is being accumulated at the value of the electrical angle of θ(large error), the procedure goes to a step 880. The step 880 opens at least one interrupt mask of an edge interrupt. for example, if the step 880 opens only an u-phase interrupt mask, then 'u-phase edge interrupt process' (reference point synchronizing process for the electrical angle θ) is executed, when an edge interrupt of u-phase occurs.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a positioning device having a plurality of phase sensors, and more particularly to a motor control device using the positioning device (eg, a rotation angle sensor) of the present invention. Further, the present invention can be used, for example, for a motor control device mounted on a power steering system of an automobile, a rotation angle sensor, and the like. The principle of operation of the present invention is not limited to a rotation angle sensor having a plurality of phase sensors, but also has a plurality of sensors, and a linear scale or the like which similarly measures the length and position based on periodic phase detection. It is likewise possible to apply

[0002]

2. Description of the Related Art FIG. 13 exemplifies a logical configuration diagram showing a control method when a sine wave is applied to a conventional motor control device. In this way, by feedback control centering on PI control (proportional / integral control), PWM control (chopper control), etc., for example, electronic control for outputting a desired torque value to the three-phase brushless motor M is realized. You.

FIG. 14 is a graph (a) and a definition table (b) showing the relationship between the output values A and B of the two-phase pulse sensor E of the motor control device and the area signal C. For example,
According to the calculation method and the like described in Japanese Patent Laid-Open Publication No. Hei 3-47689: a steering angle detecting device, a rotating body (eg, a steering shaft, motor The rotation direction d (or minute rotation displacement; d = 0, ± 1) of the rotor or the like can be detected.

Further, by using such a value in the rotation direction d, the rotation angle θ of the rotor of the motor M, that is, the electrical angle (one-dimensional displacement) θ of the motor M can be obtained by the following equation (1). .

Where, α is a constant indicating the size of an angle area occupied by one area signal (eg, C = 3), and is sufficiently smaller than 60 °. Value (about 0.1 ° to several degrees). Also,
θ ′ is the value of the electrical angle θ obtained in the previous control cycle. The control block 210 (angle detection) in FIG. 13 calculates the electric angle (one-dimensional displacement) θ of the motor M in this manner. The electrical angle θ is obtained by two-phase conversion, dq conversion, dq
For example, each phase of the motor M (U, V,
It is used to supply a substantially sinusoidal current to W).

On the other hand, FIG. 15 is a graph (a) and a definition table (b) showing the relationship between the output values u, v, w of the Hall element 16 of the motor control device (FIG. 13) and the phase signal S. In addition, the size of the angle area occupied by one phase signal (eg, S = 6) is 60 °. Such a phase detection unit that outputs a periodic phase signal S that indicates the rotation angle of the moving body in a stepwise manner in a predetermined phase region unit can be configured in substantially the same manner using, for example, a photoelectric element or the like. is there.

FIG. 16 is a table for judging the consistency of the motor control device. For example, according to such criteria
In the control block 230 (abnormality detection processing) of FIG. 13, the output (u, v, w) of the Hall element 16 and the pulse sensor E
And the like (A, B) are tested as needed.

[0007] When an abnormality is detected by the abnormality detection processing, for example, an abnormality processing as shown in FIG. 17 is automatically executed. However, here, FIG.
Is a flowchart illustrating a control procedure of the abnormality processing (motor stop processing) of the motor control device, and R is an adjustment coefficient of the command value iq ^* of the torque current.

[0008]

In a rotation angle sensor constituted by using the pulse sensor E as described above, the rotation angle θ is caused by an electric or electromagnetic disturbance (noise) such as static electricity or electromagnetic waves. May have unexpected errors. Further, since the rotation angle θ is calculated based on the rotation angle θ ′ obtained in the previous control cycle by a calculation method as shown in Expression (1), the error once generated is accumulated as needed with time. To go. Therefore, these errors tend to increase over time, and when the rotation angle sensor is used for a relatively long time, the reliability of the measured value of the rotation angle (electrical angle θ) of the motor M is high. There is a possibility that a problem may occur in the sex.

Further, for example, in a device having an abnormality detecting means, particularly like the above-mentioned motor control device, there is a possibility that an abnormal state is erroneously detected with an increase in the error of the detected rotation angle θ. Occurs.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to realize a highly reliable positioning device (eg, a rotation angle sensor) which is hardly affected by noise or the like. That is. A further object of the present invention is to realize a highly reliable motor control device and power steering system that are not easily affected by noise or the like.

[0011]

The following means are effective in solving the above-mentioned problems. That is, the first means includes a Hall element or a photoelectric element or the like, and outputs a periodic phase signal S that indicates the position or the rotation angle of the moving body in steps of a predetermined phase region. And a displacement detecting means for detecting in detail a one-dimensional displacement θ indicating the position or rotation angle of the moving body using a pulse sensor or the like. A reference point correcting means for executing a reference point synchronization process for adjustment periodically or periodically or when a predetermined execution condition during use of the positioning device after the initialization of the measurement system is satisfied is satisfied. It is.

Further, the second means according to the first means, wherein the abnormality of the measured value of the phase signal S or the one-dimensional displacement θ is determined by a time-dependent transition pattern of the measured value and the rate of change of the measured value. An abnormality detecting means for detecting based on an upper limit value, a lower limit value, or consistency between these two measured values, or the like is provided.

Further, the third means may be the first or second means described above.
In the means, the above-mentioned execution condition is defined based on an absolute value of a detection error of the one-dimensional displacement θ with respect to the phase signal S.

Further, the fourth means includes the first to third means.
In any one of the means, the above-described reference point correcting means is executed when the phase signal S changes.

A fifth means is that, in the fourth means, the reference point correcting means is executed based on a temporal transition pattern of the phase signal S.

The sixth means may be the fourth or fifth means described above.
In the means, the reference point correcting means is executed in parallel or asynchronously with the operation of the displacement detecting means.

Further, the seventh means includes the fourth to sixth aspects.
In any one of the means, the reference point correcting means is provided with an interrupt mask operating means relating to an edge interrupt generated when the phase signal S changes.

The eighth means may be the sixth or seventh means described above.
Means for periodically or periodically updating the one-dimensional displacement θ accompanying the periodic or periodic detection of the one-dimensional displacement θ by the displacement detecting means, the interrupt prohibition processing, the exclusive control processing, or the exclusive serial processing. The update processing of the one-dimensional displacement θ in the reference point synchronization processing in the interruption processing routine of the edge interrupt generated when the phase signal S changes due to the
Exclusive execution.

The ninth means includes the first to eighth aspects.
In any one of the means, an abnormality warning means for warning the user of the motor of a measurement system abnormality by an alarm sound, a sound, lighting or blinking of a lamp, or screen display is provided.

[0020] A tenth means is a rotation angle sensor, using a positioning device constructed using any one of the first to ninth means described above, using a rotation angle of a moving body (rotary body). Is to measure

The eleventh means uses a positioning device constructed using any one of the first to ninth means on a linear scale, and the position (displacement) of a moving body (translational body) is determined. ) Is to measure.

A twelfth means is to electronically control the rotational movement of the motor in the motor control device using the rotation angle sensor constituted by using the tenth means.

According to a thirteenth means, in the twelfth means, an abnormality processing means for stopping rotation of the motor, control of the motor or power supply to the motor is provided.

According to a fourteenth aspect, a power steering system mounted on a vehicle includes the rotation angle sensor according to the tenth aspect or the motor control device according to the twelfth or thirteenth aspect. is there. With the above means, the above-mentioned problem can be solved.

[0025]

[Effects of the invention] Even if the electrical angle θ is shifted due to noise or the like, the electrical angle θ is corrected as needed to improve the reliability of the rotation angle sensor (positioning device). . Such corrections may be made periodically or periodically,
Alternatively, it may be executed when a predetermined execution condition is satisfied. Further, such an execution condition may be defined based on, for example, the magnitude of the deviation of the electrical angle θ.

Further, by improving the measurement accuracy of the electrical angle θ in this manner, when the rotation angle sensor (positioning device) has abnormality detecting means, erroneous detection relating to abnormality detection can be avoided. In addition, due to these effects, measurement errors in the electrical angle θ caused by adverse effects such as noise, and the accumulation of these errors over time may cause the system to be abnormally stopped by the operation of the abnormal processing system. Things can be avoided.

The means (reference point correction means) for realizing the above correction processing (reference point synchronization processing) is, for example, an "edge interrupt" which can be generated when the phase signal S output from the phase detection means changes. ] Can be used. According to such a method, it is possible to configure a reference point correction unit that executes the above-described correction processing with relatively simple logic (first embodiment).

The present invention can also be applied to a case where a measuring system having no such an "edge interrupt" interrupt mechanism is configured. That is, even if the interrupt processing corresponding to the "edge interrupt" is not necessarily used, the reference point correcting means can be executed based on the temporal transition pattern of the phase signal S. It is possible to configure a reference point correction unit that executes the above (2nd embodiment).

When the "edge interrupt" is used, the update process of the electrical angle θ is performed in parallel with the interrupt process of the "edge interrupt", asynchronously with the normal periodic update process of the electrical angle θ. Be careful because it can be performed. That is, in order to surely execute the electrical angle θ update process at a desired timing by the interrupt process, the normal periodic electrical angle θ update process is performed by an interrupt prohibition process, an exclusive control process, or an exclusive serial process. It is necessary to execute it exclusively by using a conversion instruction.
This is a means for preventing the update processing of the electrical angle θ by the interrupt processing of the edge interrupt from being invalidated.

Such a phenomenon to be avoided is usually that the processing for updating the electric angle θ of the motor M according to the equation (1) is as follows.
This is caused by being realized by being developed into an interruptible machine instruction or an interruptible “string of machine instructions composed of a plurality of machine instructions”. However, when the reference point correcting means for executing the above-described correction processing is started with a high frequency, the correction processing will be executed again in the near future, so that it is not always necessary to perform such exclusive processing.

[0031]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described based on specific embodiments. However, the present invention is not limited to the embodiments described below. (First Embodiment) FIG. 1 shows a hardware configuration diagram of an electric power steering system 80 according to each embodiment of the present invention.

A steering wheel 11 is attached to one end of the steering shaft 10, and a pinion shaft 13 mounted on a gear box 12 is connected to the other end. The pinion shaft 13 is engaged with a rack shaft 14 fitted in the gear box 12, and both ends of the rack shaft 14 are connected to steering wheels via ball joints or the like (not shown).

A brushless DC motor M (hereinafter simply referred to as “motor M”) for generating assist torque is connected to the steering shaft 10 via a gear 17. This DC motor M has a driving circuit 113
The motor drive currents iu, iv, and iw for the three phases U, V, and W are supplied via the current detector 115.

Further, the steering shaft 10 includes a torque detector 15 for detecting the magnitude and the direction (steering torque τ) of the manual steering force applied to the steering wheel 11 by the driver, and the steering shaft 10 Photo interrupter 30 for detecting steering angle Θ
Is provided. The output of the photo interrupter 30 is input to a counter 32, converted into a steering angle Θ, and output. This steering angle Θ is determined by input interface (IF) 1
The steering angular velocity (dΘ / dt) is input to the CPU 110 via the CPU 14 and calculated by the CPU 110.

The motor control device 100 is provided with a rotation angle sensor (encoder) E for detecting the rotation angle of the motor M. The CPU 110 controls the two-phase pulse signals A and B output from the pulse sensor E. Based on FIG.
As described in detail below, the rotation angle θ of the motor M is detected according to the above equation (1).

The motor M is provided with a Hall element for each phase, and only the output section is shown. The phase detector 16 outputs the output values u and u of the Hall elements corresponding to the three phases, respectively. v, w are detected, amplified and waveform-shaped, and CP is input via an input interface (IF) 114.
Output to U110. However, the amplification process and the waveform shaping process may be performed by the input interface (IF) 114.

The motor control device 100 includes a CPU 110,
It comprises a ROM 111, a RAM 112, a drive circuit 113, an input interface (IF) 114, a current detector 115 and the like. The drive circuit 113 includes a battery (not shown), a PWM converter, a PMOS drive circuit, and the like.
The drive current is made substantially sinusoidal by chopper control, and the motor M
To supply power.

Further, the motor control device 100 inputs the steering torque τ, the steering angle Θ, and the vehicle speed c detected by the vehicle speedometer 50 to the CPU 110 via the input interface (IF) 114, and inputs these inputs. A command value of the “torque command” is determined by a predetermined torque calculation from the value.

FIG. 2 is a logical configuration diagram (control block diagram) showing a control method when the rectangular wave is supplied to the motor control device 100 of the electric power steering system 80. d-axis and q-axis current command values (id ^* , Ri
q ^* ) is determined based on the command value of the above “torque command”. Here, R is a coefficient of the torque current iq ^* , and may be hereinafter referred to as a torque current adjustment coefficient or simply an adjustment coefficient. In normal times, R = 1 and id ^* = 0.

When the measurement system (measurement system) is first started up, the rotation angle sensor (positioning device) 200 determines the reference point (zero point) of the rotation angle (electric angle) θ of the motor M, Since the value of the rotation angle θ is still undefined, the phase signal S is output instead of outputting the rotation angle θ. Hereinafter, such a period (output mode) is referred to as a “phase signal output mode”.
Say. In the phase signal output mode, the control block 220
The phase signal S calculated by the following equation (2) is output by (angle area detection), and each control block that executes “dq inverse conversion, three-phase conversion, two-phase conversion, dq conversion”, etc. Until the reference point (zero point) of the angle θ is determined (synchronous setting), the rectangular wave is supplied to the motor M based on the phase signal S.

[0041]

S = 4u + 2v + w (2) When such a rectangular wave is applied, for example, “0, ± 0.86”
A rectangular wave or the like which roughly approximates a sine wave with the three values is used.
Normally, such a rectangular wave is used by shifting the phase of each of the U, V, and W phases by １ ／ cycle (120 ° in terms of electrical angle θ).

FIG. 3 is a flowchart (first half) illustrating a control procedure of the rotation angle sensor (positioning device) 200 of the motor control device 100. In this control procedure, first,
In step 305, output values u, v, w of each phase of the Hall element 16 are input. In step 310, equation (2)
To obtain the phase signal S. In step 315, the value of the output mode flag sw1 is set to 0 (phase signal output mode).
Set to. When this flag is 0, the phase signal S is output from the rotation angle sensor (positioning device) 200.

In step 320, an application program using the output value (phase signal S or electrical angle θ) of the rotation angle sensor (positioning device) 200, that is, “dq inverse conversion, three-phase conversion, two-phase conversion, or For a control program (control block) that executes “dq conversion” or the like, the output mode flag sw
1 and the value of the phase signal S are output.

In step 325, all the interrupt masks of the edge interrupt are opened. However, the “edge interrupt” here is an interrupt that occurs when the phase signal S changes, and as can be seen from FIG.
= 30 °, 210 ° is called a u-phase edge interrupt, θ = 150 °, 330 ° is called a v-phase edge interrupt, and θ
= 90 ° and 270 ° are called w-phase edge interrupts.

When the edge masks of these edge interrupts are all open and, for example, a u-phase edge interrupt occurs, the later-described interrupt processing (reference point synchronization processing) illustrated in FIG. 4 is executed. You.

In step 330, the process waits for completion of the interrupt process (reference point synchronization process). This interrupt processing (Fig. 4)
As a result, the accurate value of the current electrical angle of the motor M is set in the variable θ. Therefore, the output value of the rotation angle sensor (positioning device) 200 is fixed to the value output in step 320 until the completion of the interruption process is completed.

In step 335, the output values u, v, w of each phase of the Hall element 16 are input. In step 340, the phase signal S0 is initialized by the equation (2). Here, the phase signal S0 is a variable (a save area) for saving a past value for one control cycle of the phase signal S. Further, the length of this one control cycle (ΔT seconds) is determined based on the specifications of the motor M to be controlled and the like. For example, in the case of the present motor control device, it is set to about 1 to 25 ms.

At step 350, the output mode flag s
The value of w1 is changed to 1 (electrical angle output mode). In step 355, the output mode flag sw1 and the value of the electrical angle θ are output to the application program using the output value (the phase signal S or the electrical angle θ) of the rotation angle sensor (positioning device) 200. By this output, “dq inverse transform, 3
In the above-described application program for performing “phase conversion, two-phase conversion, or dq conversion”, the motor M
Can be executed (started).

When energizing the rectangular wave, "0, ± 0.8
Although a use example of a rectangular wave or the like which roughly approximates a sine wave with three values of 6 ”has been described, the sine wave used when the sine wave is energized as described above generally has a function of several tens to several thousands. Using the values, it is approximated relatively accurately. In addition, these sine waves are, as in the case of the rectangular wave energization described above, usually 1/3 cycle of each phase of each of the U phase, V phase, and W phase (120 degrees in terms of electrical angle θ). °).

In step 360, the value of the waiting time T is set to the sum of the current time (timer time) t and the length ΔT of one control cycle. In step 365, the pulse sensor E
Output values A and B are input. In step 370, the current value of the B-phase output signal B is stored in a variable (save area) B0 for saving a past value of the B-phase output signal B for one control cycle. Initialize B0.

In step 375, the value of the current area signal C (= 2) is set in a variable (save area) C0 for saving the past value for one control cycle of the area signal C in FIG.
By storing (A + B), the variable C0 is initialized. In step 380, other variables are initialized as necessary.

FIG. 4 shows a rotation angle sensor (positioning device) 200.
Of the asynchronous processing (u
9 is a flowchart illustrating a control procedure of (phase edge interrupt processing). In this u-phase edge interrupt processing, first, in step 410, the interrupt mask of the u-phase edge interrupt is closed. Next, in step 420,
The values (v, w) of the v-phase and w-phase output by the Hall element are input.

In step 430, the values of the v-phase and the w-phase are determined, and if "v = 0 and w = 1", step 44
If not, the process moves to step 450. In step 440, the value of the electrical angle θ is set to 30 °.
In step 450, the values of the v phase and the w phase are determined, and “v
= 1 and w = 0 ", the process proceeds to step 460; otherwise, the process proceeds to step 470.

In step 460, the value of the electrical angle θ is set to 21
Set to 0 °. In step 470, predetermined exception processing is executed. Similar electrical angle setting processing (reference point synchronization processing) is also configured for each of the v-phase and w-phase edge interrupt processing.

The initial processing of the rotation angle sensor (positioning device) 200 is executed by the above processing shown in FIGS.

FIG. 5 is a flowchart illustrating a periodic control procedure after completion of the initial processing of the rotation angle sensor (positioning device) 200 of the motor control device 100. Step 50
At 5, the control waits until the current time (timer time) t becomes equal to or greater than the value of the waiting time T. In step 510, the output values A and B of the pulse sensor E are input.

In step 515, the rotation direction (small amount of rotation) d of the motor M is obtained by the subroutine shown in FIG. 7, which is constructed based on the output determination table shown in FIG. However,
Here, FIG. 6 is an output determination table used as a determination criterion when determining the rotation direction d of the motor based on the output value of the two-phase pulse sensor E. The motor M has a predetermined control period (ΔT). In the meantime, the angle α shown in FIG.
It is made on the basis of the physical precondition that it will not rotate more than [°]. FIG. 7 is a flowchart illustrating a processing procedure for calculating the rotation direction d of the motor from the output value of the two-phase pulse sensor E.

In this flowchart, first, at step 710, the area signal C defined in FIG. 14 is obtained. Here, A and B are each 1-bit information (1-bit variable), and C is 2-bit information (2-bit variable).
It is. In step 720, the area signal C obtained in step 710 and the value C of the area signal obtained in the previous control cycle are determined.
An exclusive OR (XOR) operation is performed by matching 0 with each corresponding bit.

In step 730, the value of the rotation direction d is set to 0.
(No rotation). In step 740, the value A of the current A phase is compared with the value B0 of the previous B phase, and if they are equal, d = + 1 (forward rotation); otherwise, d = -1.
The value of the rotation direction d is set in (negative rotation). In step 770, the value B of the current B phase is set to a variable B0, and
In step 780, the value of the current area signal C is set to the variable C0.
Are respectively stored (evacuated).

Step 515 in FIG. 5 is realized by the above-described rotation direction d calculation processing. Thereafter, in step 520 of FIG. 5, the motor M
Is updated. However, this update processing is executed exclusively with respect to the update processing of the electrical angle θ in the interrupt processing routine of FIG. 4 by an interrupt prohibition processing, an exclusive control processing, an exclusive serialization instruction, or the like. Thereby, “FIG. 1 described later
FIG. 4 executed after step 880 of 0
Of the electrical angle θ (step 440 or step 460) competes with the update process of step 520, and the update process of θ overlaps, resulting in a correction process of the electrical angle θ (step 440 or step 460). ) Becomes invalid. This phenomenon is caused by the process of updating the electric angle θ of the motor M according to the equation (1) (step 52).
0) is developed and realized as an interruptible machine instruction or an interruptible “string of machine instructions composed of a plurality of machine instructions”.

Thereafter, in step 525 of FIG. 5, the output values u, v, w of each phase of the Hall element 16 are input. In step 530, the phase signal S is obtained by the equation (2). In step 535, the value of the safety constant δ in the above-described consistency determination criterion table (FIG. 16) to be referred to in the abnormality detection processing (FIG. 8) in the next step 540 is set.

Here, the standard value δ0 of the safety constant δ is determined, for example, as follows.

Δ0 = (Hysteresis error of Hall element) + (Margin) (3) However, when the phase detector is constituted by the photoelectric element, the term “Hysteresis error of Hall element” is not required.

In step 540, for example, an “abnormality detection process” illustrated in FIGS. 8 and 9 is executed. FIG.
It is a flowchart which illustrates the control procedure of abnormality detection processing (consistency determination processing) of the present rotation angle sensor (positioning device) 200. FIG. 9 is a definition table of the array C (S) referred to in the abnormality detection processing (FIG. 8).

For example, according to the present abnormality detection processing, when an abnormality specified in the above-described consistency determination reference table (FIG. 16) is continuously detected over J control cycles, a predetermined abnormality code is generated. Is set. However, J is an arbitrary natural number. In particular, when J = 1, an abnormality code is set immediately when these abnormalities are detected once. Further, such an abnormality may be classified into the above-described abnormality codes according to the frequency of occurrence of the abnormality which is intermittently detected. Further, such an abnormality is caused by, for example, an exceptional event of a phase signal transition pattern between the value S0 of the phase signal detected in the previous control cycle and the value S of the phase signal detected in the current control cycle. You may make it detect.

At step 545, based on the abnormality code which can be set in the abnormality detection processing described above, the measured values u, v,
It is determined whether or not w or at least one of the measurement values A and B has an abnormality. If an abnormality has occurred, the process proceeds to step 550; otherwise, the process proceeds to step 555. Step 550
Then, for example, the above-described abnormality processing (motor stop processing) as illustrated in FIG. 17 is executed.

In step 555, the output mode flag sw1 and the value of the electrical angle θ are applied to the application program using the output value (phase signal S or electrical angle θ) of the present rotation angle sensor (positioning device) 200. Output. With this output, the application program that executes “dq inverse conversion, three-phase conversion, two-phase conversion, or dq conversion” or the like can execute (continue) the drive control of the motor M by sine wave conduction.

At step 560, reference point synchronization processing is performed. In the present step 560, the processing of opening all the interrupt masks of the edge interrupt illustrated in FIG. 3 (step 32)
Processing equivalent to 5) may be executed unconditionally. According to such a configuration, “u-phase edge interrupt processing” in FIG.
“V-phase edge interrupt processing” and “w-phase edge interrupt processing” configured in the same manner are executed each time an edge interrupt occurs. In addition, step 56
In the case of 0, when opening the interrupt mask of the edge interrupt, for example, only the w-phase interrupt mask may be opened. However, in the first embodiment, step 56
The reference point synchronization process of 0 is executed by a subroutine shown in FIG.

FIG. 10 is a flowchart illustrating a control procedure for executing (starting) the reference point synchronization processing of the electrical angle (one-dimensional displacement) θ in the first embodiment. In this subroutine, first, in step 820, the value of the safety constant δ is set in substantially the same manner as in step 535 of FIG. 5 described above. However, in this step 820, this safety constant δ
Is stored in a variable δ after being multiplied by γ (0 <γ <1). For example, the value of γ is 1/10, 1/5, 1
/ 3, 1/2, etc. The value of γ is, for example, the frequency of occurrence of noise, the expected value of the magnitude of an error in the electrical angle θ per noise, the length ΔT of one control cycle, and the characteristics of the control target (motor M, etc.). The optimum value may be selected according to the various conditions.

In step 840, the above-described abnormality detection processing of FIG. 8 is called and executed. However, this step 84
0 is not executed for the purpose of detecting an abnormality, but is an electrical angle (one-dimensional displacement) due to adverse effects such as noise.
This is performed for the purpose of determining whether or not an error is being accumulated in the value of θ. Step 8
The subroutine (abnormality detection processing) called at 40 need not necessarily be the same subroutine as the subroutine (abnormality detection processing) called at step 540 in FIG. That is, these subroutines may be prepared individually (for each purpose).

In step 860, the presence or absence or magnitude of the error is determined based on the abnormal code, and it is determined that an error is being accumulated in the value of the electrical angle (one-dimensional displacement) θ (large error). In this case, the process proceeds to step 880; otherwise, the process (control) is transferred to the calling source. In step 880, at least one of the interrupt masks of the edge interrupt is opened. For example, if only the u-phase interrupt mask is opened by the operation of step 880, then, when a u-phase edge interrupt occurs, the “u-phase edge interrupt processing” in FIG. Synchronous processing) is executed.

However, it is more desirable to open all the interrupt masks of each phase of u, v, w in order to quickly perform the correction (reference point synchronization processing). In particular, when the value of γ is set relatively large, it is more desirable to open all the interrupt masks of each phase in order to quickly perform the correction.

Thereafter, step 565 of the caller (FIG. 5)
Then, the current value of the phase signal S is saved in the variable S0. In step 570, the value of the waiting time T is increased by the length ΔT of one control cycle and reset, and the process (control) is returned to step 505.

According to the above control procedure, the error of the electrical angle θ caused by the adverse effect of noise and the like and the accumulation of these errors with the lapse of time cause the system (motor control device 100) to operate by the abnormality processing system. Can be avoided beforehand.

As described above, the means for executing the correction processing (reference point synchronization processing) can be constituted by utilizing the "edge interrupt" generated when the phase signal S output from the phase detection means changes. According to such a configuration, as described above, the correction processing can be realized with relatively simple logic.

(Second Embodiment) In the first embodiment described above, the means for executing the correction processing (reference point synchronization processing) is configured by using the "edge interrupt" interrupt mechanism.
The present invention can also be applied to a device that does not have such an “edge interrupt”.

FIG. 11 is a flowchart illustrating a control procedure of a subroutine for executing the reference point synchronization processing of the electric angle θ in the second embodiment. This subroutine
The "reference point synchronization" processing in step 560 in FIG. 5 is to be called and executed instead of the subroutine (reference point synchronization processing (1)) in FIG. 10 used in the first embodiment.

In this subroutine, first, at step 910, a flag F indicating whether or not the reference point synchronization processing needs to be executed is performed.
The value of 1 is determined, and if 0 (unnecessary), the process proceeds to step 920.
Otherwise, the process proceeds to step 950. However, the initial value of the flag F1 is 0, and this initialization is performed as shown in FIG.
Step 380 is performed. In step 920, a value of γ times (0 <γ <1) the standard value δ0 is set as the safety constant δ, just like step 820 in FIG. In step 925, the subroutine "abnormality detection processing" in FIG. 8 is called and executed.

In step 930, the presence or absence or magnitude of the error is determined based on the abnormal code, and it is determined that the error is being accumulated in the value of the electrical angle (one-dimensional displacement) θ (large error). In this case, the process goes to step 950; otherwise, the process (control) is transferred to the caller. In step 950, if the current value of the phase signal S is "5", step 96 is executed.
The process moves to 0, otherwise to step 990.

At step 960, the value S0 of the previous phase signal (one control cycle before) is checked, and if "4", the process proceeds to step 965, otherwise to step 970. In step 965, the electrical angle θ is set to 90 °, and then the process proceeds to step 980. Step 9
In step 70, the value S0 of the previous phase signal (one control cycle before) is checked, and if "1", the process proceeds to step 975; otherwise, the process proceeds to step 990. Step 975
Then, the electrical angle θ is set to 30 °, and thereafter, step 98
Move the process to 0.

At step 980, the value of the flag F1 is set to 0
(No need to execute reference point synchronization). Step 99
At 0, the value of the flag F1 is set to 1 (necessary to execute the reference point synchronization processing). Thereafter, the processing (control) is returned to the calling source.

For example, the reference point synchronization processing of the present invention can be realized by the above-described subroutine instead of the subroutine (reference point synchronization processing (1)) of FIG. 10 used in the first embodiment. . According to the above configuration, when it is determined that an error is accumulating in the value of the electrical angle θ (large error), when the value of the phase signal S transitions from another value to “5”, the electrical angle Correction of θ (reference point synchronization) is performed.

The value of the phase signal S to be checked in this way does not have to be “5”, and the value is arbitrary. Also,
The value of the phase signal S to be checked in this way is not limited to one, and the combination is arbitrary. For example, with such a configuration, it is possible to obtain substantially the same timing as that of the edge interrupt based on the temporal transition pattern of the phase signal S, and thereby it is possible to execute the reference point correcting means at an accurate timing. .

Incidentally, in an apparatus having no "edge interrupt", the "phase signal output mode" (step 30) shown in FIG.
5 to step 340) ”also needs to be changed. FIG. 12 is a flowchart illustrating a control procedure (subroutine) to be executed in the first “phase signal output mode” when the system is started in the second embodiment. This subroutine is to be executed instead of Steps 305 to 340 in FIG. 3 when the “edge interrupt” is not used.

In this subroutine, first, at step 120, the value S of the phase signal of the previous time (one control cycle before) is obtained.
Initialize 0 to 0. However, the initial value set here is arbitrary as long as it is a numerical value other than “2” and “4”.

In step 125, the current time (timer time) t is set as the waiting time T. In step 130,
The value of the output mode flag sw1 is set to 0 (phase signal output mode). When this flag is 0, the phase signal S is output from the rotation angle sensor (positioning device) 200.

In step 135, the output values u, v, w of each phase of the Hall element 16 are input. In step 140, the phase signal S is obtained by the equation (2). Step 1
At 45, the output mode flag sw1 and the value of the phase signal S are output to an application program that uses the output value (phase signal S or electrical angle θ) of the rotation angle sensor (positioning device) 200. In step 150, if the current value of the phase signal S is "6", the process proceeds to step 155; otherwise, the process proceeds to step 180.

At step 155, the value S0 of the previous phase signal (one control cycle before) is checked, and if "4", the process proceeds to step 160; otherwise, the process proceeds to step 165. In step 160, the electrical angle θ is set to 150 °, and then the process proceeds to step 175. In step 165, the value S0 of the previous phase signal (one control cycle before)
Is checked, and if "2", the process proceeds to step 170; otherwise, the process proceeds to step 180. Step 17
At 0, the electrical angle θ is set to 210 °, and then the process proceeds to step 175. In step 175, the current value of the phase signal S is saved in the variable S0, and then the process (control) is returned to the calling source.

On the other hand, in step 180, the value of the current phase signal S is saved in the variable S0. In step 185,
The value of the waiting time T is increased and reset by the length of one control cycle ΔT. In step 190, wait until the current time (timer time) t becomes equal to or greater than the value of the waiting time T,
Thereafter, the process (control) is returned to step 135.

For example, the subroutine as described above can also constitute a process instead of the process of “phase signal output mode (steps 305 to 340)” in FIG. According to the above configuration, when the value of the phase signal S transits from another value to “6”, the initial setting of the electrical angle θ (reference point synchronization) is performed.

The value of the phase signal S to be checked in this way does not have to be “6”, and its value is arbitrary. Also,
The value of the phase signal S to be checked in this way is not limited to one, and the combination is arbitrary. With these configurations, it is possible to obtain substantially the same timing as that of the edge interrupt.

For example, according to the above configuration example, the present invention can be applied to a device having no "edge interrupt". Also, according to the above configuration example,
Even if the electrical angle θ shifts due to noise or the like, the reliability of the rotation angle sensor (positioning device) is improved by applying correction to the electrical angle θ as needed. In addition, by improving the measurement accuracy of the electrical angle θ in this manner, the rotation angle sensor (positioning device) can avoid erroneous detection by the abnormality detection unit.

In each of the above embodiments, the electric angle (phase) of “0 ° ≦ θ <360 °” is exemplified as the one-dimensional displacement θ. However, these one-dimensional displacements θ are generally not necessarily limited to the upper limit. And does not have a lower limit. To eliminate these upper and lower limits, a known or arbitrary counting means is used to change the phase signal S from the absolute reference point in one cycle unit, such as the number of rotations in a predetermined direction. (Displacement)
May be managed (counted) at the same time.

In each of the above embodiments, the one-dimensional displacement θ
Was described as “angle”, but these one-dimensional displacements θ
May generally be "length". That is, the present invention can be applied to a linear scale or the like for measuring the length of a line segment or a curve as in the above-described embodiment.

[Brief description of the drawings]

FIG. 1 is a hardware configuration diagram of an electric power steering system 80 according to each embodiment of the present invention.

FIG. 2 is a logical configuration diagram showing a control method when a rectangular wave is applied to a motor control device 100 of the electric power steering system 80.

FIG. 3 is a flowchart (first half) illustrating a control procedure of a rotation angle sensor (positioning device) 200 of the motor control device 100;

FIG. 4 is a flowchart illustrating a control procedure of an asynchronous process (u-phase edge interrupt process) started by the rotation angle sensor (positioning device) 200 when an edge interrupt occurs.

FIG. 5 is a flowchart (second half) illustrating a control procedure of a rotation angle sensor (positioning device) 200 of the motor control device 100;

FIG. 6 is an output determination table used as a criterion for determining the rotation direction d of the motor from the output value of the two-phase pulse sensor E;

FIG. 7 is a flowchart illustrating a processing procedure for calculating a rotation direction d of a motor from an output value of a two-phase pulse sensor E;

FIG. 8 is a flowchart illustrating a control procedure of an abnormality detection process (consistency determination process) of the rotation angle sensor (positioning device) 200;

FIG. 9 is a definition table of an array C (S) referred to in abnormality detection processing of the rotation angle sensor (positioning device) 200.

FIG. 10 is a flowchart (1) illustrating a control procedure for executing (starting) reference point synchronization processing of one-dimensional displacement θ in the first embodiment.

FIG. 11 is a flowchart (2) illustrating a control procedure for executing a reference point synchronization process of one-dimensional displacement θ in the second embodiment.

FIG. 12 is a flowchart illustrating a control procedure (subroutine) to be executed in a first phase signal output mode at the time of system startup in the second embodiment.

FIG. 13 is a logical configuration diagram showing a control method when a sine wave is applied to a conventional motor control device.

FIG. 14 is a graph (a) and a definition table (b) showing the relationship between the output values A and B of the two-phase pulse sensor of the conventional motor control device and the area signal C.

FIG. 15 is a graph (a) and a definition table (b) showing the relationship between the output values u, v, w of the Hall element 16 of the conventional motor control device and the phase signal S.

FIG. 16 is a table for determining the consistency of a conventional motor control device.

FIG. 17 is a flowchart illustrating a control procedure of an abnormal process (motor stop process) of the conventional motor control device.

[Explanation of symbols]

M: brushless DC motor E: two-phase pulse sensor (incremental encoder) 10: steering shaft 15: torque detector 16: phase detection device (Hall element) 80: electric power steering system 100: motor control device 113: drive circuit 230 … Control block for abnormality detection processing A… Output value of A-phase pulse sensor B… Output value of B-phase pulse sensor θ… One-dimensional displacement (rotation angle (electric angle) of rotor of motor M) τ… Steering torque Θ … Steering angle c… Vehicle speed id ^* … d-axis command current iq ^* … q-axis command current idf… d-axis measurement current (feedback current) iqf… q-axis measurement current (feedback current) ΔId … Current deviation of d axis ΔIq… current deviation of q axis S… phase signal u… of U-phase Hall element Output value v: Output value of V-phase Hall element w: Output value of W-phase Hall element R: Torque current adjustment coefficient

Continued on the front page F-term (reference) 2F069 AA86 DD30 EE00 FF01 GG06 GG07 HH14 HH15 NN00 QQ03 2F077 AA03 AA10 AA37 AA38 AA49 JJ08 TT04 TT21 TT31 TT33 TT52 TT62 3D033 CA13 CA10 CA01 DC07 CA20 SS02 TT02 TT11 TT12 TT15 XA02 XA12 XA13

Claims (14)

[Claims] 1. A phase detecting means having a Hall element or a photoelectric element and outputting a periodic phase signal S representing a position or a rotation angle of a moving body stepwise in a predetermined phase region unit; A displacement detecting means for detecting the one-dimensional displacement θ indicating the position or the rotation angle of the body in detail using a pulse sensor or the like, wherein the phase adjustment of the one-dimensional displacement θ with respect to the phase signal S or the zero point is performed. Reference point correcting means for executing a reference point synchronization process for adjustment periodically or periodically, or when a predetermined execution condition during use of the positioning device is satisfied after initialization of the measurement system is completed. A positioning device comprising: 2. The abnormality of the measured value of the phase signal S or the one-dimensional displacement θ is determined by a transition pattern of the measured value with time, an upper limit or a lower limit of a rate of change of the measured value, or both of the measured values. 2. The positioning device according to claim 1, further comprising an abnormality detection unit that detects an abnormality based on, for example, consistency between the positioning devices. 3. The positioning apparatus according to claim 1, wherein the execution condition is defined based on an absolute value of a detection error of the one-dimensional displacement θ with respect to the phase signal S. . 4. The positioning device according to claim 1, wherein the reference point correction unit is executed when the phase signal S changes. 5. The positioning apparatus according to claim 4, wherein said reference point correcting means is executed based on a temporal transition pattern of said phase signal S. 6. The positioning apparatus according to claim 4, wherein the reference point correction unit is executed in parallel or asynchronously with the operation of the displacement detection unit. 7. The apparatus according to claim 4, wherein said reference point correcting means has an interrupt mask operating means for an edge interrupt generated when said phase signal S changes. A positioning device as described. 8. The one-dimensional displacement θ accompanying the periodic or periodic detection of the one-dimensional displacement θ by the displacement detecting means.
The periodic or periodic update process is performed by an interrupt prohibition process, an exclusive control process, or an exclusive serialization instruction, etc., in the edge interrupt interrupt process routine that occurs when the phase signal S changes. The positioning apparatus according to claim 6, wherein the update processing of the one-dimensional displacement θ in the reference point synchronization processing is executed exclusively. 9. An abnormality warning means for warning a user of the motor of an abnormality of the measurement system by alarm sound, voice, lighting or blinking of a lamp, or screen display. The positioning device according to any one of claims 1 to 8. 10. A rotation angle sensor for measuring a rotation angle of the moving body using the positioning device according to claim 1. Description: 11. A linear scale, wherein the position of the moving body is measured using the positioning device according to any one of claims 1 to 9. 12. A motor control device using the rotation angle sensor according to claim 10 to electronically control the rotation of the motor. 13. The motor control device according to claim 12, further comprising abnormality processing means for stopping rotation of the motor, control of the motor, or power supply to the motor. 14. A power steering system mounted on a vehicle, comprising: the rotation angle sensor according to claim 10; or the motor control device according to claim 12 or 13.