JP2846504B2 - Motor control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor controller for monitoring the operation of a motor, for example, disturbance torque and controlling the speed of the motor.

[0002]

2. Description of the Related Art In a device such as a VTR, improvement of a motor control technique is important for ensuring reliability of the device and reducing its size. In particular, the performance of a motor used for driving a drum or a capstan of a VTR greatly affects image quality and sound quality. Therefore, in recent years, there has been an increasing demand for VTR motor control.

Conventionally, the performance of motor control in a VTR has been improved by digitization and software. However, in such a study direction, there are certain limits or obstacles in improving the wow and flutter, the degree of disturbance suppression, the control rigidity against variations in the motor, and the like.

In order to remove such limitations or obstacles, there has been proposed a configuration in which a modern control theory is used in capstan control of a VTR and a disturbance removal loop is provided by a disturbance estimation observer (refer to "Disturbance estimation. VT
Robust control of R capstan motor ", Journal of the Institute of Television Engineers of Japan, vol.44, No.11, pp.1618-1621 (1990), Nagasawa et al.,
reference. ).

FIG. 16 shows a configuration of a conventional motor control device configured using a disturbance estimation observer.
The device shown in this figure assumes a VTR drum motor and a capstan motor as motors to be controlled.

The device shown in FIG. 1 is a device for controlling the motor (1) by PWM (Pulse Width Modulation). That is, P which converts the speed error signal into a PWM signal
A WM converter (2) is provided. A low-pass filter (hereinafter, referred to as LPF) (3), an amplifier (4), and a motor drive amplifier (hereinafter, referred to as MDA) (5) are provided in the subsequent stage of the PWM converter (2). LP
F (3) is a filter for removing a PWM carrier frequency component from the PWM signal, and its output is an analog voltage. The amplifier (4) amplifies the analog voltage output from the LPF (3) and supplies it to the MDA (5). MDA
(5) converts the analog voltage amplified by the amplifier (4) into a current to be supplied to the motor (1), that is, a drive current I.

[0007] The drive current I is supplied to the motor (1) and the disturbance estimation observer (7) via the adder (6).
The motor (1) is driven by the output of the adder (6),
It rotates at an angular velocity ω. The disturbance estimation observer (7) takes in the output of the adder (6) and also takes in the angular velocity ω of the motor (1) as an electric signal. Disturbance estimation observer (7) generates a observer operation signal in response to these inputs, feeds forward to the adder (6). The adder (6) converts the observer operation signal into an MDA (5)
, The drive current I actually supplied to the motor (1) and the disturbance estimation observer (7) has a value reflecting the observer calculation signal output from the disturbance estimation observer (7). That is, the feed related to the disturbance estimation
A forward loop is formed.

In this conventional example, a speed error calculator (8) is provided. The speed error calculator (8) takes in an electric signal representing the angular speed ω, generates a speed error signal, and supplies the speed error signal to the PWM converter (2). PW
Since the M signal is generated according to the speed error signal,
It can be said that the speed error calculation section (8) forms a feedback loop related to the speed control of the motor (1).

In practice, a phase control system (system for detecting the rotational phase of the motor (1) and performing feedback control) is provided, but is omitted here for simplification of description.

FIG. 17 is a block diagram showing the apparatus shown in FIG. In this figure, the motor (1) is represented as a current-torque converter (9) and a torque-rotation converter (10). The current-torque converter (9) is a block showing a portion of the motor (1) that converts the drive current I, which is the output of the adder (6), into a drive torque T _M. 10) is a block showing a part for converting the torque _TM into the angular velocity ω. Therefore, the transfer function of the current-torque converter (9) is a torque constant _KT , and the transfer function of the torque-rotation converter (10) is the first-order lag function 1 based on the inertia J and the viscous damping coefficient D of the motor (1). / (Js + D).

[0011] However, in this figure, the current - torque conversion section (9) and torque - subtracters during rotation conversion unit (10) (1
1) is drawn. The subtraction unit (11), the current - a block obtained by modeling that the influence of the disturbance torque T _G at which the torque T _M output torque converting portion (9) applied. Thus, the actual torque - a disturbance torque T _G - rotating transformer (10) is strictly torque being inputted to the T _M rather than torque T _M.

In this figure, the transfer function of the PWM converter (2) is represented as a PWM conversion gain K _PWM , and the transfer function of the LPF (3) is H _LPF (s).
Is represented. Further, the amplifier (4) and the MDA
Composite transfer function (5) are shown in block (12) as a conversion gain K _A (hereinafter, referred to as amplifier section).

Next, the speed error calculating section (8) is depicted as an FG section (13), a speed detecting section (14), and a speed system coefficient section (15) in FIG. The FG unit (13) converts the angular velocity ω into an electric signal to convert the angular velocity ω into an FG (Frequency generato).
r) Output as a signal. The FG signal is a signal having a rise / fall synchronized with the rotation of the motor (1). In this figure, the number of FG pulses (the number of rising or falling) per one rotation of the motor is shown as _KFG . The FG signal is taken into the speed detector (14). The speed detection unit (14) has a transfer function H _F (s), detects the rotation speed ω based on the FG signal, and supplies the rotation speed ω to the speed system coefficient unit (15). Speed system coefficient part (15)
Multiplies the speed-based coefficients K _F and generates a speed control signal to the output of the speed detector (14) to the PWM converter (2).

On the other hand, the disturbance estimation observer (7) includes a configuration in which the drive current I is multiplied by _KT · g. In FIG. 17, this configuration includes a voltage conversion unit (16), an A / D conversion unit (17), a current conversion unit (18), and a multiplication unit (19).
It is composed of The voltage converter (16) converts the drive current I by a conversion gain R to convert the drive current I into a voltage signal. A / D
The conversion unit (17) performs A / D conversion on the voltage signal and outputs a digital value. Conversion gain of the A / D conversion unit (17) _{is F AD.} The current converter (18) multiplies the output of the A / D converter (17) by a coefficient α, and supplies the result to the multiplier (19). Here, the coefficient α = 1 / (R · F _AD ). Therefore, the output of the current conversion unit (18) corresponds to a value obtained by converting the drive current I into a digital value with a conversion gain of 1. The multiplication unit (19) multiplies this digital value by _KT · g. Here, K _T is a torque constant, as mentioned above, which by multiplying to the digital value, the current - output serving torque T _M of the torque converter unit (9) is estimated.
g is a constant for determining a disturbance suppression band by the disturbance estimation observer (7). The output of the multiplication unit (19) is supplied to an adder (20).

In the disturbance estimation observer (7), the angular velocity ω is taken in by the multipliers (21) and (22).
It is. In practice, the angular velocity ω is not directly taken in, but rather the angular velocity ω is detected based on the FG signal. However, in this case, the angular velocity ω is directly taken in for simplification of the drawing. The multiplication unit (21) calculates the angular velocity ω by J ·
The g ^2, multiplication section (22) is a J · g, multiplied respectively.
The output of the multiplication unit (21) is added to the output of the multiplication unit (19) in the adder (20) and supplied to the subtractor (24) via the first-order lag element (23). First order delay element (2
3) is a digital filter having a transfer function of 1 / (s + g), so that the output of the adder (20) is delayed by a time corresponding to g. The subtractor (24)
The output of the multiplication unit (22) is also supplied, and the subtractor (2
4) subtracts the output of the multiplier (22) from the output of the multiplier (23). The output of the subtractor (24) is, in this figure, T _G
Indicated by ＾.

_TG } corresponds to an estimated value of the disturbance torque _TG . This is shown in FIG. 3 and Equations (3) to
(5) (indicating the shape of the minimum dimension observer of Gopinas). That is, the disturbance estimation observer (7) of this conventional example is an example configured as a minimum-dimensional observer.

The disturbance torque T which is the output of the subtractor (24)
_G estimate _{T G} ^ is the multiplication unit (25), the voltage conversion unit (2
6), and are sequentially supplied to the D / A converter (27) and the current converter (28). The multiplier (25) multiplies the estimated value _TG by a conversion gain 1 / _KT , and supplies the result to the voltage converter (26). The voltage converter (26) converts the signal supplied from the multiplier (25 ) into a voltage signal by multiplying the signal by the conversion gain β, and supplies the voltage signal to the D / A converter (27). The D / A converter (27) performs D / A conversion on this voltage signal. The conversion gain is _FDA . A current converter (28) multiplies the D / A-converted voltage signal by 1 / R to convert the voltage signal into a current signal;
It is supplied to the adder (6). Here, the voltage conversion unit (26)
Is the R / _FDA .

This conventional device has the configuration as described above. Next, the operation of this conventional example will be described.

In this conventional example, an FG signal corresponding to the angular velocity ω of the motor (1) is generated in the FG section (13), and the speed detection section (14) detects the rising or falling of the FG signal, and The time interval is detected as a cycle. The speed system coefficient section (15) outputs a speed error signal having a value corresponding to the cycle, and the PWM control of the motor (1) is performed based on the signal so that the motor (1) rotates at a predetermined angular speed.

[0020] Here drive dynamic current I及 beauty angular velocity ω is taken into the disturbance estimation observer (7), a disturbance estimating observer (7) obtains the estimated value T _{G ^} Based on these, the estimated value T _{G ^} An observer operation signal having a corresponding value is output to the adder (6). The addition section (6) adds the output of the amplification section (12) and the observer operation signal, and controls the motor (1) to rotate at a predetermined angular velocity based on the addition result. As a result of this control, the motor (1) rotates so that the disturbance torque _TG applied to the motor (1) is canceled.

[0021]

As described above, conventionally, it has been possible to drive the motor so as to cancel the disturbance torque. However, as described above, in order to reduce the size and increase the reliability of the apparatus. It is better to implement the device using software as much as possible. In FIG. 17, what can be implemented by software (that is, realized by a certain type of processor) is mainly the part after the A / D converter (17) and the part up to the D / A converter (27). That is, it is the part shown by the broken line (29) in the figure. In other words, in order to implement the device by the software servo system, the A / A
D conversion and D / A conversion are required.

As a result, this necessitates hardware for A / D conversion and D / A conversion, which hinders software implementation. In addition, the time delay caused by the A / D conversion and the D / A conversion acts as a time delay element of the disturbance estimation observer, causing deterioration of control performance.

An object of the present invention is to solve such a problem, and an object of the present invention is to provide a motor control device which does not hinder software implementation and has good control performance. Also, by applying this device, FG
It is an object of the present invention to provide a device that can reduce the duty unevenness of a signal and a device with improved operation at the time of starting.

[0024]

[Means for Solving the Problems]

According to the present invention, a digital value control signal
Drive means for driving the motor by means of
Generates a square wave signal according to the
Speed detection to detect the rotation speed of the above motor by digital value
Output means and the motor based on the output of the speed detection means.
Speed error calculating means for calculating the speed error of the motor, and the motor
Phase detection means for detecting the rotation phase of
The phase error of the motor based on the output of the phase detection means
And a phase error calculating means for calculating
Disturbance torque that estimates and outputs the disturbance torque as a digital value
The invention relates to a motor control device having an observer.
You.

According to a first aspect of the present invention, there is provided an adding means for adding the output of the speed error calculating means, the output of the phase error calculating means and the output of the disturbance torque observer as a digital value, and a motor based on the added output. Drive means to drive
And duty unevenness correcting means for correcting the duty unevenness of the square wave signal generated by the speed detecting means, wherein the disturbance torque observer outputs the output of the speed detecting means in which the duty unevenness has been corrected and the output of the adding means. by estimating the disturbance torque applied to the motor based on an output,
The motor is controlled based on the added output .

Next, a second aspect of the present invention is the above-described dute.
The unevenness correcting means firstly includes the same signal included in the square wave signal.
Calculate the average length of a single period, and calculate this average length
Subtracted from the length of time between
The present invention is characterized by correcting cutie unevenness .

Further , claim 3 of the present invention provides the above-mentioned phase detection.
Motor rotation based on the rotation phase detected by the
Phase for determining whether phase lock-in has been performed
Synchronization pull-in determination means
Only when the phase error is detected by the adding means.
The output of the difference calculation means is added .

[0029]

According to the first aspect of the present invention, the motor is driven according to the control signal of the digital value. The speed detecting means generates a square wave signal according to the rotation of the motor, and outputs the motor speed as a digital value based on the duty of the square wave signal. The phase detecting means detects the rotation phase of the motor as a digital value. The speed error calculating means and the phase error calculating means respectively calculate the speed error or the phase error of the motor based on the detection result of the motor speed or the rotation phase. The adder digitally adds the output of the speed error calculator, the output of the phase error calculator, and the output of the disturbance torque observer. The disturbance torque observer estimates the disturbance torque applied to the motor based on the output of the adding means and the output of the speed detecting means, and outputs the estimated torque to the adding means. Further, the output of the speed detecting means passes through the duty unevenness correcting means prior to the input to the disturbance torque observer. The duty unevenness correcting means corrects the duty unevenness of the square wave signal generated by the speed detecting means. As described above, under the configuration in which the output of the adding means, which is a digital value, is input to the observer, there is no need to A / D convert the drive current of the motor or D / A convert the output of the disturbance torque observer. Hardware for A / D conversion and D / A conversion becomes unnecessary, and deterioration of control performance due to time delay caused by the presence of this hardware is avoided. Further, in the configuration in which the output of the speed detecting means is subjected to the duty unevenness correction as described above, even if the square wave signal has the duty unevenness due to the doubling or the like, the duty unevenness is not applied to the disturbance torque estimation. Impact
It is unlikely to occur.

In the second aspect , the correction unit first calculates the average length of the period of the same value included in the square wave signal. The correction unit sequentially subtracts the average length from the time length of the period,
Add the target length for the period. According to the second aspect , the unevenness of the duty is corrected by such a method, so that the variation of the unevenness of the duty is corrected.

[0031] In the third aspect, the phase pull-determining means determines whether or not the phase synchronization pull based on the rotation phase detected by the phase detection means has been made,
Phase error calculation by adding means only when
Add the outputs of the means . Therefore, in claim 3 ,
When the phase lock pull-in is not performed, the output of the external torque observer is not reflected in the control, so that the inaccuracy of the observer output due to, for example, a phase change at the time of startup is excluded from the control. As a result, the phase lock pull-in is speeded up, and once the phase lock pull-in has been performed, the rotation speed fluctuation of the motor is suppressed.

[0032]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. The same components as those in the conventional example shown in FIGS. 16 and 17 are denoted by the same reference numerals, and description thereof will be omitted.

FIG. 1 shows a configuration of a motor control device according to a first embodiment of the present invention, and FIG.
Each is represented. As shown in FIG. 1, in the present embodiment, the drive current I is not taken into the disturbance estimation observer (7), but the added value An is taken. The observer operation value Cn output from the disturbance estimation observer (7) is fed forward to an adder (6) in front of the motor (1) as in the observer operation signal in FIG.
Rather than being de, fed forward to the subsequent addition of the speed error computing section (8) (6). Adder (6)
Does not add the observer control signal to the output of the MDA (5), but the speed error signal Bn and the observer operation value C
n is added, and the added value An is supplied to the disturbance estimating observer (7) in addition to the PWM converter (2). Although FIGS. 1 and 2 do not show an FG section for supplying the angular velocity ω to the disturbance estimation observer (7) and do not show a phase control system, these are assumed to actually exist. I do.

In the block diagram shown in FIG.
The disturbance estimation observer (7) is multiplied by the multipliers (30) and (3).
1) is included. The multiplication unit (30) multiplies the addition value An by a coefficient and supplies the result to the adder (20). The multiplication unit (31) also multiplies the estimation value _TG by the coefficient and obtains the observer operation value C
It is supplied to the adder (6) as n.

The coefficient to be multiplied in the multiplication unit (30) is K _PWM · K _A · K _T · g. In the conventional example shown in FIG. 17, a composite transfer function from the output of the velocity system coefficient section (15) to the multiplication section (19) is obtained as K _PWM ·
H _LPF (s) · K _A · R · F _AD · α · K _T · g, and by substituting α = 1 / (R · F _AD ), K _PWM · H _LPF (s) · K It is transformed to _A · _KT · g. In this embodiment, the cutoff frequency of the LPF (3) is set sufficiently higher than the frequency handled by the motor control system (that is, H is set in the band handled by the disturbance estimation observer (7)).
_By setting _LPF (s) to a cutoff frequency that can be regarded as 1), the control performance of the disturbance estimation observer (7) is not significantly affected. That is, from K _{PWM M} · H _LPF (s) · K _A · K _T · g to H
K _PWM · K _A · K _T · g without _LPF (s) is provided to the multiplication unit (30).

Similarly, as the output destination of the disturbance estimation observer (7) is changed to a stage subsequent to the speed coefficient section (15), the multiplication section (31) includes a coefficient 1 / (K _PWM · K
_A · _{K T)} has been granted. More specifically, as the feed-forward path transfer function of the output of the subtractor (24) in the prior art to the adder (6) are stored, the coefficient multiplier (31) is set.

Next, the operation of this embodiment will be described. FIG. 3 shows the operation of this embodiment.

In this embodiment, the operation of the speed error calculation section (8) is in a waiting state until a rising or falling edge is detected for the FG signal output from the FG section (13) (101). . When an edge is detected, a time difference from the previously detected edge, that is, a cycle of the FG signal is calculated, and a speed error signal Bn is calculated based on this cycle as in the conventional example (102).

On the other hand, the angular velocity ω is taken into the disturbance estimation observer (7) (103). In this embodiment, as in the conventional example, the means for obtaining the period of the FG signal and supplying it to the multipliers (21) and (22) is omitted from FIG. The disturbance estimation observer (7) calculates an estimated value _TG based on the angular velocity ω and the value of the added value An ,
Further, an observer operation value Cn is output (104). Here, except that the modification of the multiplication units (30) and (31) is performed as described above, the step (10) is performed.
The operation of 4) is the same as that of the disturbance estimation observer (7) of the conventional example.

The observer operation value Cn is supplied to the adder (6), and is added to the speed error signal Bn (105).
Therefore, An = Bn + Cn. The added value An obtained as a result is supplied to the PWM converter (2), and the PWM control of the motor (1) is performed accordingly (1).
06). At the same time, the added value An is also supplied to the multiplication unit (30) and used in step (104). Thereafter, the process returns to step (101).

As described above, according to this embodiment, the same basic operation as that of the conventional example can be performed, and the advantages obtained in the conventional example can be enjoyed as before. Further, in this embodiment, an addition value An, which is a digital value, is supplied to the disturbance estimation observer (7) instead of the drive current I, which is an analog value, and the output of the disturbance estimation observer (7) is controlled by the drive current I. Therefore, there is no need for A / D conversion or D / A conversion because the digital amount can be added to the speed control signal Bn. Therefore, the apparatus can be configured in a software manner, and there is no time delay caused by A / D conversion or D / A conversion, and control performance is improved. Specifically, FIG.
Can be softwareized except for the hard part (32) represented by the two-dot chain line in the broken line (29).

In this embodiment, the disturbance estimating observer (7) is a minimum-dimensional observer, but may be of another type, for example, a same-dimensional observer.
Further, the present invention may be applied to an observer such as a speed estimation observer instead of the disturbance estimation observer. Further, not only the drum motor and the capstan motor of the VTR but also other types of motors may be controlled. Furthermore, PWM
Instead of the control, the motor may be controlled by a D / A conversion method or the like.

FIG. 4 shows the configuration of the second embodiment of the present invention. This embodiment is different from the first embodiment in that the motor (1)
In contrast to the configuration in which the current is controlled, the configuration in which the voltage is controlled. In particular, the control method shown in this figure is a method in which a transistor for controlling the voltage of the motor (1) is directly driven by a PWM signal.

In this embodiment, the microcomputer (3
3) is provided. This microcomputer (33)
Monitors the output of the detection means for the angular velocity ω (not shown), controls the speed and phase of the motor (1), and also performs the function of a disturbance estimation observer. Microcomputer (3
The output of 3) is a PWM signal, and this PWM signal is supplied to the transmission block (34).

The transfer block (34) has a transfer function G
_d (s). The transmission block (34) includes the transistors (TR ₁ ), (TR ₂ ), and the transistor (TR).
₂ ) a base resistance (R ₁ ), a transistor (TR ₂ ) base-emitter resistance (R ₂ ), a switching diode (D), a coil (L), and a capacitor (C).

The base of the transistor (TR ₁ ) has P
The WM signal is supplied. Therefore, the transistor (T
R ₁ ) is turned on and off by the PWM signal. Transistor collector of (TR ₁₎ is connected to the base of the transistor (TR _2), therefore, the transistor _(TR 2)
Are also turned on and off by the PWM signal. The coil (L) and the capacitor (C) constitute a filter for converting the switching waveform of the transistor (TR ₂ ) into a direct current, and the cutoff frequency thereof can approximate the transfer function of the filter to 1, as in the first embodiment. It is set high enough.

In this embodiment, the microcomputer (33) functions similarly to the first embodiment. Since the drive current I is determined from the PWM conversion gain K _PWM and the transfer function G _d (s), the estimated value T _G ＾ can be obtained. That is, the same effects as those of the first embodiment can be obtained in this embodiment.

FIG. 5 is a block diagram of a motor control device according to a third embodiment of the present invention. In this embodiment, instead of taking the angular velocity ω from the torque-rotation conversion unit (10) into the disturbance estimation observer (7), the output of the speed detection unit (14) is converted into the conversion unit (35) in the disturbance estimation observer (7). ) Is taken into the multipliers (21) and (22). In this case, the conversion gain α ′ of the conversion unit (35) is the reciprocal of the product of the conversion gains of the FG unit (13) and the speed detection unit (14), that is, α ′ = 2π / (K _FG · H
_F (s)). According to this embodiment, the same operation as that of the first embodiment is performed, and the same effect can be secured.

In this embodiment, the FG section (13) has a structure as shown in FIG. That is, it has a magnetic head (36), a threshold voltage source (37), and a waveform shaping circuit (38). It is assumed that the motor (1) is provided with a magnetized pattern (201) in advance.

The magnetic head (36) of the FG section (13) reads the magnetization pattern (201) and supplies the sine wave signal (a) to the waveform shaping circuit (38). Waveform shaping circuit (38)
Is supplied with a threshold voltage (b) from a threshold voltage source (37) in addition to the sine wave signal (a), and the waveform shaping circuit (38) converts the sine wave signal (a) to the threshold voltage (b). Compare. Then, as shown in FIG. 7, the period when the sine wave signal (a) is larger than the threshold voltage (b) has the H value, the period when the sine wave signal is small is the L value,
An FG signal (c), which is a square wave signal, is obtained. This FG
The signal (c) is supplied to the speed detector (14) and used for speed control and disturbance torque estimation.

In this embodiment, when the threshold voltage (b) is an accurate value (b ₁ ), an FG signal (c) shown as (c ₁ ) in FIG. 7 is obtained. Here, an accurate value of the threshold voltage (b ₁ ) means that such an FG signal (c ₁ ) having an H value period = T / 2 and an L value period = T / 2 and a duty ratio = 50% is obtained. It refers to voltage. T is the period of the sine wave signal (a) and thus the FG signal (c). With such an FG signal (c ₁ ), no control error occurs even if the signal is doubled and used.

However, if the threshold voltage (b ₂ ) deviates from the threshold voltage (b ₁ ), the FG signal (c ₂ ) with a duty ratio of about 50%
Becomes That is, duty unevenness occurs. Even when such an FG signal (c ₂ ) is output from the FG section (13) and speed detection is performed, if speed detection is performed by detecting only the rising edge or falling edge of the FG signal (c), Since the period T is constant, no problem occurs. However, when doubling is performed, that is, when the time between the rising edge and the falling edge is detected and the speed is detected, the uneven duty is reflected in the disturbance torque estimation operation. The rotation fluctuation of the motor (1) occurs.

FIG. 8 is a block diagram of a fourth embodiment in which further attention is paid to such points. This embodiment has a configuration in which a correction unit (39) is added to the third embodiment. The correction unit (39) includes a speed detection unit (1).
4) This member is arranged at the subsequent stage and can be configured by software. Therefore, also in this embodiment, the first
An effect similar to that of the embodiment or the third embodiment can be obtained.

An effect newly obtained in this embodiment is accurate disturbance torque estimation by correcting duty unevenness.
9 and 10 show the operation of this embodiment.
Hereinafter, advantages of the present embodiment will be described through an operation description.

In this embodiment, the FG section (13)
Operates in the same manner as in FIGS. Speed detector (1
4) executes determination (301) on the FG signal (c). This determination (301) is a step of determining whether any of the rising edge and the falling edge of the FG signal (c) has been input. That is, in this embodiment, a doubling operation for detecting a half cycle by inputting both the rising edge and the falling edge is performed. Judgment (3
This determination (301) is repeated until it is determined in step (01) that an input has been made.

If it is determined that the input has been made, the correction section (39) increments the content m of the FG counter by one (302). The FG counter is a counter configured as software or hardware in the processor and used by the correction unit (39), and is initially “0”.
Is set to The content m of the FG counter indicates whether the input edge is a rising edge or a falling edge, as will be understood later.

Next, the speed detection unit (14) calculates the half cycle _{x m} of the FG signal (c) (303). Correction unit (3
9) determines whether the correction calculation flag is “1” (304). The correction calculation flag is a flag indicating whether or not the correction calculation is being performed, and the initial value is “1”. Therefore, it is “1” immediately after the start of the operation, and step (30)
Go to 5).

In step (305), the correction section (39) makes an even / odd judgment on the content m of the FG counter . If m is even, it is immediately after the rising edge input, and if m is odd, it is immediately after the falling edge input .
You. In the case of an even number , the time difference between the currently input rising edge and the previously input falling edge, and conversely, in the case of an odd number , the time difference between the currently input falling edge and the previously input rising edge. but it has been required as a half period _{x m} in each step (303).
Accordingly, step (305) if it is an odd number in a half cycle of the current half-cycle x _m is FG signal (c) is L value, the current half-cycle x _m if it is an even FG
The signal (c) is a half cycle of the H value.

In this embodiment, the correction section (39)
Indicates that the half cycle of the L value and the half cycle of the H value are separately counted. That is, if it is determined that the number is an even number, step (3)
06) is executed, and when it is determined that the number is an odd number, step (307) is executed. In step (306), _{x m} is added to _{x h,} in the step (307), _{x m} is added to _{x l.} Where _xh and _xl
Is initially set to “0”.

These steps (306) and (307)
After the execution of (3), the determination (308) is performed. That is, the correction unit (39) determines whether the addition has been performed a predetermined number of times (n times). If it is determined that the determination has not been made, the process returns to step (301), and the above-described calculation is repeated.

If it is determined in step (308) that the above operation has been repeated to reach n times,
The correction unit (39) executes Step (309). At this time, when the content m of the FG counter is an even number, _xm is x
_h are accumulated in, x _m in the case of an odd number are accumulated in x _l. In step (309), calculation of _{x H = x h / n x} L = x l / n is performed. The x _H and x _L can be understood to be a mean value of the half cycle of the H values and the L values. Thereafter, the correction unit (39) sets the correction flag to “1” (310). Correction flag is initially being set to "0", a flag indicating whether x _H and x _L is required.

Next, the operation moves to the operation shown in FIG. The correction unit (39) determines whether the correction flag is “1” (311). In this case, since the correction flag is “1”, the process proceeds to step (312). The correction unit (39) performs an even / odd determination on the content m of the correction counter in step (312). If the number is even, the process proceeds to step (313). If the number is odd, the process proceeds to step (314).

In step (313), X = x _m -x _H
+ X ₀ is X = x _m −x _L + in step (314).
x ₀ is calculated by the correction unit (39).
Here, x ₀ is an offset value, which represents the true half-period of the FG signal (c). Thus, X obtained in this way is a correction value obtained by correcting the duty unevenness from the detected half cycle x _m. Thereafter, the correction unit (39) sets the correction calculation flag to "0" and ends the correction calculation (31).
5).

Subsequently, the speed system coefficient section (15) calculates a speed error (316), and obtains a disturbance estimation observer (7).
Estimates the disturbance torque _TG (317), the adding unit (6) adds the speed error signal Bn and the observer operation value Cn (318), and the added value Cn is a PWM converter (2).
Is output as a PWM signal (319).

Thereafter, the flow returns to step (301).
Thereafter, the operation up to step (303) is the same as described above, but the process branches to step (311) because the correction calculation flag is "0" in step (304). Further, since the correction flag has already been set to "1", the process proceeds to step (312). If the correction flag is "0", the flow shifts to step (316).

As described above, in this embodiment, even when the edge of the FG signal (c) is detected by doubling,
More accurate disturbance torque estimation by correcting duty unevenness,
As a result, control of the motor (1) can be realized. Further, since the average value is obtained and used for correction, there is no delay in the calculation time.

Note that the duty unevenness correction may be performed by another method. The disturbance estimation observer (7) may be, for example, the same dimension observer instead of the minimum dimension observer, and the disturbance estimation observer (7) may be replaced with a speed estimation observer. May be used. Needless to say, it is not limited to a capstan motor or the like.

Next, a fifth embodiment of the present invention will be described. FIG. 11 is a block diagram of this embodiment.

In this embodiment, the configuration of the phase control system which is omitted in the above-described conventional example and each embodiment is also shown. That is, an integral element (40) for converting the angular velocity ω of the motor (1) into a phase by integrating the output of the torque-rotation converter (10), and the rotation of the motor (1) based on the output of the integral element (40). A phase detector (41) for detecting a phase is shown. In the drawing, H _P (s) is a transfer function of the phase detector (41). The output of the phase detector (41) is supplied to the adder (6), whereby a feedback loop related to phase control is configured.

Further, in FIG. 11, the disturbance torque _TG
The adder (11) relating to the addition of (1) is omitted, and the amplifier (12), which is a block representing the gains of both the amplifier (4) and the motor drive ramp (5), is replaced with an amplifier (42) in transition.
And (43). Amplifying unit (42)
The gain of the amplifier (43) is K _AMP and the gain of the amplifier (43) is K _M
It is designated as _DA . Further, the addition value An output from the addition unit (6) is output to the multiplication unit (3) via the delay unit (44).
0). The delay unit (44) sets the addition value An to 1
This is a delay unit that delays by the sampling period _TF .

In this embodiment, the phase control system operates as follows. In the speed control system described above,
The FG unit (13) generates an FG signal corresponding to the rotation speed of the motor (1) according to the rotation of the motor (1). However, in the phase control system, the PG signal is generated every one rotation of the motor (1). (Pulse Generator) One pulse of the signal is generated, and the time difference from the reference phase is measured. This measurement is based on the integral element (4
0), and subsequently the rotational phase of the motor (1) is detected by the phase detector (41). This rotational transfer is supplied to the PWM converter (2) via the adder (6) and contributes to generation of a PWM signal.

As described above, according to this embodiment, not only the speed control but also the phase control are performed, so that the rotation speed fluctuation of the motor (1) is suppressed.

Further, since the disturbance estimation observer (7) is provided, the rotation speed fluctuation of the motor (1) caused by the disturbance torque _TG is suppressed. Furthermore, A / D conversion and D /
Since there is no need for A-conversion, the present embodiment can provide the same effects as those of the first embodiment.

FIG. 12 shows a configuration of a motor control device according to a sixth embodiment of the present invention. This drawing is a block diagram, in which the same omissions and the like as in FIG. 11 are given. This embodiment is different from the fifth embodiment shown in FIG. 11 in that a phase synchronization pull-in determination means (45) is added.
Further, a changeover switch (46) which is turned on / off by the phase synchronization pull-in determination means (45) includes a multiplication unit (31).
And an adder (6). In this embodiment, the fifth embodiment shown in FIG. 11 is further improved to enable early phase lock-in at the time of transient response such as when starting the motor. That is, the output of the phase detector (41) greatly fluctuates and the speed command value fluctuates greatly during a transient response such as when the motor is started, and as a result, the occurrence of an overflow and the disturbance torque _TG in the calculation process of the disturbance estimation observer (7). May be inaccurately estimated, the speed command value may become an inappropriate value, and the simultaneous phase pull-in may be delayed. In this embodiment, the supply of the estimated value Cn by the disturbance estimating observer (7) to the adding unit (6) under the control of the phase synchronization pull-in determining means (40) at the time of starting the motor (1) or the like is to be refused. Is what you do. FIG. 13 shows a flow of the operation of this embodiment. Note that the speed control, the phase control, and the operation of estimating the disturbance torque _TG are the same as those described above, and thus the details are omitted here.

[0075] The apparatus of this embodiment, with the rotation of the motor (1), to the edge of the edge or P G signal of the FG signal is input, the speed detection and phase detection is not performed. FG
When the edge of the signal is input (401), the step (4)
05) to (410), and then to step (402). Further, when the edge of the PG signal is input while the edge of the FG signal is not input (4
02), execute the operations of steps (403) and (404), and wait for the input of the edge of the FG signal again (401)
Return to

In step (403), the phase is detected by the phase detector (41).
_P is output from the phase detector (41). Phase pull-in discriminating means (45) determines whether the phase detection result phase pull-in based on the N _P have been made (4
04).

On the other hand, if it is determined in step (401) that an edge of the FG signal has been input, steps (405) to (410) are executed. Step (40
In 5), the speed detection unit (14) performs velocity detection, thereby outputting _{N F.} Addition unit (6) adds the phase detection result N _P is the output of the speed detector (14) which is the output speed detection result of the N _F and the phase detector (41), PWM converting the addition result N It is output to the vessel (2) (406). At this time, the phase synchronization pull-in determination means (45)
In step (404), it is determined whether or not phase lock-in has been performed. After step (406), the operation branches in accordance with the result of this determination (407), and the operation result N _O (estimated value Cn) of the disturbance estimation observer (7) is obtained only when the phase lock-in is performed.
Uptake (408) to the adder (6) via a switch (46) switches the corresponding) to further the calculation result of the disturbance estimation observer (7) is added to _{N O} to sum N (409). That is, the phase synchronization pull-in determination means (4
5) determines whether or not the phase pull-in based on the phase detection result N _P is made to turn on the switch (46) switched only when being made, the result calculation by the disturbance estimation observer (7) N _O Is supplied to the adder (6).

[0078] Thus, immediately when after operation result N _O disturbance estimation observer (7) was added to N, or the phase pull-in is switched not yet made the switch (46) has been turned off, step The operation according to (410) is performed. The step (410) shows the (N) PWM conversion operation by the PWM converter (2). As a result, the PWM control of the motor (1) is executed.

As described above, according to the present embodiment, the speed control and the phase control are performed using the output of the disturbance estimation observer (7) only when the phase lock-in is performed. The phase-locking pull-in does not slow down during a transient response such as when the motor (1) is started, and the motor (1) is driven by the disturbance torque _TG.
Disturbance speed fluctuation can be suppressed.

FIG. 14 shows the configuration of a motor control device according to a seventh embodiment of the present invention. This embodiment further simplifies the configuration of the sixth embodiment shown in FIG.
This is to achieve the same effect as in the embodiment more economically. That is, as clearly shown in FIG. 14, a timer (47) is provided instead of the phase lock pull-in determination means (45). This timer (47) is a timer for switching the changeover switch (46) from off to on after a predetermined time has elapsed from the start of the motor (1). Therefore, the operation of this embodiment shown in FIG. 15 also differs from the operation of the sixth embodiment shown in FIG. 13 in that step (404) is omitted and step (407) is replaced with step (411). . That is, in this embodiment, the disturbance estimating observer is used only when it is considered that a certain time has elapsed during the activation of the motor (1) as a result of the operation of the timer (47), not whether or not the phase lock-in has been performed. (7) of the operation result is intended to tackle the _{N O} to the adder (6).
Therefore, according to this embodiment, the effect obtained by the sixth embodiment can be realized with a simpler configuration.

In this embodiment, the motor (1)
Is the starting point of the timer (47).
For example, another transition time such as a mode transition between normal reproduction and special reproduction such as speed search may be used as a reference. Further, the motor is not limited to the drum motor of the VTR, but may be another motor such as a capstan motor.

[0082]

As described above, according to the first aspect of the present invention,
According to the above, the observer monitors the motor based on the digital rotation speed and speed signal output from the speed detection means, and executes the disturbance torque estimation operation.
A / D conversion, D / A conversion, and the like are not required, and effects such as realization of a simplified and economical configuration by omitting hardware, improvement of control performance by preventing occurrence of time delay by A / D conversion, and the like are obtained. .

According to the first aspect of the present invention, since the duty unevenness included in the square wave signal representing the rotation speed of the motor is corrected, the estimation of a variable such as a disturbance torque becomes more accurate.

According to the second aspect , the average value of the rotation frequency of the motor is calculated, and the duty unevenness is corrected based on the average value. The effect that speed detection becomes possible is obtained.

According to the third aspect , since the output of the observer is used for control only when the phase synchronization is performed, the fluctuation of the rotational speed is not reflected in the estimation of the disturbance torque or the like at the time of a transient response such as when the motor is started. In this manner, occurrence of an error can be prevented.

[0086]

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a configuration of a motor control device according to a first embodiment.

FIG. 2 is a block diagram illustrating a configuration of a motor control device according to the first embodiment.

FIG. 3 is a flowchart illustrating a flow of an operation of the motor control device according to the first embodiment.

FIG. 4 is a circuit diagram showing a configuration of a motor control device according to a second embodiment.

FIG. 5 is a block diagram illustrating a configuration of a motor control device according to a third embodiment.

FIG. 6 is a diagram showing a configuration and an operation diagram of an FG unit.

FIG. 7 is a diagram showing a waveform of an FG signal.

FIG. 8 is a block diagram illustrating a configuration of a motor control device according to a fourth embodiment.

FIG. 9 is a flowchart showing a part of the operation of the motor control device according to the fourth embodiment.

FIG. 10 is a flowchart showing a part of the operation of the motor control device according to the fourth embodiment.

FIG. 11 is a block diagram illustrating a configuration of a motor control device according to a fifth embodiment.

FIG. 12 is a block diagram illustrating a configuration of a motor control device according to a sixth embodiment.

FIG. 13 is a flowchart illustrating an operation of the motor control device according to the sixth embodiment.

FIG. 14 is a block diagram illustrating a configuration of a motor control device according to a seventh embodiment.

FIG. 15 is a flowchart illustrating a flow of an operation of the motor control device according to the seventh embodiment.

FIG. 16 is a diagram showing a configuration of a motor control device according to a conventional example.

FIG. 17 is a block diagram showing a configuration of a conventional example.

[Explanation of symbols]

(1) Motor (2) PWM converter (6) Adder (7) Disturbance estimation observer (8) Speed error calculator (9) Current-torque converter (10) Torque-rotation converter (13) FG unit ( 14) Speed detector (20) Adder (21), (22) Multiplier (23) Primary delay element (24) Subtractor (29) Software part (30), (31) Multiplier (33) Microcomputer (36) Magnetic head (37) Threshold voltage source (38) Waveform shaping circuit (39) Correction unit (40) Integral element (41) Phase detector (45) Phase synchronization pull-in determination means (46) Changeover switch (47) Timer I drive current ω motor angular velocity An additional value Bn speed error signal Cn observer calculation value (a) sine wave signal _{(b), (b 1)} , (b 2) Suresshoru Voltage _{(c), (c 1)} , (c 2) FG signal x _{H, x L} average N _P phase detection result N _F speed detection result N sum N _O observer operation result

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-55-141817 (JP, A) JP-A-61-1286 (JP, A) JP-A-63-220786 (JP, A) JP-A 64-64 26385 (JP, A) JP-A-61-266086 (JP, A) JP-A-1-103183 (JP, A) JP-A 1-234079 (JP, A) JP-A-3-293988 (JP, A) JP-A-4-156283 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) H02P 5/00

Claims (3)

(57) [Claims] 1. A drive means for driving a motor in accordance with a control signal of a digital value, a square wave signal generated in accordance with a rotation speed of the motor, and a rotation speed of the motor detected as a digital value based on a duty of the signal. Speed detection means for calculating, a speed error calculation means for calculating a speed error of the motor based on an output of the speed detection means, a phase detection means for detecting a rotation phase of the motor as a digital value, and an output of the phase detection means And a disturbance torque observer for estimating and outputting a disturbance torque applied to the motor as a digital value, based on the output of the speed error calculation means. Adding means for adding the output of the phase error calculating means and the output of the disturbance torque observer as a digital value ; Driving means for driving the motor based on the added output, and duty unevenness correcting means for correcting the duty unevenness of the square wave signal generated by the speed detecting means, wherein the disturbance torque observer has the duty unevenness corrected. estimating a disturbance torque applied to the motor based on the outputs of the adding means of the velocity detecting means
A motor control device that controls the motor based on the addition output . 2. The duty unevenness correcting means includes:
The average length of the period of the same value included in the square wave signal is calculated, the average length is subtracted from the time length of the period at any time, the target length of the period is added, and the duty unevenness is corrected. The motor control device according to claim 1. 3. A phase synchronization pull-in determining means for determining whether or not the rotation phase synchronization of the motor is performed based on the rotation phase detected by the phase detection means, and only when the rotation phase synchronization is performed. 2. The motor control device according to claim 1, wherein the output of the phase error calculating means is added by the adding means.