JPH02193586A - Rotating phase controller - Google Patents

Abstract

PURPOSE:To shorten lock-in time by detecting whether a phase difference between a phase detection signal indicating the rotating phase of a rotor and a reference signal is within a predetermined range or not, and initializing the process of phase compensating means in response to its detection output. CONSTITUTION:Whether a phase difference between a phase detection signal P indicating the rotating phase of a rotor 1 and a reference signal RC is in a predetermined range or not is detected, and the process of phase compensating means 7 is initialized in response to the detection output. Thus, when the rotating phase of the rotor 1 approaches a target phase, the process of the phase compensating means 7 can be initialized, the delay of the process due to the integration of the phase compensating means 7 is removed according to it, and the overshoot of the control target phase of the rotating phase is eliminated. Accordingly, even if a phase control is strongly performed, hunting does not occur.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a rotational phase control device, and particularly to a rotational phase control device that performs phase control by performing at least integral processing on phase error information.

[Prior Art] Conventionally, when configuring a rotational phase control device that controls the rotational phase of a rotating body and rotates it in synchronization with a specific reference phase, the rotational speed is controlled based on rotational speed information obtained from the rotating body. It is common to install a rotation speed control device to perform this. That is, while rotating the rotating body at a speed near the target rotational speed using a rotational speed control device, a phase difference between these is detected based on rotational phase information obtained from the rotating body and reference phase information, and this phase difference information is detected. It is common to control the rotational phase using a phase error signal formed based on

On the other hand, in order to perform such phase control more strongly and stably, a phase compensation circuit that mainly operates as an integrator circuit is provided, and the phase error signal is passed through this phase compensation circuit as a phase control signal to the drive system of the rotating body. It is widely practiced to supply

[Problems to be Solved by the Invention] Incidentally, the integration time constant of the phase compensation circuit may be set relatively large. In this case, stability in a steady state is improved, but there is a problem in response characteristics in a transient state that the control pull-in time (lock-in time) becomes longer.

In particular, when the mixing ratio of the phase control signal to the speed control signal is increased in order to apply stronger phase control, the rotational phase often approaches the target phase after overshooting, and in some cases hunting may occur. This resulted in a significantly longer lock-in time.

The present invention has been made in view of such problems, and provides a rotational phase control device that does not cause phenomena such as hunting even when strong phase control is applied and can shorten lock-in time. The purpose is to

[Means for solving the problems] For this purpose, the rotational phase control device of the present invention has the following features:
Phase error detection means that generates phase error information according to the phase difference between a phase detection signal indicating the rotational phase of the rotating body and a reference signal; and a phase compensation means that performs at least an integral process on the phase error information and outputs it as phase control information. and a phase lock detection means for detecting whether the phase difference is within a predetermined range, and an initialization means for initializing the processing of the compensation means in response to the output of the lock detection means.

[Operation] By configuring as described above, it is possible to initialize the processing of the phase compensation means when the rotational phase of the rotating body approaches the target phase, and accordingly, the processing delay due to the integral processing is removed, and the rotational phase is This eliminates the possibility of overshooting the control target phase.

Therefore, even if strong phase control is applied, no hunting phenomenon occurs, making it possible to shorten the lock-in time.

[Example] Examples of the present invention will be described below.

FIG. 1 is a diagram showing the configuration of an embodiment in which the present invention is applied to a rotary cylinder control system of a VTR, and FIG. 2 is a timing chart for explaining the operation of FIG. 1.

In FIG. 1, 1 is a drum motor that rotationally drives the rotating upper cylinder of the VTR, 2 is a rotational frequency detector that generates a speed detection pulse (FG) with a frequency proportional to the rotational speed of the drum motor 1, and 3 is a rotational frequency detector that generates a speed detection pulse (FG) with a frequency proportional to the rotational speed of the drum motor 1. A rotational phase detector 4 generates a pulse (PG) indicating the rotational phase of the drum motor 1, and a speed detector 4 outputs speed control information (ES) according to the difference between the rotational speed of the drum motor 1 and the target speed using an FG. 5 is a reference signal generator that generates a reference signal (RC) indicating the reference phase; 6 is phase difference information (PD) indicating the phase difference between the reference signal and the PG; and phase error information (PE) corresponding to this phase difference.
), 7 is a digital filter that acts as a phase compensation circuit, and 8 is a phase detection circuit that outputs the phase control information (EP) output from the digital filter and the above-mentioned flight control information (
9 is an adder that adds data (ES) to form rotation control information (CT), and 9 is an adder that adds data (
Preset data (P
10 is a digital-to-analog (D/A) converter, 11 is a drive circuit that drives the drum motor 1, and 12 is a drive circuit that controls the operation of the drive circuit 11 and the preset of the digital filter. The control circuit 13 is the operation section of the VTR.

FIG. 2 is a timing chart for explaining the operation of the phase detection circuit 6 shown in FIG. 1. The phase detection circuit 6 uses a PG to generate digital data corresponding to a trapezoidal wave as shown in FIG. . This data TR is sampled at the rising timing of the reference signal RC (indicated by S in the figure).
This becomes phase error information PE. The purpose of this phase control is to make the timing at which the trapezoidal wave data TR reaches a predetermined value (indicated by Po in the figure) and the sampling timing S to be the same timing, and S approaches the illustrated So. The circuit 6 also connects the point P of the trapezoidal wave data TR and the point 3 of the reference signal RC.
The time difference with the point is output as phase difference information PD.

The operation of this embodiment will be explained below.

In the initial state, the drum motor l is stopped. The speed detection circuit 4 increases the value of the speed control information ES as the period of FG becomes longer, so the speed detection circuit 4 increases the value of the speed control information ES according to the information ES.
Although the value of T is also large, the control circuit 12 keeps the drive circuit 11 in a non-energized state. When the operation unit 13 instructs the VTR to record or reproduce a signal, the control circuit 12 enables the drive circuit 11 to be energized, and thereafter the drum motor 1 is driven in accordance with the rotation control information CT.

After the drum motor l is started, when it is accelerated to near the target rotation speed, the reference signal RC is activated by the action of the phase control information EP.
The phase of PG moves from the phase shown by the solid line to the phase shown by the dotted line in FIG. 2 relative to PG. When the control circuit 12 determines using the phase difference information PD that the timing S of the reference signal RC and the timing P0 of the trapezoidal wave data TR match, the control circuit 12 presets the data of each delay technique of the digital filter. Preset with data PR. That is, the control circuit 12 supplies a pulse for loading preset data into the digital filter.

As a result, the timing S of the reference signal RC and the timing P of the trapezoidal wave data TR. When they match, the movement of the relative phase difference stops, and then fine phase control is performed by the output of the initialized digital filter.

As a result, even when the gain of the phase control information EP relative to the phase difference information PD is set large to apply strong phase control, a hunting phenomenon does not occur and the phase control pull-in state is quickly achieved. Moreover, since the integration time constant of the digital filter can be made sufficiently large in a steady state, stable phase control is possible.

- Once the steady state is reached, the digital filter 7 is not initialized if the three points of the reference signal are within the timing between points P and -P of the trapezoidal wave data. However, if the three points of the reference signal once go out of the range of points 21 to 17 of the trapezoidal wave data, and the timing of the three points coincides with the 20th point of the trapezoidal wave data again, the control circuit 12 Detect and initialize the digital filter.

Although a digital filter is used as the phase compensation circuit in the above embodiment, it is also possible to use an analog filter whose center voltage can be preset. Of course, in this case, the phase error information PE is an analog signal. Furthermore, in the above embodiment, if the digital filter 7 is repeatedly initialized during acceleration after the drum motor 1 is started, it is almost equivalent to not performing phase control during this period, and the speed control system is You can start up faster.

Furthermore, in the above embodiment, the initialization timing of the digital filter is set such that the three points of the reference signal RC correspond to the 20th point of the trapezoidal wave data TR.
Although the timing coincides with the point, it is also possible to set a predetermined range of the P0 range and detect when the three points of RC fall within this range. In addition, the slope (rate of data change) of the trapezoidal wave data TR can be set freely, and P
The period between points I and P2 can be freely set.

Processing of control information of the rotation control device configured as described above can be realized by software using a processor such as a microcomputer. In particular, in a device that monitors the rotational control status and changes the information processing characteristics as in the above embodiment, the hardware tends to be large, so it is advantageous to perform most of the processing of the control system in software. It is.

For example, in FIG. 1, the parts indicated by the dotted chain line X and the part indicated by the broken line Y can be replaced by a microcomputer and processed by software.

FIG. 3 is a flowchart illustrating the operation of the computer when the area indicated by the broken line Y in FIG. 1 is replaced by a microcomputer.

The recording or playback start/stop signal (S/
S) is input (step St), steps 82-
In S6, a transition is made to a processing standby state in which human power for each signal is waited for.

In this state, every time the internal clock in the microcomputer is generated (step S2), the time information T is updated (step S7).

Also, every time the FG is manually operated from the rotational frequency detector 2 (
In step S3) and steps 58 to S12, the output control information CT is updated in conjunction with the update of the speed control information ES.

This operation will be briefly explained below.

First, the time T when the FG was manually inputted is set in the variable TR indicating the current FG's manual input time (Step 8), the input time TP of the previous FG is subtracted from this variable TR, the time difference between these is calculated, and the time difference information TE is calculated. (Step S9). Since the speed control information ES is given as a function Fs of this time difference information TE, F, (TE) is assigned to ES (step 510). However, when performing processing corresponding to a loop filter for speed control, F and (TE) may be accumulated for a predetermined period as speed error information SE, and ES may be obtained by calculating this. Then, the updated ES and phase control information EP are added to update the output control information CT (step 511
). Thereafter, the current FG input time TR is set as the previous FG input time in TP (step 12), and the process returns to the processing standby state.

In the processing standby state, the rising edge of PG is detected by rotational phase detector 3.
When the time T is entered manually (step 4), the time T is set in the variable TG in step 13. When the rising edge of the reference signal Re is input from the reference signal generator 5 (step 5), the output control information CT is updated in accordance with the update of the phase control information EP in steps 314 to S23.

The operation will be explained below.

First, the manual time of the rising edge of RC is set to TC (Step 514), the manual time of the rising edge of the immediately preceding PG is subtracted from this time TC, and the current phase difference information PD (
t) is obtained (step 15). Furthermore, current phase error information PE (t) is obtained by processing PD (t) with a predetermined function FP (step 16). This PE(t)
is equivalent to the information supplied from the phase detection circuit 6 to the digital filter 7 in FIG.

Here, it is determined in step S17, 318 whether or not to initialize the phase compensation process.

PTHI and PTH2 are constants, and PTH1<PT
It is H2. That is, the current phase difference information PD (t) is PTH
1 to PTH2, and the previous phase difference information PD(t-
It is determined that 1) is not between PTH1 and PTH2. In other words, the range close to the target phase difference information px is defined as PTH1 to PTH2, and it is determined that the phase difference has been drawn into this range, and if the phase compensation is initialized at this time, the first The same effect as the embodiment shown in the figure can be obtained.

Therefore, when the above judgment is made, preset data PR is assigned to the past n phase error information PE (t-1) to PE (t-n) and the current phase error information PE (t) (step 19). Since the 0 phase compensation process is given as these functions Fi, EP=F i (PE (
t) to PE (tn)), the phase control information EP is updated (step 20). Here, PE (t) to PE (t-n) are preset data P
If R, the phase compensation process is initialized.

Next, speed control information ES is added to this updated phase control information EP to obtain updated output control information CT (
Step 21). And finally, p E (t) ~
Shift P E (t +1- n ) one by one to obtain PE
(t −1) ~ PE (t−n) and step 522) PD(t) is assigned to PD(t−H) and (
S23) Return to processing standby state.

In the processing standby state, when a stop of recording or playback is given as an S/S input from the operation unit 13 (step S6
), the output control information CT is immediately set to 0, and the rotation of the motor 1 is stopped.

Even in software processing using a microcomputer as described above, the same effects as in the apparatus shown in FIG. 1 can be obtained.

[Effects of the Invention] As described above, according to the present invention, there is provided a rotational phase control device that can quickly shift to a control pull-in state even when phase control is strongly applied, and that operates stably even in a steady state. It will be done.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing the configuration of an embodiment in which the present invention is applied to a rotating cylinder control system of a VTR, Fig. 2 is a timing chart for explaining the operation of Fig. 1, and Fig. 3 is the same as that of Fig. 1. It is a flowchart showing the operation when the processing within the broken line part is performed by software processing of a microcomputer. 1 is a motor, 3 is a rotational phase detector, 5 is a reference signal generator, 6 is a phase detection circuit, 7 is a digital filter that performs phase compensation, 8 is an adder, 9 is a preset data generator, 1
1 is a drive circuit, and 12 is a control circuit.

Claims (3)

[Claims] (1) Phase error detection means for generating phase error information according to the phase difference between a phase detection signal indicating the rotational phase of the rotating body and a reference signal, and performing at least an integral process on the phase error information and outputting it as phase control information. A rotation device comprising a phase compensation means, a phase lock detection means for detecting whether the phase difference is within a predetermined range, and an initialization means for initializing processing of the compensation means in response to an output of the lock detection means. Phase control device. (2) The compensation means includes a digital filter, and the initialization means presets each delay branch output of the digital filter.
) The rotational phase control device described in item 2. (3) The rotational phase control device according to claim (1), wherein the compensation means, the lock detection means, and the initialization means are implemented by processing of the same processor. .