JPS58141691A - Controller for rotary drive - Google Patents

Abstract

PURPOSE:To obtain a stable and accurate rotating motion of an article to be rotated by varying the field current by detecting the difference of rotating speed between motors and eliminating the speed difference between the motors. CONSTITUTION:Rotating speed difference between motors 4a and 4b of two systems is detected by a speed difference detector 9, and speed control signal of different signs (positive or negative) is fed to field current controllers 6a, 6b. In other words, a positive speed control signal is fed to the field current controller of the motor which rotates at a high speed, and a negative speed control signal is fed to the field current controller of the motor which rotates at a low speed, thereby eliminating the speed difference between the motors 4a and 4b.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides, for example, a rotating object such as an antenna reflector,
The present invention relates to a rotational drive control device that performs rotational drive by simultaneous driving by multiple series of power transmission mechanisms.

Normally, when rotating an object to be rotated with a large amount of X, such as an antenna reflector, a large driving torque is required, and due to the size and shape of the object to be rotated, Since it is not possible to dispose a driving section above, for example, driving sections r'L are provided at both ends and the driving sections are rotationally driven by a plurality of series of power transmission mechanisms.

Figure 1 shows this type of conventional rotary drive control device.
In the figure, (1) is a two-line power transmission structure, that is, two electric machines (4a) and (4b) connected in series.
The antenna reflector (1) is driven by the rotating torque of the gear box (3aJ*(3bJ) and the binion gear (2aJ, (2b)). The electric motor (4aJ The magnetic field 'magnetic current and i
! Shinko current is controlled.

Therefore, s (5aJ * (5bJ is the motor 4a written in nm)? (41)) is directly connected to the NFC tacho generator, (γ) is the tacho generator (5a) s (5b)
The sum of the detected voltage values of the detected rotational speeds is used as a speed feedback signal, the difference from the speed command signal set in advance is calculated, and based on the comparison value, the companion control signal is adjusted to the armature current. ll
i'114R circuit (8).

In the configuration shown in Figure 1 above, two □' turtle engines (4a
4bJ is generally a shunt coil with a one-turn characteristic, and a constant rated field current is supplied from the field current control circuit C6a)*C6b). Also, Electric Renku.

(4b) are connected in series, so that the same current flows as the armature current output from the armature current control circuit (8). Therefore, the driving torques of the electric motors (4a) and (4b) determined by the field current and armature current are also the same. Therefore, the driving torques of these electric motors (4a) and (4b) are Through gear #1 (3a,)t (3b) and binion gear (2ac (211)e), the antenna reflector (
The n1 antenna reflection @(1) that is simultaneously transmitted to 1) is driven to rotate at a predetermined speed around the rotation axis by a torque that is twice the driving torque for a single electric motor.

During the rotation of the antenna reflector (1), the tacho generators (5a, 5b) are
.

(4b) is detected, and a voltage signal 7 is output to the speed control circuit (7) according to this, and the speed control tgl
@(7), the value of the sum of these voltage signals is expressed as electric m machine (4
vinegar.

(4b) is regarded as speed feedback No. 1g indicating the rotational speed,
Detects the difference from the speed command signal set internally in advance.

Then, based on this detected value, the antenna reflector (1)
Servo compensation is performed to stably drive the motor, a speed difference signal is obtained, and a core signal is output to the armature current control circuit (8). The tMA child current control circuit (8) amplifies the power of this speed error signal and controls the armature current of the motor (4a and 4b).

The armature current flowing through (4b) is controlled by n1 motor a CA
&).

The rotational speed of (4b) is controlled according to the speed command signal.

Conventional rotational drive control devices are configured to rotationally drive the rotated object with the same torque from two series of power transmission mechanisms as described above, so problems arise when there is a difference between the torques of the two series. . That is, the characteristics between two series of electric motors, gear boxes or binion gears, such as output torque characteristics,
If the moment of inertia, spring constant, etc. are different, or if the friction torque between the two train trains changes, the speed of each TA machine will change and become different. As a result, between the two train motors, %8M is the electric engine imaging frequency, K is the spring constant when the gear box, reflector support, etc. between two series of electric motors is used as a spring system, and J is the spring constant of one series of electric motors, gear boxes, etc. The antenna reflector is excited by vibrations at a frequency ω (indicating the moment of inertia), and the antenna reflector rotates without interruption.In other words, stable precision and low-speed drive performance are maintained.
There was a drawback that there was no

The present invention has been made in order to eliminate the drawbacks of the conventional device as described above, and it further detects the difference in speed that causes the vibration state of two series of TS bonds, and calculates the detected value. Based on the positive and negative different speed feedback signals gold each turtle, 41I
Field a1 current control of fI&--A speed difference detection circuit input to the sweetfish is provided to control the field 1iLf/l to each basket fIh machine, and there is no speed difference between the motors, thereby suppressing vibration. It is an object of the present invention to provide a rotational drive control device having the following configuration.

Hereinafter, one embodiment of the rotational drive control device according to the present invention will be described in a second embodiment in which the same or corresponding parts as in FIG.
This will be explained based on 1. In Figure 2, the new code (9) is the two series of e-mails (4a) and (4b).
The field at flow control circuit (6aJ
# (6b) is a speed difference detection circuit that sends out speed control signals with different positive and negative signs, that is, a speed control signal with a positive sign is sent to the field current control circuit of a motor rotating at high speed. At the same time, a negative-sign speed control signal is sent to the field current control circuit of the motor rotating at low speed. Add the Im number to each field current control IEJ path (6a), (6b,) IC input L, and each rated field wt current command value, and then calculate the output to each motor (4a), (4b). It controls the field current to eliminate speed differences between motors and suppress vibrations.

Next, the operation in the configuration shown in FIG. 2 will be explained. Generally, the rotational speed N when the st motor voltage is applied and the motor is rotated is expressed by n. However, ■ is the terminal voltage, Ra is the armature resistance, 1 is the current, k is the constant, and I.

denote the field current, respectively. From this (phantom formula), it can be seen that the rotational speed of the electric motor is inversely proportional to the field current in the vicinity of the rated field current, if the terminal voltage V and armature current are kept constant. The present invention focuses on this point and controls the rotational speeds of the electric motors wk (4a) and (4b) using the field current If.

Currently, the electric motors (4a) and (4b) are in a state of vibration,
Electric motor (4a) is n-engine” Ill + n MdoωM
rotates at a rotational speed of t, while the electric motor (4b)
+1 = “-” M Sin (al w t(7)
Suppose it is rotating at a rotational speed. However, n indicates the average value of the rotational speeds of both military engines, and since the magnitude twice this value is compared and controlled with the speed command value in the speed control circuit (7), it is constant. In addition, nu torture ωMt is the electric motor (4a)
, (4b) indicates the magnitude of the deviation from the average value n of the rotational speed.

In this case, the tachogenerators (5a) and (5b) each have a rotational speed of 1 s of the electric motors (4a) and (4b).
A voltage proportional to nl is generated and output to the speed difference detection circuit (9). In response to this, the speed difference detection circuit (9) detects the difference n□− between the two rotations M degrees according to the difference between the two voltages.
ns=2”Mm6jMt Speed difference signal αnMthωM that is amplified according to K and to obtain the required control accuracy
1 (where α is a proportionality constant) is output to the field current control (b) path (6a), (61)) 0 In this case, the field current of the motor (4a) with a high rotational speed is controlled. The field current control circuit (6a) includes a speed difference signal αnMS
A positive signal IrIωMt is sent to the other field current control circuit (6b), and a negative speed difference signal αnMshIω,1 is sent to the other field current control circuit (6b). Therefore, the field current control circuit (6a) outputs a speed difference signal anM to the rated field current "fR".
Add sfnωM1 and get □ = tR + αnM
dna+Mt; Sends the field current to the electric motor (4a), and on the other hand, the field current control circuit (6b) adds the speed difference signal -anM like 1t to the rated field current "fH,"
1. = Engineering, R-αh-ωM1 The field current is sent to the electric motor (4b), and the electric motor (4a).

Control is performed to eliminate the speed difference between (4b) and (4b).

Then, as mentioned above, while operating at the rated field current xfR,
Speed difference between motors (4a) and (4b): 2 n M m
0M t, each electric motor (4a) or t
t (4b) respectively as the field current Xt, "I."a
n Mg1flllll M” and engineering =E −
When controlled by αnM−ωM1, 6 electric currents 12
fR Explain that the rotational speed of the motive force becomes equal.

First, both military motivations (4a) * (4b) are
Considering the case where kIm flow rate fR is input, the electric motor (4
The terminal voltage of a) is V, and the terminal voltage of motor (4b) is v.
2, the rotational speed of each electric motor can be expressed as n□+JIfi, and when both sides of equations (8) and (4) are added, the following is obtained. In this equation (6), 2n is the speed control circuit (
Since it is controlled by 7), it is one leg, and the armature current xa and field current fR are kept at one leg, so V, +V, = constant = 2Vo... can be said to be arrogant (6) . However, vo indicates a constant value.

Next, electric * (4a), (4b) cv each F[ii
T flow 1. □II.

Assume that the motors (4a) and (41)) are controlled by the difference in rotational speed between them as described above, and the speed and terminal voltage of each motor are calculated as ``'l + n%H''.
V/l, V/.

Then, the following relationship holds true: Even in this case, the sum of the respective speeds of the motors (4a) and (4b) is controlled by the speed control circuit (7), so n ′l+ n ′2 = 2 n = constant −
--(9'1, therefore two electric motors (4a),
The sum of the terminal voltages in (4b) is also v'l + V'2 = 2V = constant --- (10
) satisfies the relationship. Here, the above (') * (7
), (a).

From (9) and the shouting formula, finding the relationship between the speed n/i,... and n%...fist (11J n',=n'1I=n).From this α sword formula, the boiling motor's It can be seen that by controlling the field current using the speed difference between the motors, the rotational speed of each motor becomes equal and constant.As a result, it is possible to suppress the vibrations caused between the motors. It can be done.

In the above embodiment, there are two electric motors, but even if any number of electric motors are connected with a clearance 1j,
Furthermore, it is clear that similar effects can be obtained even if the drive sections of the present invention are used separately depending on the rotational direction of the rotated body in order to eliminate backlash of the drive sections. Historically, it has been clear that even if the characteristics of the motors are different, the same effect can be achieved by changing the control constant of the field current of each motor.

As described above, according to the present invention, the speed difference detection circuit that detects the difference in rotational speed between electric motors and changes the field current is installed in the conventional device, thereby eliminating the difference in speed between the electric motors. ,
This has the effect that vibration between the electric motors can be suppressed, and as a result, stable and highly precise rotational movement of the rotated body can be obtained. Further, since the vibration suppressing means has a very simple structure, it is inexpensive, and since vibrations are suppressed, high reliability can also be obtained.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a conventional rotational drive control device;
FIG. 2 is a block diagram showing a rotational drive control device according to an embodiment of the present invention. (1)...Antenna reflector (2a), (2b)...Binion gear (3a), (
30) -- Gear box (4a), (4b) -- Electric motor (5a), (51))... Tacho generator (6a),
(6m))...Field current control circuit (7)...Speed control circuit ta+...Armature current control circuit (9)...Speed difference detection circuit Note that the same symbols in the diagrams indicate the same or equivalent parts. show. Agent Shin Kuzuno - Figure 1

Claims (1)

[Claims] A power transmission mechanism is installed in each of the power transmission mechanisms that rotationally drives a rotated body by simultaneous driving of a plurality of power transmission mechanisms, and is connected in series with each motor of each ft7 IC series.
- A field current control circuit for each Hrt1 series and an armature current control circuit common to the plurality of series are provided, and speed detection means for each series for detecting the rotational speed of each of the electric motors;
The speed control circuit calculates the sum of the detected values from the speed detector, compares the sum with a predetermined NFC setting value, and applies control No. 1g to the distribution machine current control circuit based on the comparison difference. - In the rotary drive control device configured to commonly control the armature currents of the respective series, each detection output from the speed detection means for each series is inputted to determine the rotational speed difference between each motor, and the rotational speed difference between each motor is determined. Based on the rotational speed difference, a speed control signal with a positive sign is sent to the field current control circuit of the motor rotating at high speed, and a speed control signal with a positive sign is sent to the field current control circuit of the motor rotating at low speed. is provided with a speed difference detection circuit that sends out a speed control signal with a negative sign, thereby eliminating the rotational speed difference between the electric engines and preventing vibrations caused between the electric motors. Rotary drive control device with all features.