SU1167689A1 - Device for controlling step motor in self-communication mode - Google Patents

Abstract

A DEVICE FOR CONTROLLING A STEP ENGINE IN SELF-COMMUNICATION MODE, containing an engine rotor position sensor, power amplifiers, each of which is connected by an output to an engine phase, a distributor, a pulse divider, connected. an input with an output of the pulse generator, and a block for selecting the phase shift of the pulses of the generator relative to the pulses of the position sensor, characterized in that, in order to expand the control range and improve the accuracy of speed stabilization, the block for the selection of the phase shift of the pulses of the generator relative to the pulses of the position sensor is made as a channel switch a control / -5-trigger and a comparison trigger by the number of motor phases connected by the outputs, which are the outputs of the phase shift extractor, to the input m power amplifiers, the first installation inputs to the outputs of the pulse distributor and the address inputs of the channel switch connected to the second installation inputs of comparison triggers and information inputs (L mi to the outputs of the position sensor, the rotor, and the control inputs to the outputs of the control / -5 flip-flop connected to / from one of the rotor position sensor outputs. О: 1 О) 00 со

Description

The invention relates to electrical engineering and can be used in automatic control systems with stepper motors.

The purpose of the invention is to expand the range of regulation and improve the accuracy of stabilizing speed.

FIG. 1 shows a functional diagram of the device; in fig. 2 is a functional diagram of the EMF extraction unit of the turn used as one channel of the rotor position sensor; in fig. 3 - timing diagrams illustrating the operation of the device.

The device (Fig. 1) contains a stepper motor 1 with phases 1.1, 1.2, 1.3, 1.4 connected to the outputs of power amplifiers 2, 3, 4 and 5, respectively, a controlled frequency generator 6, the output of which is connected to the pulse distributor 7, a position sensor motor rotor, made in the form of blocks of 8, 9, 10 and 11 emulsions of vrasheni, and block 12 of the separation of the phase shift of the generator pulses relative to the pulses of the position sensor, consisting of control triggers 13, 14, 15 and 16 of the control / -5-trigger 17 and switch channels 18.

The 5-flip-flop input 17 is connected to the start-up bus of the device 19, the R input is connected to one of the outputs of the position sensor, which includes the EMF spin-off units according to the number of phases of the engine (in Fig. 1, the R input is connected to the EMF release unit - pos.9).

The outputs of the trigger 17 are connected to the control inputs Vx, Vy of the switch 18 channels connected by address inputs X |, X2, Xs, X4 to the outputs of the pulse distributor 7, the information inputs y and Y2, UZ, U4 to the outputs of the EMF units of rotation 8, 9 , 10, 11, and outputs to the second setup inputs of comparison trigger 13, 14, 15, and 16, connected by the first installation inputs to the outputs of pulse distributor 7. The outputs of comparison trigger 13-16 are connected to the inputs of power amplifiers 2-5.

As the rotor position sensor in the device, the units of emf rotation on the number of phases of the engine 8-11 carrying information about the position of the rotor of the engine are used.

Each spinning emf separation unit (Fig. 2) contains a detector 20 connected to the phase of the stepper motor 1, a resistor 21 and a comparator 22, the first input of which is connected to the detector 20 and the resistor 21. A reference voltage source 23 is connected to the second input of the comparator 22.

The device works as follows.

To test the programmable movement along the splint 19, the command "Start (Fig. 3)" in the form of a pulse signal is given. The r5-flip-flop 17 switches to one state and switches the switch 18 to pass the pulse train from the pulse distributor 7 to the first setup inputs of the flip-flops 13-16, the second setup inputs of which receive pulses from the pulse distributor 7 with a shift by one period

input pulses of the generator 6. To the input of power amplifiers 2-5, pulses are generated, formed by triggers 13-16. As a result, the forced switching of the engine 1 is organized.

The rotor of the motor 1 generates signals for the emf of rotation, which are formed by the allocation units 8-11, and are fed to the first inputs of the switch 18. After detection by the detector 20, the signal for the emf of rotation from the phase of the engine I is released on the resistor 21.

The reference voltage source 23 determines the level of formation of the feedback signal at the rotor position from the rotational emf signal, taking into account the load characteristic, which is generated using the comparator 22. One of the signals of the rotational emf emission unit, for example, block 9, is fed to the second setup input / - 5-trigger 17 and sets it to its original state. By launching

5, synchronized with the operation of the pulse distributor 7, the trigger 17 switches the switch 18 to the mode of passing signals from blocks 8-11 to the first installation input of the trigger 13-16. From this point on, engine 1 goes to mode

0 self-switching according to the rotor position signal, formed from the signals of the emf of rotation. In this case, the leading edge of the control pulses applied to the phases of the engine is caused by the moment of formation of the signals for the emf of rotation, and the rear front

 the pulses of the pulse distributor 7. The frequency of the generator 6 sets the phase shift rate of the engine 1. The device starts up from any Frequency within the frequency range of the engine.

0 Further operation of the device occurs in the mode of self-switching when the generator frequency changes from zero to a frequency determined by the boundary of the mechanical characteristic of the engine. The operation of the device is illustrated by time diagrams.

5 (Fig. 3), on which the following signals are given: G - at the output of the pulse generator 6, RI1 ... RI4 - at the output of the pulse distributor 7, "Start - on the bus of the command" Start 19, "Start - on The output of the / -S-flip-flop 17, F1 ... F4- on the phases of engine 1 with two abrupt changes in the control frequency. The point Z in the diagram denotes the moment of formation of feedback signals from the signals of the emf of rotation.

5 From FIG. 3 diagrams it follows that the effect of stabilizing the motor speed around a predetermined value with frequency control in the self-switching mode is achieved by smoothly varying the switching angle and the duration of the control pulses. At the same time, with a change in the frequency of the input pulses in the high-frequency region, the paired commutation switches to an alternate one, which increases the speed of the device by decreasing the self-damping of the engine.

In the proposed device, which can work with any multi-phase position sensor, the EMF rotation sensor, which functions as a position sensor, is used to reduce the drive inertia and simplify the mechanism.

The simplest EMF of rotation is released after de-energizing the motor winding. The moment of de-energizing the winding is directly related to the moment of release of the emf of rotation.

As the timing diagram of FIG. 3, the detector 20 emits, after disconnecting the voltage on the winding, in addition to the emf of rotation, the emf of self-induction, the amplitude of which far exceeds the maximum amplitude of the emf of rotation. The duration of the decay process of self-induction emf is determined by the constant time To Lo / Rf, where LO is

the constant component of the inductance and mutual inductance of the phase circuits; total circuit resistance phase (f)).

The gating of the comparator 22 by pulses of the generator 6, having a duration, makes it possible to get rid of the harmful signal of self-induction EMF when forming the signal of the EMF of rotation, increasing the reliability of the selection of the latter.

The proposed device allows to expand the frequency range of stabilization of the motor speed in the self-switching mode due to the formation of the motor phase switching pulses using triggers controlled by one input from the pulse distributor, and through the second input - from the EMF rotation separating units. Thus, the device allows the motor to be controlled in the mode of self-switching, to stabilize its speed at the level of specified values and has a rather rigid mechanical characteristic.

In addition, the device achieves increased noise immunity by suppressing the emf of self-induction in the spinning emf separation unit.

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Claims (1)

DEVICE FOR CONTROLLING A STEEP MOTOR IN SELF-COMMUTATION MODE, containing a motor rotor position sensor, power amplifiers, each of which is connected to the motor phase by an output, and a pulse distributor connected. an input with an output of a pulse generator, and a unit for extracting a phase shift of the generator pulses with respect to the position sensor pulses, characterized in that, in order to expand the control range and improve the speed stabilization accuracy, the unit for allocating a phase shift of the generator pulses with respect to the position sensor pulses is made in the form of a channel switch, control / iS-trigger and comparison triggers by the number of motor phases connected by the outputs that are the outputs of the phase shift highlighting unit to the inputs of the force teley power the first setting inputs - outputs to the address inputs of pulses and the switch channels connected _with the distributor vyhoda- E with the second setting inputs S trig- Gere comparison, data inputs - outputs from the position sensor, rotor, and control inputs - outputs from the control / iS-trigger connected to the R input with one of the outputs of the rotor position sensor. SU „„ 1167689 Step 1