SU1023614A1 - Device for control of stepping electric motor - Google Patents

Abstract

CONTROL DEVICE CONTROL UNIT 1 1 AGO GM ELECTRIC MOTOR, contains in the pulse distributor and multichannel amplifier ms dnost each. The channel of which includes a key element with a motor phase current control unit and a code analog converter with an input current level register, which is so that, in order to improve energy performance, into the phase current control unit an RS trigger is entered, a delay element with a delay code register and AND elements connected by its first inputs to the outputs of the current level register, output to the code analogue converter inputs, and second inputs to the trigger output connected by input R with the output of the distribution Ithel and input - with the output of the delay element is connected to its control input to the output phase current control unit of the engine.

Description

The invention relates to electrical engineering, namely to an electric drive with a stepper motor, and can be used in digital control systems for machine tools. A device for controlling a stepper motor is known, which contains a pulse distributor and a multichannel power amplifier, each channel of which includes a control unit with a motor phase control unit tl3 ". The disadvantage of this device is the impossibility of changing the current in the phases of the engine during operation, which impairs the drive energy performance. The closest in technical essence to the present invention is a device for controlling a stepper motor, comprising a pulse distributor and a multi-channel power amplifier, each channel of which includes a key element with a motor phase current control unit and a code analog converter with an input register of current level C2. A disadvantage of said device The program of current regulation in the motor phases is hard, which cannot be changed when changing from one mode of operation to another, which also leads to to the deterioration of the energy performance of the drive. The purpose of the invention is to improve the geological characteristics. This goal is achieved by introducing an RS flip-flop into the motor phase current control unit, a delay element with a delay code register and AND elements connected by their first inputs to the current level register outputs, outputs to the code-analog converter inputs, and BTopbiNM inputs - to the output of the trigger connected by the R gate with the output of the distributor, and the S input with the output of the delay element connected by its control input to the output of the motor phase current control unit. Such an embodiment of the device makes it possible to control the torque developed by the engine and, accordingly, the consumption of energy consumed by the engine, i.e. improve drive power characteristics. FIG. 1 is a functional diagram of a device for controlling an electric stepper motor; FIG. 2 - time diagrams of signals on the circuit elements; The device (Fig. 1) contains a high-voltage source 1 connected via a controlled switch 2 with a phase 3 stepper motor and a discharge current shaping unit 4. The other end of phase 3 is connected to shunt 5 and the motor phase current control unit including a comparator 7, connected by the output to the input B of the adder 8, the control input of the programmable delay element 9 and one of the inputs of the element 10. The output of the adder 8 is connected to the direct input of the comparator 7. The input B of the adder C is connected to the output of the converter code 11, inputs of which oedineny register 12 with the outputs connected to inputs of a computer program or device. The input A of the adder 8 is connected to the output of the converter code-analogue 13, the inputs of which are connected to the outputs of the elements 14. And some of the inputs of the elements 14 are connected to the outputs of the register 15 connected by inputs to the computer, and the others are interconnected and connected are connected with a single output of the trigger 16, the input R of which is connected to the output of the distributor (not shown), another input of the element I 10 and the control input of the control unit 4 of the discharge current of the motor phase. The input S of the trigger 16 is connected to the output of the delay element 9, the inputs of which are connected to the outputs of the register of the delay code 17, also connected by inputs to the computer. The device works as follows. In the initial state, the output of the distributor receives a logical zero signal, which locks the element 10, which ensures that the phase 3 of the stepping motor is disconnected from the power source 1 by the locked key element 2. At the inverse input of the comparator 7, the voltage is zero A voltage Uy ,, is applied to the direct input of the comparator 7 (Fig. 2). For example The value of U at the direct input of the comparator 7 is always defined by the formula II -HilHiiHs p- where U | - the voltage at the output of the code converter kodalog 13, the voltage at the output of the converter code analogue 11, the voltage at the output of the comparator g is the transfer coefficient of the adder. When a logical unit receives a signal from the distributor, the trigger 1 16 is set to the position where the signal of the logical unit from its output goes to the inputs of elements I.14, allowing the code from the register 15 to go through the inputs of the code-analogue converter 13, as a result At the input of the comparator 7, a signal is produced (Fig. 2) - i n At the same time, the signal of the logical unit from the switch output goes to control 1 and to the input of control node 4-pahr ;; days 1 1 motor phase current and to one of the element inputs And 10. Logical signal ed The connections from the output of the AND 1C element include a controllable switch 2, which connects the high voltage source of voltage 1 to the phase 3 of the stepper motor. The motor phase current I (t) increases according to the law,, {„, (i-e-). | where and is the source voltage, R R 1.1 is the total active center. Anti-erosion of the motor and shunt phase L is the inductance of the motor phase. When the current phase reaches the value.,. , and 4i is the maximum value of the current forcing, at the output of the comparator 7 a zero signal appears, and at its direct input the voltage becomes equal to m -. At the same time, the zero signal C in the course of the comparator 7 is fed to the AC equalizing the input of the delay element 9 and to one of the inputs of the AND 1 element. At the output of the AND 10 element, a logical zero signal appears that locks the key element 2. through shunt 5, the cooling point of the circuit, the control unit 4, the discharge current of the motor phase. When the signal of the logical unit at the output of the distributor, the resistance of the node 4 is negligible,. The discharge current of the phase of the motor 3 is determined by the formula ,, IHVO- ® Since the resistance R Mc1lo / then the discharge process proceeds at a slower rate than the process of current buildup in phase (Fig. 2). It will continue until the current reaches the value. . ; fg ish At the direct input from the comparator 7, the voltage increases to the value of and (FIG. 2). The logical unit signal from the output of the comparator 7 will open element 10 and key element 2, thereby re-connecting phase 3 to power supply 1. This process of maintaining the phase current within tqfi is provided for a time t (Fig. 2), This code arrives from register 17 to the input of delay element 9. When a logical unit signal arrives from the output of delay element 9 to input S of flip-flop 16, the latter generates a logical zero signal at the output, which locks AND 14 elements, thereby turning off The encoder is a code analog 13 from the adder 8. At the direct input of the comparator 7, the voltage is determined by the formula ,, Oy | . ; Jm fr. The current in phase 3 decreases to a value., A. Mind. when reached, a single signal from the output of the comparator 7 ensures that phase 3 is again connected to the power source 1. However, this will maintain the parking current for as long as the signal of the logical unit is at the output of the distributor. At the moment when the output of the distributor of the logic zero at the output of the element And 10 rises, the signal of the logical zero turns off by means of the controlled switch 2, the IoT source of phase 3 until the next moment of the 1st stage mutation, , corresponding to the large resistance of the phase discharge circuit, which provides a rapid fall of the current when it is disconnected. Thus, the proposed device provides a program change of the forcing current and time Forcing impulse on signal signals from a computer or any other software device on registers 15, 17, Equalization also regulates the current of a station by signals from signals entered in register 12. Such an implementation of the device allows to improve the energy characteristics of a step-by-step device. .

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Claims (1)

DEVICE FOR CONTROLLING A STEEP MOTOR, containing a pulse distributor and a multi-channel power amplifier, each channel of which includes a key / 1 element with a motor phase current control unit and a code-to-analog converter with an input current level register, distinguishing it I mean that, in order to improve energy performance, an RS-trigger, a delay element with a delay code register, and AND elements connected with their first inputs to the outputs of the level register are introduced into the motor phase current control unit eye, outputs - to the inputs of the code-to-analog converter and the second input - to the output of flip-flop coupled to the input R - yield of the distributor, and input - with the output of the delay element, its control input connected to the output phase current of the motor control unit.