SU1246329A1 - Device for controlling polyphase stepping electric motor - Google Patents

Abstract

The invention provides for a decrease in speed oscillations when a stepper motor is in operation. The motor control unit is connected to the motor phases 1 and comprises a threshold element 2, a pulse shaper 3, a power amplifier 4 that performs phase switching, a trigger 5, a current sensor 6, a diode 7 bypassing the motor phase, the node 8 for setting the power amplifiers to initial state, including a resistor 9, a capacitor 10 and an inverter 11, a switch 12, a resistor 13. A series connection of the phase to the current sensor and the signal from the sensor to the control channel of the subsequent phase allowed using the threshold element to receive avtosin.hronny mode with small wobbles speed. 2 Il. (L N: i4 O) WITH | WITH WITH

Description

This invention relates to the control of electrical machines for can be used in robotics.

The purpose of the invention is to reduce speed fluctuations when the engine is running.

FIG. 1 shows a functional diagram of the device in relation to a three-phase stepping motor; in fig. 2 - time diagrams of currents in the phase windings of an electric motor.

The motor control device is connected to motor phase 1 and contains a threshold element 2, a shaper 3 pulses, a power amplifier 4, which is presently commanded phase switching, a trigger 5, a current sensor 6, a phase-shunting motor diode 7, the node 4 of the power amplifiers 4 to the original a state including a resistor 9, a capacitor 10 and an inverter 11, a switch 12, a resistor 13.

The motor control device operates as follows.

GFI p1, power supply Un, and the first moment of time and at the input of inverter 1 by charging capacitor 10 through a resistor 9, maintains a voltage level corresponding to a logical "O, which determines the level of the output voltage of the inverter corresponding to a logical" 1. After the voltage on the capacitor 10 reaches the level of "1", the inverter 11 is switched, which corresponds to a pulse decay at the output of the inverter. This pulse decay records information contained at the inputs D of the flip-flops 5. Since the input D of the flip-flop 5 of the first channel is connected to the UMI power source via a resistor 13, which corresponds to the logical "1, and the trigger inputs of the other channels are connected to the common wire, which corresponds to the logical "Oh, then the output of the trigger 5 of the first channel is supplied unlocking signal to the power amplifier - transistor 4, and in the remaining channels transistors 4 are closed, thus the phase winding 1 of only the first channel is turned on.

When the switch 12 is installed, for example, in a circuit connecting the current sensor 6 of the first channel to the input of the second channel element 2, the voltage from the first channel current sensor 6 enters the input of the second channel threshold element 2, which switches, if more UonSignal from the threshold element 2 is fed to the shaper of 3 pulses, where a short pulse is generated that arrives at the S-input of the second channel trigger

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and to the R input of the first channel trigger. With this. the phase winding of the second channel is switched on and the phase winding of the first channel is turned off.

The current of the phase winding 1 of the second channel, the increase exponentially, causes a similar increase in the voltage on the sensor 6 of the current of the second channel associated with the input of the threshold element 2 of the third channel. Thus, when the input voltage reaches the threshold element 2 magnitude, exceeds the magnitude of the reference voltage and one, the threshold element 2 of the third one switches, i.e. the phase winding 1 of the third channel automatically turns on and the phase winding 1 of the second channel is turned off. Then, the phase winding of the first channel is turned on and the phase winding of the third channel is turned off. Then the cycle repeats.

To stop the engine, it is enough to open the key 12, which leads to the inclusion of the phase winding of the first channel and the disconnection of the phase windings of the other channels.

In comparison with the known devices used by electric motors, using a series connection of a phase winding with a current sensor and applying a signal from the current sensor to the control channel of the next phase allowed using the threshold element to obtain an auto-synchronous mode with small speed fluctuations and, moreover, to create torque drive with torque moment. By changing the reference voltage, it is possible to vary the torque and speed developed by the motor.

Claims (1)

Invention Formula A multi-phase stepper motor control device comprising control channels for the number of motor phases, each of which includes a power amplifier, a current sensor and a series-connected threshold element and a pulse shaper, characterized in that, in order to reduce speed fluctuations during engine operation, An RS-trigger is connected to each channel, the output is connected to the input of the power amplifier, the S-input is connected to the output of the pulse former and the R- input of the trip- er of one channel adjacent to it, the current sensor is connected to edovatelno yield power amplifier and to the input of the threshold element of another channel adjacent to it, wherein one of the channels introduced switch connecting the current sensor to its input threshold element adjacent to channel them. one rL C3 I n V. FIG. 2