SU752727A1 - Apparatus for reversible step electric motor control - Google Patents

Description

one

The invention relates to an electric drive and can be used in automatic control systems with stepper motors, in particular, to stabilize their speed.

A device for controlling a stepper motor is known, which ensures its operation in the mode of a contactless DC motor and speed stabilization by signals from the pulse sensor 1.

However, in such a device, the switching of the windings of the stepper motor takes place when the shaft is rotated by a certain step, which leads to noticeable oscillations of the electromagnetic torque and causes a significant detonation of speed. In addition, due to the relay mode of maintaining a given speed, there are increased requirements to the accuracy of the pulse position sensor 20 and the speed measurement element, and it also becomes necessary to force the transient electromagnetic processes of the engine to achieve low speed detonations.

The closest in technical essence to the invention is a device for controlling a reversible stepper motor with a pulse sensor mounted on a shaft through a transmission mechanism.

com position, equipped with a directional separation unit, connected to the engine control unit and the regulators are tense on the motor phases connected to the speed controller through a nonlinear converter code-analogue and reversible pulse distributor with a synchronizer and prohibition elements

2

However, in this device there are also significant fluctuations in speed when it is maintained, due to the operation of the stabilization system in the relay mode.

The aim of the invention is to reduce the detonation rate when it stabilizes.

The goal is achieved by introducing a command signal generation unit, a frequency subtractor, two two-input OR elements and two two-input AND elements, one inputs of which are connected to the output of the speed setter, the second input of the first element I - with one output of the command generating unit, the second the input of the second element is with the other output of the same node, the first input of one element OR is associated with the output of the first element AND, and the second input with one output of the selection circuit of motion nanowire, the first input of another IL element

connected to the output of the second element AND, and the second input to another output of the dv / keni directional separation circuit, in addition, the outputs of the OR elements are connected to the inputs of the frequency subtractor whose outputs are connected to the synchronizer inputs.

Such a device can provide for the static stabilization of the speed of a stepper motor with digital integration, carried out by the main elements of the device.

The drawing shows a block diagram of the device in relation to a four-phase stepper motor.

The device contains a node .formed command signals 1, a synchronizer 2, prohibition elements 3 and 4, a reversible pulse distributor 5, the outputs of which are connected to a control unit and a stepping motor 6 connected by its shaft via a transmission mechanism 7 with a pulse field sensor 8, the directional separation unit 9 connected to the outputs of the synchronizer 2 with its outputs. The outputs of the distributor 5 are also connected to the inputs of the voltage regulators 10 and 11 through converters, the code is analog 12 and 13. At the inputs of a snc and 2 also connects the outputs of frequency subtractor 14, the inputs of which are connected to the outputs of the OR 15 N 16 elements. One output of the OR element 15 is connected to the output of an AND 17 element, and the second to the output of the AND allocation direction block 9. To one input of the element OR 16 is connected to the output of the element AND 18, and to the second - output B of block 9. Some inputs of elements 17 and 18 are connected to the output of the master frequency generator 19, and others to the outputs B and H of the command signal generation node 1.

The device works as follows.

In the initial state, the signal of the command generation unit 1, prohibit elements 3 n 4, do not transmit pulses from the allocation unit of the driving direction 9 to the inputs of the reversing pulse distributor 5. At the same time, the pulse distributor sets some combination of the stepped motor phases on, and converters code analogue 12 and 13 are produced at the inputs of voltage regulators 10 and AND setpoints, the value of which is determined by the state of the distributor 5. The voltage regulators are set on the switched-on phases of the movement Atel permanent voltage (current) and the rotor is fixed in ioloLSeiii, oiredel emom kombiiatsney included phases and magnitudes voltages (currents) in these phases. The isolated state of the circuit will not change with the prohibition signal from elements 3 and 4 and the absence of signals B and H at the outputs of node 1, because the rotor of the stepping motor is not raised and the pulses from the sensor do not come. The outputs of the dedicated 9 unit are connected to the input of the reversible distributor 5 in such a way that, if the rotor of the engine is displaced by external forces in the same direction, the impulses from the sensor cause the same spatial non-displaced vector of the stator motor, and the source changed, the component changed, and the component changed the same pattern. 5. At the same time, the electromagnetic moment developed by the generator will be zero.

In the case of potential

the signal at output B of node 1 is resolved and the emits of the set frequency / 3 from generator 19 through element 17 and through element 15 to one of the inputs of frequency subtractor 14. Since the rotor of the motor is first non-movable, then the output of subtractor of frequencies connected with the input In synchronizer 2, io in mc pulses with a frequency of / 3- At least one pulse will pass to the input B of the distributor. With

In this case, the magnetic stator vector will shift to the position causing the rotor to move forward. The pulses from the position sensor 8, passed through block 9, are fed to the vehicle at its output B, and are received through the silicon 2 to the input B of the distributor 5, oscillating the displacement of the stator zero vector and the corresponding rotor of the engine. Due to the fact that the frequency difference / z- / oc (where / oc is the frequency

rotation of the rotor) with increasing engine speed decreases and, when reaching a given value, staiows equal to zero, only the limited number of pulses from the output of the subtractor 14 will pass to the input B of the distributor 5 during the runtime. The moment developed by the frequency divider is proportional to this number of pulses. It will exceed the torque on the engine shaft; the speed will exceed the set and pa output

frequency detractor, coupled with the input of the H of their sinchroinzator 2, in ts pulses with a frequency of / 00- / 3 and the torque of the engine decreases, since the magnitude of the mismatch between the stator zero and the rotor of the engine

also know how. Engine speed will decrease. After the end of the starting process, the rotor of the engine will move with a speed determined by the reference frequency.

Claims (2)

1. Author's certificate of the USSR 502470, cl. And 02P 7/60, 1974. 2. USSR author's certificate number 556542, cl. And 02 K 29/02, 1974.