SU1254575A1 - Device for stabilizing rotational speed of electric motor - Google Patents

Abstract

The invention relates to electrical engineering and can be used to stabilize the frequency of rotation of an electric motor. Improving the stability of the rotational frequency is provided by introducing the pulse generator 11, the integrator 12, the delay circuit 13, the phase detector 14, the adder 15 and the frequency divider 16, and the output of the controlled frequency divider 10 is connected to the second input of the trigger 7, the output of which is connected. with the inputs of the controlled divider 10 and the pulse generator 11, the second input of which is connected to the second input of the adder 15 and the output of the trigger 8, the first input of which is connected to the output of the amplifier 6, resulting in the formation of the current signal frequency with the correction of the sensor manufacturing error for phase auto-tuning Frequency greatly improves the stability of the frequency of rotation of the motor. § (LL: fae. 7

Description

one

The invention relates to electrical engineering and can be used in an automated electric drive to stabilize the rotational speed of an electric motor.

The purpose of the invention is to increase the frequency of rotation of the electric motor.

1 shows a diagram of the device; Fig. 2 shows the driver circuit of Fig. 3 — controlled delay circuit; 4 are voltage diagrams.

The device for stabilizing the frequency of rotation of the electric motor (Fig. 1) contains a sensor unit 1, including a raster disk 2 with marks and two point sensors 3 and 4, two shaping amplifiers 5 and 6 pulses, inputs connected to the outputs of point sensors 3 and 4, triggers 7 and 8, the output of the amplifier maker 5 is connected to the first input of the trigger 7, a reference generator 9 connected to a controlled frequency divider 10, the output of which is connected to the second input of the trigger 8, connected in series to the driver 11 pulses, integrator 12 up exhibited by the delay circuit 13, phase detector 14, adder 15 and divider 16 Toty hour. The output of the controlled frequency divider 10 is connected to the second input of the trigger 7, the output of which is connected to the inputs of the controlled frequency divider 10 and the driver 11 of the pulses, the second input of which is connected to the second input of the adder 15 and the output of the trigger 8, the first input of which is connected to the output of the amplifier -former 6. The output of the reference oscillator 9 is connected via frequency divider 16 to the second input of the phase detector 14. Amplifier - driver 5 is connected to the second input of the controlled delay circuit 13.

The pulse shaper 11., (FIG. 2) contains the element EXCLUSIVE OR 17, the element AND-NOT 18, the element AND 19, the key 20. The inputs of the element EXCLUSIVE AND OR 17 are connected to the first inputs of the element AND-NOT 18 and the element And 19 and are the inputs of the pulse driver 1 1. The output of the element AND THE EXTREME IZH 17 is connected with the second inputs of the element AND-NOT 18 and the element And 19, the outputs of which are connected to the inputs of the CLR 20, the output of which

25

five

tO

fS 20 30 35 40 45

is the output of the pulse former 11.

The controllable delay circuit 13 comprises a series-connected saw-tooth voltage generator 21, a differential amplifier 22, and a pulse shaper 23. The input of the sawtooth generator 21 and the second input of the differential amplifier 22 are the inputs of a controllable delay circuit 13, the output of which is the output of the pulse former 23.

The proposed device for stabilizing the frequency of rotation of an electric motor is. The body works as follows.

The signal from the point sensor 3, amplified and formed in a short positive pulse (a, Fig. 4) is fed to the input of the trigger 7 and sets it to the zero state (b, Fig. 4). From the output of the trigger 7, the resolving potential is fed to the input of the controlled frequency divider 10, which starts counting the reference interval o (in, Fig. 4). At the moment of filling the counters of the controllable divider 10, an overflow signal appears at its output, which sets the triggers 7 and 8; in a single state. In this case, the signal from the output of the trigger 7 prohibits the operation of the counters of the controlled frequency divider 10. After a time interval equal to

T

. nn

where n is the frequency of rotation of the raster

disk, r / s}

N is the number of raster dis- marks. ka 2,

the same label of the raster disk 2 will reach the point sensor 4. Since the distance between the point sensors 3 and 4 is equal to the average distance between the marks, then the output of the trigger 8 will form a sequence of positive pulses, the duration of which is proportional to the time the label passes between two sensors or the frequency of rotation of the raster disk 2 and does not depend on the error of labeling (g, Fig. 4). At the output of the trigger 7, a sequence of positive pulses is formed, the duration of which is proportional to the transit time

3

two adjacent marks past the point sensor 3 or the rotational speed of the raster disc 2, taking into account the geometrical error of the location of the marks (in, Fig. 4). Then, these two sequences of pulses from the outputs of the trigger 7 and 8 are sent to the shaper 11, at the output of the forg, a pulse signal runs with a duration proportional to the difference between the durations of the input signals and polarity determined by the longer duration of the signal from the triggers 7 and 8. If the pulse duration at the output of the trigger 7 is longer than that at the output of the trigger B, then a negative output pulse is formed, otherwise it is positive. This signal is fed to the input of the integrator 12, the output of which produces a constant voltage proportional to the geometric error of the position of the marks of the raster disk 2 of the sensor unit 1. This voltage is applied to the control delay circuit 13, in which the pulse sequence, fed through the amplifier-shaper 5 from the point sensor 3 and representing the current frequency from the sensor, is corrected in accordance with the linear error signal. The output signal from the controlled delay circuit is fed to the phase detector 14, to the second input of which through the frequency divider 16 a reference signal is supplied from the reference oscillator 9. The output signal of the phase detector 14 and the output of the trigger 8 is fed to the slider 15. Output signal of the adder 15 proportional to the sum of the signals from phase detector 14 and trigger 8.

The formation of the current signal frequency with the correction of the sensor manufacturing error for the phase-locked loop frequency significantly increases the frequency stability of the motor.

Claims (3)

1. An apparatus for stabilizing the frequency of rotation of an electric motor, comprising a sensor unit, including a raster disk with marks and two point sensors, two pulse shaping amplifiers, inputs connected to point outputs 545754 sensors, the first and second triggers, the output of the first amplifier pulse generator is connected to the first input of the first trigger, the reference 5 generator connected to a controlled frequency divider, the output of which is connected to the second input of the second trigger, differs from 10 stability of rotational frequency, sequentially connected pulse shaper, integrator, controlled delay circuit ki, phase detector, adder, and T5 also a frequency divider, while the output of the controlled frequency divider is connected to the second input of the first trigger, the output of which is connected to the inputs of the controlled frequency divider 20 and the pulse former, the second input of which is connected to the second input of the adder and the output of the second trigger, the first input of which is connected to the output of the second amplifier, the output of the reference generator is connected to the second input of the phase detector through a frequency divider, and the output of the first amplifier form with It is connected with the second input of the controlled delay circuit. 2. A device according to claim 1, characterized in that the pulse shaper contains an EXCLUSIVE OR element, an AND-NO element, an AND element, a key, and the element inputs are EXCLUSIVE OR connected to the first inputs of the AND-NOT element and the AND element are The form of the 40 pulse pulse, the output of the EXCLUSIVE or OR element is connected to the second inputs of the NAND element and the AND element, the outputs of which are connected to the key inputs, the output of which is the output of the pulse shaper. , 3. A device according to claim 1, characterized in that the control delay circuit comprises a saw-voltage generator connected in series, a differential amplifier and a pulse shaper, while the input of the saw-voltage generator and the second input of the differential amplifier 5 are inputs of a controlled delay circuit, the output of which is the output of a pulse shaper. 35 fug. Z fig 3 0iu. f