SU415645A1 - - Google Patents

Description

one

The invention relates to automatic speed controllers for electric drives, namely, analog-to-digital speed ratio controllers, which automatically stabilize a given CKOpocieft ratio of two electric motors connected to each other by a single process.

The proposed analog-digital regulator of the ratio of rotational speeds of electric drives can be used in systems of automatic tension control of paper web, in electric drive systems of sheet-rolling and drawing mills, in various winding machines, in electric drive of tape recorders and many other devices where it is necessary to stabilize with high accuracy the ratio of the speeds of rotation of the two electric motors.

The analog-to-digital speed ratios for electric drives are known, containing two analog-frequency converters and two similar drives consisting of a series-connected digital integrator, a power amplifier, an electric motor, an actuator connected to a roll diameter sensor Ti of a private feedback sensor, the output of which is connected to the input of the digital integrator and tachometric feedback.

The proposed controller is different in that in each drive, the output of the coil diameter sensor and the analog frequency converter are connected in series, and their outputs are connected respectively to the input of the power amplifier and the input.} Of the digital integrator of another drive.

This allows to increase the accuracy of the controller.

The drawing shows the block diagram of the controller.

The structure of the proposed device includes two systems I and II control of electric winders, including frequency sensors 1 and 2 feedback, the frequency of the pulses at the output of which is directly proportional to their speed of rotation, two analog tachogenerators 3 and 4, working mechanisms 5 and 6 (drums of a winder with a tape), sensors of diameters 7 and 8, the output signal of which in analog form is directly proportional to the diameters of rolls of tape on the drums of a winder, electric motors 9 and 10 drives of a winder, linear converters analog frequency 1 and 12, allowed converting the DC voltage from the output of the diameter sensors to the pulse frequency, power amplifiers 13 and 14, providing power to the electric motors 9 and 10, and digital integrators 5 and 16, which allow to integrate the difference of two frequencies: reference frequency fa from the converters analog frequency and feedback / frequency frequencies from frequency sensors. The principle of operation of the analog-digital controller for the ratio of the rotational speeds of the actuators is as follows.

At the moment of switching on, both sides begin to work - analog and discrete.

The analog system works as follows.

The sensors of diameters 7 and 8 produce analog signals proportional to the diameters of the rolls of tapes on the drums. These sensors can be made on any principle (contact or contactless). The analog signals from the outputs of the diameter sensors are fed to the comparison elements and are the driving signals of the analog part of the system.

Signals, proportional to the speed and its derivatives, from analog tachogenerators 3 and 4 are sent to the same reference elements to form a chain of main stabilizing feedbacks, respectively.

To provide highly accurate linear speed stabilization, two discrete equalizers have been introduced into the drive control system, which are digital integrators.

The system of correction of speeds of rotation works as follows.

Analog signals from sensors of diameters 7 and 8 are converted into analogue-frequency (11 and 12) linear-to-pulse (unitary) code with two linear converters.

which is the master for discrete digital integrators (/ s, and / s,).

The frequency signals Ioc.ci and the outputs of frequency sensors 1 and 2 are also fed to the corresponding inputs of digital integrators 15 and 16, which operate on the frequency phase principle and continuously integrate the difference between the two frequencies.

The voltages from the outputs of the digital integrators are fed to the summing inputs of the power amplifiers, making a high-precision correction of the rotational speeds of both electric motors. Due to this, the whole system acquires astatic properties and correspondingly high static accuracy.

Subject invention

An analog-to-digital ratio controller for the rotational speeds of electric drives, for example, winding machines, containing two analog-frequency converters and two drives consisting of a series-connected digital integrator, an electric motor power amplifier, an actuator associated with a coil diameter sensor and a reverse frequency sensor communication, the output of which is connected to the input of the digital integrator and tachometric feedback, characterized in that, in order to improve the accuracy of work in it, in each ivode roll diameter sensor and analog-frequency converter connected in series, and their outputs are respectively connected to the input of the power amplifier and the input of the digital integrator another drive.