SU1700731A1 - Constant current controlled electrical drive unit - Google Patents

Abstract

The invention relates to electrical engineering and can be used in automatic control systems for electric motors. The purpose of the invention is to simplify the drive. The direct current drive comprises an electric motor 1 connected to the converter 2, the first comparison side 3 in series, the rotation speed regulator 4, the second comparison block 5 and the current regulator 6 in series. Series-connected rotational speed sensor 7 and filter 8, the output of which is connected to the input of the first comparison unit 3. Serially connected current sensor 9 and amplifier 10, the output of which is connected to the input of the second comparison unit 5. The output of the corrective model 11 is connected to the input of the first unit 3 of the comparison. The input of the corrective model is connected to the output of the second comparison unit 5. In this electric drive, the feedback signal at the input of the rotational frequency controller 4 is corrected for the dynamic error of the current loop. 2 Il.

Description

The invention relates to the field of electrical engineering, namely to automatic control systems of direct current electric drives, in which rotational speed is controlled using a tachogenerator, and can be used most effectively in closed systems of automated electric drive with high demands on rotational frequency.

The purpose of the invention is to simplify the drive.

FIG. 1 shows the functional cxe-J ma drive; in fig. 2 - a schematic diagram of the corrective model.

The controlled DC motor contains an electric motor 1, connected to the converter 2, connected in series with the first unit 3

comparison, speed regulator 4, second comparison block 5 and current regulator 6, the output of which is connected to the converter 2 input, are connected in series to the rotation speed sensor 7 (tachogenerator) and filter 8, the output of which is connected to the input of the comparison block 3, sensor 9 the current, the output of which through the amplifier 10 is connected to the input of the comparison unit 5, and the correction model 11. The input is connected to the output of the comparison unit 5, and the output is connected to the input of the comparison unit 3, while the correction model is implemented implementing the transfer function LMR) () P +1 + Tw / Tr

Кт С Тм Р (Tfi / + fy) + P + 1 where Р is the Laplace operator;

H

s

Tm - electromechanical constant time;

Tm is the time constant of the current regulator;

Ta) is the filter time constant;

T / L - the non-compensable time constant is small;

Ra is the total active resistance of the core circuit;

Кт - contour gain coefficient;

Ko) is the coefficient of amplification of the loop of the rotational rotation;

C - constructive motor constant.

Structurally, the corrective model 11 can be performed, for example, as shown in FIG. 2. The parameters of the corrective model are as follows:

v

toRsCT + TQ Ri-r-Rz KtSTmTtRaC2

 + Tm Ri R2 Ci - ...., TTTS% e TR: Te + 1 mRltCl The electric drive works as follows.

The input signal is fed to the non-inverting input of the first comparison unit 3, from the output of which, through the series-connected speed controller 4, the second comparison unit 5, the current regulator 6 is fed to the power converter 2. The frequency of rotation of the electric motor 1 is controlled by varying the voltage of the power converter 2 by means of negative feedbacks on current and frequency, rotation taken from current sensor 9 and tachogenerator 7 and fed through current amplifier 10 and filter 8 to the control inputs Oops 6 and 4 current. and rotational frequencies. The input signal of the current regulator 6 through the correction model 11 is fed to the input of the rotational frequency controller 4, while the total feedback signal at the output of the rotational frequency controller 4 is equivalent to the signal reduced by the corrected dynamic error of the current loop.

The proposed design of a controlled DC electric drive

Claims (1)

in comparison with the known ones, it allows to simplify the electric drive, thereby increasing its reliability practically while maintaining dynamic indicators. Invention Formula A controlled DC motor containing a motor connected to a converter, a first comparison unit connected in series, a rotational speed controller, a second one a comparator unit and a current regulator, the output of which is connected to the converter input, serially connected frequency and rotational sensors and a filter whose output is connected to the input of the first comparator unit, a current sensor whose output is connected to the input of the second comparator unit, corrective model, output which is connected to the input of the first comparison unit, and the input of the correction model is connected to the output of the second comparison block, characterized in that, in order to simplify the electric drive, the correction model is made implementing chnuyu function WKM (P 4 KQJ-R, (TcQJ-T / QP + 1 -Tto / Tt Ct С Т „Р (Т + Т /«) + Р Ч-1 where Р is the Laplace operator; Тm is the electromechanical time constant; Tm is the time constant of the current regulator;  constant filter time; Ju - non-compensating constant nna time; P is the total active resistance of the core circuit; Кт - contour gain coefficient; To) - coefficient of contour gain rotational speeds; C - constructive motor constant. / " BUT , 1 t s and. Sax Figg