SU760362A1 - Dc electric drive - Google Patents

Description

The invention relates to electrical engineering and can be used in high-speed systems with pulse-width converters of direct current.

A device for controlling a pulse-width converter with direct current, containing a controlled proportional-integral controller, a current sensor in the load circuit, the output of which is connected to the input of the reference unit Eadan, the load current value with its actual value, and the output of the comparison node is known. with an input proportional-integral controller [1} The use of a known device in automatic control systems does not allow for high performance in the whole range due to the dependence of the loop gain on the magnitude of the ripple factor, determined by the duty cycle of the output pulses of the DC pulse converter. This is especially true in cases where it is necessary to obtain extremely high speed, in particular, when

DIRECT CURRENT

2

obtaining transient 'processes of finite duration.

The closest to the invention to the technical essence is a DC electric drive containing a motor connected to the output of a pulse-width converter connected via a feedback sensor to one input of the reference node, to the output of which is connected to the output of the reference node, to the output of the comparison node proportional-integral regulator with an input resistor, a shunted semiconductor key, the input of which is connected to the output of the auxiliary pulse-width converter, and the output d PI regulator is connected to the input of a pulse converter shirotno20 [2).

In a known electric actuator, the parameters of the proportional and global gr of the regulator are corrected as functions of the controlled output 25 of the electric drive parameters. This allows you to increase the speed of such a regulatory system. The disadvantage is the impossibility of obtaining the maximum speed due to the fact that when using the correction 760362

As a function of the output parameters, such a self-tuning system may turn out to be structurally unstable. In addition, an additional functional converter of the output parameter is required, which controls the auxiliary pulse-width converter.

The aim of the invention is to increase the speed in the whole range of non-regulation and to simplify the device. This goal is achieved by the fact that in a known electric

“~“ WIRELESS INTEGRATELY pulse width transducer connected to the output of the /, sensor. ].

FIG. 1 is a block diagram of an electric drive; in fig. 2 - in the function of the reference signal, the curves of the variation of the contour gain and · of the Yaghoy signal of the auxiliary ·.

"pulse-pulsed transform.

...., DC motor

contains a pulse-width converter 1 with a motor 2 connected to its output, a proportional-integral controller 3 with an input resistor 4, a bypass semiconductor switch 5, while the control input of the key is connected

• ^g With the “output” of the auxiliary ³ neural-pulse converter 6, the input

““ '' 'Which, in turn, is directly connected to the setter 7. The input resistor 4 is proportional-int'egralnogo regulator 3 connected to the output of the comparison node 8, the inputs of which are connected to the setpoint 7 and the feedback sensor 9 of the electric motor 2. In addition to that, proportional-integral controller 3 contains an operational amplifier of direct current 10 with a large coefficient.

’T0“ Gains.

The setting signal 7 compares with

The 'sy' gyal feedback sensor 9 in the comparison node 8, and the error signal is fed 'to the input' of the transient-integrated regulator 3, where * it is corrected as a function of the sig, * ^, n ^ ya ~ 's'aDanhia by means of pulse-width converter b is amplified. The amplified “signal arrives at the input of the main pulse-width converter £, made according to the well-known scheme, which supplies the electric motor 2. In order to obtain the maximum speed of the system in the entire regression range, the ratio

where (T _g 5 + 1) T ₄ 5

1 / (T _p 5 + 1)

five

'R

the transfer function of the proportional-integral controller 3; load transfer function (electric motor 2); the value of the ripple factor

15

't

changing the dynamic gain of a closed-loop auto-regulation system with a pulse-width converter of direct current;

- modulation period of the pulse-width converter.

From condition (1), taking into account the value of P, the law of change of the gain K for the proportional-integral regulator 3 (FIG. 2) is determined, which is a close dependence of this

coefficient of the value of the signal setting device. When skachkoobraenom change setpoint 7 signal for invariability dynamic properties of one ^ p temporarily regulated input impedance 4, a proportional-integral regulator 3 due to changes in the ratio between the duration of ON and OFF h / of states of the semiconductor switch 5 linearly obtainable 'due to a linear change in output voltage 0 _spike (Fig.2) auxiliary pulse-pulse converter 6, with the contour of the gain of the system varies hyperbolicly Mu law in the function of changing the signal setpoint 7.

Techno-economic effect of

45 use of the invention is to ensure the possibility of obtaining the ultimate speed in the entire range of regulation, by creating a structurally stable

50 systems / with the properties of processes of finite duration and in simplification of the Electric Drive due to the exclusion of hardware complex functional converters of the Output „

/ parameters that control the auxiliary “pulse-width pulse converter. '

Claims (1)

Claim t ₂ = "t _with [1-e * p (-T / t _about uP 'Y T, = PT [1 - exp (-7,% 1]), (ΐ) 60 DC electric drive,. containing a motor connected to the output of a first pulse-width converter connected via a feedback sensor to a single input 65 knots sraVyyonya, to another input kopri 'reduced to the pulse-width converter of the transfer 'functions' of the control system _ ~ Y „(5) = (T ₂ 5 + 1) (T <5 (T _about 5 + 1), (2) . ·; <. χ-Chal- * vy th 760362 The output of the setpoint device is connected to the output of the reference unit, a proportional-integral controller with an input resistor, a shunt semiconductor switch connected to the output of the second pulse-width converter, and the output of the proportional-integral controller connected to the input of the first pulse-width converter, which , that, in order to increase the speed of simplification, the input of the second width — im — pulsed transducer — is connected to the output of the setter. _