SU1352600A1 - Single-channel device for controlling thyristor converter - Google Patents

Abstract

This invention relates to electrical engineering and can be used in static converters. The purpose of the invention is to improve the accuracy of control, expansion of functionality. In this device, the charge current of the capacitor 4 does not depend on the voltage at the junction point of the capacitors 3 and 4, which leads to the stability of the angle transfer coefficient in the full control range. 2 hp f-ly, 2 ill. С -JF UK I .gL I ru cpue.i I1

Description

The invention relates to electrical engineering, in particular, to converters with automatic control of the output value (on, current, etc.),

The aim of the invention is to improve the accuracy of regulation, expanding the functionality of the device.

Fig. 1 is a diagram of the control device of the valve converter; Fig. 2 is a diagram of an integrator with a voltage-to-current converting node implemented on a transistor;

The device contains the first source 1 of the reference voltage, the integrator 2, the first 3 and the second 4 capacitors in the feedback circuit of the operational amplifier, the input resistors 5 and 6, the reset switch 7, the voltage-to-current converter 8. A comparator 9 and an output driver 10 pulses are connected in series with the integrator. The output driver 10 is connected to the control electrodes of converter valves 11, the control input of the reset switch is connected to a pulse generator 12, a second source 13 of the reference voltage is connected to the second input of the comparator, control voltage Uj / and voltage are connected to the input resistor 5 and 6 feedback C (5c, from the output of the converter 11,

The device works as follows

In the synchronous mode of operation, the pulse generator 12 produces short pulses rigidly connected to the mains voltage (the generator input is connected to the mains voltage), the synchronization pulses fed to the control input of the switch 7 periodically zero the capacitor 4, the capacitor 4 charge It comes from a current source 8. For the connection point of the capacitors, 3 and 4 during the charging process, the equation

: +

TG

Of kU- - current on

g output node

eight;

 R5 has a control current;

R /

- feedback current;

R,

k is the conversion factor of node 8; RJ - resistances of resistors 5,6,

Under the condition Y, the current Y of the charge of the capacitor 4 is equal and completely determines the law of voltage variation on the capacitor in accordance with the formula

and.

/ dt.

15

and hence the transmission coefficient of the device by the angle “i wt, t, e.

di dUc.

dwt we dUc

0

five

0

0

five

0

five

Where

with w capacitance of 4; circular frequency network. The initial voltage at the output of the integrator 2 at the moments of synchronization is equal to the voltage on the capacitor 3 and is determined in the steady state. shems mode of condition / (i, -i,) dt o,

mean values and reverse current means that neither the control current I

five

Node 1, which is proportional to the output value of the converter, is equal to each other. In this way, the static error value is zero in synchronous mode.

At the same time, the required value of the control angle C is determined by comparing the voltage at the output of the integrator 2 (the sum of the voltages on the capacitors 3 and 4) with the reference voltage Vg at the input of the comparator 9, the higher the voltage on the capacitor 3, the faster the total voltage capacitors 3 and 4 will reach the value of the reference voltage Uo and less will be the angle (. This will lead to an increase in the voltage on the high voltage of the converter in accordance with the control voltage,

In asynchronous mode, the device. control works similarly. The generator 12 in this mode is triggered by pulses from the output driver 10,

The simplest means of implementing a voltage-to-current node is to use a transistor 14 circuit.

U "R

r

and resistor 15 (Fig. 2). The current in the circuit (FIG. 2) is equal to

uj, - and,,

R,

where UZ - the transfer coefficient of the transistor in the circuit with a common emitter}

emitter-base voltage; the resistance of the resistor 15, in Unlike the known devices in the proposed device control the charging current of the capacitor 4 does not depend on the voltage at the junction point of the capacitors 3 and 4, This ultimately leads to the stability of the angle transfer coefficient in the full control range, the extension of the control range , improvement of adjusting properties in dynamics. The enhanced functionality is associated with the ability to work in both synchronous and asynchronous mode.

Claims (2)

Invention Formula 1, Single-channel device for controlling a valve converter containing two sources of reference voltage, an error signal integrator performed on an operational amplifier whose feedback circuit includes Compiled E, Kalinkin Editor N, Slobod nickname Tehred M. Khodanych Order 5573/54 Circulation 659 VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Rauschska nab., d, 4/5 Production and printing company, Uzhgorod, st. Project, 4 tori, the reset key of the second capacitor, the control input of which is connected to the terminals for connection to the AC network, the comparator, the output of which is connected to the input of the output pulse generator, the first input of the comparator is connected to the first reference voltage source, and 0, its second input to the output of the error signal integrator, characterized in that, in order to improve the control accuracy, a voltage-to-current conversion node is introduced, 5 whose input is connected to the second reference voltage source, and the output to the common connection point of capacitors, 2. The device in accordance with clauses 1, 1, 2, and 10 is that the node converting the voltage to current is made on a transistor whose emitter is connected through a resistor to the input terminal of the node converting 5, the base is connected to the common power bus, and the collector is connected to the output terminal of the conversion unit, 3, The apparatus according to claim 1, wherein, for the purpose of 30 extensions of functionality, a pulse generator is introduced into it, the output of which is connected to the control key to the input of the reset key, and the input is connected to the terminals Preference I. Muska Subscription