SU1130981A1 - Phase shifting device - Google Patents

Abstract

A PHASE DEVICE device containing a network-connected functional converter, the output of which is connected to the input of a voltage-frequency converter, the output of the converter is connected to the counting input of a summing counter, the output of which is connected to the first input of the comparator unit, the second input of the comparator unit is intended for connecting a switch. To the source of the reference signal, characterized in that, in order to increase the linearity of the adjustment characteristic when the nature of the load changes, it is equipped with a subtracting counter, a counting trigger, a switch and a delay element, and the functional converter is implemented as a rectifier, and the output of the voltage converter is the frequency is connected to the first input of the switch and the input of the counting trigger, the output of which is connected to the second input of the switch and the counting input of the summing counter, the zero setting input The second one is connected to the output of the delay element, and the bit outputs are connected to the lower bit inputs of the detracting counter, the upper bit input of which is connected to the common bus, the recording input is connected to the input of the delay element and is intended to be connected to the synchronization source, the output outputs are connected with the second input of the comparison unit, the counting input with the output of the switch, the control input of which is intended to be connected to the source of the preconverter operating mode signal. iUD 00

Description

The invention relates to electrical engineering, in particular, to converter technology, and can be used in the construction of digital control systems for single-phase thyristor converters.

A phase shifter is known, which contains a trigger, an AND element, a reference frequency generator, a cosine function generator, consisting of a time distributor, an OR element and a subtracting counter, a comparison unit, and a delay element. The device provides a linear relationship between the control signal and the output voltage of a thyristor converter with inductive load tl.

The drawbacks of the device are its complexity, caused by the complexity of the circuit and the large hardware volume of the cosine function generator, and the change in the transmission coefficient of the control device — the thyristor converter during voltage fluctuations in the network.

The closest in technical essence to the present invention is a phase-shifting device containing a network-connected functional converter, the output of which is connected to the input of a voltage-frequency converter, the output of the converter is connected to the counting input of a summing Counter, the output of which is connected to the first input of the comparison unit The second input of the comparator unit is designed to be connected to the reference signal source. The use of this device as part of a pulse-phase control system of a thyristor converter ensures a stable linear relationship between the output voltage of the converter and the control signal under inductive load of the converter.

A disadvantage of the known device is that when the thyristor converter is active, its control characteristic (the dependence of the output voltage on the control signal) is different from linear.

The aim of the invention is to increase the linearity of the adjustment characteristic with changing nature of the load.

1309812

The goal is achieved by the fact that a phase-shifting device containing a network-connected functional converter, whose output is connected to the voltage-frequency converter input, the output of the converter is connected to the counting input of a summing counter, the output of which is connected to the first input of the unit, compared to the second input. the comparator unit is designed to be connected to the reference signal source, equipped with a subtracting counter, a counting trigger, a switch and a charge element, and the functional converter is made in de rectifier -, wherein the converter output voltage-frequency coupled to the first input of the switch and the input of countable

0 trigger, the output of which is connected to the second input of the switch and the counting input of the summing counter, the input of the zero setting of which is connected to the output of the delay element, and

5 bit outputs are connected to the lower bit inputs of the subtracting counter, the leading bit input of which is connected to the common bus, the record input is connected to the input of the delay element and is intended to be connected to the synchronization signal source, the bit outputs are connected to the second input of the comparator, the counting input is with the switch output, the control input of which is intended to be connected to the signal source of the converter operation mode.

FIG. 1 shows a functional diagram of the proposed arrangement in FIG. 2 - timing diagrams for the operation of the device.

R

Phase shifter consists

- from rectifier 1, converter

voltage-frequency 2, counting trigger 3, switch 4, summing counter 5, subtractive counter 6, comparator unit 7, and delay element 8. The input of the rectifier 1 is connected to the network, the output of the rectifier 1 is connected to the input of the voltage-frequency converter 2, the output of which is connected to the input of the counting trigger 3 and the first input of the switch 4. The output of the counting trigger 3 is connected to the counting input of the summing counter 5 and c the second input of the switch

3

. The bit outputs of the summing counter 5 are connected to the inputs of the lower bits of the detracting counter 6, the high-level input of which is connected to the common bus of the device, and the counting input to the output of the commutator 4, the multi-bit output of the detracting counter 6 is connected to the second input of the compare unit 7, the first input of which is connected to the source of the reference signal Nj, the input of the record of the reading counter 6 and the delay element 8 are connected to the source of the synchronization signal C, and the output of the delay element 8 is connected to the input of the zero setting summing 5 Meters withstand.

The device works in the following manner.

A sinusoidal network voltage is applied to the input of miter 1

U, (t) V 5inwt -,

where V is the amplitude value of the voltage,

W - angular frequency. The voltage Ijg (i) at the output of rectifier 1 varies according to the law

Ue (t), -n "/ t /.

The signal Ug (t) from the output of the rectifier 1 is fed to the input of the voltage-elucidum converter 2. The frequency of the signal f (t) at the output of the latter is proportional to the voltage Ug (t)

f (i) kUg (iJ-kV / 5 "nvx / -t7,

where k is the voltage-frequency converter gain.

The signal f (I) through the counting trigger 3 is fed to the counting input of the summing counter 5, the input of the zero setting of which through the delay element 8 receives a synchronization pulse. Moments The occurrences of pulses c correspond to the moments of zero crossing of the voltage U. (i) (Fig. 2). In each half-period of the voltage Uj. (T), starting from the moment of the appearance of a pulse c, the counter code 5 changes according to the law

t

R kV (-c,)

about where {(About I f -, () - | v (sihwi) 1309814

frequency of the output signal of the counting trigger 3 ..

At the end of the half cycle, at the time of arrival of the next synchronization pulse with t i vr4n, each

the impulse c, affecting the input of the record of the subtractive counter 6, writes the final value Nc to it

mr

the most significant bit of counter 6 is written to 0. With a delay, summing counter 5 is reset to the zero state. The process then repeats. As a result, at the beginning of each half period in subtractive I ..

counter 6 recorded number

The change in time of the NiCj code of counter 6 depends on the operation mode of the thyristor converter.

When operating at an inductive load, the value of the signal of the converter operation mode, arriving at the control input of switch 4 and

depending on the mode, it is set equal to 1. Switch 4 passes to the counting input of the subtracting counter 6 a signal from the output of the voltage-frequency converter 2. The code HC (-i) of the subtractive counter 6 changes according to the law

t k f VV

() (t) - co5Wi.

The signal NC2 (i) is fed to the input of the comparator unit 7. In block 7, the value of NC2 (t) is compared with a predetermined value. Q control pulse is generated at the moment of equality

t

“-,

NC (I coswt

(one)

W

The angular position of the pulse Gl relative to the beginning of the half period is determined by the solution of equation (1)

"N,

 Wt oirccos-

 (g)

,

 m

In the considered continuous current mode, the regulation characteristic of the thyristor converter

has the appearance

  , cos,

Claims (1)

A PHASE-MOVING DEVICE containing a functional converter connected to the network, the output of which is connected to the input of the voltage-frequency converter, the output of the converter is connected to the counting input of the totalizing counter, the output of which is connected to the first input of the comparison unit, the second input of the comparison unit is designed for value to the source of the reference signal, characterized in that, in order to increase the linearity of the adjustment characteristic when the nature of the load changes, it is equipped with a subtracting counter, counting trigger, switch and delay element, and the functional converter is made in the form of a rectifier, and the voltage-frequency converter output is connected with the first input of the switch and the input of the counting trigger, the output of which is connected to the second input of the switch and the counting input of the totalizing counter, the zero setting input of which is connected to the output of the delay element, and the bit outputs are connected to the lower bit inputs of the subtracting counter, the highest bit input of which is connected to the common bus, the recording input is connected to the input of the delay element and is intended to connect to the source of the synchronization signal, the bit outputs are connected to the second input of the block comparison, the counting input - with the output of the switch, the control input of which is designed to connect to the signal source of the operating mode of the Converter. SU „„ 1130981 a