SU1220087A1 - Device for phase controlling of rectifier converter - Google Patents

Abstract

The invention makes it possible to increase the noise immunity of the device for phase control of a valve converter consisting of a synchronously connected node, a phase displacing unit, a delay unit 7 and a distributor. Specified ..j L-i.:kl -AJ. (P s / f n yffn g 1S

Description

This effect is achieved by the fact that the delay unit 7 is made in the form of a sawtooth voltage generator 8, a constant component separation unit (repeater 9 and a capacitor 10), and a comparator 11 connected in series. The generator 8 is connected to the output of the phase-shifting unit (3-6), the output of the comparator 11 is connected to the input

The invention relates to electrical engineering, primarily to phase control systems for AC-DC converter DC converters.

The purpose of the invention is to improve noise immunity.

Figure 1 shows the proposed device; 2 and 3 are diagrams of the operation of the device nodes.

The phase control system (in Fig. 1) is formed by a synchronization unit consisting of a block 1 of comparators and a selector 2 of clock pulses, a phase-shifting block containing a generator 3 sawtooth voltage, a comparator 4 forming an RC circuit 5 and an output driver 6, a block of delay 7 including the second generator B of the sawtooth voltage, the DC separation unit (repeater 9 and capacitor 10), the comparator 11 forming the KS circuit 12 and the output driver 13 of the delay unit. The distribution of the control pulses over the channels of the valve converter is carried out by a pulse distributor, which is made on the flip-flops 14 and 15 and logic gates ZI 16 connected by outputs to amplifiers 17 pulses. The operation of the distributor is controlled by the block of drivers 18 and driver 19, the input of which is connected to the OR element formed by diodes 20.1 and 20.2. (

The device works as follows.

The inputs of the comparators 1 are connected to a source of synchronizing voltages (respectively, with its phases L,

do distributor (14-17). If the sawtooth voltage generator 8 malfunctions due to a change in the voltage amplitude, the phase of the pulses generated by the delay unit does not change, which makes it possible to increase the noise immunity of the phase control system. 1 h. n. f-ly, 3 ill.

B, C). The comparators of unit 1 operate in such a way that, during the action of the positive half cycles of the synchronizing voltages at the inputs of the comparators, their output signal has a positive polarity, while under the action of the negative half cycles, it is negative. For generating synchronization pulses - comparators outputs

block 1 is connected to shortening differentiating chains. The shape of the pulses at the output of the Comparators unit 1 and their phase position relative to the synchronizing voltage are shown in diagrams 21-24 (Fig. 2). The pulses thus obtained are fed to the selector 2 of sync pulses, which selects pulses that coincide with the onset of negative half-periods. The pulse shape at the output of the selector 2. Shown in figure 2-25. The sawtooth generator 3 produces a sweep voltage (diagram 26,

Fig. 2), which is fed to a non-inverting input of comparator 4.

The inverting input of the comparator 4 is supplied with a reference voltage, the value of which determines the shift of the generated pulses relative to the synchronization pulses. When the current value of the sawtooth voltage reaches the target, the comparator 4 switches and a positive polarity signal is set at its output (Figure 27, Fig. 2). From the leading edges of the indicated signals by the differentiating circuit 5, short pulses are formed (diagram 28, figure 2), which are fed to the input of the former 6 and to the input of the second generator 8 of the sawtooth

3

voltage included in the delay block. The sawtooth generator 8 generates a sawtooth voltage (diagram 29, FIG. 2) synchronized by pulses received at the output of the phase-shifting unit containing generator 3 and the comparator 4 and, therefore, when the voltage of the reference voltage changes, the resulting voltage is shifted in phase relative to the pulses , taken from the output of the selector 2 clock pulses. The emitter follower 9, together with the capacitor 10, forms a unit for separating the DC component from the sawtooth voltage of the generator 8. As a result, the sawtooth voltage does not contain a DC component at the input of the comparator 11 (Chart 30, FIG. 2). the voltage of the positive value of the comparator 11 switches, and the differentiating circuit 12 forms an im- (diagrams 31 and 32, figure 2), which is independent of the magnitude of the reference (i.e., the magnitude of the phase shift of the pulses taken from the output device) halves the time period between the two current pulses of the phase shifting device. In case of disturbances in the operation of the sawtooth generator 8 (diagram 30, fig. 2) of the sawtooth voltage changing in amplitude, the phase generated by the pulse delay device does not change, which makes it possible to increase the noise immunity of the phase control system. The pulses generated in this way are fed to the input of the imaging unit 13 and to the diode 20.1, which together with the diode 20.2 form a logical element OR connected to the input of the imaging unit 19. The imaging unit 6 and 13 form the pulses used to control the operation of the pulse distributor. The output sequence of pulses removed from the imaging unit 13j is shown in diagram 33 (FIG. 2), and from the imaging instrument 6, in diagram 34 (FIG. 2). From the output of the former 19, the pulses shown by diagram 35 are removed (Fig. 2). The control distributor consists of three identical channels, each of which contains a trigger 14 and 15, an element of the inverter circuit - 16, and an output amplifier 17.

200874

Consider the operation of one of the distributor channels (channel A), Triggers 14 and i 5 are inverse controlled triggers. Transfer

5, the trigger 14 in a single state is produced by the output signal of the corresponding driver 18 at the beginning of the negative half cycle of phase A, and the translation of the trigger 15 by the output signal of the driver 18 at the beginning of the positive half period of phase A. The indicated processes are shown for trigger 16 by diagrams 36 and 37 (Fig. 3), and for trigger 14 - diag 5 by frames 36 and 40 (Fig. 3). Setting the flip-flops 14 and 15 to the zero state is made by the output signals of the formers 6 and 13, respectively. Diagrams 39 and 42 at the inverse outputs of the flip-flops 14 and 15 are shown in FIG. The inverse outputs of the flip-flops are connected to the inputs of the ZI element, the third input of which is fed with a sequence of pulses from the output of the force maker (Diagram 43, FIG. 3). As a result, dual pulses are given at the input of amplifier 17 (diagram 44, fig. 3), which are necessary for controlling the bridge valve 30

Initiator.

Claims (2)

Invention Formula 1, a device for phase control of a valve converter a synchronized node, a phase shifting unit, a delay unit and a distributor, characterized in that, in order to improve noise immunity, the delay unit is made in the form of a sawtooth generator, a DC separation unit and a comparator connected in series, the input of the sawtooth generator connected to the output of the phase shifting unit, and the output of the comparator to the distributor input. 2. Pop-1 device, distinguished by the fact that the distributor contains three identical channels, each of which is formed by the first and second shapers connected by inputs to the synchronization node, and the outputs - with the S-inputs of the first and second RS-flip-flops, the inverse outputs of which are connected to two inputs of the ZI element, and the R-inputs, respectively, with the output of the phase-shifting unit and the delay unit, the third input of the ZI element, the output of which is the channel output the distributor associated with the output of the OR element, connected to the outputs of the phase shifting unit and the delay unit.  % Uc 2.