SU1220084A1 - Device for controlling polyphase rectifier converter - Google Patents

Abstract

The invention makes it possible to simplify a device for controlling a multi-phase valve converter.: The device comprises a series-connected synchronization unit 1, a phase-shifting unit 2 and a task unit 6. Moreover, the outputs of blocks 1 and 2 are connected to the outputs of a pulse distributor, the inputs of which are connected to control electrodes of the valves transform- (Vi / Z FIG.

Description

spinner Block 1 consists of three pulse formers 11-13 with direct and inverse outputs, each of which is a comparator controlled by separate inputs. Unit 6 consists of a control voltage source. Distribution1

The invention relates to electrical engineering and can be used in the construction of systems for pulse-phase control of multiphase valve converters at both constant and variable frequency of the power supply network.

The aim of the invention is to simplify the device.

FIG. 1 is a block diagram of a control device; in fig. 2 shows timing diagrams illustrating the operation of the device and the process of generating control pulses for valves connected to the same phase of the mains.

The device contains a synchronization unit 1, a phase shifting unit 2 consisting of the same channels 3-5 according to the number of phases, a task block 6 consisting of a control voltage source, a distributor of pulses 7 containing identical channels 8-10 according to the number of phases.

The synchronization unit 1 consists of three pulse former 11-13 with direct and inverse outputs, each of which is a comparator, controlled by separate inputs.

Channels 3-5 of the phase-shifting unit contain reference voltage drivers 14-16 and comparison elements 17-22. The reference voltage drivers are inverting amplifiers, and the comparison elements are comparators.

The device works as follows.

 The voltages of the three phases A, B, C (diagram 23), synchronized with the mains supplying the converter, are fed to the input of unit 1 and the driver 7 contains identical channels 8-10 by the number of phases. Each channel consists of two groups, the first of which contains element 2I-2I-OR with direct and inverse outputs, and the second - two elements 2OR-NOT. 2 Il. Pulses are converted into a sixth sequence of rectangular pulses corresponding to the positive and negative half-waves of linear voltages AC, BA, CB and AC, BA, CB. Two of them, AC and BA, are shown in diagrams 24 and 25. The obtained sequences are fed to the inputs of the pulse distributor channels and determine the limiting position and pulses of the converter valve control (the valves are numbered in accordance with the order of their entry into operation). The leading fronts of rectangular pulses AC, BA, and CB correspond to the control angle O for the valves of the cathode converter group and the control angle 180 for the valves of the anode group. The leading fronts of rectangular pulses AC, BA, and CB correspond to the control angle O for the valves of the anode group and the angle of control 180 for the valves of the cathode group are transformed.

The determination of the moments of formation of the control pulses is performed in the phase-shifting unit.

The input of the reference voltage generator and the first input of an additional element of comparison of the channel of the phase-shifting unit of this phase receives the voltage of the next phase synchronized with the supply network. At the output of the reference voltage driver, a voltage is generated, antiphase input, which is fed to the first input of another element of the comparison. The forward and antiphase reference voltages for phase AB and B are shown in diagram 26 and for BC and C are shown in diagram 27. To the second inputs of the comparison elements in each channel of the phase shift S12

A controlling block is received. The output voltage from the output of the source voltage of the block 6 of the task is. and at intervals when the reference voltage exceeds the control level, and the outputs of the comparison elements are filled with rectangular pulses CC1, CC4 (diagrams 28 and 29), the position of the leading edges of which determines the moments of switching on the valves connected to this phase of the power supply network. The moment of shutdown of these gates determines the position of the leading edges of rectangular pulses at the outputs of the comparison elements of the channel of the phase-shifting unit of the next CVD phase, CC6 (diagrams 30 and 31).

The distribution of control pulses and their formation by the duration determined by the intervals of the natural conductivity of the valves is carried out by the distributor 7 (Fig. 1).

Each channel of the pulse distributor consists of two groups. The first group contains element 2I-2I-OR with direct and inverse outputs and the second contains two elements 2OR-NOT. At the forward outputs of the elements of the first group of each channel of the pulse distributor, rectangular pulses are formed, the leading fronts of which correspond to the switching on moment of the cathode converter's cathode gates, and the rear ones - to the turning on moment of the anode of the valve. Some of them I1 and IZ are shown in FIG. 2 (diagrams 32 and 33). The logical formulas of the pulses from the direct outputs of the elements of the first group are:

I1 AC CC1 + AC

FROM VA CVD. + VA

I5 CB CVD + SV

The elements of the second group of each distributor channel consist of rectangular pulses from the output of the elements of the first group that generate wide control pulses and distribute them to the converter valves in accordance with the following logic

formulas

PS4

CC4j CCB, CC2.

UI1 I1-f IZ; MUZ IZ + I54 IU5

I1 + IZ; IU6 OF 1 Y5; PS2 I5 + IG.

I5 + I1;

Control pulses for valves connected to phase A IU1, IU4 are shown in FIG. 2 (diagrams 34 and 35).

Thus, the simplification of the device is achieved thanks to a simpler 2008.

nickname of the synchronization block, the task block and the pulse distributor.

Claims (1)

Invention Formula A device for controlling a multiphase valve converter containing a synchronization unit consisting of pulse formers with a number of phases with direct and inverse outputs, inputs of a synchronization unit for connecting phase mains voltages, a phase-shifting unit with a number of channels equal to the number of phases, each which contains a reference voltage driver, the input of which is the input of the channel of the phase-shifting unit and connected to the corresponding input of the synchronization unit, the output side of the reference voltage generator It is connected via the first input of the reference element and the inverter to the output of the channel of the phase-shifting unit, the second inputs of the elements in each channel of the phase-shifting unit are connected to the output of the control voltage source, the outputs of the synchronization unit and the phase-shifting unit are connected to the inputs of the pulse distributor, the outputs of which are intended connection to the control electrodes of the converter valves, characterized in that, in order to simplify the device, the voltage driver is made in the form of invert of the amplifier, each channel of the phase-shifting unit is additionally equipped with a comparison element, the first input of which is connected to the input of the reference voltage conditioner, the second - with the output of the control voltage source, the output of the additional reference element is connected to the input of the pulse distributor, which is made in the form of identical channels by the number of phases, each channel consisting of elements 2I-2I-STI with direct and inverse outputs and two elements 2ILI-NOT, the inputs of one element 2I element 2I-2I-OR of the distributor channel Each phase is connected to the direct output of the corresponding pulse generator of the synchronization unit and with the output of an additional comparison element of the corresponding channel of the phase-shifting unit, the inputs of another element 2I are connected to the inverse output of the same form-j 51 the pulse shifter of the synchronization unit and with the output of the inverter of the same channel of the phase-shifting unit, the direct output of element 2I-2I-OR is connected to the second input of the second element .2OR or HE of the distributor channel of this phase and to the second input of the first ele huHHHHH ZOOOOS 2 25 Au 2200846 2MLI-NOT channel of the distributor of the previous phase, the inverse output of element 2I-2I-OR is connected to the first input of the first element 2IL-NOT of the channel of the distributor of this phase and the first input of the second element of the OR-NOT channel of the distributor of the previous phase. BEHIND 27 - T G one: fC3 f 531 3 .m 35 Editor A; Shandor Compiled by A. Pridatkov Tehred L.Oleynik Proofreader E.Sirohman Order 1329/58 Circulation 631 Subscription VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5 Branch PPP Patent, Uzhgorod, st. Project, 4 X.X : iL 1t // j -IU 2