SU1103341A1 - Device for adjusting current-parametric thyristor converter - Google Patents

Abstract

1. A DEVICE FOR CONTROLLING A CURRENT-METER THYRISTOR TRANSMITTER, made of two counter-parallel m-phase thyristor bridges connected to a high-voltage AC network through a parametric current source containing a distributor and a separate control unit, a direct and inverse output, a direct and inverse output, a direct output and an inverse output, a direct output terminal and an inverse output of the direct voltage generator. to the first inputs of the distributor, and the outputs of the latter are intended to be connected, to the control circuits of the thyristors, a block for setting the duration of the zero load current connected to the second in The distributor's home, 4t of zero-organs, each of which is intended to connect the input parallel to the power electrodes of the corresponding thyristor, and the output to the corresponding third distributor input, characterized in that, in order to extend the functionality by providing an inverter mode of the current-variable valve converter, it is equipped the source of the inverting signal, 4 tons of delay elements included at the output of each null organ, the distributor is supplied with 4 tons additional The inputs and signal of the inversion signal, the outputs of the delay elements are connected to the additional inputs of the distributor, and the distributor contains 2 tons of 2 OR, 4 OR, 2 AND elements, and also 4 tons of DI and 4I elements, each output of the distributor designed to control the odd thyristors of the first bridge and even the thyristors of the second bridge, connected to the output of the corresponding element 2 OR, the inputs of which are connected to the outputs of the first elements ZI and 4I, with the first input of each pepper element ZI connected to the corresponding the second input and the third, with the first and second inputs of the first elements 4I and the first inputs of the distributor, the third inputs of the first elements 4I are connected to the corresponding additional inputs of the distributor, and the fourth to the output of the inverting signal source, each output of the distributor designed for controlling the even thyristors of the first bridge and the odd thyristors of the second bridge, is connected to the output of the corresponding 4IL element, whose inputs are connected to the outputs of the 2I elements and the second element ZI and 4I, as well as with the second CO input of the distributor, the first one with the input of each specified element ZI connected with the corresponding third input of the distributor, and the second and third with the first and second inputs of the second elements 4I, with the first and second inputs of the elements 2I and with the first inputs of the distributor, the third input of each specified element 4I is connected to the corresponding additional input of the distributor, and the fourth to the input of the inversion signal.

Description

The invention relates to electrical engineering and can be used in control systems for valve converters.

A device for controlling a current-parameter valve converter (TSTD), consisting of two anti-parallel t-phase thyristor sets connected at the output of a three-phase parametric current source, containing a pulse distributor and output amplifiers 1, is known.

A disadvantage of the known device is the impossibility of implementing the inverter mode.

The closest is a device for controlling a current-parametric thyristor converter made of two anti-parallel t-phase thyristor bridges connected to a hp-phase ac voltage network through a parametric current source containing a distributor and a separate control unit, direct and inverse outputs which are connected to the first inputs of the distributor, and the outputs of the latter are intended to be connected to the control circuits of the thyristors, the block setting the duration of the zero load current, with Connected to the second input of the distributor, 4 tons of nullorgans, each of which is connected by its input in parallel to the power electrodes of the corresponding thyristor, and the output to the corresponding third input of the distributor 2.

The disadvantage of this device is the absence of an inverter mode of operation, which is necessary, for example, when braking a direct current electric drive.

The purpose of the invention is to expand the functionality by introducing an inverter operation mode.

The goal is achieved by the fact that a device for controlling a current-parametric thyristor converter made of two counter-parallel T-phase thyristor bridges connected to a T-phase AC network through a parametric current source containing a distributor and a separate control unit, direct and the inverse outputs of which are connected to the first inputs of the distributor, and the last of the inputs of the latter are intended for connection to the control circuits of the thyristors, the block for setting the duration to zero, and the loads connected to the second input of the distributor, 4b zero-bodies, each of which is connected to the power electrodes of the corresponding thyristor, and output to the corresponding third input of the distributor, 4 m delay elements connected to the output of each null organ, the distributor is equipped with 4sh additional the inputs and the input of the inverting signal, the outputs of the delay elements are connected to the additional inputs of the distributor, and the distributor contains 2 tons of elements 2 OR, 4IL, 2I, as well as 4 tons of elements ZI and 4I, and dy distributor output for controlling the first bridge tristorami odd and even second thyristor bridge connected to the output OR element 2, whose inputs are connected to outputs of the first elements

0 ЗИ and 4И, with the first input of each first element of the ЗИ connected to the corresponding third input of the distributor, and the second and third - with the first and second inputs of the first elements 4I and the first inputs of the distributor, the third inputs of the first elements 4И, are connected to the corresponding additional inputs of the distributor, and the fourth to the output of the inverting signal source, each output. the distributor, designed to control the even thyristors of the first bridge and the odd thyristors of the second bridge, is connected to the output of the corresponding OR element 4, the inputs of which are connected to the outputs of the 2 And elements and the second And 3 And 4 elements, as well as

5 of the distributor, with the first input of each specified element 3 And connected with the corresponding third input of the distributor, and the second and third with the first and second inputs of the second elements 4 And, with the first and second inputs of the elements 2 And and with the first inputs of the distributor, the third input each specified element 4 AND is connected to the corresponding additional input of the distributor, and the fourth to the input of the inversion signal.

, FIG. 1 shows a block diagram of a device for controlling, for example, a three-phase converter; in fig. 2 - single-phase converter circuit; in fig. 3 - time diagrams of his work when inverting the ideal EMF; on

0 fig. 4 - schematic diagrams that implement the output signals of the distributor.

Device for controlling a current-parameter thyristor converter 1 made of two anti-parallel valve kits connected

To the alternating voltage network through a parametric current source 2, and supplying the load 3 from the internal emf, contains a distributor 4 pulses and a separate control unit 5, the forward M and inverse N outputs of which are connected to the distributor 4, and the outputs of the latter are connected to control circuits mi thyristors. If the load 3 has significant inductance, such as a permanent machine

current, then a voltage capacitor 6 is connected in parallel to the output of the UTIL terminal. The signals at the output of unit 5 take values in accordance with the following table: Name of operating mode M N Positive current in load 1 O Negative current in load O 1 Zero current in load O O The device also contains block 7 sets the duration of the zero load current 3, generating a Z signal, as well as nullorgans 8–19, delay elements 20–31, source 32 of the inversion signal R, connected by an output to one of the inputs of the distributor 4, and valve kits, tion of thyristors 33.1-33.6 and 34.1 - 34.6. Each of the above zero-bodies 8-19 is connected by its input to the power electrodes of the corresponding thyristor 33.1-33.6 and 34.1-34.6, and the output to the distributor 4 and to the corresponding delay element 20-31. Output signals A.:. BI. .. delay elements 20-31 are supplied to other inputs of the distributor 4 Each odd control channel of the distributor 4 contains element 3 AND 35 and element 4 AND 36 connected to the inputs of element 2 OR 37. Each odd control channel consists of elements 3И35, element 4 And 36 and element 2 And 38, KOTOpbie are connected to the inputs of element 39. The device operates as follows. With a low level of signals at the output of block 7 and source 32 and the presence of an appropriate combination of signals M and N at the output of block 5, valve 4 produces control signals Wf to turn on, for example, thyristors 33.1 and 33.6. Turning on thyristors 331-33 will occur at natural points opening by synchronizing signals Xi-Hb, .. coming from zero-bodies 8-13 direct voltage anode-cathode on thyristors 33i g ЗЗе ... After switching on thyristors 331 7 ЗЗф in load 3 a current of positive direction is established. The duration of the control signal generated by the valve 4 is determined by the duration of the synchronization signal, which disappears after switching on the next thyristor, since. the voltage drop across the conductive valve is not sufficient to maintain the corresponding zero-organ in the on state. This allows minimizing the thyristor control power of the converter. The reverse of the current in load 3 starts when the block 5 is switched. The next thyristor will start operation from the second set according to the synchronization signal of its null organ. Next, the thyristors 34i-34e. Of the second set come into operation in a cyclical order according to the synchronization signals of the null organs 14-19. To regulate the output current of the converter of any polarity, the current is transferred to the time determined by block 7 from the load circuit to short-circuited circuits created by the thyristors 33.2, 33.4 and 33.6 of the first set, and also by the thyristors 34j 34j and 34s of the second set. The thyristor control algorithms developed by the distributor 4 are described by the following generalized logical equations Wzi-t Xii, tMNVPu iMN Wji Xtj MN VySuMNRVZVMN, Wjt-i X i-iMN -tMNR VZ VMN, Wzi. 3, ..., (the last number in the row is determined by the number of thyristors in one set); Xi, Xi .. are synchronization signals generated by the thyristor voltage 33.1-33.6 and 34.1-34.6; ) 5j, i- ANGLES to invert the thyristors of the first and second sets. To convert the converter into the mode of inverting the energy of the load 3, the signal R 1 is fed from the output of the source 32 to one of the distributor 4 inputs. Depending on the direction of the current previously flowing in the load 3, the first 33 or the second 34 set of thyristors. The above algorithms for the operation of the distributor 4 are compiled for the inversion mode as applied to the DC current, i.e. for load 3, the internal emf of which is directed oppositely to the current when the converter is in the rectifying mode. Consequently, conversion of the converter to the inverter mode is carried out without changing the polarity of the internal emf of the load 3. The inverter mode is implicit using the example of a single-phase TSTD substitution circuit when inverting the ideal EMF EQ (Fig. 2). FIG. 3 shows time diagrams of currents, voltages and conduction angles of thyristors. When indicated in FIG. 3 of the EO polarity, the role of the main thyristors plays Vi-V |, and the role of the additional ones - Vt V. If the polarity of the EO changes to the opposite, then the functions of the thyristor sets also change. From the timing diagrams, it follows that the main thyristors, Vj-V, turn on their valve properties during the intervals J3. Under the action of the voltage drop across the auxiliary thyristors Vt-Vi, which are locked under the action of E when the next main thyristor is opened. Angle,. measured from the point of natural unlocking of the thyristor, is determined by the delay elements 20-31 and should not be less than the limit inversion angle / mir, which, in turn, is determined by the turn-off time of the thyristor. FIG. 3, the angle is only large for clarity.

The application of the described device allows to provide an inverter mode of operation of the converter, to extend the functionality.

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Claims (2)

1. DEVICE FOR CONTROL OF A CURRENT-PARAMETRIC THYRISTOR CONVERTER made of two counter-parallel m-phase thyristor bridges connected to an m-phase AC voltage network through a parametric current source containing a distributor and a separate control unit, the direct and inverse outputs of which are connected to the first inputs the distributor, and the outputs of the latter are designed to be connected _ to the control circuits of the thyristors, the unit for setting the duration of the zero load current connected to the second input a distributor, 4t of zero-organs, each of which is designed to connect the corresponding thyristor by an input parallel to the power electrodes, and the output to the corresponding third input of the distributor, characterized in that, in order to expand functionality by providing an inverter mode of a current-variable valve converter, it is equipped with a source inverting signal, [4t delay elements included at the output of each zero-organ, the distributor is equipped with 4t additional inputs and the inversion signal,] the outputs of the delay elements are connected to additional inputs of the distributor, and the distributor contains 2t elements 2 OR, 4 OR, 2 AND, as well as 4 t of ZI and 4I elements, each output of the distributor designed to control the odd thyristors of the first bridge and even thyristors of the second bridge is connected to the output of the corresponding 2 OR element, the inputs of which are connected to the outputs of the first elements ZI and 4I, while the first input of each first element of ZI is connected to the corresponding third input of the distributor, and the second and third -. with the first and second inputs of the first 4I elements and the first inputs of the distributor, the third inputs of the first 4I elements are connected to the corresponding additional inputs of the distributor, and the fourth to the output of the invert signal source, each output of the distributor is designed to control even thyristors of the first bridge and odd thyristors of the second bridge connected to the output of the corresponding element 4 OR, the inputs of which are connected to the outputs of the elements 2I and the second elements ZI and 4I, as well as with the second input of the distributor, pr this, the first input of each specified element of the ZI is connected with the corresponding third input of the distributor, and the second and third with the first and second inputs of the second elements 4I, with the first and second inputs of the elements 2I and with the first inputs of the distributor, the third input of each specified element 4I is connected to the corresponding with an additional input to the distributor, and the fourth with the input of the invert signal.