SU1389959A2 - Multioperator supply system - Google Patents

Abstract

The invention relates to welding production, in particular, to multi-stage power systems for arc welding, and is used in all areas of the national economy where there is a large amount of welding, particularly when installing heat and nuclear power plants. The invention makes it possible to improve the quality of the welded joint. For this multi-post system, the power supply system contains a DC power source, distribution and forward and reverse polarity circuits, groups of direct and reverse polarity current on the electrodes, a current inverter, connecting and switching units, a transformer with a primary and two secondary windings. A master unit installed in the input circuit of the current inverter, and current sensors installed in each of the distribution busbars and connected to the master unit are entered into the system. In this way, the parameters of the current inverter are controlled depending on the current loading of the power supply. 4 il. and

Description

one

The invention relates to welding production, namely to multi station power systems for arc welding, it is applied in all areas of the national economy where there is a large amount of welding work, in particular during the construction of thermal power plants and nuclear power plants and is improved by the invention by auth. No. 1172664.

The aim of the invention is to improve the quality of the welded joint.

Figure 1 is a block diagram of a multi-station power system with one inverter; figure 2 - the same, with two inverters; FIG. 3 is a block diagram of a driver unit for a multiway system with one inverter; 4 is the same for a multi-station power system with two inverters.

Power from a three-phase alternating current network of 380 V is supplied to a DC power supply 1, which can be used as a multi-station power supply for. multi-polar welding.

Distribution busbars 2 and 3, respectively, of reverse and direct polarities are connected to the output terminals A and B of source 1. Inverter 4 current is installed between the busbars, which is connected to the distribution busbar 3 h-through. connecting body 5. for example, automatic switches, knife switches, thyristors, etc. , providing switching on and off of the inverter depending on technological needs or at the output of the inverter. from build. A transformer 6 is installed in the output circuit of the inverter 4, the primary winding of which is connected to the inverter through an anchoring unit 7, providing a pulsating current. As a control unit, a high-frequency diode or a group of diodes connected by a half-wave or bridge rectifier circuit can be used. The secondary winding of the transformer consists of two separate windings 8 and 9, each of which is connected in parallel through its switching unit 10 to the corresponding distribution busbar.

Switching 899592 can be used as a switching unit.

whether, knife switches, etc. The switching unit allows you to connect or disconnect your secondary winding, for example the winding 8 of the transformer 6, without disconnecting the inverter 4, thereby. providing, depending on the technological needs, welding as on direct current with imposing on

10 of it is an inverted pulsating current, and without the imposition of a current. A group of welding stations 11 and 12, respectively, of direct and reverse polarities is connected to distributor busbars by secondary windings 8 and 9 of transformer 6 through switching blocks 10 and connecting blocks 13, for example, circuit breakers, thyristors, etc. .

20 At the output terminals A and B of the power supply source 1 in the distribution busbars 2 and 3, current sensors 14 are installed (for example, reference resistance resistors, relays on

25 magnetically operated contactors, etc.), connected by signal lines 1 5 to the driver unit 16, the output of which is connected to the input of the inverter 4.,

30 Inverters 4 in FIG. 2 are installed between busbars 2 and 3, and to one of them, in this case to bus line 3, they are connected through a common connecting body. To exits

The inverters connected their transformers 6 through their control units 7. The secondary windings of transformers 8 and 9 may have the same number of turns as well.

4Q and connected to their distribution busbars in parallel through their switching units. Between each secondary winding and groups of welding posts, their own

g5 blocks 13 connections.

Driver unit 16 (FIG. 3) consists of a block-adder 17 (for example, a device assembled according to a relay circuit), the output terminals of which are connected to the input terminals of the command-driver unit 18, which can be used, for example, known circuits assembled from relay setting sensors, electronic devices. Output terminals of block 18

50

55

connected to the input terminals of the control elements of the inverter 4.

Dp systems with two or more in-. by drivers, master unit 16 is characterized in that command and control unit 18; (fig.D), in turn, consists of a master block 19 and a command device 20. As block 19, for example, the following cases can be used: positive-adder device for current (voltage), which the received signal in a given the ratio (determined before the start of work) gives the command device 20, which can be used as devices assembled according to relay or electronic circuits.

welding current) regardless of the current load. This ensures the specified technological conditions of the welding process.

The multi-post power system with two inverters (Fig. 2) operates in a similar manner.

The connecting body 5 connects the inverters 4 to the distribution busbars 2 and 3. In this case, depending on the technological needs, the power supply of the groups of welding stations 11 and 12 can be supplied by

roystvo 20 provides control signals with a single current overlaid on it

on individual channels, each current inverter is proportional to the signal applied to its input.

The multipoint power system (Fig. 1) operates as follows.

When the power source 1 is turned on into a three-phase AC network with a voltage of 380 V from the terminals A and B of the power source, the distribution busbars 2 and 3, switching 25 charging units 10 and connecting orblocks 10 and connecting units 13 to the welding stations 11 and 12 groups, supply direct current, respectively, of direct and reverse polarity with a voltage of 95 V. When turned on, the block adder 17 (Fig. 4) is connected, the common signal body 5 to the inverter 4 is supplied with direct current from the power source 1, and to the output circuit Inverter Flows Inverters nny alternating current which via the control unit 7 is converted into a pulsating current. This current, flowing in the primary winding of the transformer 6, induces a corresponding current in its secondary windings 8 and 9, which, when turned on the blocks 10, imposes on a constant current from the power source 1 flowing through the distribution busbars 2 and 3. Power supply to the welding stations 11 and 12 is carried out by switching on blocks 13. With an increase in current load, i.e. with an increase in the number of welding posts connected to the power source 1, the current sensors 14 issue a signal to the driver unit 16, which, in accordance with a given program, sends a command for a proportional increase in the value of the pulsating current 35

The signal from which is fed to the master unit 19J which generates a signal for each inverter in accordance with the magnitude of the received signal and with: a given ratio between the signals on the control lines, i.e. if С is the total signal received at the input, С, and С are the signals of the first and second inverters respectively, then the correlations of the signals С, + Cg С are valid; C,: C K, where K is a predetermined value of the ratio of the signals. The received values of the signals C (and C2 are fed to the command e5 device 20, in which, in strict accordance with the received signals, commands are issued to the input terminals of the control elements of the current inverters 4.

40

50

Tests of a multi-post power supply system showed its operability in terms of TPP installation when changing the current load of a source developed by inverting power supply during a shift from 550 torus 4 current. Thus, it is maintained up to 2,700 A. In this case, the welded joints need depth or stagnation.

They are characterized by high quality and high physicochemical properties.

modulation stub (the ratio of the maximum and minimum amplitudes of the modulated inverted pulsating current from one inverter and direct current with the overlay of inverted pulsating currents from two inverters. At the same time, current B is superimposed on each group of welding stations 6 established their communes 13.

When the current load changes, the signal from the sensors 14 enters the

five

The signal from which is fed to the master unit 19J which generates a signal for each inverter in accordance with the magnitude of the received signal and with: a given ratio between the signals on the control lines, i.e. if С is the total signal received at the input, С, and С are the signals of the first and second inverters respectively, then the correlations of the signals С, + Cg С are valid; C,: C K, where K is a predetermined value of the ratio of the signals. The received values of the signals C (and C2 are fed to the command 5 device 20, in which, in strict accordance with the received signals, commands are issued to the input terminals of the control elements of the 4 current inverters.

0

Tests of a multi-post power supply system showed its operability in terms of TPP installation when the current load of the power source changes during the shift from 550 to 2,700 A. At the same time, the welded connections

They are characterized by high quality and high physicochemical properties.

Claims (1)

Claims of the invention driver unit and current sensors installed in each distribute nominal psnoprovoda, with sensors av.S.№ 1172664, differ- ent-current connected to the inputs of the driver with the fact that, in order to increase the block, the outputs of which are connected to NIN weld quality. the driver unit and current sensors installed in each distribution pnnoprovoda, with sensors current inverter T t 15 7ci AT .BUT usj ju 3 “Up i i.  1-I I-I I-I  J - / 2 c-j OXJ 5615 G 1 eight I ywi L7 3C yj  D .2 // By tsnVertori Fi. sixteen z / ;five X Z / Vv / f in figors FIG.