SU765951A1 - Three-phase voltage regulating device - Google Patents

Description

(54) DEVICE. FOR REGULATING THREE-PHASE VOLTAGE

one

The invention relates to electrical engineering, in particular to converter technology, and can be used, for example, in voltage bias control devices.

A device for controlling three-phase voltage is known, which contains step-down and step-up autotransformers with a common magnetic core, each phase rod of which is made in the form of two half-cores, on which are arranged successive windings interconnected counter-sequentially and common windings connected with successive windings of both autotransformers respectively 1, 2 and 3.

The disadvantages of the known device is low specific energy indicators.

The purpose of the invention is to increase the specific energy indicators of the device by excluding from the circuit of the device special control windings and combining the functions of transformation and control.

The goal is achieved by the fact that the common winding of each phase of both autotransformers consists of two half windings, one of which is made in four equal sections, arranged in pairs on half-cores of the corresponding phase core of the magnetic core and interconnected in a bridge circuit, the input and output of which are formed by common the points of connection of the same and opposite terminals of the sections located on different half-cores, respectively, and the output of each block of control signals are connected to the output of the corresponding bridge circuit. In addition, each phase rod of step-down and step-up autotransformers contains a compensation winding, the conclusions of which are interconnected through a resistor.

The drawing shows the electrical circuit of the device (for clarity,

 only one phase core of common magnetic circuit for step-down and step-up autotransformers).

Claims (3)

The device contains a magnetic core 1, lowering and increasing autotransformers 2 and 3, respectively, successive and phase windings 4, 5 and 6, 7 autotransformers 2 and 3, respectively, sections 8 and 9 of the second half winding of the common windings 6 and 7, respectively, compensation windings 10, 11 , a resistor 12, control signal units 13, 14, a key element and a blocking diode 16 control signal blocks, respectively, a phase control unit 17; input 18, 19, 20 and output 21, 22, 23 of the device, respectively. The principle of operation of the device is as follows. At the highest input voltage, the output signals from the phase control unit 17 to the control signal unit 13 and 14 increase the open state time of the key element 15 of the block 13 and the closed state of the key element 15 of the block 14. Average value of the control current in sections 8 of the common winding 6 is at the same time minimal, and in sections 9 of the common winding 7 is maximum. The step-down autotransformer 2 is almost completely demagnetized, and the step-up autotransformer 3 is magnetized. In this case, the magnetic flux generated by the alternating current is closed through the half-cores of the connected phases, and the magnetic flux generated by the control current is closed through the half-cores of this phase of the autotransformers 2 and 3. General the transformation ratio K K for this Case is almost equal to the transformation ratio of the down-down auto-transformer 2. With a minimum input voltage, the average value of the current yn The avenues in sections 8 of the common winding 6 are maximum, and in sections 9 of the general winding 7 are minimal, and therefore the autotransformer 2 is magnetized and practically does not participate in operation, and the autotransformer 3 is demagnetized and raises the input voltage to the nominal value with the transformation ratio The KzBlocking diodes 16 ensure the separation of the working and controlling half-periods in autotransformers 2 and 3 and the flow of the primary current of autotransformers in the open-time intervals of the key elements 15. Breakdown of Flow 6 (7), common for primary and secondary autotransformer 2 (3) chains and placed on both half-cores and each half-cores of a given phase of the magnetic circuit, is based on the conditions for obtaining the minimum width of the window between the half-cores of one phase and increasing the width of the window between the floors rods of adjacent phases. To balance the magnetic fluxes in the semi-core magnetic circuit of each phase and suppress the four voltage harmonics with respect to the frequency of the supply voltage, as well as to eliminate the positive current feedback of even harmonics in the control objectives, an offset winding 10 is placed on each phase rod of the autotransformers 2 and 3 (11), consisting of two semi-windings interconnected through a resistor 12 in opposite directions. Claim 1. Device for controlling three-phase voltage, containing step-down and step-up autotransformers with a common magnetic circuit, each phase rod of which is formed in the form of two half-cores, on which consecutive windings are located, connected to the secondary windings of both autotransformers, respectively, unit of phase control and control signal blocks, characterized in that, in order to increase the specific energy indicators, the total winding of each phase of both autotransformers The armature consists of two semi-windings, one of which is made in the form of four equal sections arranged in pairs on the half-cores of the corresponding phase core of the magnetic conductor and connected to each other in a bridge circuit, the input and output of which are formed by common connection points of the same section located on different semi-cores, respectively, and the output of each control signal block is connected to the output of the corresponding bridge circuit. 2. A device according to claim 1, characterized in that a compensating winding is arranged on each m phase phase rod of the step-down and step-up autotransformer, the outputs of which are interconnected via a resistor. Sources of information taken into account during the examination 1. SS Perch, etc. Transformer and transformer-thyristor regulators voltage stabilizers. M., “Energie, 1969, fig. 2-6, p. 81. jj 2. USSR author's certificate No.-498610, cl. 605 F 1/14, 1976. 3. USSR author's certificate JVb 534743, cl. 605 Fl /) 4, 1977. 19 18 s, 20