SU765971A1 - Device for self-excitation of synchronous generator - Google Patents

Description

one

The invention relates to the field of regulating the parameters of a synchronous generator and can be used in constant current installations according to the following scheme: synchronous generator — an uncontrolled rectifier — a direct current electric motor used mainly on commercial and industrial fleets.

A self-excitation system 10 of a synchronous generator is known, consisting of a phase compounding transformer with a selection choke and a semiconductor corrector l. At the same time, the input of the measuring unit of the corrector 5 is connected to the measuring current transformer of the main circuit of the installation, and the power element of the corrector and the control winding of the selection throttle are connected to a constant stabilized voltage source.

However, this system is complex and its performance is not enough.

Closest to the proposed invention is a self-locating-25 system for the synchronous generator, consisting of a phase compounding controlled by biasing the terminals of the transformer with a magnetic shunt separating the voltage and the winding

secondary control and supply windings of the corrector from the current-suppressive and secondary connected via a rectifier to the generator excitation winding, as well as a semiconductor relay-relay corrector semiconductor relay corrector connected to the transformer, the measuring unit of which and the power thyristor forming the correcting circuit with the winding of the corrector, connected, respectively, to the control and supply windings of the compounding transformer 2. Due to the rigid magnetic coupling of these windings with the voltage winding and spec The connection circuit provides a relatively stable periodic supply voltage and a control voltage of the corrector that is ahead of it by 60 electrical degrees.

However, when using a synchronous generator with the indicated excitation system in a constant current installation, when the generator voltage, and therefore the voltage supply voltage of the corrector is destabilized, the normal operation of the corrector becomes impossible. Connecting a corrector to a third-party source of stabilized periodic voltage does not solve the problem due to the fact that the frequencies of the supply and control voltages do not match, since the latter is proportional to the current of the main circuit of the installation. The connection of the power circuit of the corrector to the source of constant voltage is excluded because in this case the power thyristor does not close. The purpose of the invention is to stabilize the current when the generator is operating, through a rectifier to a DC load. This is achieved by the fact that the device for automatically stabilizing the current of the synchronous generator, including the control of the F1 Phase phase compounding transformer with a magnetic shunt separating the winding. current, magnetizing and secondary, connected through, a rectifier to the excitation winding of the generator, and also semiconductor relay-pulse corrector interconnected with transformer the power unit and the power thyristor, which forms the power circuit of the corrector with the magnetic biasing winding, is equipped with a measuring shunt in the direct current load circuit, a three-phase stabilized voltage source and single-phase control and supply voltage transformers that are connected to different phases of the three-phase stabilized voltage source secondary signals, respectively, to the input of the measuring unit and to the power circuit of the corrector, and to the input of the measuring body is also connected Digital shunt in the DC load circuit. To enable the unit to operate at different constant-current settings in the main circuit parallel to the secondary winding of the control voltage transformer, a potentiometer is turned on. . FIG. 2. presents the principle on the scheme of the device for self-excitation or generator in FIG. 2 - curves explaining the operation of the device. The excitation system of the synchronous generator 1 contains a phase compounded transformer 2 controlled by the core magnetization, with a magnetic shunt 3 separating the secondary winding of the control secondary 5 and supplying the correcting winding 6 of the secondary winding 8, magnetizing 8 and the secondary 9 connected through the rectifier 10 to the excitation winding 11, as well as the semiconductor pulse-relay corrector 12, the measuring unit 13 and the power, thyristor 14, which forms the corrector power circuit with the winding 8. To their inputs in a fixed current installation, instead of the disconnected windings 5 and 6 of transformer 2, the secondary windings of the single-phase control transformers 15 and the supply voltage 16 are connected, the primary windings of which are connected respectively to phases А-В and А-С. The input of the unit 13 in series with the secondary circuit of the transformer 15 also includes a current sensor circuit consisting of measuring shunt 17. A potentiometer 18 connected in parallel with the secondary winding of the transformer 15 serves to change the current setting in the circuit of the installation. The device works as follows. When the synchronous generator 1 operates in the constant current mode, the power supply unit 13 and the power circuit of the corrector consisting of the thyristor 14 and the winding 8 are supplied respectively from transformers 15 and 16. The connection of the currents of these transformers according to the diagram in FIG. 1 provides, at the terminals of the secondary windings, a control voltage lagging behind it by 60 electrical degrees, a power supply voltage and. (FIG. 2) A signal proportional to the current in the main circuit of the installation, taken from measuring shunt 17, is summed at the input unit 13 with the voltage is compared with the voltage Uj, which is caused by the zener diode in the circuit of block 13. If the total voltage Ts and more U .., then the zener diode breaks, the output current T comes from the output of the unit 13 / Thyrist Electrode ra 14 and as a result to the winding. 8, the voltage of the positive half-wave U0 is applied. Thus, when the current in the main circuit deviates above the set value, winding 8 carries current, increases the magnetic resistance of the core cores, which leads to a decrease in the EMF of the winding 9 and, eventually, excitation of the generator 1 and restoration of the set current, and when the current deviates below a predetermined value, on the contrary, to the closing of the thyristor, the magnetising of the transformer 2 to the excitation of the generator 1 due to a certain ratio of turns of the primary windings 4.7 and the secondary 9, which provides the initial ix required excitation current, which also leads to the restoration target value of the current in the main circuit. The device expands the functions of the system 1 of self-excitation of a synchronous generator, which allows the generator to be used in installations of a constant toKa. In this case, there is no need to develop and connect a special controller to the generator, does not require significant costs for re-equipment of the existing excitation system, and the possibility of switching the generator to

constant voltage network, which is very significant in connection with the current problem of increasing generator utilization, for example, on ships where a constant current setting and a constant voltage network are common.

Claims (2)

1. A device for self-excitation of a synchronous generator, including a controlled phase compounding transformer with a magnetic shunt separating the voltage winding from the current, a secondary magnet, and a secondary led connected via a straightener to the generator winding, and also connected by means of a ledge diode. a pulse corrector having a measuring unit and a power thyristor forming a corrector power circuit with a magnetic winding, characterized in that, in order to stabilize the current, and the generator operation through a rectifier to a DC load, the device is equipped with a measuring shunt in the DC load circuit, a three-phase stabilized voltage source and single-phase the transformers of the control and supply voltage, the primary windings of which are connected to different phases of the three-phase stabilized voltage source, and the secondary windings respectively to the input of the measuring unit and the power circuit of the corrector, and a measuring shunt in the load circuit is also connected to the input of the measuring unit direct current. Q 2. The device according to claim 1, characterized in that, in order to enable the operation of the installation at different installations of a constant current in the main current, parallel to the secondary winding. 5 control voltage transformers included potentiometer. Information sources, . accepted so attention upon Examination 1.Aronov O. N, Maksimov Yu. I. 0 The use of a series of exciting synchronous generators in rowing electrical installations, m., Shipbuilding, 1966, 7, p. 40-42. 2. Synchronous series generators 5 HMS for 500 and 750 rev / mi. Electric cars. Catalog. Branch VNIIEM on STI in electrical engineering. Moscow, Informelectro, 1973, 11 p., With changes 1 1975, 2 p., No. 2, 1977, p.2. & IAJ | 3 bow AND, 3 (J-t / uH -five