RU166559U1 - STARTING DEVICE ON HIGH VOLTAGE SIDE OF TRANSFORMER SUBSTATION - Google Patents

Abstract

     The proposed technical solution relates to the field of electrical engineering, in particular to electric power systems, and is intended for starting and continuous voltage regulation on the high side of a power transformer.

A control gear on the high voltage side of the transformer substation, containing input and output terminals intended for connecting to the mains and the load, respectively, a power transformer with primary and secondary windings, a three-phase contactor, a three-phase reactor and a three-phase switch made, for example, from two counter-parallel connected thyristors, while the secondary winding of the power transformer is directly connected to the output terminals of the substation, characterized in that the three-phase th switch is connected between the input terminals of the substation and the primary winding of a power transformer and a three-phase reactor via a three-phase contactor connected to three-phase parallel key.

The most appropriate is the use of a device for power transformers of electric arc furnaces in the metallurgical industry, can also be used at transformer substations of enterprises whose consumers require maintaining a stable voltage at a given level.

Description

The proposed technical solution relates to the field of electrical engineering, in particular to electric power systems, and is intended for starting and continuous voltage regulation on the high side of a power transformer.

Known ballasting device for a transformer substation, which is a switchboard solder high-voltage winding of a power transformer by means of a mechanical switch (Bruskin D.E. and others. Electric machines and micromachines: Textbook for electrical engineering special schools: / D.E. Bruskin, A .E. Zorokhovich, V.S. Khvostov. - 3rd ed., Revised and supplemented - M .: Higher school, 1990. - 528 s., Ill., Pp. 70-72, Fig. 2.42 , Fig. 2.43).

The disadvantages of this device are: low reliability and discrete voltage regulation, worsening the dynamic properties of the substation.

It is also known that ballasts (B.N. Sergeenkov, V.M. Kiselev, N.A. Akimova. Electric machines: Transformers: Textbook. A manual for electromechanics. Special universities: Edited by I.P. Kopylov. - M .: Higher School, 1989. - 352 s, p. 290, Fig. 9.6.), Which is taken as a prototype.

The prototype device contains a power transformer, four three-phase thyristor switches, on counter-parallel connected thyristors, a three-phase reactor, a three-phase contactor and a three-phase booster transformer.

However, this device also has disadvantages, which, first of all, include low reliability and discrete voltage regulation.

The technical result of the utility model is to provide continuous voltage regulation under load with increased reliability.

To achieve a technical result, a three-phase switch is connected between the input terminals of the substation and the primary winding of the power transformer, and a three-phase reactor, through a three-phase contactor, is connected to the three-phase switch in parallel. In this case, voltage regulation is ensured practically without a shift of the first harmonic due to the fact that the initial angle of thyristor control α is approximately equal to 90 °.

A diagram of the proposed device is shown in FIG. It contains: input terminals 1, output terminals 2, power transformer 3 with primary winding 4 and secondary winding 5, three-phase thyristor switch 6, three-phase contactor 7 and three-phase reactor 8.

The elements of the device are connected as follows: the input terminals 1 through a three-phase thyristor switch 6 are connected to the primary winding 4, the power transformer 3, and its secondary winding 5 is directly connected to the output terminals 2. In addition, parallel to the three-phase thyristor switch 6, through a three-phase contactor 7, connected three-phase reactor 8.

Many industrial processes require voltage regulation in a given range. In the proposed device, the upper voltage limit is set by setting the primary branch solders 4 of the power transformer 3 to an increased transformation ratio, and the lower limit is determined by the resistance of the reactor 8.

When changing the control angle of thyristors a, three-phase thyristor switch 6, from angle α = φ slightly less than 90 ° to angle α = 150 °, where φ is the angle between voltage and current in the thyristor circuit, regulation is achieved from the maximum voltage level to output terminals 2 to a minimum, or is maintained at a given level when the voltage in the supply network deviates both up and down from the nominal.

The most appropriate is the use of a device for power transformers of electric arc furnaces in the metallurgical industry.

It is also advisable to use enterprises at transformer substations whose consumers require maintaining a stable voltage at a given level, including direct current consumers receiving power from a power transformer through a diode rectifier.

Claims (1)

The control gear on the high voltage side of the transformer substation, containing input and output terminals designed to connect, respectively, to the network and the load, a power transformer, with primary and secondary windings, a three-phase contactor, a three-phase reactor and a three-phase switch, made, for example, from two counter-parallel connected thyristors, while the secondary winding of the power transformer is directly connected to the output terminals of the substation, characterized in that it is three-phase th switch is connected between the input terminals of the substation and the primary winding of a power transformer and a three-phase reactor via a three-phase contactor connected to three-phase parallel key.

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