CN209297901U - a traction transformer - Google Patents

Abstract

The utility model provides a traction transformer, which belongs to the technical field of AC electrified railway power supply. In the two-phase winding, between terminals X1 and X3 at both ends of one phase winding, lead to the middle tap terminal X2, and between terminals Y1 and Y3 at both ends of the primary side of the other phase winding, at 0.866 times the total number of turns of the winding based on Y3 Lead out the tap terminal Y2, that is, three terminals on each of the primary sides of the two windings are independently led out to the outside of the transformer. After the terminals X3 and Y1 on the primary side are connected, they are respectively connected to the three-phase voltage of the power system with the terminals X1 and Y3, and the other terminals are suspended. a and the traction load of power supply arm b. After the terminals X2 and Y2 on the primary side are connected, the terminals X1, X3, and Y3 are respectively connected to the three-phase voltage of the power system, and the other terminals are suspended. When the traction transformer is working on the Scott connection, the two ports on the secondary side respectively supply power to two independent The tractive loads of arm a and arm b are powered.

Description

a traction transformer

technical field

The utility model belongs to the technical field of AC electrified railway power supply.

Background technique

At present, in the traction power supply system of electrified railway, it is the main part of electric energy transformation. The traction transformer can adopt different wiring methods to meet different needs, and the traction transformers with different wiring methods also have their own characteristics in performance. However, the current traction transformer only considers a specific connection method during manufacture, and only this connection method can be used in the life cycle. If a traction transformer can form different wiring modes, it can meet the needs of different traction substations. In addition, with the development of railway operations, in order to adapt to the changing operational needs, it is necessary to carry out certain transformations and upgrades on existing lines. During the renovation process, traction transformers were decommissioned because their capacity did not meet the requirements. How to make full use of traction transformers that have not reached the upper limit of their service life is of great significance for improving the economy of the traction power supply system.

As the main part responsible for power conversion in the traction power supply system, the traction transformer directly affects the operation status of the traction power supply system. Currently used Vv wiring traction transformers have two terminals on each of the primary sides of the two-phase windings, and one terminal of each phase winding is connected inside the transformer. Three-phase connection, the two ports on the secondary side output two different line voltages with a phase difference of 60° or 120°, which supply power to two independent traction loads respectively; Scott wiring traction transformers have two terminals in one phase winding, and the other phase Except for the first and last two terminals of the winding, the middle tap is drawn out, which is connected to one terminal of the two-terminal winding. Only three terminals are drawn out from the primary side to connect with the three phases A, B, and C of the power system, and the two terminals on the secondary side are output Two different line voltages with a phase difference of 90° supply power to two independent traction loads respectively.

Existing traction transformers only consider a specific connection method during manufacture, and only this connection method can be used in the life cycle. In order to meet the needs of users for traction transformers with different wiring methods, different production lines are required, which takes up more human and material resources. In addition, with the development of railway operations, in order to adapt to the changing operational needs, it is necessary to carry out certain transformations and upgrades on existing lines. During the reconstruction process, the traction transformer was decommissioned because the capacity did not meet the requirements. In order to make full use of the service life of the transformer, the traction transformer that has not reached the service life limit can be used in other traction substations, but the traction substations must adopt the same The wiring method is very limited. If the same traction transformer can be configured with different wiring methods, it can not only meet the needs of different users, but also simplify the production line and improve production efficiency; at the same time, it can also reduce the limitations of the scope of use and better utilize the service life of the traction transformer.

Utility model content

The purpose of this utility model is to provide a traction transformer, which can effectively solve the technical problem that the same transformer constitutes a Vv wiring traction transformer or a Scott wiring traction transformer by changing the external wiring, and meets the requirements of different traction substations for traction transformer wiring. need.

The utility model solves the problems of the technologies described above, and the adopted technical solution is:

A traction transformer: including a three-phase iron core and two-phase windings, the three-phase iron core is determined according to the requirements of the Vv connection traction transformer for the iron core, the two-phase windings are respectively arranged on the iron core columns on both sides of the three-phase iron core, and the two In the phase winding, at the middle position between the X1 terminal and the X3 terminal at the two ends of the primary side of the X-phase winding, the middle tap terminal X2 is drawn out, and between the Y1 terminal and the Y3 terminal at the two ends of the primary side of the Y-phase winding, taking the Y3 terminal as the reference , the tap Y2 terminal is drawn at 0.866 times the total number of turns, that is, the primary sides of the X and Y windings each have three terminals and are independently drawn to the outside of the transformer; The X1 terminal on the primary side of the X-phase winding, the X3 terminal on the primary side of the X-phase winding, and the Y3 terminal on the primary side of the Y-phase winding are connected to the three-phase power system. The X3 terminal on the primary side of the X-phase winding is connected to the Y1 terminal on the primary side of the Y-phase winding, and the X2 terminal , Y2 terminals are suspended in the air; the two ports on the secondary side supply power to the traction loads of power supply arm a and power supply arm b separately; when the traction transformer works in the Scott connection operation state, the X1 terminal of the X-phase winding primary The X3 terminal on one side and the Y3 terminal on the primary side of the Y-phase winding are connected to the three-phase power system, the X2 terminal on the primary side of the X-phase winding is connected to the Y2 terminal on the primary side of the Y-phase winding, the Y1 terminal is suspended, and the two terminals on the secondary side are One-way power supply arm a, power supply arm b traction load power supply.

The primary sides of the X and Y windings each have three terminals that are independently led to the outside of the transformer, and the Vv connection mode or the Scott connection mode is formed by changing the external wiring.

The working principle of the utility model is:

The primary side of the Vv-connected traction transformer and the Scott-connected traction transformer are both connected to the three-phase voltage of the power system, but due to the different terminal connection methods, the voltage difference between the two-phase windings of the Vv-connected traction transformer is 60° or 120°, and the Scott-connected traction transformer is two-phase The voltages of the windings differ by 90°. By leading out the middle tap of one phase winding and changing the terminal connection mode, the requirements of the Vv connection traction transformer and the Scott connection traction transformer for the voltage phase of the two windings can be met.

The transformation ratios of the primary and secondary sides of the two-phase windings of the Vv connection traction transformer are the same, while the transformation ratio of one phase winding of the Scott connection traction transformer is the same as that of the Vv connection traction transformer, and the transformation ratio of the other phase winding is different from that of the Vv connection traction transformer . Therefore, the other phase winding that does not lead to the middle tap is led to the tap at 0.866 times the total number of winding turns, and the terminal connection mode can be changed to achieve different transformation ratios, which can meet the winding transformation ratio of Vv connection traction transformer and Scott connection traction transformer different requirements.

When the traction transformer constitutes Vv connection or Scott connection by changing the external connection, the operation status of the transformer is different, which is mainly reflected in the difference in the superposition result of the core magnetic flux. Due to the different phase relationship of the voltage connected to the primary side, the magnetic flux passing through the middle phase iron core column in the Vv connection operation state is greater than the magnetic flux passing through the intermediate phase iron core column in the Scott connection operation state. The magnetic flux of the core column where the winding is located is related to the voltage connected to the primary side of the winding and the number of coil turns contained in the winding. Therefore, the magnetic flux of the core columns on both sides of the traction transformer is consistent in the Vv connection operation state and the Scott connection operation state, and should be Taking the maximum value of the magnetic flux of the iron core when the Vv wiring traction transformer is formed as the limit value, the effective cross-sectional area of the transformer iron core can be determined to avoid magnetic saturation of the iron core, and the traction transformer can work normally in the running state of Vv wiring or Scott wiring. state.

Compared with the prior art, the beneficial effects of the utility model are:

1. The utility model can work in two states, Vv connection and Scott connection. One traction transformer can meet the different requirements of different traction substations for the traction transformer connection mode, and has a wide range of applications.

Two, the utility model can be carried out on the basis of existing technology, can not increase the difficulty on the craft and can not increase material cost.

3. The utility model can simplify the production line and improve the production efficiency while maintaining the applicability and richness of the product.

4. The utility model is applied in the construction of new lines without increasing the construction investment; when the line is reconstructed, it can make full use of the equipment that has not reached the upper limit of service life, change the wiring mode of the traction transformer to meet different needs, and give full play to the life of the traction transformer, which is economical Good sex.

Description of drawings

Fig. 1 is a schematic diagram of the winding terminal of the utility model.

Fig. 2 is a schematic diagram of the Vv wiring mode of the utility model.

Fig. 3 is a schematic diagram of the Scott connection mode of the utility model.

Fig. 4 is a schematic diagram of the iron core, winding arrangement and magnetic flux distribution of the utility model.

Detailed ways

Embodiments The utility model will be further described below in conjunction with the accompanying drawings and specific embodiments.

Figure 1 shows that a specific embodiment of the present invention is: a traction transformer: comprising a three-phase iron core and a two-phase winding, the three-phase iron core is determined according to the requirements of the Vv wiring traction transformer for the iron core, and the two-phase winding They are respectively arranged on the iron core columns on both sides of the three-phase iron core. In the two-phase winding, at the middle position between the X1 terminal and the X3 terminal at the two ends of the primary side of the X-phase winding, the middle tap X2 terminal is drawn out, and on the primary side of the Y-phase winding. Between the Y1 terminal and Y3 terminal at both ends of the side, with the Y3 terminal as the reference, the tap Y2 terminal is drawn at 0.866 times the total number of turns, that is, the primary sides of the X and Y windings each have three terminals and are independently drawn out to the outside of the transformer ; When the traction transformer works in the Vv connection running state, the X1 terminal on the primary side of the X-phase winding, the X3 terminal on the primary side of the X-phase winding, and the Y3 terminal on the primary side of the Y-phase winding are connected to the three-phase power system, and the primary side of the X-phase winding The X3 terminal of the Y-phase winding is connected to the Y1 terminal on the primary side of the Y-phase winding, and the X2 terminal and the Y2 terminal are suspended; the two terminals on the secondary side supply power to the traction loads of the power supply arm a and the power supply arm b respectively; when the traction transformer works in Scott wiring state, the X1 terminal of the primary side of the X-phase winding, the X3 terminal of the X-phase winding primary side, and the Y3 terminal of the Y-phase winding primary side are connected to the three-phase power system, and the X2 terminal of the X-phase winding primary The Y2 terminal of the terminal is connected, the Y1 terminal is suspended, and the two ports on the secondary side supply power to the traction load of the power supply arm a and power supply arm b respectively.

The primary sides of the X and Y windings each have three terminals that are independently led to the outside of the transformer, and the Vv connection mode or the Scott connection mode is formed by changing the external wiring.

Figure 2 shows the Vv connection mode of the traction transformer in the embodiment of the utility model. After the primary terminals X3 and Y1 are connected, they are respectively connected to the three phases A, B, and C of the power system with the terminals X1 and Y3, and the remaining terminals are suspended, and the traction transformer works. In the Vv connection running state, the two ports on the secondary side supply power to the traction loads of the two independent power supply arms a and b respectively.

Figure 3 shows the Scott connection mode of the traction transformer in the embodiment of the present invention. After the primary terminals X2 and Y2 are connected, the terminals X1, X3, and Y3 are respectively connected to the three phases A, B, and C of the power system, and the remaining terminals are suspended. The traction transformer Working in the running state of Scott connection, the two ports on the secondary side supply power to the traction loads of two independent power supply arms a and power supply arm b respectively.

Fig. 4 is a schematic diagram of the iron core, winding arrangement and magnetic flux distribution of the embodiment of the present invention. The two-phase windings are respectively arranged on the iron core columns on both sides of the three-phase iron core.

Claims (2)

1. A traction transformer: including a three-phase iron core and two-phase windings, the three-phase iron core is determined according to the requirements of the Vv connection traction transformer for the iron core, and the two-phase windings are respectively arranged on the iron core columns on both sides of the three-phase iron core , characterized in that: in the two-phase winding, at the middle position between the X1 terminal and the X3 terminal at the two ends of the primary side of the X-phase winding, the middle tap X2 terminal is drawn out, and between the Y1 terminal and the Y3 terminal at the two ends of the Y-phase winding primary side , based on the Y3 terminal, lead out the tap Y2 terminal at 0.866 times the total number of turns, that is, each of the primary sides of the X and Y windings has three terminals and are independently led out to the outside of the transformer; when the traction transformer is working in the Vv wiring operation state , the X1 terminal on the primary side of the X-phase winding, the X3 terminal on the primary side of the X-phase winding, and the Y3 terminal on the primary side of the Y-phase winding are connected to the three-phase power system, and the X3 terminal on the primary side of the X-phase winding is connected to the Y1 terminal is connected, X2 terminal and Y2 terminal are suspended; the two ports on the secondary side supply power to the traction loads of power supply arm a and power supply arm b respectively; when the traction transformer works in the Scott connection operation state, X1 terminal, X3 terminal on the primary side of the X-phase winding, and Y3 terminal on the primary side of the Y-phase winding are connected to the three-phase power system, the X2 terminal on the primary side of the X-phase winding is connected to the Y2 terminal on the primary side of the Y-phase winding, the Y1 terminal is suspended, The two ports on the side supply power to the pulling loads of power supply arm a and power supply arm b respectively. 2. A traction transformer according to claim 1, characterized in that: the primary sides of the X and Y windings each have three terminals that are independently led to the outside of the transformer, and the Vv wiring mode or Scott is formed by changing the external wiring. Wiring.