CN201465772U - The structure of a T-connection traction transformer - Google Patents

Abstract

The utility model discloses a structure of a T-shaped wiring traction transformer, which comprises a group of M seat double-column iron cores and a group of T seat double-column iron cores, and the M seat double-column iron cores and the T seat double-column iron cores respectively comprise a high-voltage side winding and a low-voltage side winding. The T-shaped wiring traction transformer is characterized in that the M seat low-voltage side winding and the T seat low-voltage side winding are both connected in series with a voltage regulating winding for connecting each on-load voltage regulating switch, and the M seat low-voltage side winding and the T seat low-voltage side winding are matched with an automatic voltage regulator to realize the automatic voltage regulation of an M seat and a T seat according to load changes. The utility model adopts the structure that two groups of low-voltage windings are separated and connected in series and then two columns are connected in parallel, and a double cake interleaved voltage regulating winding is independently arranged, so that the T-shaped wiring traction transformer has stronger electrically short circuit resisting capability, uniform wave distribution and stable change of each tapping impedance, thereby improving the impact and short circuit resisting capability and the safe reliability of the traction transformer.

Description

The structure of a T-connection traction transformer

technical field

The utility model relates to a new structure of a T-type connection traction transformer. For electrified railway transmission and transformation network.

Background technique

The primary side of the traction transformer has 3 phases, and the secondary side is an independent 2-phase load. There are many types of traction locomotives for electrified railways, with variable loads, large impact loads, and frequent short circuits, which can easily cause unbalanced and large fluctuations in voltage and current in the power grid and substation. Conventional non-excitation T-connection traction transformers cannot automatically adjust the voltage with the change of output load, and the voltage regulation range is small, the tap impedance of the transformer varies greatly, and the impact short-circuit resistance is poor, which cannot meet the diversified traction requirements of the rapid development of electrified railways. Load demand, and tap switching must be powered off, affecting efficiency and power supply quality.

Contents of the invention

The purpose of this utility model is to provide a T-connection low-voltage on-load voltage regulation traction transformer structure to improve the power supply quality of the original high-voltage off-excitation T-connection traction transformer and improve the power supply efficiency of the original traction transformer . The new structure can increase the voltage regulation range of the traction transformer, improve the anti-impact short-circuit capability and safety and reliability of the traction transformer, and reduce the negative sequence current component of the power grid and the voltage and current imbalance in the substation.

In order to achieve the above object, the utility model is realized by taking the following technical solutions:

A structure of a T-connection traction transformer, which consists of two sets of double-column iron cores of an M seat and a T seat, respectively including a high-voltage side winding and a low-voltage side winding, and is characterized in that: both the M-seat and the T-seat low-voltage side windings are connected in series. The voltage regulating windings are connected to their own on-load voltage regulating switches, and used in conjunction with the automatic voltage regulator to realize the automatic adjustment of the voltage of the M seat and the T seat according to the load change.

In the above solution, the high-voltage side winding adopts a tangled-continuous two-column series structure. The low-voltage side winding adopts a two-column parallel structure after splitting two groups in series. The voltage regulating winding is a double pie entangled structure, each pie is connected by a vertical copper rod, and the on-load tap changer and each tap of the voltage regulating winding are connected by a horizontal copper wire. The on-load tap changers and tap windings of the M and T blocks are symmetrically arranged.

The on-load voltage regulation structure of the T-type connection of the utility model sets the voltage regulation on the low-voltage side according to the special working conditions of the traction load, and realizes the automatic adjustment of the voltage of the M seat and the T seat through the voltage regulator according to the load change. Compared with the conventional non-excitation T-connection traction transformer: the on-load voltage regulation is realized, and the voltage regulation range is increased from the original 10% to 48%; because the impedance is 8.4% lower and the deviation is strictly 2×(Z _T -Z _M )/(Z _T +Z _M )<3%, so the low-voltage winding adopts two sets of split series and then two columns in parallel structure, and a double-cake entangled voltage regulating winding is separately set up, which has stronger electrical short-circuit resistance and uniform wave distribution , each tap impedance changes steadily. Improving the anti-impact short-circuit capability and safety reliability of the traction transformer,

Description of drawings

Fig. 1 is the wiring diagram of the utility model.

Figure 2 is a layout diagram of the lead wires of the voltage regulating winding and the on-load tap changer.

In Figure 1 and Figure 2: 10, vertical copper rod; 20, voltage regulating winding; 30, horizontal copper wire; 40, voltage regulating winding head; 50, fuel tank; A, B, C are the high voltage side incoming line terminals connected to the grid ; B, B' and Y, Y' are T-seat high-voltage winding terminals, A, X, C, Z are M-seat high-voltage winding terminals; T _out , t _out , m _out , M _out are low-voltage output terminals connected to the load ; t, t' and T, T' are T-seat low-voltage winding terminals; m, m' and M, M' are M-seat low-voltage winding terminals; Kt, Km are voltage regulating moving contacts; OLTC is on-load voltage regulating switch .

Detailed ways

Below in conjunction with accompanying drawing and embodiment the utility model is described in further detail.

As shown in Figure 1, a low-voltage on-load voltage regulation T-connection traction transformer structure, the voltage regulation range is 48%, and the number of stages is 8. The terminal Y of the high-voltage winding of the T block (phase B) is connected to the middle points X and Z of the high-voltage winding of the M block (phase A and C) to realize the high-voltage 3-phase "T-type" connection, and the phases of the A and C phases are connected with the phases of the B phase. The difference is 90°, and the phase difference between A and C phases is 180°; the low-voltage winding adopts two sets of split series and two-column parallel structure. The interior is a series structure on the double columns; the low-voltage winding m-m' and M-M' of the M seat are two sets of parallel windings after splitting, and the inside of the winding is a series structure on the double columns; The voltage winding is connected in series with the low voltage winding. The on-load pressure regulating switch OLTC is placed on both sides of the fuel tank 50 . The low-voltage winding terminals T, t' are connected with the output terminal T, the low-voltage winding terminals t, T' are connected with the T-seat voltage regulating tap, the T-seat pressure-regulating movable contact Kt is connected with the output terminal t-out; the low-voltage winding terminals M, m' is connected with the output terminal _Mout , the low-voltage winding terminals m and M' are connected with the M-seat voltage regulating tap, and the M-seat voltage-regulating movable contact Km is connected with the _output terminal mout.

As shown in Figure 2, the voltage regulating winding adopts a double-cake tangled structure, the vertical copper rods 10 are used to connect the heads of the pies of the double-cake tangled voltage regulating winding, and the horizontal copper wires 30 are used to connect the taps of the voltage regulating winding. The on-load tap changer O.L.T.C is symmetrically arranged, paying attention to the arrangement and adjustment of voltages at all levels. Due to the orderly, tidy and compact arrangement, it takes up little space and saves cost.

The beneficial effects of the utility model are:

1. The low-voltage winding adopts two sets of split series and then two columns parallel structure, which reasonably controls and distributes the leakage magnetic field and meets the impedance requirements;

2. Separately set up a double-cake tangled voltage regulating winding with a voltage regulating range of 48%. The calculation of voltage gradient and wave distribution is carried out, so that the transformer has a stronger short-circuit resistance ability in electrical design, a more balanced ampere-turn distribution, and a more stable change in the impedance of each tap. It realizes the transformation of T-connection traction transformer from no-load to load, which is in line with the development trend of traction transformer.

3. A symmetrically arranged vacuum on-load tap changer is installed in the low-voltage M block and T block respectively, and the tap leads of the two blocks are arranged symmetrically, orderly, neatly and compactly. It occupies a small space and saves costs, which is of great significance for establishing a conservation-oriented society and sustainable development.

Claims (5)

1. the structure of a T type Connection Traction Transformer, form by the two groups of twin columns iron cores in Building M and Building T, comprise high-pressure side winding and low-pressure side winding respectively, it is characterized in that: all be in series with the pressure regulation winding in the Building M with Building T low-pressure side winding and be connected separately on-load voltage regulating switch.

2. the structure of T type Connection Traction Transformer as claimed in claim 1 is characterized in that: described high-pressure side winding adopts and is entangled with-continous way two post cascaded structures.

3. the structure of T type Connection Traction Transformer as claimed in claim 1 is characterized in that: described low-pressure side winding adopts two components to split series connection back two post parallel-connection structures.

4. the structure of T type Connection Traction Transformer as claimed in claim 1 is characterized in that: described pressure regulation winding is entangled with the formula structure for two cakes, and each cake is lifted one's head by perpendicular copper rod connection, is connected by horizontal copper cash between on-load voltage regulating switch and each tap of pressure regulation winding.

5. the structure of T type Connection Traction Transformer as claimed in claim 4 is characterized in that: the on-load voltage regulating switch of described Building M and Building T and pressure regulation winding are arranged symmetrically.

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