A V-connection traction transformer

Abstract

The invention discloses a V-connected traction transformer, comprising two single-phase transformer bodies, the two single-phase transformer bodies are placed in a transformer oil tank and fixed, the primary windings of the two transformer bodies are connected in a V shape, the secondary winding of the first transformer body outputs a high voltage, the secondary winding of the second transformer body is composed of 6 independent windings, the first and tail ends of each winding are respectively led out, and 6 low voltages are output; the secondary winding of the body of the device outputs a 27.5kV voltage to power an electric locomotive; the secondary winding of the other body is composed of 6 independent windings, the first and tail ends of each winding are respectively led out, and 6 (3-12) kV voltages are output for a rectifier or a reactive power compensation device, the short-circuit impedance of the 6 secondary windings is exactly the same as that of the primary winding, and the secondary windings can be used alone or in series or in parallel. The V-connected traction transformer provided by the invention is flexible to use and has reliable performance.

Description

Technical Field

[0001] The invention relates to the technical field of transformer equipment, and in particular to a V-connection traction transformer. Background Art

[0002] The traction transformer is used to transmit the electric energy of the three-phase power system to two single-phase traction lines with loads. The two single-phase traction lines supply power to the up and down locomotives respectively. The transformer uses the principle of electromagnetic induction to transfer electric energy or transmit signals from one circuit to another. It is an important component for electric energy transmission or signal transmission. The primary side of the single-phase traction transformer is connected across the two phases of the three-phase power system; one end of the secondary side is connected to the traction side bus, and the other end is connected to the track and the grounding grid. The capacity utilization rate of the single-phase traction transformer is high, but the negative sequence current generated by the single-phase traction load in the power system is large, and the power supply to the contact network cannot be bilaterally supplied. Therefore, this connection is only suitable for occasions where the power system capacity is large, the power grid is relatively developed, and the power consumption of the three-phase load can be reliably supplied by the local power grid.

[0003] At present, the power supply of my country's high-speed electrified railways mostly adopts AT power supply and direct supply. AT power supply usually uses V / X connection traction transformers, and direct power supply usually uses VV connection traction transformers. With the development of high-speed electrified railways, locomotive power continues to increase, and negative sequence and reactive power problems are becoming increasingly prominent. Although the use of phase-changing connection can reduce the negative sequence problem caused by single-phase traction load to a certain extent, and with the assistance of certain reactive power compensation equipment, it can meet the needs of railways, but due to the existence of phase-splitting sections of electrified railways, the locomotive is subjected to discontinuous current, causing considerable train speed and traction loss problems, limiting the development of high-speed railways. According to the needs of the development of high-speed railways, a co-phase power supply system is proposed. The transformer converts the three-phase power system into a two-phase system power supply, one of which is converted into the same phase voltage as the other through a rectifier to jointly supply power to the electric locomotive. In order to reduce equipment investment, one phase of the transformer outputs voltage according to the voltage requirement of the rectifier, and the output voltage also meets the requirements of connecting the reactive power compensation device. When multiple output voltages are required, most existing transformers cannot meet them. Summary of the invention

[0004] The object of the present invention is to provide a V-connected traction transformer to solve the problem that when a same-phase power supply system or a reactive power compensation device requires multiple output voltages, most existing transformers cannot meet the requirements.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0006] A V-connected traction transformer, characterized in that it includes two single-phase transformer bodies, namely a first transformer and a second transformer, the two single-phase transformer bodies are placed in a transformer oil tank and fixed, the primary windings of the two transformer bodies are connected in a V shape, the secondary winding of the first transformer body outputs a high voltage, and the secondary winding of the second transformer body is composed of more than two independent windings, the head and tail ends of each winding are respectively led out, and more than two low voltages are output.

[0007] Furthermore, the first transformer includes a first iron core, a low voltage winding A1, a high voltage winding A1, a low voltage winding A2, and a high voltage winding A2; the two pairs of windings, the low voltage winding A1 and the high voltage winding A1 and the low voltage winding A2 and the high voltage winding A2, are respectively sleeved on the two core columns of the first iron core; the high voltage winding A1 is connected in parallel with the high voltage winding A2 and the terminal A and the terminal B1 are respectively led out at both ends, and the low voltage winding A1 is connected in parallel with the low voltage winding A2 and the terminal a and the terminal x are respectively led out at both ends.

[0008] Furthermore, the second transformer includes a second iron core, two high-voltage windings and two or more low-voltage windings.

[0009] Further, the low voltage winding includes a low voltage winding C1, a low voltage winding C2, a low voltage winding C3, a low voltage winding C4, a low voltage winding C5, and a low voltage winding C6, and the high voltage winding includes a high voltage winding C1 and a high voltage winding C2; the low voltage winding C1, the low voltage winding C3, the low voltage winding C5, the high voltage winding C1 and the low voltage winding C2, the low voltage winding C4, the low voltage winding C6, and the high voltage winding C2 are respectively sleeved on the two core columns of the second core; the high voltage winding C1 is connected in parallel with the high voltage winding C2 and leads to the terminal C and the terminal B2 at both ends; two terminals are set at both ends of the low voltage winding C1, namely the terminal c1 and the terminal z1; two terminals are set at both ends of the low voltage winding C3, namely the terminal c3 and the terminal z3; Two terminals are set at both ends of the low-voltage winding C5, namely terminal c5 and terminal z5; two terminals are set at both ends of the low-voltage winding C2, namely terminal c2 and terminal z2; two terminals are set at both ends of the low-voltage winding C4, namely terminal c4 and terminal z4; two terminals are set at both ends of the low-voltage winding C6, namely terminal c6 and terminal z6.

[0010] Furthermore, the connection terminal B1 of the first transformer is connected to the connection terminal B2 of the second transformer and a connection terminal B is derived.

[0011] Furthermore, the low voltage winding C1, the low voltage winding C3 and the low voltage winding C5 are concentrically arranged in sequence to form a concentric group q1, the terminal z3 is arranged at an end close to the terminal z1, and the terminal c3 is arranged at an end close to the terminal c5.

[0012] Furthermore, the low voltage winding C2, the low voltage winding C4, and the low voltage winding C6 are concentrically arranged in sequence to form a concentric group q2, the terminal z4 is arranged at an end close to the terminal z2, and the terminal c4 is arranged at an end close to the terminal c6.

[0013] Furthermore, the first core is a single-phase stacked core or a wound core; the low voltage winding A1 and the low voltage winding A2 are respectively arranged near the two core columns of the first core, and the high voltage winding A1 and the high voltage winding A2 are respectively arranged on the outside of the low voltage winding A1 and the low voltage winding A2.

[0014] Furthermore, the second core is a single-phase stacked core or a wound core; two concentric groups are respectively arranged near two core columns of the second core, and the high-voltage winding C1 and the high-voltage winding C2 are respectively arranged outside the two concentric groups.

[0015] Furthermore, the high voltage is 27.5 kV, and the low voltage is 3-12 kV.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] The secondary winding of the device body outputs 27.5kV voltage to power the electric locomotive; the secondary winding of the other device body is composed of 6 independent windings, and the first and tail ends of each winding are respectively led out to output multiple (3-12) kV voltages for the rectifier or reactive compensation device. The short-circuit impedance of multiple secondary windings is exactly the same as that of the primary winding, and the secondary windings can be used alone or in series or in parallel. The V-shaped connection traction transformer provided by the present invention is flexible to use and has reliable performance. It can be used for co-phase power supply or reactive compensation of electrified railways or subways with 25kV AC power supply, solving the problem that most existing transformers cannot meet the requirements of co-phase power supply systems or reactive compensation devices when multiple output voltages are required. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is the wiring principle diagram of the present invention.

[0019] Figure 2 This is a schematic diagram of the structure of the present invention.

[0020] In the figure, 1 is the first core A; 2 is the low voltage winding A1; 3 is the high voltage winding A1; 4 is the low voltage winding A2;

[0021] 5—high voltage winding A2; 6—second iron core C; 7—low voltage winding C1; 8—high voltage winding C1; 9—high voltage winding C2; 10—low voltage winding C2; 11—low voltage winding C3; 12—low voltage winding C4; 13—low voltage winding C5; 14—low voltage winding C6. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0023] Embodiment 1:

[0024] A V-connected traction transformer as shown in the figure includes two single-phase transformer bodies, namely a first transformer and a second transformer. The two single-phase transformer bodies are placed in a transformer oil tank and fixed. The primary windings of the two transformer bodies are connected in a V shape. The secondary winding of the first transformer body outputs a high voltage. The secondary winding of the second transformer body is composed of 6 independent windings. The first and tail ends of each winding are respectively led out to output 6 low voltages. The impedance of multiple low-voltage output ends is consistent and can be used in parallel or in series. It can be flexibly used for different output requirements or complex output environments, and has higher adaptability.

[0025] Embodiment 2:

[0026] On the basis of the above embodiments, in this embodiment, the first transformer includes a first core 1, which is a circular cross-section single-phase core made of stacked or rolled silicon steel sheets, and the single-phase core is composed of two core columns and upper and lower iron yokes. The low-voltage winding A12 and the high-voltage winding A13 and the low-voltage winding A24 and the high-voltage winding A25 are respectively sleeved on the two core columns of the first core 1; the high-voltage winding A13 and the high-voltage winding A25 are connected in parallel and lead out the terminal A and the terminal B1 at both ends, respectively, and the low-voltage winding A12 and the low-voltage winding A24 are connected in parallel and lead out the terminal a and the terminal x at both ends.

[0027] Embodiment 3:

[0028] On the basis of the above embodiments, in this embodiment, the second transformer includes a second core 6, which is a circular cross-section single-phase core made of stacked or rolled silicon steel sheets, and the single-phase core is composed of two core columns and upper and lower iron yokes. In order to facilitate the compensation setting, the windings on the second transformer include at least 2 high-voltage windings and 2 or more low-voltage windings, which can be set in detail according to needs. A specific setting method is: the low-voltage winding includes a low-voltage winding C17, a low-voltage winding C210, a low-voltage winding C311, a low-voltage winding C412, a low-voltage winding C513, and a low-voltage winding C614, and the high-voltage winding includes a high-voltage winding C18 and a high-voltage winding C29; the low-voltage winding C17, the low-voltage winding C311, the low-voltage winding C513, the high-voltage winding C18 and the low-voltage winding C210, the low-voltage winding C412, the low-voltage winding C614, and the high-voltage winding C29 The two groups of windings are respectively sleeved on the two core columns of the second core 6; the high-voltage winding C18 is connected in parallel with the high-voltage winding C29 and leads out the terminal C and the terminal B2 at both ends respectively; two terminals are set at both ends of the low-voltage winding C17, namely the terminal c1 and the terminal z1; two terminals are set at both ends of the low-voltage winding C311, namely the terminal c3 and the terminal z3; two terminals are set at both ends of the low-voltage winding C513, namely the terminal c5 and the terminal z5; two terminals are set at both ends of the low-voltage winding C210, namely the terminal c2 and the terminal z2; two terminals are set at both ends of the low-voltage winding C412, namely the terminal c4 and the terminal z4; two terminals are set at both ends of the low-voltage winding C614, namely the terminal c6 and the terminal z6.

[0029] Embodiment 4:

[0030] On the basis of the above embodiment, in this embodiment, the connection terminal B1 of the first transformer is connected to the connection terminal B2 of the second transformer and a connection terminal B is led out.

[0031] Embodiment 5:

[0032] Based on the above embodiments, in this embodiment, the low voltage winding C17, the low voltage winding C311 and the low voltage winding C513 are concentrically arranged in sequence to form a concentric group q1, the terminal z3 is arranged at an end close to the terminal z1, and the terminal c3 is arranged at an end close to the terminal c5.

[0033] Embodiment 6:

[0034] Based on the above embodiments, in this embodiment, the low voltage winding C210, the low voltage winding C412, and the low voltage winding C614 are concentrically arranged in sequence to form a concentric group q2, the terminal z4 is arranged at an end close to the terminal z2, and the terminal c4 is arranged at an end close to the terminal c6.

[0035] Embodiment 7:

[0036] Based on the above embodiments, in this embodiment, the low voltage winding A12 and the low voltage winding A24 are respectively arranged at positions close to the two core columns of the first core 1, and the high voltage winding A13 and the high voltage winding A25 are respectively arranged on the outside of the low voltage winding A12 and the low voltage winding A24.

[0037] Embodiment 8:

[0038] On the basis of the above embodiment, in this embodiment, two concentric groups are respectively arranged at positions close to two core columns of the second core 6, and the high-voltage winding C18 and the high-voltage winding C29 are respectively arranged on the outside of the two concentric groups.

[0039] Embodiment 9:

[0040] On the basis of the above embodiment, in this embodiment, the high voltage is 27.5 kV and the low voltage is 3-12 kV.

[0041] During use, the connection lines of the windings on the concentric group are critical. Series, parallel or cross connection will make the final output of the transformer have different functions. Under the same impedance, parallel connection can reduce the overall impedance, and all series connection will increase the impedance. The specific use should be decided according to the actual output environment.

[0042] The "Example 1", "Example 2", "Example 3", "Example 4", etc. mentioned in this specification refer to the specific features, structures or characteristics described in conjunction with the embodiment included in at least one embodiment generally described in this application. The same expression appearing in multiple places in the specification does not necessarily refer to the same embodiment. Further, when a specific feature, structure or characteristic is described in conjunction with any embodiment, it is claimed that the realization of such feature, structure or characteristic in conjunction with other embodiments also falls within the scope of the present invention.

[0043] Although the present invention is described herein with reference to a number of illustrative embodiments of the present invention, it will be appreciated that those skilled in the art may devise many other modifications and implementations that fall within the scope and spirit of the principles disclosed herein. More specifically, within the scope of the present disclosure, drawings, and claims, a variety of variations and modifications may be made to the components and / or layout of the subject combination layout. In addition to the variations and modifications made to the components and / or layout, other uses will also be apparent to those skilled in the art.

Claims

1. A V-connected traction transformer, Features: It comprises two single-phase transformer bodies, namely a first transformer and a second transformer, the two single-phase transformer bodies are placed in a transformer oil tank and fixed, the primary windings of the two transformer bodies are connected in a V shape, the secondary winding of the first transformer body outputs a high voltage, and the secondary winding of the second transformer body is composed of more than two independent windings, the first and tail ends of each winding are respectively led out, and more than two low voltages are output; The first transformer comprises a first iron core (1), a low voltage winding A1 (2), a high voltage winding A1 (3), a low voltage winding A2 (4), and a high voltage winding A2 (5); the two pairs of windings, the low voltage winding A1 (2) and the high voltage winding A1 (3), and the low voltage winding A2 (4) and the high voltage winding A2 (5), are respectively sleeved on two iron core columns of the first iron core (1); the high voltage winding A1 (3) and the high voltage winding A2 (5) are connected in parallel and lead out a terminal A and a terminal B1 at both ends respectively; the low voltage winding A1 (2) and the low voltage winding A2 (4) are connected in parallel and lead out a terminal a and a terminal x at both ends respectively; The second transformer comprises a second iron core (6), two high-voltage windings and two or more low-voltage windings; The low voltage winding comprises a low voltage winding C1 (7), a low voltage winding C2 (10), a low voltage winding C3 (11), a low voltage winding C4 (12), a low voltage winding C5 (13), and a low voltage winding C6 (14); the high voltage winding comprises a high voltage winding C1 (8), and a high voltage winding C2 (9); the low voltage winding C1 (7), the low voltage winding C3 (11), the low voltage winding C5 (13), and the high voltage winding C1 (8), the low voltage winding C2 (10), the low voltage winding C4 (12), the low voltage winding C6 (14), and the high voltage winding C2 (9) are respectively sleeved on two core columns of the second core (6); the high voltage winding C1 (8) is connected in parallel with the high voltage winding C2 (9) and leads out a terminal C and a terminal B2 at both ends respectively; two terminals are provided at both ends of the low voltage winding C1 (7), namely a terminal c1 and a terminal z1. ; Two terminals are set at both ends of the low-voltage winding C3 (11), namely terminal c3 and terminal z3; Two terminals are set at both ends of the low-voltage winding C5 (13), namely terminal c5 and terminal z5; Two terminals are set at both ends of the low-voltage winding C2 (10), namely terminal c2 and terminal z2; Two terminals are set at both ends of the low-voltage winding C4 (12), namely terminal c4 and terminal z4; Two terminals are set at both ends of the low-voltage winding C6 (14), namely terminal c6 and terminal z6; The connection terminal B1 of the first transformer is connected to the connection terminal B2 of the second transformer and leads to a connection terminal B; The low voltage winding C1 (7), the low voltage winding C3 (11) and the low voltage winding C5 (13) are concentrically arranged in sequence to form a concentric group q1, the terminal z3 is arranged at an end close to the terminal z1, and the terminal c3 is arranged at an end close to the terminal c5; The low voltage winding C2 (10), the low voltage winding C4 (12), and the low voltage winding C6 (14) are concentrically arranged in sequence to form a concentric group q2, the terminal z4 is arranged at an end close to the terminal z2, and the terminal c4 is arranged at an end close to the terminal c6; The first iron core (1) is a single-phase stacked iron core or a wound iron core; the low-voltage winding A1 (2) and the low-voltage winding A2 (4) are respectively arranged at positions close to two iron core columns of the first iron core (1); the high-voltage winding A1 (3) and the high-voltage winding A2 (5) are respectively arranged on the outside of the low-voltage winding A1 (2) and the low-voltage winding A2 (4); The second iron core (6) is a single-phase stacked iron core or a wound iron core; two concentric groups are respectively arranged at positions close to two iron core columns of the second iron core (6), and the high-voltage winding C1 (8) and the high-voltage winding C2 (9) are respectively arranged on the outside of the two concentric groups; The high voltage is 27.5 kV, and the low voltage is 3-12 kV.

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