Traction auxiliary converter and rail transit vehicle

Abstract

The traction auxiliary converter comprises a cabinet body, the cabinet body is sequentially divided into a first cavity, a second cavity and a third cavity which are independent and communicated in the X direction, and the X direction is perpendicular to the running direction of a train; the first chamber is divided into a first upper side chamber and a first lower side chamber along the running direction of the train; a mode switch, a diode, a current-limiting protection device assembly and a first pre-charging unit are arranged in the first upper side cavity; a traction converter module is arranged in the first lower side cavity; the second chamber is provided with a magnetic element, a cooling fan, a transformer and a three-phase alternating current filter; the third chamber is divided into a second upper side chamber and a second lower side chamber along the running direction of the train; the second upper side chamber is provided with a second pre-charging unit and a filter capacitor; and the second lower side chamber is provided with an auxiliary converter module and an output contactor. According to the utility model, high integration of the traction auxiliary converter is realized.

Description

Technical Field

[0001] The utility model relates to the technical field of rail transit equipment, and in particular to a traction auxiliary converter and a rail transit vehicle. Background Art

[0002] As a clean energy, hydrogen fuel cells are gradually being promoted and applied in the field of rail transit. At present, the hydrogen required for hydrogen fuel cells is generally stored in pressure tanks and arranged on the train. At the same time, since the output power of the current hydrogen fuel cells cannot meet the needs of the train's instantaneous high power output, batteries are generally used in parallel. Therefore, the use of hydrogen fuel cells will increase related equipment, which makes the layout space of train equipment tight. Therefore, how to miniaturize the design of traction and auxiliary converters and optimize the main circuit of existing converters to adapt to the use of hydrogen fuel cells has become an urgent problem to be solved in the industry. Utility Model Content

[0003] In order to solve the technical problem of how to design a traction and auxiliary converter in a miniaturized manner, the utility model proposes a traction auxiliary converter and a rail transit vehicle.

[0004] In a first aspect, an embodiment of the utility model provides a traction auxiliary converter, comprising a cabinet, wherein the cabinet is sequentially divided into a first chamber, a second chamber, and a third chamber that are independent and connected along an X direction, wherein the X direction is perpendicular to a traveling direction of a train;

[0005] The first chamber is divided into a first upper chamber and a first lower chamber along the driving direction of the train; a mode switch, a diode, a current limiting protection device assembly and a first pre-charging unit are arranged in the first upper chamber, and a power input cable clamping device is arranged on the outer side of the cabinet corresponding to the first upper chamber; a traction converter module is arranged in the first lower chamber, and a cable clamping device for a motor and a brake resistor is arranged on the outer side of the cabinet corresponding to the lower chamber;

[0006] The second chamber is provided with magnetic elements, a cooling fan, a transformer, and a three-phase AC filter;

[0007] The third chamber is divided into a second upper chamber and a second lower chamber along the travel direction of the train; the second upper chamber is provided with a second pre-charging unit and a filter capacitor, and a control cable connector is provided on the outside of the cabinet corresponding to the second upper chamber; the second lower chamber is provided with an auxiliary converter module and an output contactor, and an AC (AC) cable clamping device and a DC (DC) cable clamping device are provided on the outside of the cabinet corresponding to the second lower chamber.

[0008] Preferably, the current limiting protection device assembly includes a first current limiting protection device, a second current limiting protection device and a third current limiting protection device;

[0009] The input end of the mode switch is connected to the DC power supply of the traction auxiliary converter; the first current limiting protection device and the first pre-charging unit are installed on the connection line between the first output end of the mode switch and the first input end of the traction converter module; the second output end of the mode switch is connected to the second input end of the traction converter module;

[0010] The third output terminal of the mode switch is connected to the A+ node, and the diode that conducts unidirectionally from the mode switch to the A+ node is provided on the connection line between the mode switch and the A+ node; the second current limiting protection device is provided on the connection line between the A+ node and the positive terminal of the vehicle auxiliary bus; the fourth output terminal of the mode switch is connected to the A- node; the A- node is connected to the negative terminal of the vehicle auxiliary bus;

[0011] The third current limiting protection device and the second pre-charging unit are installed on the line between the A+ node and the first input end of the auxiliary converter module; the A- node is connected to the second input end of the auxiliary converter module.

[0012] Preferably, the traction converter module integrates a transmission control unit, a detection unit, a support capacitor, a chopper unit and an inverter unit.

[0013] Preferably, the auxiliary converter module integrates a boost chopper circuit, a resonant converter circuit, an auxiliary inverter circuit, a charger circuit and an auxiliary control circuit.

[0014] Preferably, the first upper chamber and the first lower chamber are connected to each other; the second upper chamber and the second lower chamber are connected to each other.

[0015] Preferably, the traction converter module and the auxiliary converter module are arranged symmetrically.

[0016] Preferably, the first lower chamber and the second lower chamber are respectively provided with air inlets along the X direction; and the second chamber is provided with an air outlet along the traveling direction of the train.

[0017] Preferably, filters are provided at both the air inlet and the air outlet.

[0018] Preferably, the first lower chamber is provided with a first air duct; the second chamber is provided with a second air duct; the second chamber is divided into a fan suction chamber; the first air duct and the second air duct are both connected to the fan suction chamber, and a guide plate is provided at the connection between the air duct and the fan suction chamber.

[0019] Preferably, the connection between the air duct and the fan suction chamber is sealed by a sealing strip.

[0020] Preferably, the magnetic element is arranged in the direction of the main air outlet of the cooling fan.

[0021] Preferably, the cabinet body is provided with a lifting lug.

[0022] A rail transit vehicle comprises the traction auxiliary converter as described above.

[0023] The traction auxiliary inverter and rail transit vehicle provided by the utility model realize the high integration of the traction auxiliary inverter, reduce the overall volume of the traction auxiliary inverter, and miniaturize the design of the traction and auxiliary inverters by respectively arranging the modular components of the traction auxiliary inverter in the chambers of the cabinet. Furthermore, it is installed in the bottom area of ​​the train through the lifting lugs, thereby improving the utilization rate of the space under the train. Furthermore, both the traction inverter module and the auxiliary inverter module adopt a highly integrated solution to realize the miniaturization design of the components in the cabinet. Furthermore, the traction inverter module and the auxiliary inverter module are arranged symmetrically to improve the stress condition of the cabinet structure, and the air duct setting, the position design of the heating elements such as the magnetic element relative to the cooling fan, and the orientation design of the air inlet and the air outlet realize the hierarchical cooling of the heating elements and improve the utilization efficiency of the cooling air. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present utility model and therefore should not be regarded as limiting the scope.

[0025] Figure 1 A schematic diagram of the internal layout of a traction auxiliary converter provided in an embodiment of the utility model;

[0026] Figure 2 A partial schematic diagram of the air duct layout of the traction auxiliary converter provided in an embodiment of the utility model;

[0027] Figure 3 A circuit schematic diagram of a traction auxiliary converter provided in an embodiment of the utility model. DETAILED DESCRIPTION

[0028] The technical scheme in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is only a part of the embodiment of the utility model, rather than all the embodiments. The components of the embodiment of the utility model generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiment of the utility model provided in the drawings is not intended to limit the scope of the utility model claimed for protection, but merely represents the selected embodiment of the utility model. Based on the embodiment of the utility model, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the utility model.

[0029] like Figure 1 As shown, this embodiment discloses a traction auxiliary converter, including a cabinet. The cabinet is divided into a first chamber, a second chamber and a third chamber which are independent and connected in sequence along the X direction, and the X direction is perpendicular to the driving direction of the train.

[0030] The first chamber is divided into a first upper chamber and a first lower chamber along the driving direction of the train. A mode switch, a diode, a current limiting protection device assembly and a first pre-charging unit are arranged in the first upper chamber. A power input cable clamping device is arranged on the outside of the cabinet corresponding to the first upper chamber. A traction inverter module is arranged in the first lower chamber, and a cable clamping device for a motor and a brake resistor is arranged on the outside of the cabinet corresponding to the lower chamber, which is conducive to improving the electromagnetic compatibility performance of the equipment.

[0031] The second chamber is provided with magnetic elements, a cooling fan, a transformer, and a three-phase AC filter, wherein the magnetic elements include reactors and inductor components.

[0032] The third chamber is divided into a second upper chamber and a second lower chamber along the driving direction of the train. The second upper chamber is provided with a second pre-charging unit and a filter capacitor, which can reduce the wiring path length of the period components. A control cable connector is provided on the outside of the cabinet corresponding to the second upper chamber. An auxiliary converter module and an output contactor are provided in the second lower chamber, and an AC cable clamping device and a DC cable clamping device are provided on the outside of the cabinet corresponding to the second lower chamber.

[0033] Through the arrangement of the above-mentioned traction auxiliary converter, part of the power supply energy in the first upper chamber flows to the auxiliary converter module, and the other part flows to the traction converter module, which is conducive to optimizing the problem of concentrated heat caused by the current flowing through a copper busbar. And by arranging the modular components of the traction auxiliary converter in each chamber of the cabinet, the traction auxiliary converter is highly integrated, the overall volume of the traction auxiliary converter is reduced, and the miniaturized design of the traction auxiliary converter is realized. In addition, by arranging the cooling fan in the second side chamber in the middle position, ventilation and heat dissipation of all module devices in the cabinet can be achieved.

[0034] In a preferred embodiment, the first upper chamber and the first lower chamber are interconnected, and the second upper chamber and the second lower chamber are interconnected, which is beneficial to the arrangement of copper bars for connecting components between chambers and the heat dissipation of components.

[0035] In a preferred embodiment, the traction converter module and the auxiliary converter module are symmetrically arranged. The symmetrical arrangement of the two heavier components, the traction converter module and the auxiliary converter module, is conducive to the balanced distribution of the weight of the entire cabinet and improves the stress of the cabinet structure.

[0036] In a preferred embodiment, the first lower chamber and the second lower chamber are provided with air inlets along the X direction respectively; the second chamber is provided with an air outlet along the train running direction. Thus, the cooling air first passes through the first lower chamber and the second lower chamber respectively, cools the traction converter module and the auxiliary converter module, and then cools the heating elements such as the magnetic element, thereby improving the utilization rate of the cooling air. In addition, the air inlet is provided in the X direction, i.e., perpendicular to the train running direction, so as to reduce the influence of the airflow on the cooling air when the vehicle is running.

[0037] In a preferred embodiment, filters are provided at the air inlet and the air outlet, and the filters can filter out larger solid impurities and part of the water in the cooling air to prevent the air duct from being blocked.

[0038] In a preferred embodiment, the first lower chamber is provided with a first air duct. The second chamber is provided with a second air duct. The second chamber is provided with a fan suction chamber. Both the first air duct and the second air duct are connected to the fan suction chamber, and a guide plate is provided at the connection between the air duct and the fan suction chamber. Furthermore, the connection between the air duct and the fan suction chamber is sealed by a sealing strip, which can ensure that the chamber has a certain dustproof and waterproof grade, which is conducive to a more compact arrangement of the components in the cabinet. Among them, the air duct can be set at the top of the component, or it can be set at the bottom of the component, and the specific setting can be based on the specific application. Taking the air duct set at the top of the component as an example, if Figure 2As shown, the cabinet includes a cabinet door 1, and also includes a filter 2 arranged at the air inlet of the first lower chamber and a filter 2 arranged at the air inlet of the second lower chamber. The first lower chamber is provided with a first air duct 3; the second chamber is provided with a second air duct 4; the second chamber is provided with a fan suction chamber 5. The first air duct 3 and the second air duct 4 are both connected to the fan suction chamber 5, and the connection is sealed by a sealing strip 6, and a guide plate 7 is provided at the connection. The guide plate 7 guides the cooling air to the fan suction chamber 5, so that the cooling fan 8 sucks air from the top, and then the cooling air is thrown out in the radial direction of the fan blades through the fan blades of the cooling fan 8. This is to reduce the turbulence of the cooling air in the air duct and reduce the generated aerodynamic noise.

[0039] In a preferred embodiment, the magnetic element is arranged in the main air outlet direction of the cooling fan, and more preferably, the wind resistance of the filter at the air outlet is lowered. Specifically, the wind resistance of the air outlet filter located in the air outlet direction of the cooling fan is lowered, thereby improving the heat dissipation efficiency of the magnetic element.

[0040] In a preferred embodiment, the cabinet is provided with a lifting lug. The traction auxiliary converter is installed at the bottom of the train through the lifting lug on the cabinet, which can make full use of the space under the train and shorten the distance between the lifting lug installation hole and the cabinet to shorten the cantilever length of the lifting lug and improve the force of the lifting lug.

[0041] In a preferred embodiment, if Figure 3As shown, the traction auxiliary converter includes a mode switch, a current limiting protection device assembly, a second pre-charging unit, a traction converter module, a diode, a second pre-charging unit, a filter capacitor, a magnetic element, an auxiliary converter module, a transformer, a three-phase filter and an output contactor, a cooling fan, an A+ node, an A- node and a B node. The magnetic element includes a reactor and an inductor assembly. The current limiting protection device assembly includes a first current limiting protection device, a second current limiting protection device and a third current limiting protection device. The current limiting protection device adopts a fuse or a high-speed circuit breaker, which can quickly disconnect the corresponding fault branch when an overload or grounding occurs in each circuit to reduce the spread of the fault and protect the safe operation of the equipment. The input end of the mode switch is connected to the DC power supply of the traction auxiliary converter, such as a hydrogen fuel cell, a battery and a storage power supply. By switching the connection of the DC power supply of the traction auxiliary converter by the mode switch, three working modes of operation, storage and grounding can be realized, and the positive and negative DC busbars can also be switched synchronously by manual operation or electric drive. When switched to operation, the hydrogen fuel cell and the battery simultaneously supply power to the traction auxiliary inverter. The battery can output or absorb the braking energy of the hydrogen fuel cell and the traction inverter according to the actual working conditions. When switched to storage use, the storage power supply can supply power to the auxiliary inverter and the battery. When switched to grounding, the traction auxiliary inverters are all grounded to ensure reliable grounding of the equipment.

[0042] The first current limiting protection device, the first pre-charging unit and the reactor are installed on the connection line between the first output end of the mode switch and the first input end of the traction converter module. The second output end of the mode switch is connected to the second input end of the traction converter module. Specifically, the first pre-charging unit includes a contactor and a current limiting resistor. For example, the first pre-charging unit includes two parallel branches, one of which is a first contactor and a current limiting resistor in series, and the other includes a second contactor. The first pre-charging unit is used to slowly charge the support capacitor in the traction converter module.

[0043] The third output terminal of the mode switch is connected to the A+ node, and the diode that conducts unidirectionally from the mode switch to the A+ node is provided on the connection line between the mode switch and the A+ node. The second current limiting protection device is provided on the connection line between the A+ node and the positive terminal of the vehicle auxiliary bus. The diode is used to prevent the energy of the vehicle auxiliary bus from being transmitted to the power supply circuit of the traction inverter module. The fourth output terminal of the mode switch is connected to the A- node; the A- node is connected to the negative terminal of the vehicle auxiliary bus.

[0044] The third current limiting protection device and the second pre-charging unit are installed on the line between the A+ node and the first input end of the auxiliary converter module. The A- node is connected to the second input end of the auxiliary converter module. The first output end of the auxiliary converter module is connected to the transformer, and the second output end of the auxiliary converter module is connected to the three-phase filter. The output end of the three-phase filter is connected to an output contactor, and the output end of the output contactor is connected to an AC cable clamping device. The third output end of the auxiliary converter is connected to a DC cable clamping device.

[0045] Therefore, the A+ node and the A- node are the common power nodes of the auxiliary converter modules of the whole vehicle, so as to ensure that if a battery or hydrogen fuel cell fails during operation, and when the storage power supply is only supplied by one storage socket, the auxiliary converter modules of the whole vehicle can work normally.

[0046] In a preferred embodiment, if Figure 3 As shown, the traction converter module integrates a transmission control unit, a detection unit, a support capacitor, a chopper unit, an inverter unit and a first power board. The miniaturization design of the traction converter module is achieved by rationally integrating the above circuits.

[0047] The transmission control unit is used to realize the control and protection functions of the traction converter module according to the feedback signals from the detection unit, pre-charging unit, chopper unit, inverter unit, cooling fan control unit, etc. and the instructions sent by the vehicle, for example, including controlling the first pre-charging unit to slowly charge the support capacitor.

[0048] The detection unit is used to detect the temperature signal, voltage signal and current signal required for the control function and protection function of the traction auxiliary converter.

[0049] The chopper unit is composed of controllable semiconductor devices and is used in conjunction with the brake resistor to consume electric brake feedback energy and suppress excessive voltage of the intermediate capacitor.

[0050] The inverter unit includes a three-phase bridge arm integrating a three-phase inverter circuit. The inverter unit is used to invert DC power into three-phase AC power with adjustable frequency and amplitude, and drive the motor to work. It is also used to rectify the three-phase AC power into DC power during electric braking, and feed energy back to the battery and the intermediate capacitor.

[0051] The first power supply board is used to convert the DC110V power supply into several voltage levels to supply power to the drive circuits of the transmission control unit, the detection unit, the chopper unit and the inverter unit.

[0052] In a preferred embodiment, if Figure 3As shown, the auxiliary converter module integrates a boost chopper circuit, a resonant converter circuit, an auxiliary inverter circuit, a charger circuit, an auxiliary control circuit and a second power board. The miniaturization design of the auxiliary converter module is achieved by rationally integrating the above circuits.

[0053] The boost chopper circuit is used to boost low voltage direct current to provide stable power supply for the resonant converter circuit. The boost chopper circuit includes a reactor component.

[0054] The resonant converter circuit is used to achieve electrical isolation of input and output. The resonant converter circuit includes a full-bridge inverter circuit, a capacitor, a transformer, and a rectifier circuit.

[0055] The auxiliary inverter circuit is used to invert the DC power output by the resonant converter into AC380V power, and then output it to the outside through a three-phase filter. The auxiliary control unit controls the output contactor closed loop to realize the input and disconnection of the three-phase AC power.

[0056] The charger circuit is used to convert the resonant output power into DC110V through a DC\DC converter (referring to a switching power supply chip) for use in train control.

[0057] The second power supply board is used to convert the DC110V power supply into several voltage levels to supply power to the boost chopper circuit, the resonant converter circuit, the auxiliary inverter circuit, the charger circuit, and the drive circuit of the auxiliary control circuit.

[0058] The traction auxiliary inverter provided by the utility model realizes high integration of the traction auxiliary inverter by arranging the modular components of the traction auxiliary inverter in the chambers of the cabinet respectively, reduces the overall volume of the traction auxiliary inverter, and performs miniaturized design of the traction and auxiliary inverters. Furthermore, it is installed in the bottom area of ​​the train through the lifting lugs, thereby improving the utilization rate of the space under the train. Furthermore, both the traction inverter module and the auxiliary inverter module adopt a highly integrated solution to realize the miniaturized design of the components in the cabinet. Furthermore, the traction inverter module and the auxiliary inverter module are arranged symmetrically to improve the stress condition of the cabinet structure, and the air duct setting, the position design of the heating elements such as the magnetic element relative to the cooling fan, and the orientation design of the air inlet and the air outlet realize the hierarchical cooling of the heating elements and improve the utilization efficiency of the cooling air.

[0059] In addition, the utility model also provides a rail transit vehicle, including the aforementioned traction auxiliary inverter, wherein the traction auxiliary inverter is the traction auxiliary inverter disclosed in the above embodiment. Therefore, the rail transit vehicle with the traction auxiliary inverter also has all the above technical effects, which will not be repeated here.

[0060] In the several embodiments provided in the embodiments of the present utility model, it should be understood that the disclosed device and method can also be implemented in other ways. The device and method embodiments described above are only illustrative.

[0061] It should be noted that, in this article, the terms "first", "second", etc. in the specification and claims of the utility model and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. The terms "comprises", "includes" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprises a..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0062] Although the implementation methods disclosed in the utility model are as above, the above contents are only the implementation methods adopted for facilitating the understanding of the utility model, and are not used to limit the utility model. Any technician in the technical field to which the utility model belongs can make any modifications and changes in the form and details of the implementation without departing from the spirit and scope disclosed in the utility model, but the scope of patent protection of the utility model shall still be based on the scope defined in the attached claims.

Claims

1. A traction auxiliary converter, characterized in that: The cabinet comprises a cabinet body, wherein the cabinet body is sequentially divided into a first chamber, a second chamber and a third chamber which are independent and connected along an X direction, wherein the X direction is perpendicular to the running direction of the train; The first chamber is divided into a first upper chamber and a first lower chamber along the driving direction of the train; a mode switch, a diode, a current limiting protection device assembly and a first pre-charging unit are arranged in the first upper chamber, and a power input cable clamping device is arranged on the outer side of the cabinet corresponding to the first upper chamber; a traction converter module is arranged in the first lower chamber, and a cable clamping device for a motor and a brake resistor is arranged on the outer side of the cabinet corresponding to the lower chamber; The second chamber is provided with magnetic elements, a cooling fan, a transformer, and a three-phase AC filter; The third chamber is divided into a second upper chamber and a second lower chamber along the driving direction of the train; the second upper chamber is provided with a second pre-charging unit and a filter capacitor, and a control cable connector is provided on the outside of the cabinet corresponding to the second upper chamber; the second lower chamber is provided with an auxiliary converter module and an output contactor, and an AC cable clamping device and a DC cable clamping device are provided on the outside of the cabinet corresponding to the second lower chamber.

2. The traction auxiliary converter according to claim 1, characterized in that: The current limiting protection device assembly includes a first current limiting protection device, a second current limiting protection device and a third current limiting protection device; The input end of the mode switch is connected to the DC power supply of the traction auxiliary converter; the first current limiting protection device and the first pre-charging unit are installed on the connection line between the first output end of the mode switch and the first input end of the traction converter module; the second output end of the mode switch is connected to the second input end of the traction converter module; The third output terminal of the mode switch is connected to the A+ node, and the diode that conducts unidirectionally from the mode switch to the A+ node is provided on the connection line between the mode switch and the A+ node; the second current limiting protection device is provided on the connection line between the A+ node and the positive terminal of the vehicle auxiliary bus; the fourth output terminal of the mode switch is connected to the A- node; the A- node is connected to the negative terminal of the vehicle auxiliary bus; The third current limiting protection device and the second pre-charging unit are installed on the line between the A+ node and the first input end of the auxiliary converter module; the A- node is connected to the second input end of the auxiliary converter module.

3. The traction auxiliary converter according to claim 2, characterized in that: The traction converter module integrates a transmission control unit, a detection unit, a support capacitor, a chopper unit and an inverter unit.

4. The traction auxiliary converter according to claim 2, characterized in that: The auxiliary converter module integrates a boost chopper circuit, a resonant converter circuit, an auxiliary inverter circuit, a charger circuit and an auxiliary control circuit.

5. The traction auxiliary converter according to claim 1, characterized in that: The first upper chamber and the first lower chamber are communicated with each other; the second upper chamber and the second lower chamber are communicated with each other.

6. The traction auxiliary converter according to claim 1, characterized in that: The traction converter module and the auxiliary converter module are arranged symmetrically.

7. The traction auxiliary converter according to claim 1, characterized in that: The first lower chamber and the second lower chamber are respectively provided with air inlets along the X direction; and the second chamber is provided with an air outlet along the traveling direction of the train.

8. The traction auxiliary converter according to claim 7, characterized in that: Filters are provided at the air inlet and the air outlet.

9. The traction auxiliary converter according to claim 7, characterized in that: The first lower chamber is provided with a first air duct; the second chamber is provided with a second air duct; the second chamber is provided with a fan suction chamber; the first air duct and the second air duct are both connected to the fan suction chamber, and a guide plate is provided at the connection between the air duct and the fan suction chamber.

10. The traction auxiliary converter according to claim 9, characterized in that: The connection between the air duct and the air suction chamber of the fan is sealed by a sealing strip.

11. The traction auxiliary converter according to claim 8, characterized in that: The magnetic element is arranged in the main air outlet direction of the cooling fan.

12. The traction auxiliary converter according to claim 1, characterized in that: The cabinet body is provided with a lifting lug.

13. A rail transit vehicle, characterized in that: It comprises a traction auxiliary converter as claimed in any one of claims 1 to 12.

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