Circuit breaker for locomotive, high-voltage electric appliance combined equipment and locomotive

Abstract

The invention discloses a circuit breaker for a locomotive, high-voltage electric appliance combination equipment and the locomotive, and belongs to the technical field of high-voltage electric appliances, the circuit breaker for the locomotive comprises a supporting chain, a container is arranged outside the supporting chain, a kinematic chain is arranged in the supporting chain, and the supporting chain comprises a lower supporting insulating cylinder, a movable end conductive part and an upper supporting insulating cylinder which are connected in sequence; the kinematic chain comprises an insulating pull rod, an insulating pull rod insert and a conducting rod which are connected in sequence, an open hole is formed in the moving-end conducting part, and the lower supporting insulating cylinder is communicated with an inner cavity of a corrugated pipe of the vacuum arc-extinguishing chamber to form a normal-pressure air chamber; a high-pressure air chamber is formed between the supporting chain and the container; an outer shield is arranged in the high-pressure air chamber, and one end of the outer shield is fixed on the movable end conductive piece. And the electric field intensity of the inner surfaces of the insulating pull rod and the lower support insulating cylinder in the normal-pressure air chamber is improved, so that the insulation of the whole high-voltage electric appliance combination equipment reaches an ideal level.

Description

Technical Field

[0001] The present invention belongs to the technical field of high-voltage electrical appliances, and in particular relates to a circuit breaker for a locomotive, a high-voltage electrical appliance combination device and a locomotive. Background Art

[0002] An electric locomotive generally refers to a vehicle that uses a pantograph to obtain electrical energy from the contact network and converts this electrical energy into traction. For example, electric trains, EMUs, and high-speed trains in the prior art all belong to electric locomotives. In the prior art, the electrical energy obtained by the pantograph needs to pass through a high-voltage system including high-voltage disconnectors, voltage transformers, vacuum circuit breakers, grounding switches, current transformers and other high-voltage devices before entering the interior of the electric locomotive. In order to ensure that there is no electrical interference between these high-voltage components, these high-voltage devices are all arranged on the top of the electric locomotive, directly connected by high-voltage cables or high-voltage copper bars, and a predetermined electrical safety distance is maintained between any two high-voltage devices. However, all system components are directly exposed to the air. Therefore, these high-voltage devices are easily affected by external climatic conditions such as rain, snow, ice, and haze, resulting in discharge to the ground. At the same time, they are easily affected by external rain, fog, dirt, airflow, and ultraviolet light environments, resulting in breakdown or discharge, which seriously affects the operation safety of the EMU. Moreover, the outer insulation material of the high-voltage components on the roof is mostly made of silicone rubber. After the high-voltage components are contaminated, they must be cleaned and washed every time they are returned to the warehouse. This cleaning will have a serious impact on the hydrophobicity of the silicone rubber material, which will directly affect the electrical performance of the high-voltage components. At the same time, the predetermined electrical safety distance between these high-voltage devices is relatively far, requiring a large space, and the space on the top of the electric locomotive is very narrow, making the installation and removal of these high-voltage devices very inconvenient.

[0003] The main function of the high-voltage system of the locomotive is to obtain single-phase AC25kV high-voltage electricity from the contact network, provide power for the train, and realize the main functions of power supply, electrical protection, and monitoring of network voltage and working current. Once the high-voltage system of the EMU fails such as discharge, it will cause the EMU to be delayed and passengers to be stranded. In serious cases, it will also cause the entire contact network power supply to be cut off, thereby affecting the operation of the entire line. Therefore, ensuring the safety and reliability of the EMU high-voltage system is directly related to the operational safety of the EMU.

[0004] In order to solve the above problems, the most common method is to integrate all these high-voltage system components into a high-voltage box. However, this box is generally a normal pressure environment and is not sealed. The internal environment is easily polluted, and the pressure inside and outside the box is easily inconsistent when running at high speed. This situation is very destructive to the welding gap of the box. In addition, the steel-welded box is thicker to ensure strength, and the weight of the entire box is larger, which does not meet the requirements of lightweight design. At the same time, air insulation is currently mainly used in the box to ensure its internal insulation performance, but the product volume required by the air insulation structure is large, which does not meet the requirements of miniaturization and lightweight design. In order to ensure the internal insulation volume, it may not even meet the requirements of the vehicle boundary.

[0005] At the same time, the high-voltage electrical equipment of the locomotive must include a vacuum interrupter. The bellows in the vacuum interrupter are usually thin-walled components made of stainless steel with a thickness of 0.1mm-0.2mm. The material and structural characteristics of the bellows determine that its allowable withstand pressure is limited. When the pressure of the insulating medium is too high, it may exceed the allowable withstand pressure of the bellows. The bellows are easily damaged when working in an environment above the allowable withstand pressure for a long time, which in turn affects the service life of the vacuum circuit breaker. The mechanical life of the vacuum interrupter for the locomotive must reach 250,000 times. For conventional bellows, in order to achieve such a long life requirement, the bellows of the vacuum interrupter must work in a normal pressure working environment to ensure the service life requirements when the process, materials, design, etc. have been optimized.

[0006] Specifically, for example, the utility model patent with publication number CN218876910U, "An internally insulated high-voltage system and train", provides an internally insulated high-voltage system and train, the core of which is to wrap the vacuum circuit breaker, disconnector, voltage transformer and second lightning arrester with insulating materials, and to build the high-voltage live parts into the components to achieve internal insulation, without considering external insulation. This method still cannot solve the impact of the external environment on the high-voltage components. Another example is the invention patent with publication number CN103594953 A, "An electric locomotive GIS high-voltage box", which provides an electric locomotive GIS high-voltage box, which integrates high-voltage devices into a square box, and the box is filled with SF6 to ensure external insulation. When the locomotive is running at high speed, especially when entering an environment such as a cave, the air pressure difference between the inside and outside of the box will change significantly, which will have a direct impact on the welding gap of the box, and may cause SF6 leakage and other problems, resulting in a decrease in the insulation level in the box, affecting the operation of the locomotive. For example, the utility model patent "High-voltage switch integrated box" with publication number CN205016909U and the patent "Locomotive high-voltage electrical box" with publication number CN211151326U both integrate the high-voltage devices in the locomotive group into a square box, and insulate the outside of the high-voltage devices. The entire box is still insulated by air. When the locomotive is running in a high-altitude area, the square box with insulation coating and air insulation cannot meet the pressure resistance requirements with air insulation, thus affecting the reliability of locomotive operation. The invention patent "A tank circuit breaker" with publication number CN109801808A is a double-chamber design, and both place the insulating pull rod in the low air chamber. This placement method does not take into account the electric field problem of the end of the insulating pull rod and the inner wall of the insulating cylinder that forms the low air chamber. Summary of the invention

[0007] The present invention provides a circuit breaker for locomotive, a high-voltage electrical assembly and a locomotive, which improve the electric field strength of the insulating pull rod in the atmospheric pressure chamber and the inner surface of the lower supporting insulating cylinder, so that the insulation of the entire high-voltage electrical assembly reaches an ideal level.

[0008] In order to achieve the above object, the present invention adopts the following technical solution: In a first aspect, the present invention provides a circuit breaker for a locomotive, comprising a support chain, a container is arranged outside the support chain, a motion chain is arranged inside the support chain, the support chain comprises a lower support insulating cylinder, and the motion chain comprises an insulating pull rod and a conductive rod fixedly connected; the lower support insulating cylinder and the inner cavity of the bellows of the vacuum arc extinguishing chamber are connected to form a normal pressure air chamber; a high-pressure air chamber is formed between the support chain and the container; an external shield is arranged inside the high-pressure air chamber.

[0009] Furthermore, the outer shielding comprises a cylinder, both ends of the cylinder are open, and one end has a flange.

[0010] Furthermore, the flange at the opening is turned outward.

[0011] Furthermore, the distance between the outer shield and the moving end conductive member is 40% to 60% of the shortest distance between the moving end conductive member and the shell cover.

[0012] Furthermore, the inner diameter of the outer shield is 1.3-1.6 times the outer diameter of the lower supporting insulating cylinder.

[0013] Furthermore, the inner diameter of the outer shield is 1.5 times the outer diameter of the lower supporting insulating cylinder.

[0014] Furthermore, the container includes a shell and a shell cover that are fixedly connected. Furthermore, when the switch is opened, the distance between the insulating pull rod insert and the lower end surface of the outer shield is greater than the distance between the lower end of the outer shield and the lower end surface of the movable end conductive member. In a second aspect, the present invention provides a long-life tank locomotive high-voltage electrical assembly device, including the above-mentioned locomotive circuit breaker.

[0015] In a third aspect, the present invention provides a locomotive comprising the above-mentioned tank locomotive high-voltage electrical assembly equipment. Compared with the prior art, the present invention has at least the following beneficial technical effects: In the present invention, a long-life tank-type locomotive high-voltage electrical assembly equipment is designed, in which high-voltage devices are integrated in a closed container, and an external shield is designed in the high-voltage gas chamber to solve the problem of electric field concentration on the surface of the insulating rod in the normal-pressure gas chamber and the inner surface of the lower supporting insulating cylinder, thereby improving the overall insulation performance of the product; and through the matching design of the external shield, the metal shell, and the lower supporting insulating cylinder, the electric field strength on the surface of the insulating rod in the normal-pressure gas chamber and the inner surface of the insulating rod insulating cylinder can be optimized, thereby improving the insulation level of the entire circuit breaker, and at the same time making the bellows of the vacuum arc extinguishing chamber work in a normal-pressure environment, so as to achieve the long-life performance requirement of 250,000 times of opening and closing.

[0016] At the same time, the circuit breaker described in the present invention adopts a double air chamber to solve the problem that the vacuum arc chamber bellows is easily damaged when exposed to high air pressure, so that the bellows works under normal pressure, providing a guarantee for the realization of a long-life vacuum arc chamber.

[0017] Furthermore, the flange arranged at the opening is turned outward, and in the vacuum circuit breaker, the outer space is larger, and it is easier to balance the size of the flange and the size of the outer shield and the lower supporting insulating cylinder.

[0018] Furthermore, the outer shielding includes a cylinder having a bottom plate at one end, a through hole for passing the lower supporting insulating cylinder, and an opening at the other end. The flange not only improves the electric field distribution, but also enhances the mechanical strength and durability of the shielding cover.

[0019] Furthermore, the container of the present invention includes a shell and a shell cover that are fixedly connected. The shell is an integrally formed structure without welds, and the internal environment is not easily polluted. Even if the pressure inside and outside the box is inconsistent during high-speed operation, the shell will not be damaged, thereby ensuring the stability of product operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of the structure of the long-life tank locomotive high-voltage electrical equipment assembly of the present invention; Figure 2 It is a schematic diagram of the structure of the atmospheric pressure air chamber of the present invention; Figure 3 This is a schematic diagram of the high-pressure gas chamber structure of the present invention; Figure 4 It is a three-dimensional schematic diagram of the outer shielding of the present invention; Figure 5 This is a schematic diagram of the installation position of the outer shielding of the present invention.

[0021] Symbols and descriptions of the accompanying drawings: 1. Insulating rod, 2. Lower supporting insulating cylinder, 3. Shell, 4. External shielding, 5. Moving end conductive part, 6. Upper supporting insulating cylinder, 7. Vacuum arc extinguishing chamber, 8. Insulating rod insert, 9. Sealing ring, 10. Shell cover, 701, bellows, A, normal pressure air chamber, B, high pressure air chamber, 11. Conductive rod, 12. Sealing part. DETAILED DESCRIPTION

[0022] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0023] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0024] It should be noted that when an element is referred to as being "disposed on" another element, it may be directly on the other element or there may be another element centered thereon. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be another element centered thereon at the same time. The terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside", etc. used herein indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0026] Explanation of relevant terms Electric locomotive: usually refers to a vehicle that uses a pantograph to obtain electrical energy from the contact network and converts this electrical energy into traction. For example, electric trains, EMUs, and high-speed trains in existing technologies are all electric locomotives.

[0027] Vacuum interrupter: As a key component of the circuit breaker to extinguish the arc, it cooperates with the operating mechanism to form the breaking capacity, and changes a certain point in the power grid from the current conduction state to the current disconnection state.

[0028] Normal pressure air chamber: an air chamber that is directly connected to the air.

[0029] High air chamber: gas channel with inflation pressure of 0.4-0.8MPa.

[0030] Example 1 Reference Figure 1The present invention designs a tank locomotive high-voltage electrical equipment combination device, which integrates all high-voltage system components in a closed container formed by a shell 3 and a shell cover 10. The shell 3 is a metal tank container, and the shell 3 is an integrally formed structure, which is opened by a mold and has no welds. A connecting boss is extended inward at one end where the shell 3 and the shell cover 10 are connected, which increases the contact area between the shell 3 and the shell cover 10 without increasing the thickness of the shell, and a sealing ring 9 is installed at the connection between the connecting boss and the shell cover 10 to improve the sealing performance and effectively prevent gas leakage or penetration from the connection. The sealing ring can adapt to the pressure and temperature under different working environments and maintain good sealing performance. The shell cover 10 and the sealing member 12 are fixedly connected, and the inner wall of the sealing member 12 is connected to the outer wall of the lower supporting insulating cylinder 2, and multiple sealing rings 9 are arranged at the connection. The shell 3 is filled with environmentally friendly gas with a high pressure greater than 0.5MPa as the internal insulating medium. Compared with air insulation, the high-pressure environmentally friendly gas requires a smaller insulation gap, which can not only meet the insulation requirements, but also ensure the requirements of miniaturization and lightweight design.

[0031] In order to meet the requirements of long life, the circuit breaker in the high-voltage electrical combination equipment is a double-chamber structure, so that the bellows of the vacuum arc extinguishing chamber is placed in a separate normal pressure (or even negative pressure) air chamber, but this double-chamber structure makes the insulating rod 1 and the inner surface of the lower supporting insulating cylinder 2 forming the air chamber channel also located in the normal pressure (or even negative pressure) air chamber, and the required insulation level cannot be achieved. Therefore, in the invention, an external shielding structure is designed in the circuit breaker with a double-chamber structure, and the application of the external shield 4 can effectively improve the electric field strength of the insulating rod and the inner surface of the lower supporting insulating cylinder, balance the electric field, and the relationship between the balanced electric field and the insulation level.

[0032] Example 2 Reference Figures 1 to 4 The present embodiment provides a vacuum circuit breaker for locomotives, including an insulating rod 1, a lower supporting insulating cylinder 2, a shell 3, an outer shield 4, a moving end conductive member 5, an upper supporting insulating cylinder 6, a vacuum arc extinguishing chamber 7, an insulating rod insert 8 and a shell cover 10.

[0033] The insulating rod 1 is connected to the first end of the insulating rod insert 8 by threading, and the second end of the insulating rod insert 8 is connected to the conductive rod 11 of the vacuum arc chamber 7, forming a motion chain of the entire circuit breaker. The vacuum arc chamber 7 is connected to the second end of the insulating rod insert 8, and the insulating rod insert 8 passes through the movable end conductive part 5 and is connected to the middle part of the movable end conductive part 5 to form a conductive chain of the entire circuit breaker. The lower support insulating cylinder 2 is fixedly connected to the movable end conductive part 5 and the upper support insulating cylinder 6 to form a support chain of the entire tank circuit breaker, and multiple sealing rings 9 are provided at the connection. A part of the lower support insulating cylinder 2 is located in the shell 3, and the other part extends out of the shell 3. The vacuum arc chamber 7 is located in the upper support insulating cylinder 6. The outer periphery of both ends of the upper support insulating cylinder 6 is provided with an electric shield. The shell 3 needs to be grounded when the tank circuit breaker is in a working environment, so its potential is the ground potential.

[0034] like Figure 2 As shown, the insulating pull rod 1 is placed in the lower supporting insulating tube 2, and an opening is provided on the moving end conductive part 5. Normal pressure air can reach the inside of the bellows 701 of the vacuum arc extinguishing chamber 7 through the opening on the moving end conductive part 5. The cavity A includes the cavity between the motion chain and the supporting chain and the inner cavity of the bellows. In the working state, the cavity A is filled with normal pressure air, so it is called a normal pressure air chamber.

[0035] The insulating pull rod 11 may have an shed or may not have an shed. A structure without an shed is preferred.

[0036] like Figure 3 As shown, a cavity B is formed between the support chain composed of the lower support insulating cylinder 2, the moving end conductive member 5 and the upper support insulating cylinder 6 and the closed container. The cavity B is filled with a gas insulating medium with a pressure greater than 0.5MPa. The gas insulating medium can be any one of clean air, nitrogen, carbon dioxide or a mixture of C4F7N and carbon dioxide, sulfur hexafluoride gas, etc. It is preferred to use environmentally friendly gases with no greenhouse effect or low greenhouse effect. When the gas is discharged into the atmosphere, it will not increase or decrease the concentration of greenhouse gases, thereby helping to protect the environment. In the working state, the cavity B contains high-pressure gas, so it is called a high-pressure gas chamber. The high-pressure gas chamber and the normal-pressure gas chamber are sealed by multiple sealing rings 9. An outer shield 4 is arranged in the high-pressure gas chamber, and one end of the outer shield 4 is fixed to the outer peripheral surface of the moving end conductive member 5.

[0037] like Figure 4 As shown, the outer shield 4 includes a cylinder 41 with two ends opened, one end of the cylinder 41 is provided with an arc-shaped flange 42, and the end of the outer shield 4 without the flange is fixedly connected to the moving end heat dissipation bracket 16. The flange 42 can not only enhance the mechanical strength and durability of the shielding cover, but also improve the electric field distribution.

[0038] The arc-shaped flange 42 can be turned outward or inward. Preferably, the flange is turned outward so that the flange 42 is located in a larger area, which can provide a better heat dissipation space for the outer shield 4, which helps to reduce the temperature of the outer shield 4, improve the heat dissipation efficiency, and reduce the thermal stress concentration inside the device, thereby extending the service life of the outer shield 4.

[0039] The outer shield 4 is made of metal.

[0040] like Figure 5 As shown, the shortest distance L1 between the moving end conductive part 5 and the shell cover 10, and the distance L2 between the outer shield 4 and the moving end conductive part 5 should satisfy the relationship: L2=(0.4-0.6)×L1, and the preferred relationship is: L2=0.5×L1, so that the end of the outer shield 4 and the shell cover 10 maintain a certain distance in the axial direction. The outer diameter D1 of the lower supporting insulating cylinder 2 and the inner diameter D2 of the outer shield 4 satisfy the relationship: D2=(1.3-1.6)×D1, so that the outer shield 4 protects the inner wall of the insulating pull rod 2 while maintaining a certain distance from the lower bushing 10 in the circumferential direction, preventing the outer shield 4 from having an adverse effect on the lower bushing 10; the preferred relationship is: D2=1.5×D1. The distance L3 between the lower end of the outer shield 4 and the insulating pull rod insert 8 should satisfy the relationship: L3>L2.

[0041] Example 3 This embodiment provides an electric locomotive, comprising the tank locomotive high-voltage electrical equipment assembly device described in Embodiment 1. The circuit breaker in the tank locomotive high-voltage electrical equipment assembly device is the vacuum circuit breaker described in Embodiment 2.

[0042] The term "consisting of" describing a combination shall include the identified elements, ingredients, parts or steps and other elements, ingredients, parts or steps that do not substantially affect the basic novel characteristics of the combination. The use of the terms "comprising" or "including" to describe a combination of elements, ingredients, parts or steps herein also contemplates embodiments that consist essentially of these elements, ingredients, parts or steps. By using the term "may", it is intended to illustrate that any of the attributes described that "may" be included are optional.

[0043] Multiple elements, ingredients, parts or steps can be provided by a single integrated element, ingredient, part or step. Alternatively, a single integrated element, ingredient, part or step can be divided into separate multiple elements, ingredients, parts or steps. The disclosure "one" or "an" used to describe an element, ingredient, part or step is not intended to exclude other elements, ingredients, parts or steps.

[0044] It should be understood that the above description is for illustration and not for limitation. Many embodiments and many applications beyond the examples provided will be apparent to those skilled in the art upon reading the above description. Therefore, the scope of the present teachings should not be determined with reference to the above description, but rather with reference to the foregoing claims and the full scope of equivalents to which such claims are entitled. For the purpose of comprehensiveness, all articles and references, including disclosures of patent applications and publications, are incorporated herein by reference. The omission of any aspect of the subject matter disclosed herein in the foregoing claims is not intended to be a waiver of such subject matter, nor should it be considered that the applicant has not considered such subject matter to be part of the disclosed inventive subject matter.

Claims

1. A circuit breaker for locomotive, characterized in that: It comprises a support chain, a container is arranged outside the support chain, a motion chain is arranged inside the support chain, the support chain comprises a lower support insulating cylinder (2), and the motion chain comprises a connected insulating pull rod (1) and a conductive rod (11); the inner cavity of the lower support insulating cylinder (2) and the bellows (701) of the vacuum arc extinguishing chamber (7) are connected to form a normal pressure gas chamber; a high pressure gas chamber is formed between the support chain and the container; an outer shield (4) is arranged inside the high pressure gas chamber.

2. A locomotive circuit breaker according to claim 1, characterized in that: The outer shield (4) comprises a cylinder (41), wherein both ends of the cylinder (41) are open and one end has a flange (42).

3. A locomotive circuit breaker according to claim 2, characterized in that: The flange (42) is turned outward.

4. A locomotive circuit breaker according to claim 1 or 2, characterized in that: The distance between the outer shield (4) and the moving end conductive part (5) is 40% to 60% of the shortest distance between the moving end conductive part (5) and the housing cover plate (10).

5. A locomotive circuit breaker according to claim 1 or 2, characterized in that: The inner diameter of the outer shield (4) is 1.3-1.6 times the outer diameter of the lower supporting insulating cylinder (2).

6. A locomotive circuit breaker according to claim 1 or 2, characterized in that: The inner diameter of the outer shield (4) is 1.5 times the outer diameter of the lower supporting insulating cylinder (2).

7. A locomotive circuit breaker according to claim 1, characterized in that: The container comprises a shell (3) and a shell cover (10) which are fixedly connected.

8. A locomotive circuit breaker according to claim 1, characterized in that: When the switch is opened, the distance between the insulating pull rod insert (8) and the lower end surface of the outer shield (4) is greater than the distance between the lower end of the outer shield (4) and the lower end surface of the moving end conductive part (5).

9. A long-life tank locomotive high-voltage electrical equipment assembly, characterized in that: A locomotive circuit breaker comprising the circuit breaker according to any one of claims 1 to 8.

10. A locomotive, characterized in that: Including the tank locomotive high-voltage electrical assembly equipment as described in claim 9.

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