An environmentally friendly 12kV outdoor ring network power supply unit

Abstract

The present invention discloses an environmentally friendly 12kV outdoor ring network power supply unit, including an outer box, in which an inflatable compartment, a circuit breaker operating mechanism, and an isolating switch mechanism are arranged; the inflatable compartment is a sealed box body, and the box body is filled with environmentally friendly gas; the inflatable compartment is provided with a main bus, a branch bus, and three groups of disconnecting combination switches, wherein one group of disconnecting combination switches is arranged on the upper side of the inflatable compartment, and the other two groups of disconnecting combination switches are arranged on the lower side of the inflatable compartment, and the three groups of disconnecting combination switches have the same structure; the three groups of disconnecting combination switches are respectively connected to the cable bushing through the branch bus; the two ends of the main bus are connected to the main bus side expansion bushing; the disconnecting combination switch includes a sealed pole assembly, a three-position switch assembly, an isolating static contact, and a grounding static contact. The environmentally friendly 12kV outdoor ring network power supply unit of the present invention has the remarkable advantages of compact structure, small footprint, convenient maintenance, high reliability, environmental protection and energy saving.

Description

Technical Field

[0001] The invention belongs to the technical field of power switches, and in particular relates to an environmentally friendly 12kV outdoor ring network power supply unit. Background Art

[0002] The 12kV ring network power supply unit has a wide range of uses and important value in the power system. It has strong adaptability and can meet the power needs in different scenarios. In outdoor power distribution, the 12kV ring network power supply unit is suitable for ring network power supply or dual radiation power supply with 10kV~35kV power supply lines, and can also be used for terminal power supply. In the power supply site, the power supply unit can be used to achieve power control and protection.

[0003] The existing 12kV outdoor ring network power supply units are mainly divided into two types:

[0004] The first is a conventional product on the market, which is to assemble the traditional sulfur hexafluoride insulated 12kV power supply unit in a box transformer or outdoor box according to the primary wiring scheme to complete the reception and distribution of electric energy. Since sulfur hexafluoride is a greenhouse gas, the ring network power supply unit uses sulfur hexafluoride as an insulating and disconnecting gas, which has a serious impact on the environment.

[0005] The second type is a ring network power supply unit that uses clean air as the insulating medium. This type of power supply unit mostly uses a cable-forward and cable-out method. This method has the disadvantages of large cable usage, high manufacturing cost, large size, and large footprint. Summary of the invention

[0006] The present invention aims at the above problems, makes up for the deficiencies of the prior art, and provides an environmentally friendly 12kV outdoor ring network power supply unit, including an outer box, in which an inflatable compartment, a circuit breaker operating mechanism, and an isolating switch mechanism are arranged;

[0007] The inflatable compartment is a sealed box filled with environmentally friendly gas; a gas box shell is arranged outside the inflatable compartment, and the circuit breaker operating mechanism and the disconnector mechanism are arranged outside the inflatable compartment and fixed on the gas box shell; a main bus side expansion sleeve and two groups of cable sleeves are arranged on the side of the gas box shell, and a group of cable sleeves is arranged at the back of the gas box shell;

[0008] The inflatable compartment is provided with a main busbar, a branch busbar and three groups of disconnection combination switches; one of the three groups of disconnection combination switches is arranged on the upper side of the inflatable compartment, and the other two groups of disconnection combination switches are arranged on the lower side of the inflatable compartment, and the three groups of disconnection combination switches have the same structure; the three groups of disconnection combination switches are respectively connected to the cable bushings through the branch busbars; both ends of the main busbar are connected to the expansion bushings on the main busbar side;

[0009] The partition combined switch includes a solid-sealed pole column assembly, a three-position switch assembly, an isolating static contact, and a grounding static contact; the isolating static contact is fixed on the main bus, and the isolating static contact is electrically connected to the three-position switch assembly; the grounding static contact is fixed on the gas tank housing; the three-position switch assembly is connected to the disconnector operating mechanism;

[0010] The circuit breaker operating mechanism is connected to the solid-sealed pole column assembly.

[0011] Preferably, the three partition combined switches are respectively a first partition combined switch, a second partition combined switch, and a third partition combined switch; the third partition combined switch is horizontally arranged on the upper side of the gas-filled compartment, and the first partition combined switch and the second partition combined switch are vertically arranged on the lower side of the gas-filled compartment, and the first partition combined switch and the second partition combined switch are mirror-image arranged.

[0012] The above-mentioned third partition combined switch is horizontally arranged on the upper side of the gas-filled compartment, that is, the partition combined switch is horizontally arranged on the upper side of the gas-filled compartment; the above-mentioned first partition combined switch and the second partition combined switch are vertically arranged on the lower side of the gas-filled compartment, that is, the first partition combined switch and the second partition combined switch are vertically arranged on the lower side of the gas-filled compartment. This setting method is a "pin" shape design, which is different from the "left, middle, right" structure design.

[0013] Preferably, the solid-sealed pole column assembly includes a pole column body, the outside of the pole column body is integrally solid-sealed by epoxy resin, a vacuum interrupter is arranged on the upper side of the pole column body, and an operating pull rod is arranged at the lower part of the pole column body; static conductive rods and moving conductive rods are arranged at the upper and lower ends of the vacuum interrupter; a static end outlet seat is arranged at the top end of the pole column body, one end of the static end outlet seat is rotatably connected to the three-position switch assembly, and the other end of the static end outlet seat is electrically connected to the static conductive rod; a moving end outlet seat is fixedly arranged on one side of the pole column body, and the moving end outlet seat is connected to the moving conductive rod through a flexible connection; the tail end of the moving conductive rod is connected to the operating pull rod; an operating shaft is arranged at the tail end of the operating pull rod, and the operating shaft is connected to the circuit breaker operating mechanism.

[0014] The present invention utilizes that epoxy resin has a higher electric field strength than environmentally friendly gas. Through electric field optimization, the high electric field is located within the epoxy resin, thereby reducing the electric field strength in the environmentally friendly gas, and further achieving the purpose of replacing sulfur hexafluoride insulation with environmentally friendly air.

[0015] Preferably, the three-position switch assembly is a three-phase structure, and each phase of the three-position switch assembly includes two moving blades, a driving sheath, and two sets of clamping devices; the driving sheath is arranged on the outside of the two moving blades, and the two ends of the two moving blades are clamped by clamping devices; the lower ends of the two moving blades are installed on the static end outlet seat of the sealed pole, and the upper ends of the two moving blades are connected to the isolating static contact through the clamping device, and the driving sheath is connected to the isolating switch operating mechanism.

[0016] The driving sheath is arranged on the outside of the two moving blades and exposes the connection position between the moving blades and the static end outlet seat, the connection point between the moving blades and the clamping device, and the connection point between the moving blades and the isolating static contact, so that the moving blades are conductively connected to the clamping device, the static end outlet seat, and the isolating static contact.

[0017] The driving sheath in the present invention is a nylon driving sheath.

[0018] Preferably, the main busbar is in a U-shape with left and right sides extending horizontally, the main busbar is made of aluminum alloy, and the cross-section of the main busbar is a rectangle with rounded corners; the branch busbar is a round rod copper conductor formed by bending.

[0019] Preferably, the isolating static contact is formed by welding a conductor and a field control component, and the welding method is silver brazing. The conductor is formed by fixedly connecting a connecting part, a middle part, and a lower part. A threaded hole is arranged on the top surface of the connecting part, and the threaded hole is connected to the main busbar. The middle part is a rounded rectangular parallelepiped, and the two ends of the field control component are hemispheres, and the middle part is a cylinder. The diameters of the hemispheres and the cylinder are the same spherical surface. The field control component is provided with a groove, and the lower bottom end of the conductor is arranged in the groove.

[0020] The connecting part and the middle part of the conductor are an integrally formed structure. The silver soldering method makes the connection between the conductor and the field control unit firm and has good conductivity.

[0021] The isolating static contact plays a role in controlling the electric field strength and also plays a role in limiting the moving blade.

[0022] Preferably, a cable testing device is also provided in the outer box. The cable testing device is a three-phase structure. Each phase of the cable testing device includes a moving knife switch and a moving knife switch shaft. The moving knife switch shaft is in a grounded state. The cable testing device consists of two groups. The two groups of cable testing devices have the same structure, namely a first cable testing device and a second cable testing device, which are respectively arranged on the left and right sides of the lower part of the outer side of the inflatable compartment. When the moving knife switch is closed, the moving knife switch is connected to the lower end of the grounding static contact.

[0023] Preferably, the power supply unit is further provided with a pressure relief device which is arranged at the lower part of the gas-filled compartment, and a sealing ring and a fastener are arranged between the pressure relief device and the gas-filled compartment.

[0024] When the pressure in the gas-filled compartment rises abnormally, the pressure relief device can automatically release the pressure to ensure the safe operation of the power supply unit.

[0025] Preferably, the power supply unit further includes a density relay which is installed outside the gas-filled compartment, and a sealing ring is arranged between the density relay and the gas-filled compartment.

[0026] Preferably, the environmental protection gas is clean and dry air or nitrogen.

[0027] Advantages of the present invention:

[0028] (1) The present invention uses an environmental protection gas as the insulating medium. The branch busbar is made of a round bar copper conductor through bending processing, and the main busbar is a U-shaped aluminum alloy conductor horizontally extended on the left and right sides. The cross-section of the main busbar is a rectangle with rounded corners all around. While ensuring the current-carrying capacity, the main busbar can evenly distribute the electric field well and meet the requirements of environmental protection gas insulation. At the same time, the high electric field is set in the epoxy resin, reducing the electric field intensity in the environmental protection gas, thereby realizing the replacement of sulfur hexafluoride insulation with environmental protection air. The present invention avoids the generation of toxic and harmful gases under the action of an electric arc by sulfur hexafluoride gas, and avoids the influence of sulfur hexafluoride on the environment and on operation and maintenance, and overhaul personnel.

[0029] (2) The present invention optimizes the internal structure of the power supply unit. A group of disconnecting combined switches are arranged on the upper side of the gas-filled compartment, and the other two groups of disconnecting combined switches are arranged on the lower side of the gas-filled compartment. The primary main circuit adopts a "pin" shape design, optimizing the structure of the product and reducing the floor area of the power supply unit.

[0030] (3) The present invention is provided with two groups of cable bushings on the side of the gas tank housing and one group of cable bushings on the back of the gas tank housing; the ring network incoming cable is connected on the left and right sides of the power supply unit, and the outgoing cable is connected at the rear side of the power supply unit. This design optimizes the incoming and outgoing cable methods, reduces the length of the connecting cable, and thus saves the project cost.

[0031] (4) The present invention is also provided with two groups of knife-switch type cable test devices. This design realizes the cable withstand voltage test without disassembling the cable while meeting the grounding capacity. Therefore, the present invention has the advantages of convenient testing and convenient maintenance. Description of the drawings

[0032] Figure 1 is a general assembly schematic diagram of an environmental protection type 12 kV outdoor ring network power supply unit;

[0033] Figure 2 is a schematic diagram of the general assembly of the inflatable compartment;

[0034] Figure 3 It is a schematic diagram of the structure of the outer box;

[0035] Figure 4 It is a rear view of the structural layout inside the inflatable compartment;

[0036] Figure 5 It is a front view of the structural arrangement of the exterior of the inflatable compartment;

[0037] Figure 6 It is a three-dimensional diagram of the internal structure of the inflatable compartment;

[0038] Figure 7 It is a three-dimensional diagram of the partition combination switch;

[0039] Figure 8 It is a cross-sectional view of the partition combination switch;

[0040] Fig. 9 This is the diagram of the cable test device in the open state;

[0041] Fig.10 This is the diagram of the cable test device in the closed state;

[0042] Fig.11 It is a schematic diagram of the structure of the isolating static contact;

[0043] Fig.12 It is a schematic diagram of the structure of a three-position switch assembly;

[0044] Fig.13 It is a structural diagram of the main busbar assembly.

[0045] In the figure:

[0046] 1 is the outer box;

[0047] 2 is an inflatable compartment;

[0048] 2-1 is the first isolation combination switch;

[0049] 2-1-1 is the moving end outlet seat, 2-1-2 is the isolating static contact, 2-1-2-1 is the conductor, 2-1-2-2 is the field control, a is the connecting part, b is the middle part, c is the lower part, 2-1-3 is the grounding static contact, 2-1-4 is the operating shaft, 2-1-5 is epoxy resin, 2-1-6 is the operating pull rod, 2-1-7 is the soft connection, 2-1-8 is the vacuum interrupter, 2-1-9 is the static end outlet seat, and 2-1-10 is the installation base;

[0050] 2-2 is the second partition combination switch;

[0051] 2-3 is the third partition combination switch;

[0052] 2-4 are main busbar components;

[0053] 2-4-1 is the expansion bushing on the main busbar side, and 2-4-2 is the main busbar;

[0054] 2-5 is the first cable casing;

[0055] 2-6 is a second cable casing;

[0056] 2-7 is the third cable casing;

[0057] 2-8 is the air box shell;

[0058] 2-9 is the pole body;

[0059] 2-10 is a three-position switch assembly;

[0060] 2-10-1 is the moving blade, 2-10-2 is the clamping device, and 2-10-3 is the driving sheath;

[0061] 2-11-1 is the upper branch bus, 2-11-2 is the first lower branch bus, and 2-11-3 is the second lower branch bus;

[0062] 3-1 is the first circuit breaker operating mechanism;

[0063] 3-2 is the second circuit breaker operating mechanism;

[0064] 3-3 is the third circuit breaker operating mechanism;

[0065] 4-1 is the first isolating switch mechanism;

[0066] 4-2 is the second isolating switch mechanism;

[0067] 4-3 is the third isolating switch mechanism;

[0068] 5 is the density relay;

[0069] 6 is a pressure release device;

[0070] 7-1 is the moving knife switch;

[0071] 7-2 is the rotating shaft of the moving knife switch. DETAILED DESCRIPTION

[0072] In order to make the technical problems, technical solutions and beneficial effects solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific implementation methods. It should be understood that the specific implementation methods described herein are only used to explain the present invention and are not used to limit the present invention.

[0073] like Figures 1 to 13As shown, an environmentally friendly 12kV outdoor ring network power supply unit includes an outer box 1, in which an inflatable compartment 2, a circuit breaker operating mechanism, and an isolating switch mechanism are arranged; the inflatable compartment 2 is a sealed box body, and the box body is filled with environmentally friendly gas; a gas box shell 2-8 is arranged outside the inflatable compartment 2, and the circuit breaker operating mechanism and the isolating switch mechanism are arranged outside the inflatable compartment 2 and fixed on the gas box shell 2-8;

[0074] The side of the gas box housing 2-8 is provided with a main bus side expansion sleeve 2-4-1 and two groups of cable sleeves, and the back of the gas box housing 2-8 is provided with a group of cable sleeves;

[0075] A main busbar 2-4-2, a branch busbar and three groups of partition combination switches are arranged inside the inflatable compartment 2. The three groups of partition combination switches are respectively connected to the cable bushings through the branch busbars; the two groups of partition combination switches located at the lower side of the inflatable compartment 2 are respectively connected to the cable bushings located on the side of the gas box shell 2-8 through the branch busbars;

[0076] like Fig.13 As shown, both ends of the main busbar 2-4-2 are connected to the main busbar side expansion sleeve 2-4-1; the main busbar 2-4-2 and the main busbar side expansion sleeve 2-4-1 form a main busbar assembly 2-4;

[0077] like Figure 8 As shown, the isolating combination switch includes a sealed pole assembly, a three-position switch assembly 2-10, an isolating static contact 2-1-2, and a grounding static contact 2-1-3; the isolating static contact 2-1-2 is fixed on the main bus 2-4-2, and the isolating static contact 2-1-2 is conductively connected to the three-position switch assembly 2-10; the grounding static contact 2-1-3 is fixed on the gas box housing 2-8; the three-position switch assembly 2-10 is connected to the isolating switch operating mechanism;

[0078] The circuit breaker operating mechanism is connected to the sealed pole assembly, and the circuit breaker operating mechanism controls the opening and closing of the partition combination switch in the gas-filled compartment 2.

[0079] The inflatable compartment 2 of the present invention is filled with environmentally friendly gas, which is clean and dry air or nitrogen. The internal environment of the inflatable compartment 2 is completely separated from the external environment and is therefore not affected by external environmental conditions.

[0080] One end of the grounding static contact 2-1-3 is installed inside the air box housing 2-8, and the other end of the grounding static contact 2-1-3 is arranged outside the air box housing 2-8. When the three-position switch assembly 2-10 rotates to the position connected with the grounding static contact 2-1-3, a grounding loop is formed.

[0081] Specifically, Figure 6As shown, the three groups of partition combination switches are respectively the first partition combination switch 2-1, the second partition combination switch 2-2, and the third partition combination switch 2-3; the third partition combination switch 2-3 is horizontally arranged on the upper side inside the inflatable compartment 2, the first partition combination switch 2-1 and the second partition combination switch 2-2 are vertically arranged on the lower side inside the inflatable compartment 2, and the first partition combination switch 2-1 and the second partition combination switch 2-2 are mirror-arranged.

[0082] like Figure 4 As shown, the busbars in the present invention include a main busbar 2-4-2 and a branch busbar, and the branch busbars include an upper branch busbar 2-11-1, a first lower branch busbar 2-11-2, and a second lower branch busbar 2-11-3; the branch busbar connected to the first partition combination switch 2-1 is the first lower branch busbar 2-11-2, the branch busbar connected to the second partition combination switch 2-2 is the second lower branch busbar 2-11-3, and the branch busbar connected to the third partition combination switch 2-3 is the upper branch busbar 2-11-1. The branch busbar is a round copper conductor that is bent and processed, and the branch busbar evens out the electric field around the conductor.

[0083] like Figure 4 As shown, the first partition combination switch 2-1 is located at the lower left side of the gas-filled compartment 2, and the moving end outlet seat 2-1-1 of the first partition combination switch 2-1 is conductively connected to the first cable bushing 2-5 through the first lower branch bus 2-11-2. The first cable bushing 2-5 and the second cable bushing 2-6 are the ring network cable inlet bushings, and are respectively connected to the ring network inlet cables when the equipment is running.

[0084] The second disconnecting combination switch 2-2 is located at the lower right side of the gas-filled compartment 2, and its moving end outlet seat 2-1-1 is conductively connected to the second cable bushing 2-6 through the second lower branch bus 2-11-3. The third disconnecting combination switch 2-3 is located at the upper middle position of the gas-filled compartment 2, and its moving end outlet seat 2-1-1 is conductively connected to the third cable bushing 2-7 through the upper branch bus 2-11-1. When the equipment is running, the third cable bushing 2-7 is connected to the load-end cable.

[0085] Specifically, Figure 8As shown, the sealed pole assembly includes a pole body 2-9, the exterior of the pole body 2-9 is integrally sealed by epoxy resin 2-1-5, and a vacuum arc extinguishing chamber 2-1-8 is arranged on the upper side of the pole body 2-9; a static conductive rod and a dynamic conductive rod are arranged at the upper and lower ends of the vacuum arc extinguishing chamber 2-1-8; a static end outlet seat 2-1-9 is arranged at the top of the pole body 2-9, one end of the static end outlet seat 2-1-9 is rotatably connected to the three-position switch assembly 2-10, and the other end of the static end outlet seat 2-1-9 is conductively connected to the static conductive rod; a dynamic end outlet seat 2-1-1 is fixedly arranged on one side of the pole body 2-9, and the dynamic end outlet seat 2-1-1 is connected to the dynamic conductive rod through a flexible connection 2-1-7; an operating pull rod 2-1-6 is arranged at the tail end of the dynamic conductive rod; an operating shaft 2-1-4 is arranged at the tail end of the operating pull rod 2-1-6.

[0086] like Figure 7 As shown, the isolating combination switch is a three-phase structure, and the structure of each phase is the same. The three-phase structure shares a mounting base 2-1-10 and a same operating shaft 2-1-4.

[0087] like Figure 8 As shown, a part of the moving end outlet seat 2-1-1, the vacuum arc extinguishing chamber 2-1-8, and a part of the static end outlet seat 2-1-9 are sealed inside the epoxy resin 2-1-5 to form the pole body 2-9, and the operating pull rod 2-1-6 is connected to the vacuum arc extinguishing chamber 2-1-8 through the moving conductive rod.

[0088] When the operating shaft 2-1-4 rotates, the operating rod 2-1-6 moves up and down, pulling the vacuum interrupter 2-1-8 to open and close, thus realizing the on and off of the circuit. The pole body 2-9 is made of epoxy resin 2-1-5, which utilizes the fact that epoxy resin 2-1-5 has a higher electric field strength than environmentally friendly gas. Through electric field optimization, the high electric field is located in the epoxy resin 2-1-5, which reduces the strength of the electric field in the environmentally friendly gas, thereby realizing environmentally friendly air replacing sulfur hexafluoride insulation.

[0089] Specifically, the three-position switch assembly 2-10 is a three-phase structure, and each phase of the three-position switch assembly 2-10 includes two moving blades 2-10-1, a driving sheath 2-10-3, and two sets of clamping devices 2-10-2; the driving sheath 2-10-3 is sleeved on the outside of the moving blade 2-10-1, and the two sides of the moving blade 2-10-1 are clamped by the clamping device 2-10-2, the lower end of the moving blade 2-10-1 is installed on the static end outlet seat 2-1-9, and the upper end of the moving blade 2-10-1 is connected to the isolating static contact 2-1-2 through the clamping device 2-10-2, and the driving sheath 2-10-3 is connected to the isolating switch operating mechanism.

[0090] The driving sheath 2-10-3 is also a three-phase structure. The driving sheath 2-10-3 is always connected to the isolating switch operating mechanism through the sealing shaft, that is, the isolating switch operating mechanism drives the driving sheath to rotate, and the driving sheath drives the moving blade to rotate, thereby realizing the closing, opening and grounding of the three-position switch assembly 2-10.

[0091] The drive sheath 2-10-3 is preferably a nylon drive sheath.

[0092] In the present invention, a part of the operating shaft 2-1-4 is arranged inside the gas box housing 2-8, and the other part is arranged outside the gas box housing 2-8 and connected to the circuit breaker operating mechanism. The circuit breaker operating mechanism controls the opening and closing of the sealed pole assembly. Figure 5 As shown, correspondingly, the operating shaft 2-1-4 in the first disconnect combination switch 2-1 is connected to the first circuit breaker operating mechanism 3-1, the operating shaft 2-1-4 in the second disconnect combination switch 2-2 is connected to the second circuit breaker operating mechanism 3-2, and the operating shaft 2-1-4 in the third disconnect combination switch 2-3 is connected to the third circuit breaker operating mechanism 3-3.

[0093] Specifically, Fig.11 As shown, the isolating static contact 2-1-2 is welded by the conductor 2-1-2-1 and the field control 2-1-2-2 by silver brazing. The conductor 2-1-2-1 is fixedly connected by the connecting part a, the middle part b, and the lower part c. Two threaded holes are arranged on the top surface of the connecting part a, and the threaded holes are connected to the main bus 2-4-2. The middle part b is a rounded rectangular parallelepiped. The two ends of the field control 2-1-2-2 are hemispheres, and the middle part is a cylinder. The diameters of the hemispheres and the cylinder are the same as the spherical surface. The field control 2-1-2-2 is provided with a groove, and the lower bottom end of the conductor 2-1-2-1 is arranged in the groove.

[0094] The conductor 2-1-2-1 is a T-shaped structure formed by the connection part a, the middle part b, and the lower part c. The connection part a is 22mm thick, and the distance between the centers of the two threaded holes is 30mm. The two threaded holes are used to connect the main bus 2-4-2. The groove of the field control 2-1-2-2 is 8mm wide and 10mm long. The isolating static contact 2-1-2 plays a role in uniform electric field and also plays a role in limiting the closing position of the moving blade 2-10-1.

[0095] Specifically, a cable test device is also provided in the outer box 1. The cable test device is a knife switch structure, including a moving knife switch 7-1 and a moving knife switch shaft 7-2. There are two groups of cable test devices, and the two groups have the same structure, namely a first cable test device and a second cable test device, which are respectively provided on the left and right sides of the lower outer side of the inflatable compartment 2. The cable test device in the present invention is used in conjunction with the power frequency withstand voltage equipment to test and verify the performance of the cable to ensure that the cable can operate safely and reliably under normal working conditions.

[0096] A first cable test device is installed on the left side of the lower outer part of the inflatable compartment 2, and a second cable test device is installed on the right side of the lower outer part of the inflatable compartment 2. Fig. 9 and Fig.10 As shown, the cable test device is a three-phase structure, each phase is composed of a moving knife switch 7-1 and a moving knife switch shaft 7-2, and the moving knife switch 7-1 is preferably a short-circuit moving knife switch.

[0097] The short-circuit moving knife switch is formed by bending two copper plates with a thickness of 4 mm and a width of 30 mm. The short-circuit moving knife switch is rotatably fixed on the moving knife switch shaft 7-2, and the distance between the two copper plates is 17 mm. The moving knife switch shaft 7-2 is always in a grounded state.

[0098] When the first cable test device is closed, the moving knife switch 7-1 is connected to the lower part of the grounding static contact 2-1-3, meeting the dynamic thermal stability requirements of the grounding circuit. Operate the three-position switch assembly 2-10 of the first disconnector combination switch 2-1 to ground and close, and the circuit breaker operating mechanism to close. At this time, the ring network incoming cable is reliably grounded through the first cable bushing 2-5, the first lower branch bus 2-11-2, the first disconnector combination switch 2-1, and the first cable test device. Fig. 9 As shown, when only the first cable test device is separated, the power frequency withstand voltage test can be carried out on the ring network incoming cable installed on the first cable sheath 2-5 through the lower part of the grounding static contact 2-1-3 using the power frequency withstand voltage equipment, thereby realizing the cable withstand voltage test without disassembling the cable.

[0099] Specifically, the power supply unit is also provided with a pressure release device 6, which is arranged at the lower part of the inflatable compartment 2. A sealing ring and fasteners are arranged between the pressure release device 6 and the inflatable compartment. When the pressure in the inflatable compartment 2 rises abnormally, the pressure release device 6 can automatically release the pressure to ensure the safe operation of the equipment.

[0100] The environmentally friendly 12kV outdoor ring network power supply unit of the present invention is also provided with a density relay 5 , which is installed on the upper front part of the air-filled compartment 2 , and a sealing ring is provided between the density relay 5 and the air-filled compartment 2 .

[0101] like Figure 5As shown, the first isolating switch mechanism 4-1 is installed on the outside front of the inflatable compartment 2. The first isolating switch mechanism 4-1 is connected to the driving sheath 2-10-3 of the first partition combination switch 2-1 inside the inflatable compartment 2 to operate the closing, opening and grounding of the three-position switch assembly 2-10. The second isolating switch mechanism 4-2 is installed on the outside front of the inflatable compartment 2, and the third isolating switch mechanism 4-3 is installed on the outside front of the inflatable compartment 2. The second isolating switch mechanism 4-2 and the third isolating switch mechanism 4-3 correspond to the second partition combination switch 2-2 and the third partition combination switch 2-3 inside the inflatable compartment 2, respectively, and their connection method and working principle are the same as the first partition combination switch 2-1.

[0102] The main busbar assembly 2-4 of the present invention is a three-phase structure, each phase is composed of two main busbar side expansion sleeves 2-4-1 and a main busbar 2-4-2, one end of the main busbar side expansion sleeve 2-4-1 is located inside the inflation compartment 2, and the other end is located outside the air box shell 2-8.

[0103] The outer box 1 of the present invention is composed of painted carbon steel plates and has high strength and protection level (IP54). The interior of the outer box 1 is divided into multiple functional areas, including an operating room, a mechanism room, a pressure relief channel, a cable connection compartment, and a cable test device room. The setting of these functional areas makes the operation of the equipment safer, more reliable and more efficient. The overlapping surfaces between the plates of the outer box 1 are sandwiched with a silicone rubber pad with a thickness of 1 mm and a width of 10 mm, achieving the protection level IP54 requirements.

[0104] The operation room is located in front of the outer box 1. The front door can be opened to manually operate the partition combination switch on the spot. The mechanism compartment is located at the rear of the operation room, where the various circuit breaker operating mechanisms and disconnector mechanisms are located. The first cable compartment is located at the lower left part of the outer box 1, where the ring network incoming cable is installed. The compartment opening is subject to mechanical interlocking and logic restrictions. When the arc is burning, the high-pressure gas is discharged downward into the cable trench through the pressure relief channel. The second cable compartment is located at the lower right part of the outer box 1, where the ring network incoming cable is installed. The downward discharge of high-pressure gas well ensures the safety of the surrounding operation and maintenance personnel and equipment. The first cable test device compartment is located in the middle of the left side of the outer box 1, above the first cable compartment, and the compartment opening and cable withstand voltage test are subject to mechanical interlocking and logic restrictions. The second cable test device compartment is located in the middle of the right side of the outer box 1, above the second cable compartment, and the compartment opening and cable withstand voltage test are subject to mechanical interlocking and logic restrictions. The independent cable test compartment ensures the safety of the operation and maintenance personnel when conducting the cable withstand voltage test. The third cable compartment is an outgoing cable compartment, which is located in the middle of the rear of the outer box 1, and is convenient for connecting to the load equipment transformer through cables.

[0105] It can be understood that the above specific description of the present invention is only used to illustrate the present invention and is not limited to the technical solutions described in the embodiments of the present invention. Those skilled in the art should understand that the present invention can still be modified or replaced by equivalents to achieve the same technical effects; as long as the use requirements are met, they are within the protection scope of the present invention.

Claims

1. An environmentally friendly 12kV outdoor ring network power supply unit, characterized in that: It comprises an outer box, in which a gas-filled compartment, a circuit breaker operating mechanism and an isolating switch mechanism are arranged; The inflatable compartment is a sealed box filled with environmentally friendly gas; a gas box shell is arranged outside the inflatable compartment, and the circuit breaker operating mechanism and the disconnector mechanism are arranged outside the inflatable compartment and fixed on the gas box shell; a main bus side expansion sleeve and two groups of cable sleeves are arranged on the side of the gas box shell, and a group of cable sleeves is arranged at the back of the gas box shell; The inflatable compartment is provided with a main busbar, a branch busbar and three groups of disconnection combination switches; one of the three groups of disconnection combination switches is arranged on the upper side of the inflatable compartment, and the other two groups of disconnection combination switches are arranged on the lower side of the inflatable compartment, and the three groups of disconnection combination switches have the same structure; the three groups of disconnection combination switches are respectively connected to the cable bushings through the branch busbars; both ends of the main busbar are connected to the expansion bushings on the main busbar side; The isolating combination switch comprises a sealed pole assembly, a three-position switch assembly, an isolating static contact, and a grounding static contact; the isolating static contact is fixed on the main busbar, and the isolating static contact is conductively connected to the three-position switch assembly; the grounding static contact is fixed on the gas box housing; the three-position switch assembly is connected to the isolating switch operating mechanism; The circuit breaker operating mechanism is connected to the sealed pole assembly; The sealed pole assembly comprises a pole body, the exterior of which is integrally sealed by epoxy resin, a vacuum arc extinguishing chamber is arranged on the upper side of the pole body, and an operating pull rod is arranged on the lower part of the pole body; a static conductive rod and a dynamic conductive rod are arranged at the upper and lower ends of the vacuum arc extinguishing chamber; a static end outlet seat is arranged at the top of the pole body, one end of the static end outlet seat is rotatably connected to the three-position switch assembly, and the other end of the static end outlet seat is conductively connected to the static conductive rod; a dynamic end outlet seat is fixedly arranged on one side of the pole body, and the dynamic end outlet seat is connected to the dynamic conductive rod through a soft connection; the tail end of the dynamic conductive rod is connected to the operating pull rod; an operating shaft is arranged at the tail end of the operating pull rod, and the operating shaft is connected to the circuit breaker operating mechanism; The isolating static contact is welded by a conductor and a field control unit, and the welding method is silver brazing. The conductor is fixedly connected by a connecting part, a middle part, and a lower part. A threaded hole is arranged on the top surface of the connecting part, and the threaded hole is connected to the main busbar. The middle part is a rounded rectangular parallelepiped. The two ends of the field control unit are hemispheres, and the middle part is a cylinder. The diameters of the hemisphere and the cylinder are the same as those of the spherical surface. The field control unit is provided with a groove, and the lower bottom end of the conductor is arranged in the groove.

2. The environmentally friendly 12kV outdoor ring network power supply unit according to claim 1 is characterized in that: The three groups of partition combination switches are respectively the first partition combination switch, the second partition combination switch and the third partition combination switch; the third partition combination switch is horizontally arranged on the upper side of the inflatable compartment, the first partition combination switch and the second partition combination switch are vertically arranged on the lower side of the inflatable compartment, and the first partition combination switch and the second partition combination switch are mirror-arranged.

3. The environmentally friendly 12kV outdoor ring network power supply unit according to claim 1 is characterized in that: The three-position switch assembly is a three-phase structure, and each phase of the three-position switch assembly includes two moving blades, a driving sheath, and two sets of clamping devices; the driving sheath is arranged on the outside of the two moving blades, and the two ends of the two moving blades are clamped by clamping devices; the lower ends of the two moving blades are installed on the static end outlet seat of the sealed pole, and the upper ends of the two moving blades are connected to the isolating static contact through the clamping device, and the driving sheath is connected to the isolating switch operating mechanism.

4. The environmentally friendly 12kV outdoor ring network power supply unit according to claim 1 is characterized in that: The main busbar is in the shape of a U-shape with left and right sides extending horizontally. The main busbar is made of aluminum alloy, and the cross-section of the main busbar is a rectangle with rounded corners. The branch busbar is made of round copper conductors through bending.

5. The environmentally friendly 12kV outdoor ring network power supply unit according to claim 1 is characterized in that: A cable testing device is also provided in the outer box. The cable testing device is a three-phase structure. Each phase of the cable testing device includes a moving knife switch and a moving knife switch shaft. The moving knife switch shaft is in a grounded state. The cable testing device consists of two groups. The two groups of cable testing devices have the same structure, namely a first cable testing device and a second cable testing device, which are respectively arranged on the left and right sides of the lower part of the outer side of the inflatable compartment. When the moving knife switch is closed, the moving knife switch is connected to the lower end of the grounding static contact.

6. The environmentally friendly 12kV outdoor ring network power supply unit according to claim 1, characterized in that: The power supply unit is also provided with a pressure release device, which is arranged at the lower part of the inflatable compartment. A sealing ring and a fastener are arranged between the pressure release device and the inflatable compartment.

7. The environmentally friendly 12kV outdoor ring network power supply unit according to claim 1 is characterized in that: The power supply unit further comprises a density relay, which is installed outside the gas-filled compartment, and a sealing ring is arranged between the density relay and the gas-filled compartment.

8. The environmentally friendly 12kV outdoor ring network power supply unit according to claim 1, characterized in that: The environmentally friendly gas is clean and dry air or nitrogen.

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