Composite combined electric appliance suitable for extremely low temperature environment

Abstract

The invention relates to the technical field of circuit emergency protection devices, in particular to a combined type combined electric appliance suitable for an extremely low temperature environment. The combined type combined electric appliance suitable for the extremely low temperature environment comprises a tank type circuit breaker, a current transformer and an isolation switch, the tank type circuit breaker comprises a circuit breaker tank body, one end of the current transformer is connected to the circuit breaker tank body, the other end of the current transformer is connected with a transition cylinder body, and the transition cylinder body is connected with the isolation switch. The disconnecting switch is connected with the other end of the transition cylinder, a heating gas chamber communicated with the interior of the circuit breaker tank is formed in the transition cylinder, and a cylinder heater is arranged on the transition cylinder. According to the combined type combined electric appliance suitable for the extremely low temperature environment, the heating area is increased on the basis of original heating outside a circuit breaker tank body, and the heating efficiency is improved.

Description

Technical Field

[0001] The invention relates to the technical field of circuit emergency protection devices, and in particular to a composite combined electrical appliance suitable for extremely low temperature environments. Background Art

[0002] The composite switchgear is a high-voltage switchgear that combines an open air-insulated switchgear with a gas-insulated metal-enclosed switchgear. The composite switchgear adopts a three-phase split-box structure, and the components are highly integrated and miniaturized, making the equipment compact. Compared with conventional open air-insulated switchgear, it saves 60% of the floor space, greatly saving installation land. The composite switchgear has a similar structure to the gas-insulated metal-enclosed switchgear, and both use SF6 as the breaking and insulating medium.

[0003] SF6 gas is a colorless, odorless, non-flammable gas with excellent electrical properties and chemical stability. Its insulation strength is much higher than that of air, which can effectively improve the insulation level of electrical equipment. At the same time, SF6 gas also has good arc extinguishing performance, which can quickly extinguish arcs when arcs occur, protecting the safe operation of electrical equipment. However, SF6 gas will liquefy in an environment below -60℃. As SF6 gas liquefies, the gas pressure in the equipment will decrease. When the gas pressure drops to the alarm or lockout threshold of the equipment, it will trigger the alarm or lockout mechanism of the equipment, causing the equipment to fail to work properly.

[0004] In the prior art, two solutions are usually adopted for the extremely low temperature working condition of -60℃. The first is to reduce the concentration of SF6 gas and use mixed gas as the breaking and insulating medium. Too low concentration of SF6 gas will affect the breaking effect and insulation capacity, and impure SF6 is a toxic gas. The second is to install a heating device in the casing of the composite combination electrical appliance to ensure that the temperature of SF6 gas is not lower than its liquefaction temperature.

[0005] The Chinese utility model patent with the authorization announcement number CN208352188U and the authorization announcement date 2019.01.08 discloses a tank circuit breaker cylinder assembly and an electric heating sleeve for a tank circuit breaker. The electric heating sleeve for a tank circuit breaker of the patent includes an open sleeve composed of at least two arc-shaped plates connected in opposite directions. The electric heating sleeve fixed sleeve is arranged on the outside of the tank body of the tank circuit breaker, and the gas chamber is heated through the tank body of the tank circuit breaker by the electric heating sleeve. The electric heating sleeve for a tank circuit breaker of the patent is only arranged on the outside of the tank body of the circuit breaker, and the gas chamber is heated through the tank body of the tank circuit breaker, which affects the heat transfer efficiency; and only part of the tank body of the circuit breaker is heated, and the heating range is limited. The mutual inductor and other components connected to the upper part of the tank body of the circuit breaker also have SF6 connected to the tank body of the circuit breaker. The gas there cannot be effectively heated, which also affects the heating efficiency of the gas to a certain extent; in addition, the outer side of the electric heating sleeve contacts the external environment, and the heat is easily lost, and the heating effect is not good. Summary of the invention

[0006] The purpose of the present invention is to provide a composite combined electrical appliance suitable for extremely low temperature environments, so as to solve the problem that the existing electric heating sleeve has insufficient coverage and affects the heating efficiency.

[0007] In order to solve the above problems, the composite combination electrical appliance suitable for extremely low temperature environment of the present invention adopts the following technical solutions: A composite combined electrical appliance suitable for extremely low temperature environments includes a tank-type circuit breaker, a current transformer and an isolating switch. The tank-type circuit breaker includes a circuit breaker tank body, one end of the current transformer is connected to the circuit breaker tank body, the other end of the current transformer is connected to a transition cylinder, the isolating switch is connected to the other end of the transition cylinder, a heating air chamber connected to the inside of the circuit breaker tank body is formed in the transition cylinder, and a cylinder heater is arranged on the transition cylinder.

[0008] Furthermore, the barrel heater is an electric heating sleeve arranged outside the transition barrel.

[0009] Furthermore, an in-tank electric heating rod is arranged in the circuit breaker tank body, and an electrode of the in-tank electric heating rod passes through the circuit breaker tank body and is insulated and sealed with the circuit breaker tank body.

[0010] Furthermore, an insulator is provided on the outside of the circuit breaker tank body at the position where the electrode of the electric heating rod in the tank passes through, and the insulator includes a sealing disk that is in contact with the outer wall of the circuit breaker tank body, and a sealing ring is provided between the sealing disk and the circuit breaker tank body, and the electrode and the circuit breaker tank body are insulated and sealed by the insulator and the sealing ring.

[0011] Furthermore, a groove adapted to the in-tank electric heating rod is provided on the inner side of the bottom of the circuit breaker tank body, and the in-tank electric heating rod is arranged in the groove.

[0012] Furthermore, a thickened portion with thickened wall thickness is provided at the bottom of the circuit breaker tank, and the groove is opened on the thickened portion.

[0013] Furthermore, an electric heating sleeve is installed outside the circuit breaker tank.

[0014] Furthermore, a tank heat insulation cover is provided outside the circuit breaker tank.

[0015] Furthermore, a cylinder heat insulation cover is provided on the outside of the transition cylinder.

[0016] Furthermore, the cylinder heat insulation cover and the tank heat insulation cover are connected to each other as a whole.

[0017] Beneficial effects: The composite combined electrical appliance suitable for extremely low temperature environments of the present invention is an improved invention. Through this solution, a transition cylinder is added between the current transformer and the disconnector, and a heating device is arranged on the transition cylinder, thereby increasing the heating area. The composite combined electrical appliance suitable for extremely low temperature environments of the present invention increases the heating area on the basis of the original heating outside the circuit breaker tank, thereby improving the heating efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of an embodiment of the composite combination electrical appliance applicable to an extremely low temperature environment of the present invention; Figure 2 for Figure 1 Middle AA section view; Figure 3 for Figure 1 A partial enlarged view of the connection between the electric heating rod in the middle tank and the circuit breaker tank body; Figure 4 The figure is a schematic diagram of the application state of an embodiment of the composite combination electrical appliance suitable for extremely low temperature environment of the present invention.

[0019] In the figure: 1. tank type circuit breaker; 2. current transformer; 3. disconnector; 4. circuit breaker tank; 5. transition cylinder; 6. heating gas chamber; 7. transition cylinder electric heating sleeve; 8. electric heating rod in the tank; 9. electrode; 10. insulator; 11. bolt fastener; 12. sealing disk; 13. sealing ring; 14. insulating end cap; 15. groove; 16. circuit breaker electric heating sleeve; 17. tank insulation cover; 18. cylinder insulation cover. DETAILED DESCRIPTION

[0020] The features and performance of the present invention are further described in detail below in conjunction with the embodiments.

[0021] The composite combined electrical appliance suitable for extremely low temperature environments of the present invention increases the heating area and improves the heating efficiency by arranging a transition cylinder at a position where a heating device cannot be originally arranged.

[0022] As a basic solution, the composite combination electrical appliance of the present invention is suitable for extremely low temperature environments. Figure 4 As shown, it includes a tank circuit breaker 1, a current transformer 2 and a disconnector 3. The main body of the tank circuit breaker 1 is a circuit breaker tank body 4. The current transformer 2 is arranged above the circuit breaker tank body 4 and is connected to the inside of the circuit breaker tank body 4. The disconnector 3 is arranged above the current transformer 2. There is a conductor inside the circuit breaker tank body 4 to connect the internal currents of the tank circuit breaker 1, the current transformer 2 and the disconnector 3. One end of the current transformer 2 is connected to the circuit breaker tank body 4, and the other end of the current transformer 2 is connected to a transition cylinder 5. The transition cylinder 5 is covered outside the conductor at the connection between the current transformer 2 and the disconnector 3, and the two ends are sealed and connected to the ends of the current transformer 2 and the disconnector 3, respectively, as shown in FIG. Figure 1 As shown, a heating air chamber 6 connected to the inside of the circuit breaker tank 4 is formed in the transition cylinder 5, and a cylinder heater is arranged on the transition cylinder 5 to heat the gas in the heating air chamber 6, thereby further improving the heating efficiency.

[0023] As a preferred embodiment, the barrel heater is a transition barrel electric heating sleeve 7 provided outside the transition barrel 5. The transition barrel electric heating sleeve 7 is a sleeve-shaped transition barrel electric heating sleeve 7, which is sleeved outside the transition barrel 5 and fits the outer wall of the transition barrel 5. The sleeve-shaped transition barrel electric heating sleeve 7 is easy to fix. In other optional embodiments, the barrel heater can use an electric heating rod to directly heat the SF6 gas inside the heating chamber 6, but the internal space of the transition barrel 5 is small, and the electric heating rod that is set too small may not achieve the target heating effect, and the electric heating rod that is set too large may affect the content of SF6 and thus affect the use effect of the composite combination electrical appliance.

[0024] As a preferred embodiment, an in-tank electric heating rod 8 is provided in the circuit breaker tank 4. The in-tank electric heating rod 8 is directly provided inside the gas chamber of the circuit breaker tank 4 to directly heat the SF6 gas, further improving the heating efficiency, ensuring that the SF6 gas is always in a gaseous state, and maintaining the insulation and arc extinguishing performance of the composite combination electrical appliance. The electrode of the in-tank electric heating rod 8 passes through the circuit breaker tank 4 and is insulated and sealed with the circuit breaker tank 4. The insulation seal ensures that the heating rod will not be in electrical contact with the outer wall of the circuit breaker tank 4 during operation, preventing the occurrence of electrical short circuit or leakage.

[0025] As a preferred embodiment, an insulator 10 is provided on the outer side of the circuit breaker tank body 4 at the position where the electrode 9 of the electric heating rod 8 in the tank passes through. Figure 3As shown, the insulator 10 is wrapped at the position where the electrode 9 passes through by casting, and the insulator 10 is fixed to the outer wall of the circuit breaker tank body 4 by bolt fasteners 11. The insulator 10 supports and fixes the electric heating rod 8 in the tank to prevent the electric heating rod 8 in the tank from shaking or falling off during operation. In other optional embodiments, the electric heating rod 8 in the tank is directly placed in the air chamber in the circuit breaker tank, and a fixing device can also be used to fix the electric heating rod 8 in the tank in the air chamber in the circuit breaker tank. The electric heating rod 8 in the tank and the fixing device will occupy a certain volume of the air chamber in the circuit breaker tank, resulting in a decrease in the SF6 gas content, which affects the use effect of the electrical equipment. The electric heating rod 8 in the tank is insulated and isolated from the circuit breaker tank body 4 by the insulator 10 on the outer wall of the circuit breaker tank body 4. The insulator 10 includes a sealing disk 12 that fits the outer wall of the circuit breaker tank body 4. A sealing ring 13 is arranged between the sealing disk 12 and the circuit breaker tank body 4 to enhance the sealing of the connection. The electrode 9 and the circuit breaker tank body 4 are insulated and sealed by the insulator 10 and the sealing ring 13, and the sealing ring 13 is arranged between the insulator 10 and the outer wall of the circuit breaker tank body 4, which plays a role in enhancing the sealing. This design not only ensures the stable connection between the insulator 10 and the circuit breaker tank body 4, but also prevents the interference of the external environment, such as moisture, dust, etc., from causing damage to the inside of the electrical appliance. An insulating end cap 14 is arranged on the insulator 10, and a hole is arranged on the insulating end cap 14 to connect the external power supply through the power wiring arranged at both ends of the electric heating rod 8 in the tank.

[0026] As a preferred embodiment, the inner side of the bottom of the circuit breaker tank body 4 is provided with a groove 15 adapted to the electric heating rod 8 in the tank. Figure 2 As shown, the in-tank electric heating rod 8 is arranged in the groove 15. The groove 15 is arranged on the inner side of the bottom of the circuit breaker tank body 4, which has the least impact on the original use effect of the electrical equipment and will not reduce the insulation distance of the circuit breaker arc extinguishing chamber to the ground. This design allows the in-tank electric heating rod 8 to fit more closely to the air chamber in the circuit breaker tank, improves the heating efficiency, and ensures the stability and safety of the in-tank electric heating rod 8 during operation.

[0027] As a preferred embodiment, the bottom of the circuit breaker tank body 4 is provided with a thickened portion with thickened wall thickness, and the thickened portion extends along the length direction of the bottom of the circuit breaker tank body 4, and the groove 15 is provided on the thickened portion, which does not affect the volume of the original internal air chamber of the circuit breaker tank body 4 and the content of SF6 gas in the air chamber, and minimizes the effect of adding a heating device on the use effect of the composite combination electrical appliance. In other optional embodiments, the in-tank electric heating rod 8 can also be directly arranged at the bottom of the circuit breaker tank body 4, and the SF6 gas in the air chamber can also be directly heated, but this method has a certain degree of influence on the content of SF6 gas in the air chamber.

[0028] As a preferred embodiment, a circuit breaker electric heating sleeve 16 is installed outside the circuit breaker tank body 4. The circuit breaker electric heating sleeve is adapted to the outer shape of the circuit breaker tank body 4 with thickened wall thickness, and the SF6 gas is prevented from liquefying in an extremely low temperature environment through the combined heating effect of the circuit breaker electric heating sleeve and the electric heating rod in the tank, thereby ensuring the insulation and arc extinguishing performance of the electrical appliance, improving the safety of the electrical appliance, and enabling the electrical appliance to operate normally in an extremely low temperature environment.

[0029] As a preferred embodiment, the outside of the circuit breaker tank body 4 and the outside of the transition cylinder body 5 are respectively provided with a tank body insulation cover 17 and a cylinder body insulation cover 18. The insulation cover is provided mainly to prevent the external strong wind from causing adverse effects on the tank type circuit breaker 1, such as reducing the heat dissipation efficiency, increasing the risk of operating failures, etc. At the same time, the stability and reliability of the equipment are improved. In some optional embodiments, the material of the insulation cover can be selected from metal, plastic or composite materials. The insulation cover made of metal has better protective performance and has certain strength and rigidity, but may not be conducive to heat preservation and has higher cost; the insulation cover made of plastic has lower cost and is easy to process and manufacture, but has poor durability and is easily damaged in extremely low temperature environments; the insulation cover made of composite materials combines the advantages of metal and plastic, and has better protective performance and durability.

[0030] As a preferred embodiment, the tank body insulation cover 17 and the cylinder body insulation cover 18 are connected to each other as a whole. The cylinder body insulation cover 18 and the tank body insulation cover 17, which are designed as a whole, form a large closed cover to wrap the circuit breaker tank body 4 and the transition cylinder body 5, reducing the heat loss of the heat released by the electric heating rod 8 in the tank, the transition cylinder body electric heating sleeve 7 outside the transition cylinder body 5, and the circuit breaker tank body electric heating sleeve 16 outside the circuit breaker tank body 4 in a low temperature environment, reducing the energy consumption of the heating system, improving the energy utilization efficiency, and effectively preventing the performance degradation of the composite combination switch due to heat loss in an extremely low temperature environment, ensuring that the composite combination switch can still work stably in a low temperature environment.

[0031] The specific implementation process of this embodiment is as follows: a transition cylinder 5 is placed at one end of the current sensor, both ends of the transition cylinder 5 are sealed and fixed, a transition cylinder electric heating sleeve 7 is installed outside the transition cylinder 5 and fixed with fasteners, and a corresponding power supply is connected; then the circuit breaker electric heating sleeve 16 is installed and fixed outside the circuit breaker tank 4 and a corresponding power supply is connected; the electric heating rod 8 in the tank is placed in the groove 15 of the gas chamber in the tank, and then both ends of the electric heating rod 8 in the tank are passed through and fixed to the outer wall of the circuit breaker tank 4, and part of the cast insulator 10 is passed through both ends of the electric heating rod 8 in the tank and the insulator 10 is fixed to the outer wall of the circuit breaker tank 4 with fasteners, and then the power wiring at both ends of the electric heating rod 8 in the tank is connected to the external power supply through the holes on the insulating end cap 14 to connect the corresponding power wiring, and finally the heat preservation cover is placed on the outside of the circuit breaker and the transition cylinder 5 and fixed with fasteners.

[0032] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. The patent protection scope of the present invention shall be based on the claims. All equivalent structural changes made using the contents of the description and drawings of the present invention should also be included in the protection scope of the present invention.

Claims

1. A composite combined electrical appliance suitable for extremely low temperature environment, comprising a tank circuit breaker, a current transformer and an isolating switch, wherein the tank circuit breaker comprises a circuit breaker tank, one end of the current transformer is connected to the circuit breaker tank, and characterized in that: The other end of the current transformer is connected to a transition cylinder, the isolating switch is connected to the other end of the transition cylinder, a heating air chamber connected to the inside of the circuit breaker tank is formed in the transition cylinder, and a cylinder heater is arranged on the transition cylinder.

2. The composite combination electrical appliance suitable for extremely low temperature environment according to claim 1, characterized in that: The barrel heater is an electric heating sleeve arranged outside the transition barrel.

3. The composite combined electrical appliance suitable for extremely low temperature environment according to claim 1 or 2, characterized in that: An in-tank electric heating rod is arranged in the circuit breaker tank body, and the electrode of the in-tank electric heating rod passes through the circuit breaker tank body and is insulated and sealed with the circuit breaker tank body.

4. The composite combined electrical appliance suitable for extremely low temperature environment according to claim 3, characterized in that: An insulator is arranged on the outside of the circuit breaker tank body at the position where the electrode of the electric heating rod in the tank passes through. The insulator includes a sealing disk that fits the outer wall of the circuit breaker tank body. A sealing ring is arranged between the sealing disk and the circuit breaker tank body. The electrode and the circuit breaker tank body are insulated and sealed by the insulator and the sealing ring.

5. The composite combined electrical appliance suitable for extremely low temperature environment according to claim 4, characterized in that: A groove adapted to the in-tank electric heating rod is provided on the inner side of the bottom of the circuit breaker tank body, and the in-tank electric heating rod is arranged in the groove.

6. The composite combined electrical appliance suitable for extremely low temperature environment according to claim 5, characterized in that: The bottom of the circuit breaker tank is provided with a thickened portion with thickened wall thickness, and the groove is opened on the thickened portion.

7. The composite combined electrical appliance suitable for extremely low temperature environment according to any one of claims 1, 2, 4-6, characterized in that: An electric heating sleeve is installed outside the circuit breaker tank.

8. The composite combined electrical appliance suitable for extremely low temperature environment according to claim 7, characterized in that: A tank heat insulation cover is arranged outside the circuit breaker tank.

9. The composite combined electrical appliance suitable for extremely low temperature environment according to claim 8, characterized in that: A cylinder heat insulation cover is arranged outside the transition cylinder.

10. The composite combined electrical appliance suitable for extremely low temperature environment according to claim 9, characterized in that: The cylinder heat insulation cover and the tank heat insulation cover are connected to each other as a whole.

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