A pole mounted circuit breaker with built-in disconnect switch

Abstract

The present invention discloses a pole-mounted circuit breaker with a built-in isolating switch, comprising a three-phase insulating box in a sealed box, each phase insulating box is equipped with a direct-acting circuit breaker and a rotary isolating switch, the direct-acting circuit breaker comprises a moving contact rod, a vacuum arc extinguishing chamber and a stationary contact rod, the rotary isolating switch comprises a left gate seat, a knife switch and a right gate seat, the transmission mechanism comprises a synchronous shaft, an output crank arm, an insulating pull rod, an inclined track and a roller, the inclined track and the roller are located on the same side and the two can roll and cooperate after the moving contact rod and the stationary contact rod are separated, so that the knife switch and the right gate seat are separated. The present invention first controls the moving contact rod to open the gate, and after the moving contact rod is opened, the conductive disk and the conductive spring on the sliding cylinder are separated again, and finally, the inclined track on the sliding cylinder pushes the roller on one side of the knife switch to move, driving the knife switch to open, and realizing the opening of the isolating switch, which solves the problem of electric sparks / arcs when the isolating switch is opened due to insufficient arc extinguishing distance or linkage sliding.

Description

Technical Field

[0001] The invention relates to the technical field of vacuum circuit breakers, and in particular to a pole-mounted circuit breaker with a built-in isolating switch. Background Art

[0002] A pole-mounted circuit breaker refers to a circuit breaker installed and operated on an electric pole. The power research level and manufacturing technology of various circuit breakers have made great progress. Vacuum circuit breakers are not limited to medium-voltage power grids, but are developing towards high voltage and large capacity. Sulfur hexafluoride circuit breakers have many advantages, such as strong opening capacity, many continuous breaking times, frequent operation, low operating noise, no fire hazard, etc., and are a good oil-free equipment. Disconnectors are widely used in power systems, but affected by factors such as environmental pollution, manufacturing process, maintenance management, etc., disconnectors have serious rust, transmission difficulties, poor release, porcelain bottle breakage, poor sealing, etc. during operation, which pose serious safety hazards to power operation. At the same time, a large amount of manpower and material resources are required to maintain the disconnectors. A pole-mounted circuit breaker with a built-in disconnector is disclosed in the Chinese patent with publication number CN112216550A, which belongs to the technical field of power generation, substation or distribution. The circuit breaker switch, disconnector switch and their transmission mechanism are arranged in the same sealed box, wherein the circuit breaker switch includes an arc extinguishing chamber, a copper guide rod at the static end of the arc extinguishing chamber, and a contact spring assembly; the disconnector switch includes a moving contact and a static contact; the transmission mechanism includes a synchronous shaft, an output crank arm, an insulating pull rod, and a rotating assembly; and the entire main circuit is loaded in an insulating box. The invention can realize rapid mechanical linkage between the circuit breaker and the disconnector, and has the conditions for realizing a rapid reclosing function. Its defect is that the disconnector switch and the vacuum circuit breaker are linked, and relative sliding occurs between the moving contact and the static contact of the disconnector switch when the vacuum arc extinguishing chamber is opened, which is prone to electric sparks, aggravating the wear of the disconnector switch and shortening its service life. Summary of the invention

[0003] The present invention aims to solve the above problems existing in the prior art and provides a pole-mounted circuit breaker with a built-in isolating switch, which has good opening and closing sequence and prolongs the service life of the isolating switch.

[0004] The present invention solves the technical problem by adopting a technical solution: a pole-mounted circuit breaker with a built-in isolating switch, comprising a three-phase insulating box in a sealed box, each phase insulating box is equipped with a direct-acting circuit breaker and a rotary isolating switch, when the pole-mounted circuit breaker is in an open state and is ready to be closed, the transmission mechanism first pushes the rotary isolating switch to close, and then pushes the direct-acting circuit breaker to close, when the pole-mounted circuit breaker is in a closed state and is ready to be opened, the transmission mechanism first pulls the direct-acting circuit breaker to open, and then pulls the rotary isolating switch to open; the three-phase isolating switch is in an open state and is ready to be opened. Three incoming poles and three outgoing poles are respectively arranged on both sides of the box. The direct-acting circuit breaker comprises a moving contact rod, a vacuum interrupter and a static contact rod. The static contact rod is fixedly installed at one end of the vacuum interrupter, and the static contact rod is electrically connected to the outgoing pole. The other end of the vacuum interrupter is slidably sealed and connected to the moving contact rod. When the moving contact rod slides left and right, its inner end can contact or separate from the inner end of the static contact rod. A sliding cylinder is arranged at the outer end of the moving contact rod, and arc-extinguishing gas is arranged in the sliding cylinder. The rotary isolating switch comprises a left gate seat, a knife switch and a right gate seat. The left gate seat is electrically connected to the incoming line pole, one end of the knife switch is rotatably connected to the left gate seat and a reset spring is provided between the two. When the knife switch rotates, the other end of the knife switch can contact or separate from the right gate seat. The right gate seat is fixedly connected to a conductive rod, and the conductive rod is insulated and slidingly sealed with the sliding cylinder. A conductive disk is fixedly installed on the inner end of the conductive rod, and an air vent is provided on the conductive disk. An insulating shielding cylinder is fixedly installed on the inner cavity of the sliding cylinder, and the insulating shielding cylinder is slidably connected to the conductive disk. A conductive spring and an insulating spring are respectively provided between the left and right sides of the conductive disk and the sliding cylinder. The transmission mechanism includes a synchronous shaft, an output crank arm, an insulating pull rod, an inclined track and a roller. The output crank arm is fixedly installed on the synchronous shaft, one end of the insulating pull rod is rotatably connected to the output crank arm, and the other end of the insulating pull rod is rotatably connected to the sliding cylinder. The inclined track is fixedly installed on one side of the outer end of the sliding cylinder, and the roller is fixedly installed on the inner side of the knife switch. The inclined track and the roller are located on the same side and can roll and cooperate after the moving contact rod and the static contact rod are separated, so that the knife switch and the right gate seat are separated.

[0005] For further improvement, a heat dissipation tank is fixedly installed on the side wall of the box body, an impeller shaft is rotatably installed on the inner wall of the heat dissipation tank, the impeller shaft is connected to the rotating motor, the heat dissipation tank and the sliding cylinder are connected by a first insulating hose, and a heat sink fixedly connected to the heat dissipation tank is provided on the outer wall of the box body.

[0006] For further improvement, an insulating gas hood is provided outside the vacuum interrupter, two ends of the insulating gas hood are fixedly connected to two ends of the vacuum interrupter, and the insulating gas hood is connected to the heat dissipation gas tank through an insulating hard pipe.

[0007] Further improvement, the insulating gas hood and the sliding cylinder are connected through a second insulating hose.

[0008] For further improvement, the heat dissipation gas tank is provided with a temperature sensor, a deflation valve and a charging valve, and the charging valve is connected to the high-pressure gas storage bottle.

[0009] For further improvement, a main shielding cover is provided in the vacuum interrupter, and a permanent magnet is provided on each of the upper and lower inner walls of the main shielding cover, and the upper and lower permanent magnets are arranged with opposite poles.

[0010] For further improvement, an arc extinguishing grid assembly is respectively provided on the inner walls on the front and rear sides of the main shielding cover.

[0011] To be further improved, the arc extinguishing grid assembly is composed of several sub-arc extinguishing grids connected in series with an arc extinguishing mesh belt, the arc extinguishing mesh belt and the sub-arc extinguishing grids are fixedly connected, the sub-arc extinguishing grids and the main shielding cover are slidably connected, an insulating lever is fixedly connected between the left end of the arc extinguishing mesh belt and the moving contact rod, and the right end of the arc extinguishing mesh belt is fixedly connected to the main shielding cover.

[0012] Compared with the prior art, the beneficial effects of the present invention are as follows: during the opening process, the present invention controls the sliding cylinder of the direct-acting circuit breaker through the transmission mechanism to drive the moving contact rod to open the circuit breaker. After the moving contact rod is opened, the conductive disk on the sliding cylinder moves further and then separates from the conductive spring again, thereby increasing the arc extinguishing distance of the circuit breaker and enhancing the arc extinguishing ability. Finally, the inclined track on the sliding cylinder pushes the roller on one side of the knife switch to move, driving the knife switch to open, and realizing the opening of the disconnector, solving the problem of electric sparks / arcs caused by insufficient arc extinguishing distance or linkage sliding when the disconnector is opened, and extending its service life; during the closing process, the knife switch, the conductive disk and the moving contact rod are closed in sequence, and the safety is good. The opening and closing sequence of the present invention is good, the service life of the disconnector is extended, and the installation performance of the equipment is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a structural schematic diagram of the present invention in a closed state;

[0014] Figure 2 for Figure 1 An enlarged schematic diagram of the structure of the middle sliding cylinder;

[0015] Figure 3 It is a schematic diagram of the structure of the present invention in the open state;

[0016] Description of the accompanying drawings: 1. Box, 11. Three-phase insulation box, 12. Inlet pole, 13. Outlet pole, 14. Heat dissipation tank, 141. Impeller shaft, 142. Rotating motor, 143. First insulating hose, 144. Heat sink, 145. Temperature sensor, 146. Air release valve, 147. Inflating valve, 148. High-pressure gas storage bottle, 15. Insulating gas cover, 151. Insulating hard pipe, 152. Second insulating hose, 2. Direct-acting circuit breaker, 21. Moving contact rod, 22. True Empty arc extinguishing chamber, 23. Stationary contact rod, 24. Sliding cylinder, 25. Main shielding cover, 26. Permanent magnet, 3. Rotary isolating switch, 31. Left gate seat, 32. Knife switch, 33. Right gate seat, 34. Reset spring, 35. Conductive rod, 351. Conductive disk, 352. Air vent, 353. Conductive spring, 354. Insulating spring, 36. Insulating shielding cylinder, 4. Transmission mechanism, 41. Synchronous shaft, 42. Output crank arm, 43. Insulating pull rod, 44. Inclined track, 45. Roller. DETAILED DESCRIPTION

[0017] The present invention will be further described below in conjunction with the accompanying drawings:

[0018] Refer to the attached Figure 1-3In the present embodiment 1, a pole-mounted circuit breaker with a built-in isolating switch comprises a three-phase insulating box 11 in a sealed box body 1, wherein a direct-acting circuit breaker 2 and a rotary isolating switch 3 are installed in each phase insulating box, wherein the direct-acting circuit breaker 2 and the rotary isolating switch 3 are connected in series and asynchronously through a transmission mechanism 4, wherein when the pole-mounted circuit breaker is in an open state and is ready to be closed, the transmission mechanism 4 first pushes the rotary isolating switch 3 to close, and then pushes the direct-acting circuit breaker 2 to close, and when the pole-mounted circuit breaker is in a closed state and is ready to be opened, the transmission mechanism 4 first pulls the direct-acting circuit breaker to open, and then pulls the rotary isolating switch 3 to open; three are respectively provided on both sides of the three-phase insulating box 11. The direct-acting circuit breaker 2 includes a moving contact rod 21, a vacuum interrupter 22 and a static contact rod 23. The static contact rod 23 is fixedly installed at one end of the vacuum interrupter 22, and the static contact rod 23 is electrically connected to the outgoing pole 13. The other end of the vacuum interrupter 22 is slidably and sealedly connected to the moving contact rod 21. When the moving contact rod 21 slides left and right, its inner end can contact or separate from the inner end of the static contact rod 23. A sliding cylinder 24 is provided at the outer end of the moving contact rod 21, and arc extinguishing gas is provided in the sliding cylinder 24. The rotary disconnector 3 includes a left gate seat 31, a knife switch 32 and a right gate seat 33. The left gate seat 31 is connected to the incoming line The pole 12 is electrically connected, one end of the knife switch 32 is rotatably connected to the left gate seat 31 and a reset spring 34 is provided between the two. When the knife switch 32 rotates, the other end thereof can contact or separate from the right gate seat 33. The right gate seat 33 is fixedly connected to a conductive rod 35, and the conductive rod 35 is insulated and slidably sealed with the sliding cylinder 24. A conductive disk 351 is fixedly installed at the inner end of the conductive rod 35, and a vent hole 352 is provided on the conductive disk 351. An insulating shielding cylinder 36 is fixedly installed on the inner cavity of the sliding cylinder 24, and the insulating shielding cylinder 36 is slidably connected to the conductive disk 351. Conductive springs are respectively provided between the left and right sides of the conductive disk 351 and the sliding cylinder 24. 353 and an insulating spring 354, the transmission mechanism 4 includes a synchronous shaft 41, an output crank arm 42, an insulating pull rod 43, an inclined track 44 and a roller 45, the output crank arm 42 is fixedly mounted on the synchronous shaft 41, one end of the insulating pull rod 43 is rotatably connected to the output crank arm 42, the other end of the insulating pull rod 43 is rotatably connected to the sliding cylinder 24, the inclined track 44 is fixedly mounted on one side of the outer end of the sliding cylinder 24, the roller 45 is fixedly mounted on the inner side of the knife gate 32, the inclined track 44 and the roller 45 are located on the same side and the two can roll together after the moving contact rod 21 and the static contact rod 23 are separated, so that the knife gate 32 and the right gate seat 33 are separated.

[0019] Working principle: The incoming pole 12 and the outgoing pole 13 are connected to the external high-voltage circuit, and the synchronous shaft 41 rotates under the drive of the external operating mechanism. When performing the opening operation, the synchronous shaft 41 drives the output crank arm 42 to rotate counterclockwise, and the output crank arm 42 pushes the sliding cylinder 24 to move left through the insulating pull rod 43. The moving contact rod 21 moves left with the sliding cylinder 24 and separates from the static contact rod 23. A vacuum arc is generated between the moving contact rod 21 and the static contact rod 23. The vacuum arc is maintained by the metal vapor evaporated from the contact. When the power frequency current passes through zero, the metal vapor will stop evaporating. At the same time, the plasma of the vacuum arc quickly spreads to the surroundings, the arc is extinguished, and the contact gap quickly becomes an insulator, so the current is disconnected. When a vacuum arc is generated, the conductive rod 35 and the conductive disk 351 move rightward relative to the sliding cylinder 24, the conductive spring 353 stretches and continuously contacts the conductive disk 351 and finally separates, thereby increasing the arc extinguishing distance of the circuit breaker and enhancing the arc extinguishing ability. The arc extinguishing gas can improve the insulation performance inside the sliding cylinder 24, and the insulating spring 354 compresses and blocks the insulation between the right side of the conductive disk 351 and the sliding cylinder 24. Finally, the inclined track 44 on the sliding cylinder 24 pushes the roller 45 on one side of the knife switch 32 to move, driving the knife switch 32 to open, thereby realizing the opening of the disconnector, solving the problem of electric sparks / arcs generated when the disconnector is opened due to insufficient arc extinguishing distance or linkage sliding, and extending its service life. When performing the opening operation, the synchronous shaft 41 drives the output crank arm 42 to rotate clockwise, and the output crank arm 42 pushes the sliding cylinder 24 to move rightward through the insulating pull rod 43, and the knife switch, the conductive disk and the moving contact rod are closed in turn to realize the closing process, which is safe. The switch opening and closing method of the present invention has good sequence, prolongs the service life of the isolating switch and improves the installation performance of the equipment.

[0020] Embodiment 2 is different from Embodiment 1 only in that a heat dissipation tank 14 is fixedly provided on the side wall of the housing 1, an impeller shaft 141 is rotatably installed on the inner wall of the heat dissipation tank 14, the impeller shaft 141 is connected to a rotating motor 142, the heat dissipation tank 14 is connected to the sliding cylinder 24 through a first insulating hose 143, and a heat sink 144 fixedly connected to the heat dissipation tank 14 is provided on the outer wall of the housing 1. The rotating motor 142 drives the impeller shaft 141 to rotate, so that the arc-extinguishing gas in the heat dissipation tank 14 and the arc-extinguishing gas in the sliding cylinder 24 can exchange gas, maintain the insulation performance inside the sliding cylinder 24, and heat exchange can be performed when the gas flows through the heat sink 144, so that the arc-extinguishing gas can have a lower temperature.

[0021] Embodiment 3, on the basis of embodiment 2, an insulating gas cover 15 is provided outside the vacuum interrupter 22, and the two ends of the insulating gas cover 15 are fixedly connected to the two ends of the vacuum interrupter 22, and the insulating gas cover 15 is connected to the heat dissipation gas tank 14 through an insulating hard pipe 151. When an arc is generated in the vacuum interrupter 22, a large amount of heat is generated. After the heat is absorbed by the gas in the insulating gas cover 15, it can flow into the heat dissipation gas tank 14 for heat dissipation, thereby cooling the vacuum interrupter 22 and improving the arc extinguishing ability of the vacuum interrupter 22. The insulating gas cover 15 is connected to the sliding cylinder 24 through a second insulating hose 152, which can further establish a gas circulation loop and improve the heat dissipation ability.

[0022] Embodiment 4, on the basis of embodiment 2, the heat dissipation tank 14 is provided with a temperature sensor 145, a deflation valve 146 and a charging valve 147, and the charging valve 147 is connected to a high-pressure gas cylinder 148. The temperature sensor 145 can detect the gas temperature inside the heat dissipation tank and feed it back to the controller, which then adjusts the speed of the rotating motor 142. The deflation valve 146 can be opened to deflate when the gas pressure inside the heat dissipation tank 14 is too high, thereby quickly reducing the temperature of the heat dissipation tank and improving safety performance. When the charging valve 147 is opened, the high-pressure gas cylinder 148 can replenish the heat dissipation tank 14 with new arc extinguishing gas. The arc extinguishing gas generally uses sulfur hexafluoride, which is a colorless, odorless, non-toxic, non-corrosive, non-flammable, and non-explosive gas at normal temperature and pressure, and its density is about 5 times that of air.

[0023] Embodiment 5 is different from Embodiment 1 only in that a main shielding cover 25 is provided in the vacuum arc extinguishing chamber 22, and a permanent magnet is provided on each of the upper and lower inner walls of the main shielding cover 25. The upper and lower permanent magnets are arranged with opposite poles to form a directional magnetic field. When an arc is generated, the magnetic field generates an Ampere force on the arc to promote the breaking of the arc. An arc extinguishing grid assembly is provided on each of the front and rear inner walls of the main shielding cover 25, which can divide a large arc into small arcs when it hits, thereby improving the arc extinguishing efficiency.

[0024] Embodiment 6, on the basis of embodiment 5, the arc extinguishing grid assembly is composed of a plurality of sub-arc extinguishing grids connected in series with an arc extinguishing mesh belt, the arc extinguishing mesh belt and the sub-arc extinguishing grid are fixedly connected, the sub-arc extinguishing grid and the main shielding cover are slidably connected, an insulating lever is fixedly connected between the left end of the arc extinguishing mesh belt and the moving contact rod, and the right end of the arc extinguishing mesh belt and the main shielding cover are fixedly connected. When the moving contact rod is opened, the insulating lever pulls the arc extinguishing mesh belt to pull apart the sub-arc extinguishing grids, further improving the arc segmentation capability of the arc extinguishing grid. When the moving contact rod is closed, the insulating lever pulls the arc extinguishing mesh belt to gather the sub-arc extinguishing grids together.

[0025] Although the present invention has been shown and described with reference to preferred embodiments, it will be understood by those skilled in the art that various changes in form and details may be made therein within the scope of the claims.

Claims

1. A pole-mounted circuit breaker with a built-in isolating switch, comprising a three-phase insulating box (11) in a sealed box (1), each phase insulating box being equipped with a direct-acting circuit breaker (2) and a rotary isolating switch (3); when the pole-mounted circuit breaker is in an open state and is ready to be closed, a transmission mechanism (4) first pushes the rotary isolating switch (3) to close, and then pushes the direct-acting circuit breaker (2) to close; when the pole-mounted circuit breaker is in a closed state and is ready to be opened, the transmission mechanism (4) first pulls the direct-acting circuit breaker to open, and then pulls the rotary isolating switch (3) to open; Features: Three incoming poles (12) and three outgoing poles (13) are respectively provided on both sides of the three-phase insulation box (11); the direct-acting circuit breaker (2) comprises a moving contact rod (21), a vacuum interrupter (22) and a stationary contact rod (23); one end of the vacuum interrupter (22) is fixedly mounted with the stationary contact rod (23); the stationary contact rod (23) is electrically connected to the outgoing pole (13); the other end of the vacuum interrupter (22) is slidably sealed and connected to the moving contact rod (21); when the moving contact rod (21) slides left and right, its inner end and the inner end of the stationary contact rod (23) come into contact with or separate from each other; the moving contact rod (21) A sliding cylinder (24) is provided at the outer end thereof, arc extinguishing gas is provided in the sliding cylinder (24), the rotary disconnector (3) comprises a left gate seat (31), a knife switch (32) and a right gate seat (33), the left gate seat (31) is electrically connected to the incoming line pole (12), one end of the knife switch (32) is rotatably connected to the left gate seat (31) and a reset spring (34) is provided between the two, when the knife switch (32) rotates, the other end of the knife switch (32) contacts or separates from the right gate seat (33), the right gate seat (33) is fixedly connected to a conductive rod (35), and the conductive rod (35) is insulated and slidably connected to the sliding cylinder (24). Dynamic sealing connection, a conductive disk (351) is fixedly installed on the inner end of the conductive rod (35), and a vent hole (352) is provided on the conductive disk (351); an insulating shielding cylinder (36) is fixedly installed on the inner cavity of the sliding cylinder (24), and the insulating shielding cylinder (36) is slidably connected to the conductive disk (351); a conductive spring (353) and an insulating spring (354) are respectively provided between the left and right sides of the conductive disk (351) and the sliding cylinder (24); and the transmission mechanism (4) includes a synchronous shaft (41), an output crank arm (42), an insulating pull rod (43), an inclined track (44) and a roller (45), the output crank arm (42) is fixedly mounted on the synchronous shaft (41), one end of the insulating pull rod (43) is rotatably connected to the output crank arm (42), the other end of the insulating pull rod (43) is rotatably connected to the sliding cylinder (24), the inclined track (44) is fixedly mounted on one side of the outer end of the sliding cylinder (24), the roller (45) is fixedly mounted on the inner side of the knife switch (32), the inclined track (44) and the roller (45) are located on the same side and the two roll together after the moving contact rod (21) and the static contact rod (23) are separated, so that the knife switch (32) and the right gate seat (33) are separated.

2. A pole mounted circuit breaker with a built-in disconnect switch according to claim 1, Features: A heat dissipation tank (14) is fixedly arranged on the side wall of the box body (1), an impeller shaft (141) is rotatably mounted on the inner wall of the heat dissipation tank (14), the impeller shaft (141) is connected to a rotating motor (142), the heat dissipation tank (14) and the sliding cylinder (24) are connected via a first insulating hose (143), and a heat sink (144) fixedly connected to the heat dissipation tank (14) is arranged on the outer wall of the box body (1).

3. A pole mounted circuit breaker with a built-in disconnect switch according to claim 2, Features: An insulating gas cover (15) is provided outside the vacuum interrupter (22), two ends of the insulating gas cover (15) are fixedly connected to two ends of the vacuum interrupter (22), and the insulating gas cover (15) and the heat dissipation gas tank (14) are connected via an insulating hard pipe (151).

4. A pole mounted circuit breaker with a built-in disconnect switch according to claim 3, Features: The insulating gas hood (15) and the sliding cylinder (24) are connected via a second insulating hose (152).

5. A pole mounted circuit breaker with a built-in disconnect switch according to claim 2, Features: The heat dissipation gas tank (14) is provided with a temperature sensor (145), a gas release valve (146) and a gas charging valve (147), and the gas charging valve (147) is connected to a high-pressure gas storage bottle (148).

6. A pole mounted circuit breaker with a built-in disconnect switch according to claim 1, Features: A main shielding cover (25) is provided in the vacuum interrupter (22), and a permanent magnet is provided on each of the upper and lower inner walls of the main shielding cover (25), and the upper and lower permanent magnets are arranged with opposite poles.

7. A pole mounted circuit breaker with a built-in disconnect switch according to claim 6, Features: An arc extinguishing grid assembly is respectively provided on the inner walls on the front and rear sides of the main shielding cover (25).

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