Direct-current circuit breaker integrated with quick turn-off function and used for energy storage system

Abstract

The invention discloses an energy storage system direct current circuit breaker integrated with a rapid turn-off function, which comprises a shell, an operating mechanism, an electromagnetic release, a moving contact, a static contact, an arc extinguish chamber and an arc striking sheet, and further comprises a moving contact auxiliary acceleration mechanism, an elastic arc striking sheet, a movable permanent magnet magnetic blow-out intensifier and a rotary arc extinguishing blade. The moving contact auxiliary acceleration mechanism provides additional driving force through an energy storage torsion spring and an electromagnetic release sheet during short circuit, so that the breaking time is shortened; the elastic arc striking sheet actively captures the electric arc, and contact ablation is reduced; the movable permanent magnet magnetic blow-out intensifier automatically adjusts the magnetic field intensity according to the magnitude of current, and the magnetic blow-out effect is improved; the rotary arc extinguishing blades are driven by airflow to rotate, stir the airflow and cut residual arcs, and the arc extinguishing efficiency is improved. Through a multi-field coupling synergistic effect, the rapid turn-off capability, the breaking capability and the electric service life of the circuit breaker are remarkably improved, and the circuit breaker is suitable for a high-voltage and large-current energy storage system.

Description

Technical Field

[0001] This invention relates to the field of electrical device technology, and more specifically to a DC circuit breaker for an energy storage system with integrated fast shutdown function. Background Technology

[0002] DC miniature circuit breakers are a type of miniature circuit breaker used for overload protection, short-circuit protection, and infrequent switching of DC lines. With the rapid development of energy storage systems, communication power supplies, power systems, rail transportation, and other fields, the performance requirements for DC circuit breakers are constantly increasing.

[0003] Existing DC miniature circuit breakers (such as patent number 2022209620230) include a housing, operating mechanism, electromagnetic trip unit, moving contact, stationary contact, arc-extinguishing chamber, and arc-initiating plate, etc., and achieve arc guidance and extinguishing through the arc-initiating plate and arc-blocking magnetic blowout assembly. However, this type of structure still has the following drawbacks when facing the high voltage, high current, and rapid shutdown requirements of energy storage systems:

[0004] 1. Insufficient response speed of moving contact: The moving contact is driven only by the operating mechanism and lacks self-driving force in the early stage of short-circuit current rise, resulting in a long breaking time, which is difficult to meet the requirements of energy storage system for rapid shutdown.

[0005] 2. Limited arc ignition capability: The arc ignition angle structure on the stationary contact is simple, and the arc is prone to linger in the contact area, causing contact erosion. At the same time, the efficiency of transferring the arc to the arc extinguishing chamber is low.

[0006] 3. Limited magnetic blowing effect: Existing magnetic blowing components are mostly planar structures with uniform magnetic field distribution but insufficient strength, making it difficult to quickly blow the arc into the arc extinguishing chamber under high current.

[0007] 4. Low cooling efficiency of the arc-extinguishing chamber: The arc-extinguishing chamber grids are arranged in parallel, the arc path is short, and the contact with the grids is insufficient. High-temperature gas is easy to flow back to the contact area, affecting insulation recovery.

[0008] 5. Slow tripping response: The electromagnetic trip unit relies entirely on mechanical inertia and lacks a fast response mechanism to the rate of change of short-circuit current, which limits its fast shutdown performance. Summary of the Invention

[0009] To address the aforementioned technical problems, this invention provides a DC circuit breaker for energy storage systems with integrated fast shutdown function. Through multi-field coupling synergy, it significantly improves the circuit breaker's fast shutdown capability, breaking capacity, and electrical life, making it suitable for high-voltage, high-current energy storage systems and overcoming the technical problems in the prior art.

[0010] To achieve the above objectives, the present invention provides a DC circuit breaker for an energy storage system with integrated fast shutdown function, including a housing, an operating mechanism, an electromagnetic trip unit, a moving contact, a stationary contact, an arc-extinguishing chamber, and an arc-starting plate, and further including a moving contact auxiliary acceleration mechanism, which is disposed at the rotating shaft of the moving contact and is used to provide additional opening driving force to the moving contact during a short circuit.

[0011] As a further option, the moving contact auxiliary acceleration mechanism includes an energy storage torsion spring, a trigger latch, and an electromagnetic release plate;

[0012] The energy storage torsion spring is sleeved on the rotating shaft of the moving contact. One end of the spring is provided with a first hook that is inserted into and fixed in the first hanging hole on the moving contact, and the other end is provided with a second hook.

[0013] The trigger latch is a lever-type structure, rotatably mounted on the housing via a latch pivot. It includes a latch body, a hook-shaped portion at one end of the latch body, and a force-receiving arm at the other end of the latch body. The hook-shaped portion engages with the second hook to lock the energy storage torsion spring. The force-receiving arm is positioned opposite to the electromagnetic release plate. A reset torsion spring is fitted on the latch pivot to keep the trigger latch in its initial position.

[0014] The electromagnetic release plate is fixed to the housing, with one end close to the stationary contact.

[0015] When a short-circuit current passes through, the electromagnetic release plate is magnetized and attracts the force arm, driving the trigger latch to rotate, causing the hook-shaped part to disengage from the second hook, and the energy storage torsion spring to release elastic potential energy, driving the moving contact to open faster.

[0016] A DC circuit breaker for an energy storage system with integrated fast shutdown function includes a housing, an operating mechanism, an electromagnetic trip unit, a moving contact, a stationary contact, an arc-extinguishing chamber, and an arc-inducing plate. It also includes an elastic arc-inducing plate disposed on the stationary contact for actively capturing and guiding the electric arc.

[0017] As a further option, the elastic arc-guiding sheet is a long strip of elastic metal sheet, one end of which is a fixed end, fixed to the bent arc-guiding part of the stationary contact by a rivet, and the other end is a free end, which is attached to the surface of the bent arc-guiding part in a natural state; a limiting baffle is also provided above the bent arc-guiding part, and the limiting baffle is fixed to the housing to limit the maximum lifting height of the elastic arc-guiding sheet.

[0018] A DC circuit breaker for an energy storage system with integrated fast shutdown function includes a housing, an operating mechanism, an electromagnetic trip unit, a moving contact, a stationary contact, an arc-extinguishing chamber, and an arc-starting plate. It also includes a movable permanent magnet magnetic blowout enhancer, which is disposed on the magnetic conductive plate of the magnetic blowout assembly and is used to automatically adjust the magnetic field strength according to the current magnitude to enhance the magnetic blowout effect.

[0019] As a further option, the movable permanent magnet blowout enhancer includes a permanent magnet block, a swing bracket, and a reset component;

[0020] The swing bracket is U-shaped and made of non-magnetic stainless steel. Its two arms are swayably mounted on the bracket seat on the back of the magnetic sheet via pins. The permanent magnet block is embedded in the mounting groove at the bottom of the swing bracket, and its magnetic pole direction is perpendicular to the swing plane.

[0021] The reset component is a reset torsion spring sleeved on the pin shaft, with one end abutting against the swing bracket and the other end abutting against the housing, so that the swing bracket maintains its initial position when no external force is applied.

[0022] When a short-circuit current passes through, the magnetic field of the current interacts with the magnetic field of the permanent magnet block, driving the swing bracket to swing and bringing the permanent magnet block closer to the magnetic conductive sheet, thereby enhancing the magnetic field strength in the arc-initiating channel.

[0023] A DC circuit breaker for an energy storage system with integrated fast shutdown function includes a housing, an operating mechanism, an electromagnetic trip unit, a moving contact, a stationary contact, an arc-extinguishing chamber, and an arc-starting plate. It also includes a rotating arc-extinguishing blade, which is rotatably disposed in the arc-extinguishing chamber to agitate the airflow and cut off residual electric arc.

[0024] As a further option, the rotating arc-extinguishing blade includes a blade body and a rotating shaft;

[0025] The rotating shaft passes through the center of the blade body, and the rotation axis of the blade body is perpendicular to the mainstream direction of the gas in the arc-extinguishing chamber; both ends of the rotating shaft are mounted on the grid plates of the arc-extinguishing chamber through ceramic bearings.

[0026] The blade body is made of zirconia ceramic and is cross-shaped with four blades. Each blade has an array of hemispherical pits on its surface.

[0027] A DC circuit breaker for an energy storage system with integrated fast shutdown function is characterized by comprising the aforementioned moving contact auxiliary acceleration mechanism, elastic arc-inducing plate, movable permanent magnet magnetic blowout enhancer, and rotating arc-extinguishing blade.

[0028] As a further option, when a short-circuit fault occurs, the moving contact auxiliary acceleration mechanism drives the moving contact to open rapidly. The generated arc is actively captured and guided to the arc-initiating plate by the elastic arc-initiating plate. The strong magnetic field of the movable permanent magnet blowout enhancer quickly blows the arc into the arc-extinguishing chamber. The arc is divided by the grid plate in the arc-extinguishing chamber. At the same time, the rotating arc-extinguishing blades rotate and stir the airflow and cut the residual arc. Rapid shutdown is achieved through the synergistic effect of multi-field coupling.

[0029] Compared with the prior art, the beneficial effects of the present invention are:

[0030] 1. The energy storage torsion spring releases instantaneously during a short circuit, providing additional torque, which shortens the breaking time of the moving contact and makes the response faster.

[0031] 2. The elastic arc-starting plate is made of beryllium bronze and is directly fixed to the stationary contact. It is resistant to arc erosion, does not deform under repeated operation, actively captures and guides the arc, shortens the arc transfer time, and reduces the erosion of the main contact.

[0032] 3. The swing-type movable permanent magnet structure avoids sliding friction, ensuring reliable and jam-free operation. It automatically adjusts its position according to the current magnitude, increasing the magnetic blowing force, and requires no electronic control.

[0033] 4. The ceramic rotating arc-extinguishing blades are resistant to high temperatures and electrically insulating. The ceramic bearings are self-lubricating and maintenance-free. They agitate the airflow and cut off residual arcs, thus shortening the arc-extinguishing time and reducing the outlet temperature.

[0034] 5. The various structures work together to form a rapid shutdown system with electromagnetic, airflow, thermal, and mechanical four-field coupling, which improves the ultimate breaking capacity and extends the electrical life. Attached Figure Description

[0035] Figure 1 Internal structure diagram of the circuit breaker according to an embodiment of the present invention.

[0036] Figure 2 A structural diagram of the moving contact-assisted acceleration mechanism according to an embodiment of the present invention.

[0037] Figure 3 A structural diagram showing the separation of the energy storage torsion spring and the trigger latch in an embodiment of the present invention.

[0038] Figure 4 Front view of the elastic arc-inducing plate according to an embodiment of the present invention.

[0039] Figure 5 Top view of the elastic arc-drawing sheet in an embodiment of the present invention.

[0040] Figure 6 Rear view of the movable permanent magnet blowout enhancer according to an embodiment of the present invention.

[0041] Figure 7A front view of the rotating arc-extinguishing blade according to an embodiment of the present invention.

[0042] Figure 8 A bottom view of the rotating arc-extinguishing blade in an embodiment of the present invention.

[0043] Figure 9 of Figure 8 Enlarged structural diagram at point A.

[0044] In the diagram: 10. Housing; 11. Operating mechanism; 111. Handle; 112. Linkage mechanism; 113. Trigger; 12. Electromagnetic trip unit; 13. Moving contact; 131. Rotating shaft; 132. Conductive arm; 133. Moving contact end; 14. Stationary contact; 141. Stationary contact end; 142. Bending arc-initiating part; 15. Arc-extinguishing chamber; 151. Grid plate; 16. Arc-initiating plate; 20. Moving contact auxiliary acceleration mechanism; 21. Energy storage torsion spring; 211. First hook; 212. 22. Second hook; 22. Trigger latch; 221. Latch body; 222. Hook-shaped part; 223. Force arm; 224. Latch pivot; 23. Electromagnetic release plate; 30. Elastic arc-inducing plate; 31. Fixed end; 32. Rivet; 33. Limiting baffle; 40. Movable permanent magnet magnetic blow-out enhancer; 41. Magnetic guide plate; 412. Support base; 42. Permanent magnet block; 43. Swinging support; 50. Rotating arc-extinguishing blade; 51. Blade body; 511. Recess; 52. Pivot. Detailed Implementation

[0045] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0046] I. Overall Structure of Circuit Breaker

[0047] like Figure 1 As shown, this embodiment provides a DC circuit breaker for an energy storage system with integrated fast shutdown function, including a housing 10, an operating mechanism 11, an electromagnetic trip unit 12, a moving contact 13, a stationary contact 14, an arc-extinguishing chamber 15, and an arc-starting plate 16. These are conventional components of a circuit breaker, and their basic structure and function are as follows:

[0048] Housing 10: Made of insulating material (such as thermosetting plastic), it consists of a base and a top cover, with an internal cavity to accommodate the various functional components. Housing 10 is provided with inlet and outlet terminals (not shown in the figure) for connecting to external circuits.

[0049] Operating mechanism 11 includes handle 111, linkage mechanism 112, trip latch 113, etc., for manual opening and closing, and provides normal opening and closing driving force for moving contact 13.

[0050] Electromagnetic trip unit 12: includes an electromagnetic coil, an iron core, and a trip lever. When a short-circuit current passes through, the electromagnetic coil generates a strong magnetic field that drives the iron core to move, pushing the trip lever to release the trip, thus achieving short-circuit protection. The conventional structure will not be described in detail.

[0051] Moving contact 13: Rotatably mounted inside housing 10 via a pivot and connected to operating mechanism 11. Moving contact 13 includes a conductive arm 132 and a moving contact end 133 fixed to one end of the conductive arm.

[0052] Stationary contact 14: Fixedly installed inside the housing 10, opposite to the moving contact 13. The stationary contact 14 includes a stationary contact end 141 located at one end and a bent arc-inducing portion 142 extending from the stationary contact side toward the arc-extinguishing chamber.

[0053] Arc-extinguishing chamber 15: Located on one side of the stationary contact 14 and the moving contact 13, it is used to extinguish the electric arc. The arc-extinguishing chamber 15 is provided with multiple metal grid plates 151, which are arranged in parallel to divide the electric arc.

[0054] Arc-starting plate 16: a metal plate, fixed inside the housing 10 near the entrance of the arc-extinguishing chamber 15, used to guide the electric arc to the arc-extinguishing chamber.

[0055] The improvement of this invention lies in the addition of the following five functional components to the above-mentioned conventional structure: a moving contact auxiliary acceleration mechanism 20, an elastic arc-inducing plate 30, a movable permanent magnet magnetic blowout enhancer 40, and a rotating arc-extinguishing blade 50. These are described in detail below.

[0056] II. Moving contact auxiliary acceleration mechanism 20

[0057] like Figure 2 , Figure 3 As shown, the moving contact auxiliary acceleration mechanism 20 is located at the rotating shaft 131 of the moving contact 13, and includes an energy storage torsion spring 21, a trigger latch 22, and an electromagnetic release plate 23.

[0058] The energy storage torsion spring 21 is a torsion spring sleeved on the rotating shaft 131 of the moving contact 13. One end of the energy storage torsion spring 21 is provided with a first hook 211, which is inserted into a first hanging hole on the moving contact 13 body and fixedly connected. The other end of the energy storage torsion spring 21 is provided with a second hook 212, which is movably connected to the trigger latch 22. When the operating mechanism 11 presses the moving contact 13 onto the stationary contact 14, the energy storage torsion spring 21 is twisted by about 30°, storing sufficient elastic potential energy, but without affecting the normal closing holding force.

[0059] The trigger latch 22 is a lever-type structure, consisting of a latch body 221, a hook-shaped part 222, a force-receiving arm 223, and a latch shaft 224. The latch body 221 is rotatably mounted on the housing 10 via the latch shaft 224, located approximately 5 mm above and to the side of the moving contact shaft 131. One end of the latch body 221 has a hook-shaped part 222 with an inclined guide surface, which cooperates with the second hook 212 of the energy storage torsion spring 21 to hook the energy storage torsion spring 21 in the normal state, keeping it in an energy-storing state. The other end of the latch body 221 is a force-receiving arm 223, the end of which is positioned opposite to the electromagnetic release plate 23, one end of which is close to the stationary contact 14. The force-receiving arm 223 is made of non-magnetic stainless steel to avoid affecting the magnetic circuit of the electromagnetic release plate 23. A reset torsion spring is fitted on the locking shaft 224. One end of the reset torsion spring is fixed on the locking shaft 224, and the other end abuts against the housing 10, so that the trigger lock 22 keeps the hook-shaped part 222 facing the energy storage torsion spring 21 in the initial position when there is no external force.

[0060] The electromagnetic release plate 23 is made of electrical pure iron (soft magnetic material), is L-shaped, and is fixed to the housing 10 by insulating pads and screws. The electromagnetic release plate 23 extends upward and is opposite to the force-bearing arm 223 of the trigger latch 22, with a gap between them. The magnetic circuit design of the electromagnetic release plate 23 ensures that the magnetic attraction force generated under the rated short-circuit current (such as 1000A) is sufficient to overcome the resistance of the reset torsion spring and drive the trigger latch 22 to rotate, but the magnetic attraction force generated under normal load current is extremely small and will not cause false triggering.

[0061] When a short-circuit current passes through the stationary contact 14, the electromagnetic release plate 23 is magnetized, generating a magnetic force that attracts the force arm 223 of the trigger latch 22, causing the latch body 221 to rotate clockwise around the latch shaft 224. When the rotation angle reaches the set disengagement angle, such as 15°, the hook 222 disengages from the second hook 212 of the energy storage torsion spring 21. The energy storage torsion spring 21 is released instantaneously, and its stored elastic potential energy is converted into torque in a short time, driving the moving contact 13 to open rapidly, forming a double acceleration with the electromagnetic trip unit 12.

[0062] III. Elastic Arc-Striking Plate 30

[0063] like Figure 4 , Figure 5 As shown, the elastic arc-starting sheet 30 is disposed on the bent arc-starting portion 142 of the stationary contact 14, and preferably multiple sheets are disposed thereon, with identical mounting structures. The elastic arc-starting sheet 30 is an independent elastic metal sheet made of beryllium bronze alloy, with a thickness of approximately 0.25 mm, and its surface is silver-plated to improve conductivity.

[0064] The elastic arc-inducing piece 30 is elongated, approximately 12mm in length and 4mm in width. One end is a fixed end 31, which is directly fixed to the fixing hole on the bent arc-inducing part 142 by a rivet 32, forming a reliable mechanical and electrical connection. The rivet 32 ​​is made of copper and is flush with the surface of the bent arc-inducing part 142 after riveting.

[0065] The other end of the elastic arc-inducing piece 30 is a free end, which adheres to the upper surface of the bent arc-inducing part 142 in its natural state by its own elastic deformation force. The bending curvature of the elastic arc-inducing piece 30 is precisely designed to maintain a contact pressure of about 0.2N on the surface of the bent arc-inducing part 142, ensuring stable adhesion under normal conditions and preventing it from jumping up due to vibration.

[0066] On the upper surface of the bent arc-inducing part 142, corresponding to the position of the free end of the elastic arc-inducing piece 30, a shallow positioning groove is provided. The groove is shaped to match the free end and is used to accommodate the free end of the elastic arc-inducing piece 30, making its positioning more accurate and preventing lateral slippage.

[0067] Above the swing path of the free end of the elastic arc-inducing plate 30, a limiting baffle 33 made of alumina ceramic is provided and fixed to the housing 10. The limiting baffle 33 restricts the maximum lifting height of the elastic arc-inducing plate 30 to prevent it from undergoing excessive deformation and permanent plastic deformation.

[0068] When the moving contact 13 separates from the stationary contact 14 and generates an electric arc, the high temperature of the arc causes the surrounding air to expand rapidly, forming a high-speed airflow that impacts the elastic arc-starting plate 30. Simultaneously, the strong electric field generated by the arc also attracts the elastic arc-starting plate 30. Under the combined action of the airflow impact and the electric field, the elastic arc-starting plate 30 overcomes its own elasticity and springs off the surface of the bent arc-starting portion 142, actively facing the arc. Because the elastic arc-starting plate 30 is at the same potential as the stationary contact 14, the root of the arc easily transfers to the elastic arc-starting plate 30, thus quickly leaving the main contact area and shortening the transfer time. After the arc is extinguished, the elastic arc-starting plate 30 automatically resets due to its own elasticity, adhering back to the surface of the bent arc-starting portion 142, ready for the next action.

[0069] IV. Movable permanent magnet blowout enhancer 40

[0070] like Figure 6 As shown, the movable permanent magnet magnetic blowout enhancer 40 is disposed on the back of the magnetic guide plate 41 of the magnetic blowout assembly. The magnetic blowout assembly includes the magnetic guide plate 41, which is a conventional component made of stacked silicon steel sheets and is fixed to the inner wall of the housing 10, located on both sides of the arc ignition channel.

[0071] The movable permanent magnet blowout enhancer 40 includes a permanent magnet block 42, a swing bracket 43, and a reset torsion spring.

[0072] The swing bracket 43 is made of non-magnetic stainless steel and is U-shaped. Its two arms are swayably mounted on the bracket seat 412 on the back of the magnetic sheet 41 via pins. The bracket seat 412 consists of two bosses, which are integrally formed with the magnetic sheet 41 or fixed by screws. The bottom of the swing bracket 43 is provided with a mounting groove for fixing the permanent magnet block 42.

[0073] The permanent magnet block 42 is rectangular in shape and made of neodymium iron boron permanent magnet material with high magnetic energy product. It is embedded in the mounting groove of the swing bracket 43 and fixed with high-temperature resistant epoxy resin. The magnetic pole direction of the permanent magnet block 42 is perpendicular to the swing plane (e.g., the N pole faces outward from the paper and the S pole faces inward from the paper), so that the magnetic field can be effectively coupled to the magnetic conductive sheet 41.

[0074] The reset torsion spring is a torsion spring sleeved on the pin, with one end abutting the rear side of the swing bracket 43 and the other end abutting the spring seat on the housing 10. The elastic force of the reset torsion spring keeps the swing bracket 43 in a backward tilted position when no external force is applied, at which time the permanent magnet block 42 is about 5mm away from the back of the magnetic conductive sheet 41.

[0075] Preferably, a front limit post and a rear limit post (not shown in the accompanying drawings for conventional technology) are provided on the movement path of the swing bracket 43 to limit its maximum forward and backward swing angles, respectively. The front limit post and the rear limit post are copper cylinders and are fixed to the housing 10. The maximum forward swing angle is 20°, at which time the permanent magnet block 42 is in close contact with the back of the magnetic conductive sheet 41; the maximum backward swing angle is 15°.

[0076] Under normal operating current, the swing bracket 43 is tilted backward under the action of the reset torsion spring, and the permanent magnet block 42 is far away from the magnetic plate 41, having little impact on the magnetic field in the arc-starting channel. When a short-circuit current (e.g., 1000A) passes through the main circuit, the strong magnetic field generated by the current interacts with the magnetic field of the permanent magnet block 42, generating an electromagnetic torque pointing in the direction of the arc-starting channel. This torque overcomes the elastic force of the reset torsion spring, causing the swing bracket 43 to swing forward until it touches the front limit post. At this time, the permanent magnet block 42 is in close contact with the back of the magnetic plate 41, and its magnetic field is coupled into the arc-starting channel through the magnetic plate 41, increasing the magnetic field strength in the arc-starting channel (e.g., from 0.1T to 0.25T). When the current decreases or disappears, the reset torsion spring pushes the swing bracket 43 back to its original position.

[0077] V. Rotating arc-extinguishing blades 50

[0078] like Figures 7-9 As shown, the rotating arc-extinguishing blade 50 is disposed in the arc-extinguishing chamber 15, including the blade body 51 and the rotating shaft 52, located between the grid plate 151 group and the exhaust port, rotatably mounted on the grid plate 151, and distributed in the gap between adjacent grid plates 151.

[0079] The blade body 51 is made of zirconia ceramic, and is cruciform in shape with four blades, each approximately 15 mm long, 8 mm wide, and 2 mm thick. A shaft hole is located at the center of the blade body 51. Each blade surface has tiny hemispherical pits 511, 0.3 mm in diameter and 0.15 mm deep, arranged in an array to increase friction with the airflow and enhance the ability to capture electric arcs. Zirconia ceramic possesses excellent high-temperature resistance and electrical insulation properties, and will not be damaged by electric arc burning or cause phase-to-phase short circuits.

[0080] The rotating shaft 52 is made of stainless steel, with a diameter of 3 mm and a length of 20 mm, and its surface is polished. The rotating shaft 52 passes through the shaft hole of the blade body 51 and is clearance-fitted with the blade body 51, allowing the blade body 51 to rotate freely. Both ends of the rotating shaft 52 are mounted on the grid plates 151 via ceramic bearings. The ceramic bearings are self-lubricating zirconia bearings. The axial direction of the rotating shaft 52 is perpendicular to the mainstream direction of the gas in the arc-extinguishing chamber 15 (horizontally arranged), allowing the airflow to directly impact the blade 51.

[0081] A 1.5mm gap is left between the outer edge of the blade body 51 and the inner wall of the adjacent grid plate 151 to avoid jamming. A transparent observation window (not shown in the figure) can be provided on the side wall of the arc-extinguishing chamber 15 at the position corresponding to the blade body 51 to observe whether the blade is rotating normally.

[0082] When high-temperature, high-pressure gas rushes from the area of ​​the grid plate 151 towards the exhaust port, the airflow impacts the blades 51, causing the blade body 51 to rotate at high speed around the axis 52. The rotating blades produce the following multiple effects: stirring the airflow, ensuring that the residual electric arc comes into full contact with the grid plate 151 and the blade body 51, accelerating cooling; the rotating blades cut through the residual electric arc, further dividing the arc into smaller segments; the centrifugal force generated by the rotation throws metal vapor and free particles toward the inner wall of the arc-extinguishing chamber 15; and the sound waves generated by the rotating blades help promote ion recombination.

[0083] Complete Work Process Description

[0084] When a short-circuit fault occurs, all components work together to complete a rapid shutdown process:

[0085] Phase 1: Fault Detection and Pre-Triggering

[0086] When a short-circuit current flows through the conductive plate of the stationary contact 14, the electromagnetic release plate 23 is magnetized, generating a magnetic force that attracts the force arm 223 of the trigger latch 22. The trigger latch 22 rotates, releasing the energy storage torsion spring 21. At the same time, the electromagnetic coil of the electromagnetic trip unit 12 also detects the short-circuit current and begins to drive the iron core to move.

[0087] Second stage: Accelerated separation of moving contact

[0088] The energy storage torsion spring 21 is released instantaneously, providing a torque of approximately 0.15 N·m. During closing, the torsion spring is twisted, storing elastic potential energy. After the latch is released, the torsion spring returns to its equilibrium state. The restoring torque acts directly on the moving contact through the first hook, accelerating the opening of the moving contact 13. The iron core of the electromagnetic trip unit 12 pushes the trip lever to release the trip latch, and the operating mechanism 11 also drives the moving contact 13 to separate. The three mechanisms work together to completely separate the moving contact end 133 from the stationary contact end 141.

[0089] Phase 3: Arc Generation and Transfer

[0090] The separation of the moving and stationary contacts generates an electric arc. The high temperature of the arc causes the surrounding air to expand rapidly, forming a high-speed airflow that impacts the elastic arc-starting plate 30. Simultaneously, the electric field force causes the elastic arc-starting plate 30 to bounce off the bent arc-starting part 142 and actively meet the arc. The elastic arc-starting plate 30 captures the root of the arc, allowing the arc to quickly transfer from the main contact area to the arc-starting plate 16. The arc transfer time is short, and the ablation of the main contact is significantly reduced.

[0091] Phase 4: Magnetic Blowout Enhancement and Arc Guidance

[0092] The swing bracket 43 of the movable permanent magnet blowout enhancer 40 is attracted forward by the magnetic field of the current and swings forward. The permanent magnet block 42 approaches the magnetic conductive plate 41, which increases the magnetic field strength in the arc ignition channel from 0.1T to 0.25T. The enhanced magnetic field generates a strong magnetic blowing force, which pushes the arc to move rapidly along the arc ignition channel towards the arc extinguishing chamber 15.

[0093] Phase 5: Arc Segmentation and Cooling

[0094] After the electric arc enters the arc-extinguishing chamber 15, it is divided into multiple short arcs by the grid plates 151. When the high-temperature gas flows through the rotating arc-extinguishing blades 50, it impacts the blade body 51 and rotates at high speed. The rotating blades agitate the airflow, cut the residual electric arc, and ensure that the electric arc comes into full contact with the grid plates for cooling. The centrifugal force generated by the rotation throws the metal vapor toward the inner wall of the arc-extinguishing chamber, and the sound waves promote ion recombination.

[0095] Phase 6: Exhaust and Isolation

[0096] The cooled, high-temperature gas is discharged from the exhaust port.

[0097] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A DC circuit breaker for an energy storage system with integrated fast shutdown function, comprising a housing (10), an operating mechanism (11), an electromagnetic trip unit (12), a moving contact (13), a stationary contact (14), an arc-extinguishing chamber (15), and an arc-starting plate (16), characterized in that, It also includes a moving contact auxiliary acceleration mechanism (20), which is disposed at the pivot (131) of the moving contact (13) and is used to provide an additional opening driving force to the moving contact (13) in the event of a short circuit.

2. The DC circuit breaker for an energy storage system with integrated fast shutdown function according to claim 1, characterized in that, The moving contact auxiliary acceleration mechanism (20) includes an energy storage torsion spring (21), a trigger latch (22), and an electromagnetic release plate (23). The energy storage torsion spring (21) is sleeved on the rotating shaft (131) of the moving contact (13). One end of the spring is provided with a first hook (211) which is inserted into and fixed in the first hanging hole on the moving contact (13), and the other end is provided with a second hook (212). The trigger latch (22) is a lever-type structure, rotatably mounted on the housing (10) via a latch pivot (224). It includes a latch body (221), a hook-shaped part (222) at one end of the latch body (221), and a force-receiving arm (223) at the other end of the latch body (221). The hook-shaped part (222) cooperates with the second hook (212) to lock the energy storage torsion spring (21). The force-receiving arm (223) is arranged opposite to the electromagnetic release plate (23). A reset torsion spring is sleeved on the latch pivot (224) to keep the trigger latch (22) in its initial position. The electromagnetic release plate (23) is fixed on the housing (10), with one end close to the stationary contact (14). When a short-circuit current passes through, the electromagnetic release plate (23) is magnetized and attracts the force arm (223), driving the trigger latch (22) to rotate, causing the hook (222) to disengage from the second hook (212), and the energy storage torsion spring (21) releases elastic potential energy, driving the moving contact (13) to open faster.

3. A DC circuit breaker for an energy storage system with integrated fast shutdown function, comprising a housing (10), an operating mechanism (11), an electromagnetic trip unit (12), a moving contact (13), a stationary contact (14), an arc-extinguishing chamber (15), and an arc-starting plate (16), characterized in that, It also includes an elastic arc-guiding piece (30), which is disposed on the stationary contact (14) and is used to actively capture and guide the electric arc.

4. A DC circuit breaker for an energy storage system with integrated fast shutdown function according to claim 3, characterized in that, The elastic arc-leading piece (30) is a long strip of elastic metal sheet. One end is a fixed end (31), which is fixed to the bent arc-leading part (142) of the stationary contact (14) by a rivet (32). The other end is a free end, which is attached to the surface of the bent arc-leading part (142) in a natural state. A limiting baffle (33) is also provided above the bent arc-leading part (142). The limiting baffle (33) is fixed to the housing (10) and is used to limit the maximum lifting height of the elastic arc-leading piece (30).

5. A DC circuit breaker for an energy storage system with integrated fast shutdown function, comprising a housing (10), an operating mechanism (11), an electromagnetic trip unit (12), a moving contact (13), a stationary contact (14), an arc-extinguishing chamber (15), and an arc-starting plate (16), characterized in that, It also includes a movable permanent magnet magnetic blow-out enhancer (40), which is disposed on the magnetic conductive sheet (41) of the magnetic blow-out assembly and is used to automatically adjust the magnetic field strength according to the current magnitude to enhance the magnetic blow-out effect.

6. A DC circuit breaker for an energy storage system with integrated fast shutdown function according to claim 5, characterized in that, The movable permanent magnet blowout enhancer (40) includes a permanent magnet block (42), a swing bracket (43), and a reset component; The swing bracket (43) is U-shaped and made of non-magnetic stainless steel. Its two arms are swayably mounted on the bracket seat (412) on the back of the magnetic sheet (41) by means of pins. The permanent magnet block (42) is embedded in the mounting groove at the bottom of the swing bracket (43), and its magnetic pole direction is perpendicular to the swing plane. The reset component is a reset torsion spring sleeved on the pin shaft, with one end abutting against the swing bracket (43) and the other end abutting against the housing (10), so that the swing bracket (43) maintains its initial position when no external force is applied; When a short-circuit current passes through, the magnetic field of the current interacts with the magnetic field of the permanent magnet block (42), driving the swing bracket (43) to swing, so that the permanent magnet block (42) moves closer to the magnetic conductive sheet (41), thereby enhancing the magnetic field strength in the arc-starting channel.

7. A DC circuit breaker for an energy storage system with integrated fast shutdown function, comprising a housing (10), an operating mechanism (11), an electromagnetic trip unit (12), a moving contact (13), a stationary contact (14), an arc-extinguishing chamber (15), and an arc-starting plate (16), characterized in that, It also includes a rotating arc-extinguishing blade (50), which is rotatably disposed in the arc-extinguishing chamber (15) for stirring the airflow and cutting the residual electric arc.

8. A DC circuit breaker for an energy storage system with integrated fast shutdown function according to claim 7, characterized in that, The rotating arc-extinguishing blade (50) includes a blade body (51) and a rotating shaft (52); The rotating shaft (52) passes through the center of the blade body (51), and the rotation axis of the blade body (51) is perpendicular to the mainstream direction of the gas in the arc-extinguishing chamber (15); the two ends of the rotating shaft (52) are mounted on the grid plate (151) of the arc-extinguishing chamber (15) through ceramic bearings. The blade body (51) is made of zirconia ceramic and is cross-shaped with four blades. Each blade has an array of hemispherical pits (511) on its surface.

9. A DC circuit breaker for an energy storage system with integrated fast shutdown function, characterized in that, It includes the moving contact auxiliary acceleration mechanism (20) as described in claim 1, the elastic arc-inducing plate (30) as described in claim 3, the movable permanent magnet magnetic blow-out enhancer (40) as described in claim 5, and the rotating arc-extinguishing blade (50) as described in claim 7.

10. A DC circuit breaker for an energy storage system with integrated fast shutdown function according to claim 9, characterized in that, When a short circuit fault occurs, the moving contact auxiliary acceleration mechanism (20) drives the moving contact (13) to open rapidly. The generated arc is actively captured and guided to the arc-initiating plate (16) by the elastic arc-initiating plate (30). The movable permanent magnet magnetic blow-out enhancer (40) enhances the magnetic field and blows the arc into the arc-extinguishing chamber (15) quickly. The arc is divided by the grid plate (151) in the arc-extinguishing chamber (15). At the same time, the rotating arc-extinguishing blade (50) rotates and stirs the airflow and cuts the residual arc. Rapid shutdown is achieved through the synergistic effect of multi-field coupling.

Images