Rapid mechanical switch of bipolar direct-current circuit breaker

Abstract

The utility model relates to a quick mechanical switch of a bipolar direct current circuit breaker, which belongs to the field of quick mechanical switches and comprises a switch body, an electromagnetic repulsion operating mechanism, a driving circuit, a position detection unit and a control unit. The switch body comprises a vacuum arc-extinguishing chamber, at least one static contact and at least one moving contact, the direct current positive bus is provided with a positive switch fracture, the direct current negative bus is provided with a negative switch fracture, the static contacts are respectively arranged at two ends of the positive switch fracture and the negative switch fracture, and the moving contact is opposite to the static contacts; the control unit controls the driving circuit to drive the magnetic repulsion operating mechanism to switch on or switch off the rapid mechanical switch according to the switching-on state or the switching-off state, detected by the position detection unit, of the rapid mechanical switch. Reliable breaking of a direct-current bus fracture is realized through driving of the two series coils on the sides of the direct-current positive bus and the direct-current negative bus, the action consistency of a mechanical switch is improved, and the size and the cost of a product are reduced.

Description

Technical Field

[0001] The utility model belongs to the technical field of direct current switches, and in particular relates to a fast mechanical switch of a bipolar direct current circuit breaker. Background Art

[0002] With the rapid development of power grids, multi-terminal flexible DC transmission and distribution technology has been applied. DC circuit breakers are key equipment for building DC power grids, and play a role in grid connection and fault removal between converter valves. Most traditional DC circuit breakers are single-pole cabinet-type, but they have the defects of large overall footprint and high cost. Therefore, compact cabinet-type bipolar DC circuit breakers are a problem that needs to be solved to promote the development and application of high-voltage DC power grid technology. Utility Model Content

[0003] The utility model provides a fast mechanical switch suitable for a bipolar DC circuit breaker, which not only solves the problem of inconsistent action of the mechanical switch of the bipolar circuit breaker, but also reduces the volume of the device through compact arrangement.

[0004] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0005] A fast mechanical switch for a bipolar DC circuit breaker, comprising: a switch body, an electromagnetic repulsion operating mechanism, a drive circuit, a position detection unit and a control unit;

[0006] The switch body comprises a vacuum interrupter, at least one static contact and at least one moving contact, a DC positive busbar is provided with a positive switch break, a DC negative busbar is provided with a negative switch break, static contacts are respectively arranged at both ends of the positive switch break and the negative switch break, and the moving contact is opposite to the static contact;

[0007] The control unit controls the drive circuit to drive the magnetic repulsion operating mechanism to close or open the fast mechanical switch according to the closing state or opening state of the fast mechanical switch detected by the position detection unit.

[0008] Preferably, the electromagnetic repulsion operating mechanism comprises an opening coil, a closing coil, a metal repulsion disk and a pull rod, and the moving contact is arranged at the end of the pull rod.

[0009] Preferably, the opening coils include two, one opening coil is located on the DC positive bus side, and the other opening coil is located on the DC negative bus side, and the two opening coils are connected in series.

[0010] Preferably, the closing coils include two, one closing coil is located on the DC positive bus side, and the other closing coil is located on the DC negative bus side, and the two closing coils are connected in series.

[0011] Preferably, the opening coil is located on the DC positive bus or the DC negative bus side, the closing coil is located on the lower side of the opening coil, the metal repulsion disk is located between the opening coil and the closing coil, and the pull rod is fixed on the metal repulsion disk.

[0012] Preferably, there is an air gap between the positive switch breaks, the static contacts are located on both sides of the positive switch breaks, the static contacts on both sides of the positive switch breaks are separated by the air gap, and when the moving contact contacts the static contact, the moving contact contacts the static contacts on both sides of the positive switch breaks respectively to realize electrical conduction of the busbars on both sides of the positive switch breaks;

[0013] There is an air gap between the negative switch breaks, and the static contacts are located on both sides of the negative switch breaks. The static contacts on both sides of the negative switch breaks are separated by the air gap. When the moving contact contacts the static contact, the moving contact contacts the static contacts on both sides of the negative switch break respectively to realize electrical conduction of the busbars on both sides of the negative switch break.

[0014] Preferably, the driving circuit includes an opening driving circuit, a closing driving circuit and an opening buffer driving circuit;

[0015] The opening drive circuit is connected to two opening coils connected in series in the positive and negative fast mechanical switches, and the closing drive circuit and the opening buffer drive circuit are respectively connected to two closing coils connected in series in the positive and negative fast mechanical switches.

[0016] Preferably, when the opening drive circuit receives the opening signal from the control unit, the capacitor in the opening drive circuit discharges to the two opening coils connected in series, a pulse current flows through the opening coils, and an eddy current with the same direction as the opening coil current is induced in the metal repulsion disk, generating a first repulsive force to drive the metal repulsion disk to drive the pull rod and the moving contact to move away from the static contact to achieve the opening operation.

[0017] Preferably, when the closing drive circuit receives the closing signal from the control unit, the capacitor in the closing drive circuit discharges to the two closing coils connected in series, a pulse current flows through the closing coil, and an eddy current with the same direction as the closing coil current is induced in the metal repulsion disk, thereby generating a second repulsive force to drive the metal repulsion disk to drive the pull rod and the moving contact to move in the direction of the static contact to achieve the closing operation.

[0018] Preferably, the opening buffer drive circuit receives the opening buffer signal of the control unit, and the capacitor in the opening buffer drive circuit discharges to the two closing coils connected in series. A pulse current flows through the closing coil, and an eddy current with the same direction as the closing coil current is induced in the metal repulsion disk, thereby generating a third repulsive force, thereby realizing the mutual repulsion of the closing coil and the metal repulsion disk to realize the opening buffer operation.

[0019] Optionally, the fast closing operation process: first, the fast mechanical switch must be in the opening position, the detection unit uploads the opening position signal to the control unit, the control unit issues a command to turn on the thyristor of the closing drive circuit, and the capacitor in the closing drive circuit discharges to the two closing coils connected in series to generate a pulse current. The pulse current generates an alternating magnetic field around the two closing coils connected in series and generates reverse induced eddy currents on the metal disk; under the interaction of the magnetic field generated by the eddy current and the magnetic field of the opening coil, the two closing coils connected in series and the metal repulsion disk generate electromagnetic repulsion, and the metal disk drives the moving parts such as the pull rod and the moving contact to move in the direction of the opening coil, thereby completing the simultaneous closing of the bipolar busbar break mechanical switches.

[0020] Optionally, the fast opening operation process: first, the fast mechanical switch must be in the closing position, the detection unit uploads the closing position signal to the control unit, the control unit issues a command to turn on the thyristor of the opening drive circuit, and the capacitor in the opening drive circuit discharges to the two opening coils connected in series to generate a pulse current. The pulse current generates an alternating magnetic field around the two opening coils connected in series, and generates reverse induced eddy currents on the metal repulsion disk; under the interaction of the magnetic field generated by the eddy current and the magnetic field of the opening coil, the two opening coils in series and the metal repulsion disk generate electromagnetic repulsion, and the metal repulsion The disk drives the pull rod, moving contact and other moving parts to move toward the closing coil. When their stroke reaches the insulation opening distance required by the switch, the control unit sends an opening buffer command to turn on the thyristor of the opening buffer drive circuit, and the capacitor in the opening buffer drive circuit discharges to the two closing coils connected in series. At this time, the closing coil and the metal repulsion disk will also generate repulsive force to slow down the moving parts, thereby reducing the kinetic energy of the moving parts of the operating mechanism when they reach the opening position, greatly reducing rebound and overshoot, avoiding opening failure caused by rebound of the moving contact, and then completing the simultaneous opening of the bipolar busbar break mechanical switch.

[0021] Beneficial effects: The reliable disconnection of the DC bus break is achieved by driving the two series coils on the DC positive bus and DC negative bus sides, which improves the consistency of the mechanical switch action of the bipolar circuit breaker. At the same time, the compact layout reduces the size of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic diagram of the closing position of the fast mechanical switch provided by the utility model.

[0023] Figure 2 This is a schematic diagram of the opening position of the fast mechanical switch provided by the utility model.

[0024] The accompanying drawings are marked as follows: 1-positive switch break, 2-pull rod, 3-electromagnetic repulsion operating mechanism, 4-negative switch break, 5-opening coil, 6-metal repulsion disk, 7-closing coil, 8-position detection unit, 9-opening drive circuit, 10-closing drive circuit, 11-opening buffer drive circuit, and 12-control unit. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the utility model and are not used to limit the utility model. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model.

[0026] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element.

[0027] Implementation Example 1

[0028] The fast mechanical switch of the bipolar DC circuit breaker comprises a switch body, an electromagnetic repulsion operating mechanism 3 , a drive circuit, a position detection unit 8 and a control unit 12 .

[0029] The switch body is mainly composed of a vacuum interrupter, at least one static contact and at least one moving contact. One end of the static contact is connected to the busbar. Further, one end of the static contact is respectively connected to the positive busbar and the negative busbar. The moving contact is opposite to the static contact. Optionally, when the switch body is in the open position, the spacing between the moving contact and the static contact is 6-16mm.

[0030] The positive switch break 1 and the negative switch break 4 are closed by the movement of the moving contact toward the static contact or the contact between the moving contact and the static contact to bear the working current of the system. The positive switch break 1 and the negative switch break 4 are opened by the movement of the moving contact in the opposite direction of the static contact or the separation of the moving contact and the static contact.

[0031] The electromagnetic repulsion operating mechanism 3 includes an opening coil 5, a closing coil 7, a metal repulsion disk 6 and a pull rod 2. Optionally, the opening coil 5 and the closing coil 7 are wound with copper wire and are covered with epoxy insulation; optionally, the opening coil 5 and the closing coil 7 are wound with copper-aluminum alloy and are covered with epoxy insulation; the closing coil 7 and the opening coil 5 are used to generate or remove electromagnetic repulsion to push the metal repulsion disk 6 to move, and the metal repulsion disk 6 drives the pull rod 2 and the moving contact to move, so as to realize the opening and closing operation of the mechanical switch; optionally, the moving contact is arranged at the end of the pull rod 2, and the moving contact faces the static contact, or the moving contact faces the static contact. It is arranged on one side of the positive switch break 1 and the negative switch break 4; optionally, the static contacts are respectively arranged at both ends of the positive switch break 1 and the negative switch break 4. It can be understood that there is an air gap between the positive switch break 1, and the static contacts are located on both sides of the positive switch break 1. The static contacts on both sides of the positive switch break 1 are separated by the air gap. When the moving contact contacts the static contact, the moving contact contacts the static contacts on both sides of the positive switch break 1, respectively, so as to realize the electrical conduction of the busbars on both sides of the positive switch break 1;

[0032] Optionally, there is an air gap between the negative switch break 4, and the static contacts are located on both sides of the negative switch break 4. The static contacts on both sides of the negative switch break 4 are separated by the air gap. When the moving contact contacts the static contact, the moving contact contacts the static contacts on both sides of the negative switch break 4 respectively, thereby realizing electrical conduction of the busbars on both sides of the negative switch break 4.

[0033] The driving circuit comprises an opening driving circuit 9, a closing driving circuit 10 and an opening buffer driving circuit 11, wherein the opening driving circuit 9, the closing driving circuit 10 and the opening buffer driving circuit 11 are all composed of controllable transistors, capacitors and diodes.

[0034] The opening drive circuit 9 is connected to two opening coils 5 connected in series in the positive and negative fast mechanical switches, and the closing drive circuit 10 and the opening buffer drive circuit 11 are connected to two closing coils 7 connected in series in the positive and negative fast mechanical switches.

[0035] When the opening drive circuit 9 receives the opening signal from the control unit 12, the capacitor in the opening drive circuit 9 discharges to the two opening coils 5 connected in series, and a pulse current flows through the opening coils 5, inducing an eddy current in the metal repulsion disk 6 in the same direction as the current of the opening coil 5, thereby generating a first repulsive force to drive the metal repulsion disk 6 to drive the pull rod 2 and the moving contact to move in the direction of separation from the static contact, thereby realizing the opening operation.

[0036] When the closing drive circuit 10 receives the closing signal from the control unit 12, the capacitor in the closing drive circuit 10 discharges to the two closing coils connected in series, and a pulse current flows through the closing coil 7, inducing an eddy current in the metal repulsion disk 6 in the same direction as the current of the closing coil 7, thereby generating a second repulsive force to drive the metal repulsion disk 6 to drive the pull rod 3 and the moving contact to move in the direction of the combination with the static contact, thereby realizing the closing operation.

[0037] Optionally, when the opening drive circuit 9 is in opening operation, after a preset time, optionally, the preset time is 1-4 seconds, the opening buffer drive circuit 11 receives the opening buffer signal of the control unit 12, and the capacitor in the opening buffer drive circuit 11 discharges to the two closing coils 7 connected in series, and a pulse current flows through the closing coil 7, and an eddy current with the same direction as the current of the closing coil 7 is induced in the metal repulsion disk 6, thereby generating a third repulsive force, realizing mutual repulsion between the closing coil 7 and the metal repulsion disk 6, avoiding the huge impact force during opening causing instability of the opening, and realizing opening. Gate buffer operation; optionally, the third repulsion is 0.1-0.3 times the first repulsion; optionally, the third repulsion is 0.12 times the first repulsion; optionally, the third repulsion is 0.15 times the first repulsion; optionally, the third repulsion is 0.18 times the first repulsion; optionally, the third repulsion is 0.2 times the first repulsion; optionally, the third repulsion is 0.24 times the first repulsion; optionally, the third repulsion is 0.26 times the first repulsion; optionally, the third repulsion is 0.3 times the first repulsion.

[0038] The function of the position detection unit 8 is to detect the position signal of the moving contact and to feed back to the control unit 12 whether the fast mechanical switch is in the closed state or the open state.

[0039] Working principle: When the fast mechanical switch of the bipolar DC circuit breaker is closed for closing operation, the fast mechanical switch is in the opening position, and the position detection unit 8 uploads the opening position signal to the control unit 12. The control unit 12 issues an instruction to turn on the thyristor of the closing drive circuit 10. The capacitor in the closing drive circuit 10 discharges to the two closing coils 7 connected in series, generating a pulse current. The pulse current generates an alternating magnetic field around the two closing coils 7 connected in series, and generates induced eddy currents in the same direction on the metal disk. The two closing coils 7 connected in series and the metal repulsion disk 6 generate an electromagnetic second repulsion force. The metal repulsion disk 6 drives the pull rod 2 and the moving contact to move in the direction of the static contact, completing the simultaneous closing of the bipolar busbar break mechanical switch.

[0040] When the fast mechanical switch of the bipolar DC circuit breaker is closed for opening operation, the fast mechanical switch is in the closing position, the position detection unit 8 transmits the closing position signal to the control unit 12, the control unit 12 issues an instruction to turn on the thyristor of the opening drive circuit 9, and the capacitor in the opening drive circuit 9 discharges to the two opening coils 5 connected in series, generating a pulse current, the pulse current generates an alternating magnetic field around the two opening coils connected in series, and generates induced eddy currents in the same direction on the metal repulsion disk 6, the two opening coils 7 connected in series and the metal repulsion disk 6 generate an electromagnetic first repulsion, and the metal repulsion disk 6 drives the pull The rod 2 and the moving contact move away from the static contact. When their travel reaches the preset insulation opening distance of the switch, the control unit 12 issues a trip buffer instruction to turn on the thyristor of the trip buffer drive circuit 11, and the capacitor in the trip buffer drive circuit 11 discharges to the two closing coils 7 connected in series. At this time, the closing coil 7 and the metal repulsion disk 6 will generate a third repulsive force to decelerate the moving parts, thereby reducing the kinetic energy of the moving parts of the operating mechanism when they reach the trip position, greatly reducing rebound and overshoot, avoiding the rebound of the moving contact and causing the failure of the trip, and then completing the simultaneous trip of the bipolar busbar break mechanical switch.

[0041] Embodiment 2

[0042] This embodiment is an improvement on the first embodiment.

[0043] In the first embodiment, when the fast mechanical switch of the bipolar DC circuit breaker is closed for opening operation, the opening buffer drive circuit is driven only when the stroke reaches the preset insulation opening distance of the switch. At this time, the switch impact force has already impacted the switch body, so this embodiment improves it.

[0044] The preset insulation distance of the switch is set to K. Preferably, K is 5-50mm; optionally, K is 5mm; optionally, K is 8mm; optionally, K is 10mm; optionally, K is 15mm; optionally, K is 20mm; optionally, K is 25mm; optionally, K is 30mm; optionally, K is 35mm; optionally, K is 40mm; optionally, K is 45mm; optionally, K is 50mm.

[0045] When the fast mechanical switch of the bipolar DC circuit breaker is closed for opening operation, the fast mechanical switch is in the closing position, the position detection unit 8 transmits the closing position signal to the control unit 12, the control unit 12 issues an instruction to turn on the thyristor of the opening drive circuit 9, and the capacitor in the opening drive circuit 9 discharges to the two opening coils 5 connected in series, generating a pulse current, the pulse current generates an alternating magnetic field around the two opening coils connected in series, and generates the same-direction induced eddy current on the metal repulsion disk 6, the two opening coils 7 connected in series and the metal repulsion disk 6 generate an electromagnetic first repulsion, the metal repulsion disk 6 carries The moving pull rod 2 and the moving contact move away from the static contact. When the stroke of the pull rod 2 reaches 0.96K, the control unit 12 issues a trip buffer command to turn on the thyristor of the trip buffer drive circuit 11. The capacitor in the trip buffer drive circuit 11 discharges to the two closing coils 7 connected in series. At this time, the closing coil 7 and the metal repulsion disk 6 will generate a third repulsive force to decelerate the moving parts, thereby reducing the kinetic energy of the moving parts of the operating mechanism when they reach the trip position, greatly reducing rebound and overshoot, and avoiding the rebound of the moving contact leading to the failure of the trip, thereby completing the simultaneous trip of the bipolar busbar break mechanical switch. Optionally, the third repulsive force is 0.05-0.3 times the first repulsive force; optionally, the third repulsive force is 0.05 times the first repulsive force; optionally, the third repulsive force is 0.06 times the first repulsive force; optionally, the third repulsive force is 0.07 times the first repulsive force; optionally, the third repulsive force is 0.08 times the first repulsive force; optionally, the third repulsive force is 0.09 times the first repulsive force; optionally, the third repulsive force is 0.1 times the first repulsive force.

[0046] When the fast mechanical switch of the bipolar DC circuit breaker is closed for opening operation, the fast mechanical switch is in the closing position, the position detection unit 8 transmits the closing position signal to the control unit 12, the control unit 12 issues an instruction to turn on the thyristor of the opening drive circuit 9, and the capacitor in the opening drive circuit 9 discharges to the two opening coils 5 connected in series, generating a pulse current, the pulse current generates an alternating magnetic field around the two opening coils connected in series, and generates the same-direction induced eddy current on the metal repulsion disk 6, the two opening coils 7 connected in series and the metal repulsion disk 6 generate an electromagnetic first repulsion, the metal repulsion disk 6 carries The moving pull rod 2 and the moving contact move away from the static contact. When the stroke of the pull rod 2 reaches 0.95K, the control unit 12 issues a trip buffer command to turn on the thyristor of the trip buffer drive circuit 11. The capacitor in the trip buffer drive circuit 11 discharges to the two closing coils 7 connected in series. At this time, the closing coil 7 and the metal repulsion disk 6 will generate a third repulsive force to decelerate the moving parts, thereby reducing the kinetic energy of the moving parts of the operating mechanism when they reach the trip position, greatly reducing rebound and overshoot, and avoiding the failure of the trip caused by the rebound of the moving contact, thereby completing the simultaneous tripping of the bipolar busbar break mechanical switches. Optionally, the third repulsive force is 0.05-0.3 times the first repulsive force; optionally, the third repulsive force is 0.05 times the first repulsive force; optionally, the third repulsive force is 0.06 times the first repulsive force; optionally, the third repulsive force is 0.07 times the first repulsive force; optionally, the third repulsive force is 0.08 times the first repulsive force; optionally, the third repulsive force is 0.09 times the first repulsive force; optionally, the third repulsive force is 0.1 times the first repulsive force.

[0047] When the fast mechanical switch of the bipolar DC circuit breaker is closed for opening operation, the fast mechanical switch is in the closing position, the position detection unit 8 transmits the closing position signal to the control unit 12, the control unit 12 issues an instruction to turn on the thyristor of the opening drive circuit 9, and the capacitor in the opening drive circuit 9 discharges to the two opening coils 5 connected in series, generating a pulse current, the pulse current generates an alternating magnetic field around the two opening coils connected in series, and generates the same-direction induced eddy current on the metal repulsion disk 6, the two opening coils 7 connected in series and the metal repulsion disk 6 generate an electromagnetic first repulsion, the metal repulsion disk 6 carries The moving pull rod 2 and the moving contact move away from the static contact. When the stroke of the pull rod 2 reaches 0.94K, the control unit 12 issues a trip buffer instruction to turn on the thyristor of the trip buffer drive circuit 11, and the capacitor in the trip buffer drive circuit 11 discharges to the two closing coils 7 connected in series. At this time, the closing coil 7 and the metal repulsion disk 6 will generate a third repulsive force to decelerate the moving parts, thereby reducing the kinetic energy of the moving parts of the operating mechanism when they reach the trip position, greatly reducing rebound and overshoot, and avoiding the failure of the trip due to the rebound of the moving contact, thereby completing the simultaneous tripping of the bipolar busbar break mechanical switches. Optionally, the third repulsive force is 0.05-0.3 times the first repulsive force; optionally, the third repulsive force is 0.05 times the first repulsive force; optionally, the third repulsive force is 0.06 times the first repulsive force; optionally, the third repulsive force is 0.07 times the first repulsive force; optionally, the third repulsive force is 0.08 times the first repulsive force; optionally, the third repulsive force is 0.09 times the first repulsive force; optionally, the third repulsive force is 0.1 times the first repulsive force.

[0048] When the fast mechanical switch of the bipolar DC circuit breaker is closed for opening operation, the fast mechanical switch is in the closing position, the position detection unit 8 transmits the closing position signal to the control unit 12, the control unit 12 issues an instruction to turn on the thyristor of the opening drive circuit 9, and the capacitor in the opening drive circuit 9 discharges to the two opening coils 5 connected in series, generating a pulse current, the pulse current generates an alternating magnetic field around the two opening coils connected in series, and generates the same-direction induced eddy current on the metal repulsion disk 6, the two opening coils 7 connected in series and the metal repulsion disk 6 generate an electromagnetic first repulsion, the metal repulsion disk 6 carries The moving pull rod 2 and the moving contact move away from the static contact. When the stroke of the pull rod 2 reaches 0.92K, the control unit 12 sends a trip buffer instruction to turn on the thyristor of the trip buffer drive circuit 11, and the capacitor in the trip buffer drive circuit 11 discharges to the two closing coils 7 connected in series. At this time, the closing coil 7 and the metal repulsion disk 6 will generate a third repulsive force to decelerate the moving parts, thereby reducing the kinetic energy of the moving parts of the operating mechanism when they reach the trip position, greatly reducing rebound and overshoot, and avoiding the rebound of the moving contact leading to the failure of the trip, thereby completing the simultaneous trip of the bipolar busbar break mechanical switch. Optionally, the third repulsive force is 0.05-0.3 times the first repulsive force; optionally, the third repulsive force is 0.05 times the first repulsive force; optionally, the third repulsive force is 0.06 times the first repulsive force; optionally, the third repulsive force is 0.07 times the first repulsive force; optionally, the third repulsive force is 0.08 times the first repulsive force; optionally, the third repulsive force is 0.09 times the first repulsive force; optionally, the third repulsive force is 0.1 times the first repulsive force.

[0049] When the fast mechanical switch of the bipolar DC circuit breaker is closed for opening operation, the fast mechanical switch is in the closing position, the position detection unit 8 transmits the closing position signal to the control unit 12, the control unit 12 issues an instruction to turn on the thyristor of the opening drive circuit 9, and the capacitor in the opening drive circuit 9 discharges to the two opening coils 5 connected in series, generating a pulse current, the pulse current generates an alternating magnetic field around the two opening coils connected in series, and generates the same-direction induced eddy current on the metal repulsion disk 6, the two opening coils 7 connected in series and the metal repulsion disk 6 generate an electromagnetic first repulsion, the metal repulsion disk 6 carries The moving pull rod 2 and the moving contact move away from the static contact. When the stroke of the pull rod 2 reaches 0.9K, the control unit 12 sends a trip buffer instruction to turn on the thyristor of the trip buffer drive circuit 11, and the capacitor in the trip buffer drive circuit 11 discharges to the two closing coils 7 connected in series. At this time, the closing coil 7 and the metal repulsion disk 6 will generate a third repulsive force to decelerate the moving parts, thereby reducing the kinetic energy of the moving parts of the operating mechanism when they reach the trip position, greatly reducing rebound and overshoot, and avoiding the rebound of the moving contact causing the failure of the trip, thereby completing the simultaneous trip of the bipolar busbar break mechanical switch. Optionally, the third repulsive force is 0.05-0.3 times the first repulsive force; optionally, the third repulsive force is 0.05 times the first repulsive force; optionally, the third repulsive force is 0.06 times the first repulsive force; optionally, the third repulsive force is 0.07 times the first repulsive force; optionally, the third repulsive force is 0.08 times the first repulsive force; optionally, the third repulsive force is 0.09 times the first repulsive force; optionally, the third repulsive force is 0.1 times the first repulsive force.

[0050] When the fast mechanical switch of the bipolar DC circuit breaker is closed for opening operation, the fast mechanical switch is in the closing position, the position detection unit 8 transmits the closing position signal to the control unit 12, the control unit 12 issues an instruction to turn on the thyristor of the opening drive circuit 9, and the capacitor in the opening drive circuit 9 discharges to the two opening coils 5 connected in series, generating a pulse current, the pulse current generates an alternating magnetic field around the two opening coils connected in series, and generates the same-direction induced eddy current on the metal repulsion disk 6, the two opening coils 7 connected in series and the metal repulsion disk 6 generate an electromagnetic first repulsion, the metal repulsion disk 6 carries The moving pull rod 2 and the moving contact move away from the static contact. When the stroke of the pull rod 2 reaches 0.85K, the control unit 12 sends a trip buffer instruction to turn on the thyristor of the trip buffer drive circuit 11, and the capacitor in the trip buffer drive circuit 11 discharges to the two closing coils 7 connected in series. At this time, the closing coil 7 and the metal repulsion disk 6 will generate a third repulsive force to decelerate the moving parts, thereby reducing the kinetic energy of the moving parts of the operating mechanism when they reach the trip position, greatly reducing rebound and overshoot, and avoiding the rebound of the moving contact causing the failure of the trip, thereby completing the simultaneous trip of the bipolar busbar break mechanical switch. Optionally, the third repulsive force is 0.05-0.3 times the first repulsive force; optionally, the third repulsive force is 0.05 times the first repulsive force; optionally, the third repulsive force is 0.06 times the first repulsive force; optionally, the third repulsive force is 0.07 times the first repulsive force; optionally, the third repulsive force is 0.08 times the first repulsive force; optionally, the third repulsive force is 0.09 times the first repulsive force; optionally, the third repulsive force is 0.1 times the first repulsive force.

[0051] When the fast mechanical switch of the bipolar DC circuit breaker is closed for opening operation, the fast mechanical switch is in the closing position, the position detection unit 8 transmits the closing position signal to the control unit 12, the control unit 12 issues an instruction to turn on the thyristor of the opening drive circuit 9, and the capacitor in the opening drive circuit 9 discharges to the two opening coils 5 connected in series, generating a pulse current, the pulse current generates an alternating magnetic field around the two opening coils connected in series, and generates the same-direction induced eddy current on the metal repulsion disk 6, the two opening coils 7 connected in series and the metal repulsion disk 6 generate an electromagnetic first repulsion, the metal repulsion disk 6 carries The moving pull rod 2 and the moving contact move away from the static contact. When the stroke of the pull rod 2 reaches 0.8K, the control unit 12 issues a trip buffer instruction to turn on the thyristor of the trip buffer drive circuit 11, and the capacitor in the trip buffer drive circuit 11 discharges to the two closing coils 7 connected in series. At this time, the closing coil 7 and the metal repulsion disk 6 will generate a third repulsive force to decelerate the moving parts, thereby reducing the kinetic energy of the moving parts of the operating mechanism when they reach the trip position, greatly reducing rebound and overshoot, and avoiding the rebound of the moving contact leading to the failure of the trip, thereby completing the simultaneous trip of the bipolar busbar break mechanical switch. Optionally, the third repulsive force is 0.05-0.3 times the first repulsive force; optionally, the third repulsive force is 0.05 times the first repulsive force; optionally, the third repulsive force is 0.06 times the first repulsive force; optionally, the third repulsive force is 0.07 times the first repulsive force; optionally, the third repulsive force is 0.08 times the first repulsive force; optionally, the third repulsive force is 0.09 times the first repulsive force; optionally, the third repulsive force is 0.1 times the first repulsive force.

[0052] When the fast mechanical switch of the bipolar DC circuit breaker is closed for opening operation, the fast mechanical switch is in the closing position, the position detection unit 8 transmits the closing position signal to the control unit 12, the control unit 12 issues an instruction to turn on the thyristor of the opening drive circuit 9, and the capacitor in the opening drive circuit 9 discharges to the two opening coils 5 connected in series, generating a pulse current, the pulse current generates an alternating magnetic field around the two opening coils connected in series, and generates the same-direction induced eddy current on the metal repulsion disk 6, the two opening coils 7 connected in series and the metal repulsion disk 6 generate an electromagnetic first repulsion, the metal repulsion disk 6 carries The moving pull rod 2 and the moving contact move away from the static contact. When the stroke of the pull rod 2 reaches 0.75K, the control unit 12 sends a trip buffer instruction to turn on the thyristor of the trip buffer drive circuit 11, and the capacitor in the trip buffer drive circuit 11 discharges to the two closing coils 7 connected in series. At this time, the closing coil 7 and the metal repulsion disk 6 will generate a third repulsive force to decelerate the moving parts, thereby reducing the kinetic energy of the moving parts of the operating mechanism when they reach the trip position, greatly reducing rebound and overshoot, and avoiding the rebound of the moving contact causing the failure of the trip, thereby completing the simultaneous trip of the bipolar busbar break mechanical switch. Optionally, the third repulsive force is 0.05-0.3 times the first repulsive force; optionally, the third repulsive force is 0.05 times the first repulsive force; optionally, the third repulsive force is 0.06 times the first repulsive force; optionally, the third repulsive force is 0.07 times the first repulsive force; optionally, the third repulsive force is 0.08 times the first repulsive force; optionally, the third repulsive force is 0.09 times the first repulsive force; optionally, the third repulsive force is 0.1 times the first repulsive force.

[0053] When the fast mechanical switch of the bipolar DC circuit breaker is closed for opening operation, the fast mechanical switch is in the closing position, the position detection unit 8 transmits the closing position signal to the control unit 12, the control unit 12 issues an instruction to turn on the thyristor of the opening drive circuit 9, and the capacitor in the opening drive circuit 9 discharges to the two opening coils 5 connected in series, generating a pulse current, the pulse current generates an alternating magnetic field around the two opening coils connected in series, and generates the same-direction induced eddy current on the metal repulsion disk 6, the two opening coils 7 connected in series and the metal repulsion disk 6 generate an electromagnetic first repulsion, the metal repulsion disk 6 carries The moving pull rod 2 and the moving contact move away from the static contact. When the stroke of the pull rod 2 reaches 0.7K, the control unit 12 sends a trip buffer instruction to turn on the thyristor of the trip buffer drive circuit 11, and the capacitor in the trip buffer drive circuit 11 discharges to the two closing coils 7 connected in series. At this time, the closing coil 7 and the metal repulsion disk 6 will generate a third repulsive force to decelerate the moving parts, thereby reducing the kinetic energy of the moving parts of the operating mechanism when they reach the trip position, greatly reducing rebound and overshoot, and avoiding the rebound of the moving contact causing the failure of the trip, thereby completing the simultaneous trip of the bipolar busbar break mechanical switch. Optionally, the third repulsive force is 0.05-0.3 times the first repulsive force; optionally, the third repulsive force is 0.05 times the first repulsive force; optionally, the third repulsive force is 0.06 times the first repulsive force; optionally, the third repulsive force is 0.07 times the first repulsive force; optionally, the third repulsive force is 0.08 times the first repulsive force; optionally, the third repulsive force is 0.09 times the first repulsive force; optionally, the third repulsive force is 0.1 times the first repulsive force.

[0054] When the fast mechanical switch of the bipolar DC circuit breaker is closed for opening operation, the fast mechanical switch is in the closing position, the position detection unit 8 transmits the closing position signal to the control unit 12, the control unit 12 issues an instruction to turn on the thyristor of the opening drive circuit 9, and the capacitor in the opening drive circuit 9 discharges to the two opening coils 5 connected in series, generating a pulse current, the pulse current generates an alternating magnetic field around the two opening coils connected in series, and generates the same-direction induced eddy current on the metal repulsion disk 6, the two opening coils 7 connected in series and the metal repulsion disk 6 generate an electromagnetic first repulsion, the metal repulsion disk 6 carries The moving pull rod 2 and the moving contact move away from the static contact. When the stroke of the pull rod 2 reaches 0.65K, the control unit 12 sends a trip buffer instruction to turn on the thyristor of the trip buffer drive circuit 11, and the capacitor in the trip buffer drive circuit 11 discharges to the two closing coils 7 connected in series. At this time, the closing coil 7 and the metal repulsion disk 6 will generate a third repulsive force to decelerate the moving parts, thereby reducing the kinetic energy of the moving parts of the operating mechanism when they reach the trip position, greatly reducing rebound and overshoot, and avoiding the rebound of the moving contact causing the failure of the trip, thereby completing the simultaneous trip of the bipolar busbar break mechanical switch. Optionally, the third repulsion is 0.05-0.3 times the first repulsion; optionally, the third repulsion is 0.05 times the first repulsion; optionally, the third repulsion is 0.1 times the first repulsion; optionally, the third repulsion is 0.15 times the first repulsion; optionally, the third repulsion is 0.2 times the first repulsion; optionally, the third repulsion is 0.25 times the first repulsion; optionally, the third repulsion is 0.3 times the first repulsion.

[0055] It should be noted that the serial numbers of the embodiments of the present invention are only for description and do not represent the advantages or disadvantages of the embodiments.

[0056] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the specification and drawings of the present invention, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A fast mechanical switch for a bipolar DC circuit breaker, characterized in that: include: Switch body, electromagnetic repulsion operating mechanism, drive circuit, position detection unit and control unit; The switch body comprises a vacuum interrupter, at least one static contact and at least one moving contact, a DC positive busbar is provided with a positive switch break, a DC negative busbar is provided with a negative switch break, static contacts are respectively arranged at both ends of the positive switch break and the negative switch break, and the moving contact is opposite to the static contact; The control unit controls the drive circuit to drive the magnetic repulsion operating mechanism to close or open the fast mechanical switch according to the closing state or opening state of the fast mechanical switch detected by the position detection unit.

2. The fast mechanical switch according to claim 1, characterized in that: The electromagnetic repulsion operating mechanism comprises an opening coil, a closing coil, a metal repulsion disk and a pull rod, and the moving contact is arranged at the end of the pull rod.

3. The fast mechanical switch according to claim 2, characterized in that: The opening coils include two, one opening coil is located at the DC positive bus side, and the other opening coil is located at the DC negative bus side, and the two opening coils are connected in series.

4. The fast mechanical switch according to claim 2, characterized in that: The closing coils include two, one closing coil is located on the DC positive bus side, and the other closing coil is located on the DC negative bus side, and the two closing coils are connected in series.

5. The fast mechanical switch according to claim 2, characterized in that: The opening coil is located on the DC positive busbar or the DC negative busbar side, the closing coil is located on the lower side of the opening coil, the metal repulsion disk is located between the opening coil and the closing coil, and the pull rod is fixed on the metal repulsion disk.

6. The fast mechanical switch according to claim 2, characterized in that: There is an air gap between the positive switch breaks, the static contacts are located on both sides of the positive switch breaks, and the static contacts on both sides of the positive switch breaks are separated by the air gap. When the moving contact contacts the static contact, the moving contact contacts the static contacts on both sides of the positive switch breaks respectively to realize electrical conduction of the busbars on both sides of the positive switch breaks; There is an air gap between the negative switch breaks, and the static contacts are located on both sides of the negative switch breaks. The static contacts on both sides of the negative switch breaks are separated by the air gap. When the moving contact contacts the static contact, the moving contact contacts the static contacts on both sides of the negative switch break respectively to realize electrical conduction of the busbars on both sides of the negative switch break.

7. The fast mechanical switch according to claim 6, characterized in that: The drive circuit includes an opening drive circuit, a closing drive circuit and an opening buffer drive circuit; The opening drive circuit is connected to two opening coils connected in series in the positive and negative fast mechanical switches, and the closing drive circuit and the opening buffer drive circuit are respectively connected to two closing coils connected in series in the positive and negative fast mechanical switches.

8. The fast mechanical switch according to claim 7, characterized in that: The position detection unit is fixed to the end of the pull rod and is located at the lower side of the closing coil.

9. The fast mechanical switch according to claim 8, characterized in that: The closing drive circuit is connected in parallel with the opening buffer drive circuit.

10. The fast mechanical switch according to claim 9, characterized in that: The opening drive circuit, the closing drive circuit and the opening buffer drive circuit are electrically connected to the control unit respectively.

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