Topology and breaking method of zero-zone transverse magnetic reinforcement high current circuit breaker

Abstract

Disclosed are a topology structure and a breaking method of a zero-zone transverse magnetic field reinforced large-current circuit breaker, wherein the fast vacuum switch comprises a static contact and a dynamic contact, the static contact and the dynamic contact are separated to generate plasma, a transverse magnetic coil is close to the static contact and the dynamic contact to excite a transverse magnetic field between the contact gaps thereof to accelerate the dissipation of the zero-zone plasma, and the transverse magnetic coil is used in series in a transfer module; the transfer module is connected in parallel to the fast vacuum switch via an auxiliary switch; and a current limiting module is connected in parallel to the transfer module. The structure can enhance the post-arc medium recovery capability of the fast vacuum switch, improve the reliability of the fast breaking of the generator source fault current, has the advantages of strong breaking capacity, fast breaking speed, complete environmental friendliness and the like, and can meet the operation requirements of a large-scale power generation system.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power equipment, and particularly relates to a topology structure of a zero-zone transverse magnetic field reinforced large-current circuit breaker. BACKGROUND

[0002] The short-circuit current at the outlet of a generator usually contains a huge direct current component, and the current delay zero phenomenon is prone to occur. The short-circuit current peak is high, and can reach a large current of 190 kA or more, so that the requirement for the breaking performance of the circuit breaker is high. The generator outlet circuit breaker is arranged between the outlet of the generator and the step-up transformer, and is core power equipment for ensuring the safe and stable operation of the generator set. The traditional current transfer breaking technology can force the current to drop to zero, but under the action of high-frequency transferred current, the current rate of change is large, the zero-zone residual plasma is difficult to dissipate in time, and the probability of arc afterburning is increased, which is not conducive to the breaking of the super-large short-circuit current.

[0003] The information disclosed in the background section is only used to enhance the understanding of the background of the present application, and therefore can contain information that does not constitute prior art known to those of ordinary skill in the art. SUMMARY

[0004] In view of the deficiencies or defects in the prior art, a topology structure of a zero-zone transverse magnetic field reinforced large-current circuit breaker is provided. In the process of rapid current transfer, a transverse magnetic field is synchronously applied to the contact system of a rapid vacuum switch to accelerate the dissipation of zero-zone residual plasma, improve the reliability of short-circuit current breaking, and has the advantages of large breaking capacity, high breaking reliability, fast breaking speed and the like, and can better meet the operation requirements of a large-scale power generation system. The large current refers to a current of 190 kA or more.

[0005] The purpose of the present application is achieved by the following technical solutions.

[0006] A topology structure of a zero-zone transverse magnetic field reinforced large-current circuit breaker comprises,

[0007] A zero-zone transverse magnetic field reinforced vacuum switch module comprises,

[0008] A rapid vacuum switch comprises a static contact and a moving contact, and the static contact and the moving contact are separated to generate plasma,

[0009] A transverse magnetic coil is arranged close to the static contact and the moving contact to excite a transverse magnetic field at the contact gap thereof to accelerate the dissipation of zero-zone plasma, and the transverse magnetic coil is reused in series in a transfer module;

[0010] A transfer module is connected in parallel to the rapid vacuum switch via an auxiliary switch;

[0011] A current limiting module is connected in parallel to the transfer module.

[0012] The topological structure of the zero-zone transverse magnetic reinforced large current circuit breaker, the static contact and the moving contact adopt cup-shaped longitudinal magnetic structure contact.

[0013] The topological structure of the zero-zone transverse magnetic reinforced large current circuit breaker, the static contact includes,

[0014] The static conductive rod,

[0015] The static end contact cup is connected with the static conductive rod, and the static end contact cup is provided with a first inclined groove inclined towards a predetermined inclined direction,

[0016] The static end contact piece is arranged at one end of the static end contact cup relative to the static conductive rod,

[0017] The moving contact includes,

[0018] The moving conductive rod,

[0019] The moving end contact cup is connected with the moving conductive rod, and the moving end contact cup is provided with a second inclined groove inclined towards the predetermined inclined direction,

[0020] The moving end contact piece is arranged at one end of the moving end contact cup relative to the moving conductive rod, and the moving end contact piece and the static end contact piece are switched between contact and separation, and when the current flows through the static end contact cup, the vacuum arc and the moving end contact cup, a longitudinal magnetic field diffusing the vacuum arc is generated in the gap between the static contact and the moving contact.

[0021] The topological structure of the zero-zone transverse magnetic reinforced large current circuit breaker, the transfer module includes a transfer capacitor and a transfer inductor arranged in series at one end of the transverse magnetic coil, and a thyristor assembly arranged at the other end of the transverse magnetic coil, the thyristor assembly includes a thyristor T1 and a thyristor T2 in reverse parallel connection.

[0022] The topological structure of the zero-zone transverse magnetic reinforced large current circuit breaker, the fast vacuum switch is driven by a fast operating mechanism, and the fast operating mechanism includes an electromagnetic operating mechanism and a spring operating mechanism.

[0023] The topological structure of the zero-zone transverse magnetic reinforced large current circuit breaker, the current limiting resistor includes any one or a combination of more than one of a ceramic resistor, an aluminum shell resistor and a cement resistor.

[0024] The topological structure of the zero-zone transverse magnetic reinforced large current circuit breaker, the auxiliary switch includes any one or a combination of more than one of a vacuum switch, an air switch and a power electronic switch.

[0025] The breaking method of the topological structure of the zero-zone transverse magnetic reinforced large current circuit breaker includes the following steps,

[0026] Step S100: when the fault current drops to the first characteristic value, a trip command is sent to the fast vacuum switch;

[0027] Step S200: when the fault current drops to the second characteristic value, the thyristor assembly is triggered, the transfer module releases the transfer current to the fast vacuum switch, the current of the fast vacuum switch drops rapidly, the direct current component decays, an artificial zero point is made, at the same time, the transfer current flows through the transverse magnetic coil, a transverse magnetic field is synchronously applied between the contact gaps of the fast vacuum switch, the zero area residual plasma is accelerated to dissipate, and the post-arc medium recovery capability is enhanced;

[0028] Step S300: the fast vacuum switch is opened at zero, the thyristor assembly is cut off at zero, the fault current is limited by the current limiting module, a trip command is sent to the auxiliary switch, and the fault current is cut off.

[0029] A computer storage medium, the storage medium comprising computer instructions, when running on a computer, make the computer execute the method.

[0030] An electronic device, the electronic device comprising:

[0031] A memory, a processor and a computer program stored on the memory and executable on the processor, wherein,

[0032] The processor implements the method when executing the program.

[0033] Compared with the prior art, the present application has the beneficial effects that:

[0034] The present application realizes the fast current transfer, the zero area transverse magnetic field reinforced zero crossing and the current limiting by controlling the fast vacuum switch action and then triggering the transfer module according to a specific time sequence, and finally completes the fault current interruption. The fast limitation and interruption of the delayed zero crossing of the generator source short-circuit current are realized. In the fast current transfer process, the transverse magnetic field is applied to the contact gap of the fast vacuum switch by the transverse magnetic coil, the dissipation of the zero area residual plasma is accelerated, and the withstand capability of the post-arc transient recovery voltage is enhanced. The fast vacuum interruption technology is used to replace the traditional SF6 interruption technology, and the present application has the completely environment-friendly characteristics.

[0035] The description is only a summary of the technical scheme of the present application, in order to make the technical means of the present application more clear and understandable, to the extent that the content of the description can be implemented by the person skilled in the art, and in order to make the said and other purposes, features and advantages of the present application more obvious and easy to understand, the specific embodiments of the present application are exemplified below. BRIEF DESCRIPTION OF DRAWINGS

[0036] Various other advantages and benefits of the present application will become apparent to those of ordinary skill in the art, upon reading the following detailed description of the preferred embodiment. The accompanying drawings are included to provide a better understanding of the preferred embodiment, and are not intended to limit the scope of the application. It should be readily understood that the drawings are not to scale, and are merely intended to be illustrative, the scope of the present application being defined by the appended claims. Moreover, where the same reference numerals are used in different figures, such reference numerals are intended to refer to the same or similar components throughout the different figures.

[0037] In the drawings:

[0038] Figure 1 is a schematic diagram of a circuit breaker topology for large current delayed zero switching according to an embodiment of the present application;

[0039] Figure 2 is a schematic diagram of a cup-shaped contact structure of a fast vacuum switch and its self-generated longitudinal magnetic field according to an embodiment of the present application;

[0040] Fig. 3(a) is a schematic diagram of current flow in a fast vacuum switch according to an embodiment of the present application when the contacts are closed;

[0041] Fig. 3(b) is a schematic diagram of a vacuum arc generated after the contacts of a fast vacuum switch according to an embodiment of the present application are pulled apart;

[0042] Fig. 3(c) is a schematic diagram of the movement of a vacuum arc in a fast vacuum switch according to an embodiment of the present application after a transverse magnetic field is applied to the contact gap;

[0043] Fig. 4(a) is a schematic diagram of a normal current flow phase of the circuit breaker shown in Fig. 1; Figure 1 Fig. 4(b) is a schematic diagram of the operation of the circuit breaker shown in Fig. 1 to initiate arcing and transfer zero;

[0044] Figure 1 Fig. 4(c) is a schematic diagram of a current limiting phase of the circuit breaker shown in Fig. 1;

[0045] Fig. 4(d) is a schematic diagram of a successful interruption phase of the circuit breaker shown in Fig. 1; Figure 1

[0046] Fig. 5 is a schematic diagram of the waveforms of the circuit breaker shown in Fig. 1 interrupting a forward short circuit current; Figure 1

[0047] Fig. 6 is a schematic diagram of the waveforms of the circuit breaker shown in Fig. 1 interrupting a reverse short circuit current; Figure 5 Figure 1

[0048] Figure 6 Figure 1

[0049] Figure 7 ​​​​​​It is another embodiment of the present application to provide a topology diagram based on vacuum multi-break parallel connection.

[0050] The present application will be further explained with reference to the accompanying drawings and embodiments. DETAILED DESCRIPTION

[0051] The specific embodiments of the present application will be described below in reference to the accompanying drawings. Although specific embodiments of the present application are shown in the drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments described herein. Rather, these embodiments are provided to enable a more thorough understanding of the present application and to fully convey the scope of the present application to those skilled in the art.

[0052] It should be noted that certain terms are used throughout the present specification and claims which have particular meanings as set forth below. Those skilled in the art will understand that not all instances can be listed, but those listed are intended to encompass all such or similar words falling within the same meaning. The present specification and claims are not to be limited by the difference in terms, but by the difference in functionality. As used throughout the present specification and claims, the term "comprising" or "including" is an open term, which should be construed to cover a "comprising but not limited to" situation. The subsequent description is provided as a preferred embodiment of implementing the present application, and is intended to serve the purpose of illustrating the general principles of the present application, but not to limit the scope of the present application. The scope of the present application is defined by the appended claims.

[0053] For the convenience of understanding the embodiments of the present application, the following will be further explained and described with reference to several specific embodiments as examples in conjunction with the accompanying drawings, and each of the accompanying drawings does not constitute a limitation to the embodiments of the present application.

[0054] For a better understanding, Figures 1 to 7 as shown in the drawings, a topology structure of a zero-zone transverse magnetic reinforced high current circuit breaker includes,

[0055] a zero-zone transverse magnetic reinforced vacuum switch module, which includes,

[0056] a fast vacuum switch, which includes a static contact and a dynamic contact, and the static contact and the dynamic contact separate to generate plasma,

[0057] a transverse magnetic coil, which is close to the static contact and the dynamic contact to excite a transverse magnetic field at a contact gap thereof to accelerate the dissipation of zero-zone plasma, and the transverse magnetic coil is reused in a transfer module in series;

[0058] a transfer module, which is connected in parallel to the fast vacuum switch via an auxiliary switch;

[0059] a current limiting module, which is connected in parallel to the transfer module.

[0060] In the preferred embodiment of the topology of the zero-zone transverse magnetic reinforced high current circuit breaker, the static contact and the moving contact both adopt cup-shaped longitudinal magnetic structure contact.

[0061] In the preferred embodiment of the topology of the zero-zone transverse magnetic reinforced high current circuit breaker, the static contact includes,

[0062] The static conductive rod,

[0063] The static end contact cup is connected to the static conductive rod, and the static end contact cup is provided with a first inclined groove inclined towards a predetermined inclined direction,

[0064] The static end contact piece is arranged at one end of the static end contact cup relative to the static conductive rod,

[0065] The moving contact includes,

[0066] The moving conductive rod,

[0067] The moving end contact cup is connected to the moving conductive rod, and the moving end contact cup is provided with a second inclined groove inclined towards the predetermined inclined direction,

[0068] The moving end contact piece is arranged at one end of the moving end contact cup relative to the moving conductive rod, and the moving end contact piece and the static end contact piece are switched between contact and separation, and when the current flows through the static end contact cup, the vacuum arc and the moving end contact cup, a longitudinal magnetic field that diffuses the vacuum arc is generated in the gap between the static contact and the moving contact.

[0069] In the preferred embodiment of the topology of the zero-zone transverse magnetic reinforced high current circuit breaker, the transfer module includes a transfer capacitor and a transfer inductor arranged in series at one end of the transverse magnetic coil, and a thyristor assembly arranged at the other end of the transverse magnetic coil, the thyristor assembly including a thyristor T1 and a thyristor T2 in reverse parallel connection.

[0070] In the preferred embodiment of the topology of the zero-zone transverse magnetic reinforced high current circuit breaker, the fast vacuum switch is driven by a fast operating mechanism, and the fast operating mechanism includes an electromagnetic operating mechanism and a spring operating mechanism.

[0071] In the preferred embodiment of the topology of the zero-zone transverse magnetic reinforced high current circuit breaker, the current limiting resistor includes any one or a combination of ceramic resistors, aluminum shell resistors, and cement resistors.

[0072] In the preferred embodiment of the topology of the zero-zone transverse magnetic reinforced high current circuit breaker, the auxiliary switch includes any one or a combination of vacuum switches, air switches, and power electronic switches.

[0073] The breaking method of the topology of the zero-zone transverse magnetic reinforced high current circuit breaker includes the following steps,

[0074] Step S100: sending a breaking instruction to the fast vacuum switch when the fault current drops to a first characteristic value;

[0075] Step S200: triggering the thyristor assembly when the fault current drops to a second characteristic value, the transfer module releases a transfer current to the fast vacuum switch, the current of the fast vacuum switch drops rapidly, the direct current component decays, an artificial zero point is made, at the same time, the transfer current flows through the transverse magnetic coil, a transverse magnetic field is synchronously applied between the contact gaps of the fast vacuum switch, the dissipation of the zero region residual plasma is accelerated, and the post-arc medium recovery capability is enhanced;

[0076] Step S300: the fast vacuum switch is opened at zero, the thyristor assembly is cut off at zero, the fault current is limited by the current limiting module, a breaking instruction is sent to the auxiliary switch, and the breaking of the fault current is completed.

[0077] A computer storage medium, the storage medium comprising computer instructions, when running on a computer, causes the computer to execute the method.

[0078] An electronic device, the electronic device comprising:

[0079] a memory, a processor, and a computer program stored on the memory and executable on the processor, wherein,

[0080] the processor implements the method when executing the program.

[0081] In one embodiment, a topology of a zero region transverse magnetic field reinforced high current circuit breaker comprises,

[0082] a zero region transverse magnetic field reinforced vacuum switch module comprising,

[0083] a fast vacuum switch comprising a static contact and a moving contact, the static contact and the moving contact adopt a cup-shaped longitudinal magnetic structure,

[0084] a transverse magnetic coil, the transverse magnetic coil is close to the contact system of the fast vacuum switch and is reused in the transfer module in series;

[0085] a transfer module, the transfer module is connected in parallel with the fast vacuum switch through an auxiliary switch;

[0086] a current limiting module, the current limiting module is connected in parallel with the transfer module. After forced transfer zero of the fast vacuum switch, due to the extremely high current change rate before zero, the residual plasma in the contact gap cannot be completely dissipated, the post-arc medium recovery capability is reduced, and the fast vacuum switch is easily broken down and reignited by the transient recovery voltage. The topology of the zero region transverse magnetic field reinforced high current circuit breaker can accelerate the dissipation speed of the zero region residual plasma, enhance the medium recovery capability of the fast vacuum switch after forced zero, improve the breaking reliability of the traditional current transfer type circuit breaker, and meet the protection requirements at the outlet of a large generator.

[0087] In the preferred embodiment of the topology, the transverse magnetic coil is connected in series with the loop formed by the transfer capacitor, the transfer inductor and the thyristor assembly, which can reuse the transfer current to apply a transverse magnetic field in the contact system of the fast vacuum switch.

[0088] The breaking method of the topology of the zero-zone transverse magnetic reinforcement type high-current circuit breaker comprises the following steps:

[0089] Step S100: When the fault current drops to a first characteristic value, send a breaking instruction to the fast vacuum switch S1.

[0090] Step S200: When the fault current drops to a second characteristic value, trigger the thyristor assembly, and the transfer module releases the transfer current to the fast vacuum switch S1, the current of the fast vacuum switch S1 drops rapidly, the direct current component decays, and an artificial zero point is created. At the same time, the transfer current flows through the transverse magnetic coil L1, and a transverse magnetic field is synchronously applied to the contact gap of the fast vacuum switch S1, accelerating the dissipation of the zero-zone residual plasma and enhancing the post-arc medium recovery capability.

[0091] Step S300: The fast vacuum switch S1 breaks at zero, the thyristor assembly turns off at zero, the fault current is limited by the current limiting module, a breaking instruction is sent to the auxiliary switch S2, and the fault current breaking is completed.

[0092] In the preferred embodiment of the breaking method, in step S100, when the fault current drops to the first characteristic value, a breaking instruction is sent to the fast vacuum switch S1. The first characteristic value ensures that the moving contact and the stationary contact of the fast vacuum switch reach a certain opening distance when the current transfer zero-crossing, which can withstand the post-arc transient recovery voltage in cooperation with the transverse magnetic field of the zero-zone.

[0093] In the preferred embodiment of the breaking method, in step S200, when the fault current drops to the second characteristic value, a conduction instruction is sent to the thyristor assembly, and the transfer capacitor C and the inductor oscillate to generate high-frequency transfer current. To ensure that the current of the fast vacuum switch S1 can reliably produce a zero-crossing point, the second characteristic value needs to be less than the peak value of the transfer current, and should have a margin of 5kA~10kA. At the same time, considering the time required for the action of the relay protection and the action of the power electronic device, the time from the second characteristic value to the minimum value of the fault current cannot be too short to ensure that a zero-crossing point is generated before the minimum value of the fault current.

[0094] In one embodiment, a topology structure is shown in Figure 1, including a zero region transverse magnetic reinforcement type vacuum switch module, a transfer module, a current limiting module and an auxiliary switch S2, the transfer module is connected in parallel between the two ends of the zero region transverse magnetic reinforcement type vacuum switch module through the auxiliary switch S2, and the current limiting module is connected in parallel between the two ends of the transfer module. Wherein, the zero region transverse magnetic reinforcement type vacuum switch module includes a fast vacuum switch S1 and a transverse magnetic coil L1; the transfer module includes a transfer capacitor C, a transfer inductor L2 and thyristor components T1 and T2, and the transverse magnetic coil L1 is reused in the transfer module; the current limiting module includes a current limiting resistor R. In the embodiment of the present application, the fast vacuum switch adopts a cup-shaped longitudinal magnetic contact, as shown in Figure 2, which includes a static contact cup 1, a static contact piece 2, a moving contact piece 3, a moving contact cup 4, a static conductive rod 5 and a moving conductive rod 6. Wherein, the static contact cup 1 and the moving contact cup 4 are provided with inclined grooves in the same direction, when the current flows through the static contact cup 1-vacuum arc 8-moving contact cup 4, a longitudinal magnetic field 7 is generated in the gap between the moving and static contacts, under the action of the longitudinal magnetic field, the vacuum arc 8 presents a diffusion state, which can reduce the local ablation of the contact surface, and is beneficial to improve the current breaking capacity of the vacuum switch.

[0095] In the embodiment of the present application, in the current transfer process, a transverse magnetic field is applied to the contact gap of the fast vacuum switch by the transverse magnetic coil to improve the post-arc medium recovery capability.

[0096] In the normal current flowing state, as shown in Figure 3(a), the moving contact and the static contact are in close contact, and the current flows from one end to the other end. After the fault occurs, the fast vacuum switch receives the opening instruction, the moving contact starts to move, the contact gap generates vacuum arc plasma, which is mainly composed of a large number of electrons, ions and metal particles, under the action of the longitudinal magnetic field generated in the contact cup, the vacuum arc presents a diffusion state, as shown in Figure 3(b). When the transfer module releases the transfer current, the current of the fast vacuum switch decreases rapidly, and at the same time, the transverse magnetic coil applies a transverse magnetic field to the contact gap, which drives the vacuum arc to move to one side of the contact, as shown in Figure 3(c), the micro-particles of the plasma quickly fly away from the contact gap under the action of the transverse magnetic field, accelerating the plasma dissipation process. When the current reaches zero, the amount of residual plasma in the contact gap is very low, and the post-arc medium recovery capability of the fast vacuum switch is improved.

[0097] In the embodiment of the present application, the topology structure of the high current circuit breaker can realize bidirectional breaking, and the breaking process of the forward breaking can be divided into four stages, as shown in Figures 4(a) to 4(d), and the current waveform diagram of the forward breaking process is shown in Figure 5.

[0098] Figure 4(a) is a normal current flowing stage of the circuit breaker, in which stage, the current flows in from the left end of the circuit breaker, passes through the fast vacuum switch and flows out from the right end. The pre-charging polarity of the transfer capacitor C is left negative and right positive.

[0099] Figure 4(b) illustrates the arc initiation and zero-crossing phases of the circuit breaker's operation. During this phase, the control system monitors the circuit current in real time. When a fault condition is detected and the short-circuit current drops to the first characteristic value, the control system sends a trip command to the fast vacuum switch, causing the moving and stationary contacts to separate and generate a vacuum arc. When the short-circuit current drops to the second characteristic value, the control system triggers thyristor T1, causing the transfer capacitor C and inductor to oscillate and generate a high-frequency transfer current. This transfer current is superimposed on the branch of the fast vacuum switch S1, causing the current flowing through the fast vacuum switch S1 to drop rapidly. Simultaneously, the transfer current flows through the transverse magnetic coil L1, applying a transverse magnetic field to the contact gap of the fast vacuum switch, accelerating the dissipation of the remaining plasma in the zero zone. When the current drops to the zero-crossing point, the fast vacuum switch successfully withstands the transient recovery voltage after the arc, and the short-circuit current begins to transfer to the current limiting module.

[0100] Figure 4(c) shows the current-limiting stage of the circuit breaker. In this stage, as the thyristor T1 cuts off at zero, all the short-circuit current is transferred to the current-limiting module. The current-limiting resistor has a relatively large resistance value, which can quickly dissipate fault energy and limit the short-circuit current to a low level.

[0101] Figure 4(d) shows the successful interruption stage of the circuit breaker. In this stage, the short-circuit current has been limited, and the control system sends a trip command to the auxiliary switch S2 to successfully interrupt the fault current.

[0102] The first and second characteristic values ​​during the current interruption process are determined by the control strategy. The basic principle for selecting the first characteristic value is to ensure that the moving and stationary contacts of the fast vacuum switch reach a certain opening distance when the current transfers to zero, so as to cooperate with the transverse magnetic field of the zero zone and ensure that it can withstand the transient recovery voltage after the arc. In actual circuit breaker operation, the setting of control parameters also needs to consider factors such as the mechanical delay of the operating mechanism. The basic principle for selecting the second characteristic value is that it needs to be less than the peak value of the transfer current. In order to ensure that the current of the fast vacuum switch S1 can reliably generate a zero-crossing point, a margin of 5kA to 10kA should be reserved. At the same time, considering that the relay protection action and the power electronic device action require time, the time from the second characteristic value to the minimum value of the fault current cannot be too short, so as to ensure that the zero-crossing point is generated before the minimum value of the fault current.

[0103] The circuit breaker can achieve bidirectional interruption. During reverse interruption, the fault current flows in from the right end of the circuit breaker, passes through the fast vacuum switch, and flows out from the left end. At this time, the pre-charge polarity of the transfer capacitor C is left negative and right positive. The transfer current generated after conduction cannot make the fast vacuum switch current cross zero. Therefore, it is necessary to trigger the thyristor T1 in advance to reverse the polarity of the transfer capacitor C to left positive and right negative. The subsequent control strategy and interruption principle are basically the same as those for forward interruption, and will not be elaborated here. A schematic diagram of the current waveform during reverse interruption is shown in Figure 6.

[0104] In another embodiment, the circuit breaker adopts a topology based on vacuum multi-break parallel connection, as shown in FIG. 7. The breaking capacity of a single vacuum break is far less than the short-circuit breaking requirement of a megawatt-level generator outlet, and the parallel connection of multiple vacuum breaks can effectively improve the breaking capacity of the circuit breaker. Each vacuum break is equipped with a transverse magnetic coil, and the transverse magnetic coils are connected in parallel. In order to improve the current sharing characteristics of the parallel breaks, the vacuum breaks and the transverse magnetic coils used in parallel need to use products of the same model and the same batch.

[0105] In this embodiment, the application method of the circuit breaker includes the following steps:

[0106] Step S100: When the fault current drops to a first characteristic value, send a breaking instruction to all vacuum switches of the vacuum multi-break parallel module S1 synchronously;

[0107] Step S200: When the fault current drops to a second characteristic value, trigger the thyristor assembly, and the transfer module releases a high-frequency transfer current to the vacuum multi-break parallel module S1, the current of each vacuum break branch drops rapidly, the direct current component decays, and an artificial zero point is created. At the same time, the transfer current flows through each transverse magnetic coil L1, and a transverse magnetic field is synchronously applied between the contact gaps of each vacuum break, accelerating the dissipation of zero-zone residual plasma and enhancing the dielectric recovery capability after the vacuum break arc;

[0108] Step S300: The vacuum multi-break parallel module S1 breaks over zero, the thyristor assembly breaks over zero, the fault current is limited by the current limiting module, a breaking instruction is sent to the auxiliary switch S2, and the breaking of the fault current is completed.

[0109] The above describes the basic principles of the present application in conjunction with specific embodiments, but it should be noted that the advantages, advantages, effects, etc. mentioned in the present application are only examples and not limitations, and these advantages, advantages, effects, etc. cannot be considered as the must-have of each embodiment of the present application. In addition, the above specific details are only for the purpose of example and understanding, and are not limited to the above specific details to realize the present application.

[0110] The above description has been given for the purpose of illustration and description. Furthermore, this description is not intended to limit the embodiments of the present application to the forms disclosed herein. Although the above has discussed a plurality of example aspects and embodiments, those skilled in the art will recognize certain variations, modifications, changes, additions and sub-combinations.

Claims

1. A topology of a zero-zone transverse magnetic enhancement type high-current circuit breaker, characterized in that, It includes, Zero-zone transverse magnetic enhancement type vacuum switch module, which includes, A fast vacuum switch, comprising a stationary contact and a moving contact, wherein separation of the stationary and moving contacts generates plasma. A transverse magnetic coil is provided, which is located close to the stationary contact and the moving contact to generate a transverse magnetic field in the gap between the contacts to accelerate the dissipation of zero-zone plasma, and the transverse magnetic coil is used in series in the transfer module. A transfer module, which is connected in parallel with the fast vacuum switch via an auxiliary switch; The current limiting module is connected in parallel with the transfer module. The transfer module includes a transfer capacitor and a transfer inductor connected in series at one end of the transverse magnetic coil, and a thyristor assembly at the other end of the transverse magnetic coil. The thyristor assembly includes thyristors T1 and T2 connected in reverse parallel. When the fault current drops to a first characteristic value, a tripping command is sent to the fast vacuum switch. The first characteristic value ensures that the moving and stationary contacts of the fast vacuum switch reach a certain opening distance when the current transfers to zero, and works in conjunction with the transverse magnetic field of the zero region to withstand the transient recovery voltage after the arc. When the fault current drops to a second characteristic value, the thyristor assembly is triggered, and the transfer capacitor C and inductor oscillate to generate a high-frequency transfer current. The current of the fast vacuum switch drops rapidly, the DC component decays, and an artificial zero crossing is created. At the same time, the transfer current flows through the transverse magnetic coil, and a transverse magnetic field is applied synchronously in the contact gap of the fast vacuum switch to accelerate the dissipation of the remaining plasma in the zero region and enhance the dielectric recovery capability after the arc. The second characteristic value is less than the peak value of the transfer current.

2. The topology of the zero-zone transverse magnetic enhancement type high-current circuit breaker as described in claim 1, characterized in that, Both the stationary and moving contacts adopt a cup-shaped longitudinal magnetic structure.

3. The topology of the zero-zone transverse magnetic enhancement type high-current circuit breaker as described in claim 2, characterized in that, The stationary contact includes, Static conductive rod, The stationary contact cup is connected to the stationary conductive rod, and the stationary contact cup has a first inclined groove that is inclined in a predetermined direction. A stationary contact piece is disposed at one end of the stationary contact cup relative to the stationary conductive rod. Moving contacts include, Moving conductive rod The moving end contact cup is connected to the moving conductive rod, and the moving end contact cup has a second inclined groove that is inclined in the predetermined inclined direction. The moving end contact piece is disposed at one end of the moving end contact cup relative to the moving conductive rod. The moving end contact piece and the stationary end contact piece switch between contact and separation. When current flows through the stationary end contact cup, the vacuum arc and the moving end contact cup, a longitudinal magnetic field that diffuses the vacuum arc is generated in the gap between the stationary contact and the moving contact.

4. The topology of the zero-zone transverse magnetic enhancement type high-current circuit breaker as described in claim 1, characterized in that, The fast vacuum switch is driven by a fast operating mechanism, which includes an electromagnetic operating mechanism and a spring operating mechanism.

5. The topology of the zero-zone transverse magnetic enhancement type high-current circuit breaker as described in claim 1, characterized in that, The current limiting module includes any one or a combination of ceramic resistors, aluminum-cased resistors, and cement resistors.

6. The topology of the zero-zone transverse magnetic enhancement type high-current circuit breaker as described in claim 1, characterized in that, The auxiliary switch includes any one or a combination of vacuum switches, air switches, and power electronic switches.

7. A breaking method for a topology of a zero-zone transverse magnetic enhancement type high-current circuit breaker as described in any one of claims 1-6, characterized in that, It includes the following steps, Step S100: When the fault current drops to the first characteristic value, send a trip command to the fast vacuum switch; Step S200: When the fault current drops to the second characteristic value, the thyristor assembly is triggered, and the transfer module releases the transfer current to the fast vacuum switch. The current of the fast vacuum switch drops rapidly, the DC component decays, and an artificial zero crossing is created. At the same time, the transfer current flows through the transverse magnetic coil, and a transverse magnetic field is applied synchronously in the contact gap of the fast vacuum switch to accelerate the dissipation of the remaining plasma in the zero region and enhance the post-arc dielectric recovery capability. Step S300: The fast vacuum switch breaks at zero crossing, the thyristor assembly cuts off at zero crossing, the fault current is limited by the current limiting module, and a tripping command is sent to the auxiliary switch to complete the fault current interruption.

8. A computer storage medium, characterized in that, The storage medium includes computer instructions that, when run on a computer, cause the computer to perform the method as described in claim 7.

9. An electronic device, characterized in that, The electronic device includes: Memory, processor, and computer programs stored in memory and executable on the processor, wherein, When the processor executes the program, it implements the method as described in claim 7.

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