CN222440447U - A high voltage switch device, power converter and energy storage system - Google Patents

Abstract

The present application provides a high-voltage switch device, a power converter and an energy storage system. The high-voltage switch device includes at least two electrical interfaces, a switch mechanism, a housing, a first grid group, a second grid group and a third grid group. The switch mechanism is used to disconnect the electrical connection of the at least two electrical interfaces, the housing is used to fix the at least two electrical interfaces and to form at least one arc extinguishing chamber, each arc extinguishing chamber is used to accommodate the first grid group, the second grid group and the third grid group, the first grid group includes a plurality of first grids arranged at intervals along a first direction, the second grid group includes a plurality of second grids arranged at intervals along the first direction, the third grid group includes a plurality of third grids arranged at intervals along the first direction, the first grid group is arranged at intervals with the second grid group and the third grid group respectively along the first direction, the first grid group and the second grid group are arranged at intervals along the second direction, and the first direction is perpendicular to the second direction. In this way, the number of grids in the arc extinguishing chamber can be increased, thereby improving the arc extinguishing ability of the high-voltage switch device.

Description

High-voltage switching device, power converter and energy storage system

Technical Field

The application relates to the technical field of power distribution, in particular to a high-voltage switching device, a power converter and an energy storage system.

Background

A switching device is an electronic component for switching on or off current in one or more circuits, which generally plays a controlling and protecting role in an electric power system. If the voltage of the circuit where the switching device is positioned is not lower than 10-20V, the current is not lower than 80-100 mA, and when the switching device is disconnected, an arc is generated between contacts of the switching device. The generation of the electric arc prolongs the on-off time of the circuit on the one hand, and on the other hand, the safe operation of the power system is easily endangered due to the high temperature of the electric arc, so that casualties and great loss of property are caused. When the switching device is used in a high voltage circuit, the switching device is required to have the ability to cool and extinguish an arc to reduce the hazard caused by the arc. However, the existing high-voltage switching devices have poor cooling effect on the arc, and limit the wide application of the devices.

Disclosure of utility model

In a first aspect, the present application provides a high voltage switching device comprising at least two electrical interfaces, a switching mechanism, a housing, a first set of grid blades, a second set of grid blades, and a third set of grid blades. The switch mechanism is used for disconnecting at least two electrical interfaces, the shell is used for fixing at least two electrical interfaces and forming at least one arc extinguishing chamber, each arc extinguishing chamber is used for accommodating a first grid plate group, a second grid plate group and a third grid plate group, the first grid plate group comprises a plurality of first grid plates which are arranged at intervals along a first direction, the second grid plate group comprises a plurality of second grid plates which are arranged at intervals along the first direction, the third grid plate group comprises a plurality of third grid plates which are arranged at intervals along the first direction, the first grid plate group is respectively arranged with the second grid plate group and the third grid plate group at intervals along the first direction, the second grid plate group and the third grid plate group are arranged at intervals along the second direction, and the first direction is perpendicular to the second direction. That is, the first grid sheet group and the second grid sheet group are enclosed to form a containing space, and the containing space is used for containing the third grid sheet group, so that the number of the grid sheets can be increased in the limited space, and the arc extinguishing capability of the high-voltage switch device is further improved.

In one possible embodiment, the first set of grid plates is spaced from the second set of grid plates by a distance that is less than the distance by which the first set of grid plates is spaced from the third set of grid plates in the first direction. When the electric connection of at least two electric interfaces is disconnected and an electric arc is generated, the electric arc sequentially passes through the first grid sheet group, the second grid sheet group and the third grid sheet group, so that the cooling path of the electric arc is prolonged, and the arc extinguishing capability of the high-voltage switch device is improved.

In one possible embodiment, the second set of louvers is larger in size than the third set of louvers in the first direction, and the first set of louvers is larger in size than the sum of the second set of louvers and the third set of louvers in the second direction. That is, the first grid sheet group and the second grid sheet group are enclosed to form a containing space, and the containing space is used for containing the third grid sheet group, so that the number of the grid sheets can be increased in the limited space, and the arc extinguishing capability of the high-voltage switch device is further improved.

In one possible embodiment, the high voltage switching device includes a first striking plate, wherein an end of the first striking plate is arranged between the housing and the second grid set along the first direction, and a distance between the end of the first striking plate and the second grid set along the first direction is smaller than a distance between the second grid set and the third grid set along the second direction. So set up, the electric arc can be conducted to the one end of first striking piece after the second bars piece group, and can not be conducted to certain third bars piece in the third bars piece group, and then the cooling path of extension electric arc improves the arc extinguishing ability of high tension switchgear. The other end of the first arc striking piece is arranged between the first grid piece group and the third grid piece group along the first direction, and the distance between the other end of the first arc striking piece and the third grid piece group along the first direction is smaller than the distance between the second grid piece group and the third grid piece group along the second direction. So set up, after electric arc is conducted to the one end of first striking piece, electric arc can further get into third bars piece group through the other end of first striking piece, and then the cooling path of extension electric arc, the arc extinguishing ability of high tension switchgear of improvement.

In one possible embodiment, the distance between the other end of the first striking plate and the third grid plate group is smaller than the distance between the other end of the first striking plate and the first grid plate group along the first direction. That is, the third gate group is closer to the other end of the first striking plate than the first gate group in the first direction. By the arrangement, the electric arc can be smoothly guided from the second grid plate group to the third grid plate group, so that the cooling path of the electric arc is prolonged, and the arc extinguishing capability of the high-voltage switch device is improved.

In one possible implementation manner, one end of the first striking piece is connected with the other end of the first striking piece through a connecting piece, an insulating plate is arranged between the connecting piece and the third grid piece group along the second direction, the connecting piece, the third grid piece group and the insulating plate enclose at least one air passage, one end of the first striking piece and the shell enclose another air passage along the first direction, and one air passage is communicated with the outside of the arc extinguishing chamber through the other air passage. When the electric arc passes through the third grid sheet group, high-temperature gas can be generated in the arc extinguishing chamber, and the high-temperature gas can be better discharged to the outside of the arc extinguishing chamber through the arrangement of the air passage, so that the safety of the high-voltage switching device is improved.

In one possible embodiment, the high-voltage switching device includes a second striking plate, wherein one end of the second striking plate is arranged between the third grid set and the housing in the second direction, and the other end of the second striking plate is arranged between the third grid set and the housing in the first direction. Along the first direction, the distance between one end of the second arc striking piece and the first grid piece group is greater than the distance between the other end of the first arc striking piece and the first grid piece group. That is, along the first direction, the other end of the first striking plate is located between the first grid plate group and one end of the second striking plate. In particular, when the electrical connection of at least two electrical interfaces is broken and an arc is generated, the arc entering the arc chute is elongated due to the action of the electromotive force. Wherein, one end of the electric arc is attracted to the first grid sheet group, the other end of the electric arc is attracted by one end of the second arc striking sheet and is further guided to the third grid sheet group by the other end of the second arc striking sheet, and voltage differences exist at two ends of the electric arc. Based on this, when the electric arc is elongated, through setting up the other end of first striking piece between the one end of first bars piece group and second striking piece, can make the electric arc further be attracted to the other end of first striking piece, and then make there is the voltage difference respectively between the other end of first striking piece and one end of first bars piece group and second striking piece, and then make the electric arc pass through first bars piece group, second bars piece group and third bars piece group more smoothly, improved high-voltage switch device's arc extinguishing ability.

In one possible embodiment, the distance between one end of the second striking plate and the third grid plate set along the second direction is greater than the distance between the other end of the second striking plate and the third grid plate set along the first direction. So set up, after the electric arc is attracted by the one end of second striking piece, the electric arc can get into third bars piece group through the other end of second striking piece better, and then the cooling path of extension electric arc improves high tension switchgear's arc extinguishing ability.

In one possible embodiment, the high-voltage switching device comprises a current path for connecting at least two electrical connections, the current path comprising a weak section, and the switching mechanism being provided for breaking the weak section. The distance between the weak section and the first grating sheet group is smaller than the distance between the weak section and the second grating sheet group along the first direction, and the distance between the weak section and the third grating sheet group is smaller than the distance between the weak section and the second grating sheet group along the second direction. That is, when the weak section is broken, one end of the arc is preferentially attracted to the first grid set, and the other end of the arc is preferentially attracted to the third grid set. When the voltage difference between the voltage at one end of the arc and the voltage at the other end of the arc is large, the arc is divided into a plurality of segments along the path of the first grid set-the second grid set-the third grid set and finally extinguished. Therefore, the arrangement can enable the electric arc to smoothly enter the first grid sheet group, the second grid sheet group and the third grid sheet group, and further improve the arc extinguishing capability of the high-voltage switch device.

In a second aspect, the present application provides an energy storage system comprising a high voltage switching device according to any one of the first aspects and one or more battery packs connected to the high voltage switching device by means of a dc bus, the switching mechanism of the high voltage switching device disconnecting the electrical connection of at least two electrical interfaces when the current flowing through the high voltage switching device is greater than a current threshold. When one or more battery packs in the energy storage system have short circuit or overcurrent faults, the high-voltage switch device can timely cut off the short circuit current loop, so that the short circuit faults are prevented from spreading to the power converter or the load side connected with the battery packs, and the safety and the stability of the power supply system are ensured.

In a third aspect, the present application provides a power converter, including the high voltage switching device of any one of the first aspects, an inverter circuit, a dc input terminal, and an ac output terminal, where the dc input terminal is used to connect a photovoltaic module or an energy storage system, the ac output terminal is used to connect a load, the high voltage switching device is connected between the inverter circuit and the dc input terminal, or the high voltage switching device is connected between the inverter circuit and the ac output terminal, and when a current flowing through the high voltage switching device is greater than a current threshold, a switching mechanism of the high voltage switching device disconnects electrical connection of at least two electrical interfaces. When a short circuit or overcurrent fault occurs in the power converter, the short circuit current loop can be cut off timely, so that the short circuit fault is prevented from spreading to a battery pack or a load side connected with the power converter, and the safety and stability of a power supply system are ensured.

In general, the application obviously improves the number of the grids which can be accommodated in the arc-extinguishing chamber by carrying out special size design and space arrangement on the first grid plate group, the second grid plate group and the third grid plate group, thereby effectively improving the arc-extinguishing capability of the high-voltage switch device. In addition, the application effectively realizes the series connection of the second grid sheet group and the third grid sheet group through the design of the first striking sheet, so that the electric arc smoothly passes through the first grid sheet group, the second grid sheet group and the third grid sheet group, the cooling path of the electric arc is prolonged, and the arc extinguishing capability of the high-voltage switch device is improved. In addition, the application also provides the air passage based on the structure, thereby better discharging the high-temperature gas in the arc extinguishing chamber and improving the working stability and the safety of the high-voltage switch device.

Drawings

FIG. 1 is a networking schematic diagram of an optical storage scene;

FIG. 2 is a networking schematic of an energy storage system;

FIG. 3 is a schematic view of a high voltage switching device according to the present application;

Fig. 4 is an exploded view of a high voltage switching device according to the present application;

Fig. 5 is an explosion schematic diagram of an arc extinguishing gate group in the short-circuiting device provided by the application;

FIG. 6 is a cross-sectional view of the high voltage switching device according to the present application taken in the plane A-A' shown in FIG. 3;

FIG. 7 is a schematic structural view of an insulating plate according to the present application;

FIG. 8 is a schematic view of the flow path of an arc in the cross-sectional view of FIG. 6 provided by the present application;

FIG. 9 is a schematic view of the structure of the lower housing according to the present application;

FIG. 10 is a schematic diagram of the positional relationship between the opening and closing piston and the through-flow bank according to the present application;

fig. 11 is a schematic structural diagram of a through-flow bank according to the present application.

Detailed Description

Referring to fig. 1, fig. 1 is a schematic diagram of networking in an optical storage scenario. In one aspect, when the light is sufficient, the photovoltaic module converts solar energy to direct current through the photovoltaic effect and transmits the direct current to the power converter, which then converts the direct current from the photovoltaic module to alternating current and transmits the alternating current to the grid or load. On the other hand, when the light is insufficient, the energy storage battery may also output direct current to the power converter, which then converts the direct current from the energy storage battery into alternating current and transmits the alternating current to the grid or the load. In practical applications, the power converter may be either a photovoltaic inverter or an energy storage converter. Unlike photovoltaic inverters, energy storage converters can convert direct current from a photovoltaic module or energy storage battery to alternating current for use by a load, and can also convert alternating current from a power grid to direct current for charging an energy storage system.

Specifically, the power converter includes a Direct Current input (not shown in fig. 1), a maximum power point tracking (Maximum Power Point Tracking, MPPT) circuit, an inverter circuit (Direct Current/ALTERNATING CURRENT, DC/AC circuit), and an alternating Current output (not shown in fig. 1). The MPPT circuit is used for changing the output power of the photovoltaic module, and the inverter circuit is used for converting direct current into alternating current.

In recent years, as the rated power of the power converter increases, the power converter can be connected with more photovoltaic modules or energy storage systems, but when the photovoltaic modules or the energy storage batteries have short-circuit faults, larger short-circuit currents can spread to the power converter and cause damage to the power converter. In this regard, in the industry, a high-voltage switching device is typically connected in series between a dc input terminal of the power converter and the inverter circuit, and when a current flowing through the high-voltage switching device exceeds a current threshold, the high-voltage switching device rapidly cuts off a short-circuit loop, thereby avoiding damage to the power converter. Similarly, as the rated power of the power converter increases, when the power converter itself has a problem, a large short-circuit current may spread to a load connected thereto and cause damage to the load. In this regard, a high voltage switching device may be connected in series between the ac output of the power converter and the inverter circuit, and when the current through the high voltage switching device exceeds a current threshold, the high voltage switching device rapidly shuts off the short circuit, thereby avoiding damage to the load.

In addition, referring to fig. 2, the high voltage switching device may be applied to an energy storage system. Specifically, the energy storage system comprises a battery pack and a high-voltage switching device, which are connected through a direct-current bus. When the energy storage system discharges, the direct current output by the one or more battery packs firstly passes through the high-voltage switching device and then flows to the power converter, and the power converter further converts the direct current into alternating current and supplies power for the load. When the battery pack in the energy storage system has short-circuit fault, the current flowing through the high-voltage switching device is synchronously increased until the current flowing through the high-voltage switching device exceeds a current threshold value, and the high-voltage switching device rapidly cuts off a short-circuit loop, so that the short-circuit current is prevented from spreading to the power converter and damaging the power converter.

As can be seen from the above description, as the rated power of the power converter increases, it is important to provide a high-voltage switching device for the power converter or the energy storage system. When a short circuit or an overcurrent fault occurs, the voltage across the high-voltage switching device is high due to the large current flowing through the high-voltage switching device, and when the high-voltage switching device cuts off the short circuit, an arc generally occurs. The electric arc is a discharge phenomenon with concentrated energy, high temperature and strong brightness, and if the electric arc is not extinguished for a long time, the electric arc will cause burning or even explosion of related electric appliances, thus endangering the safety of an electric power system. In this regard, the present application provides a high voltage switching device that can quickly cut off a short circuit and cool an arc, as will be described with particular reference to fig. 3-11.

First, the present application provides a high voltage switching device. Referring to fig. 3, fig. 3 is an external schematic view of a high-voltage switching device provided by the present application, and as shown in fig. 3, the high-voltage switching device includes a housing, a through-current bank 20, and two electrical interfaces 21. Wherein the housing includes an upper housing 10 and a lower housing 30 disposed opposite in a first direction (i.e., a direction in which the x-axis is located). The through-flow bank 20 is fixed between the upper case 10 and the lower case 30. The two electrical interfaces 21 are connected via a current bank 20 for connection to devices or circuits other than the high voltage switching devices. In addition, the lower case 30 is further provided with an opening 31, and the opening 31 is used for exhausting high-temperature gas in the high-voltage switching device. In practical application, in order to ensure the current capability, the materials of the current bank 20 and the electrical interface 21 may be copper, aluminum or copper-aluminum alloy, which is not limited in the present application. In addition, in practical applications, the upper case 10 and the lower case 30 may be integrally formed, or the upper case 10 may be omitted, which is not limited in the present application. In addition, in practical applications, the number of the electrical interfaces 21 may be set as required, and is not limited to two, but may be greater than two, which is not limited by the present application.

Referring to fig. 4, fig. 4 is an exploded schematic view of the high voltage switching device provided by the present application. As shown in fig. 4, the high voltage switching device further includes a switching mechanism including a power generator 52 and a breaking piston 51, wherein when the power generator 52 is not activated, the switching mechanism is accommodated in the upper case 10, and when the power generator 52 is activated, the power generator 52 pushes the breaking piston 51 to move to the lower case 30 along the first direction, and during the movement of the breaking piston 51, the breaking piston 51 cuts off the weak section 22 of the through-flow bank 20, thereby breaking the electrical connection of the two electrical interfaces 21. Due to the large voltage difference between the two electrical interfaces 21, an arc will be generated when the weak section 22 is opened, and in order to cool the arc in time, the high voltage switching device further comprises an arc chute 40, the arc chute 40 being accommodated in an arc chute formed by the lower housing 30. It should be noted that in fig. 4, the lower housing 30 forms two arc extinguishing chambers, each of which accommodates one arc extinguishing gate set 40, and in practical application, one or more arc extinguishing chambers may be provided as required, which is not limited in the present application. Specifically, the arc-extinguishing grating group 40 is located between the lower housing 30 and the through-flow row 20 along the first direction, when the weak section 22 is disconnected, the fracture corresponding to the weak section 22 will bend towards the arc-extinguishing grating group 40 and enable the arc to enter the arc-extinguishing grating group 40, and the plurality of grating sheets included in the arc-extinguishing grating group 40 can better cool the arc, so that damage of related equipment caused by the arc is avoided. In addition, since the arc generates a large amount of high temperature gas during the cooling process, the high temperature gas inside the high voltage switching device can be smoothly discharged by providing the opening 31 at the side surface of the lower case 30.

Referring to fig. 5, fig. 5 is an exploded schematic view of the arc chute assembly 40 provided by the present application. Specifically, the arc extinguishing gate group 40 includes a first gate group 41, a second gate group 42, and a third gate group 43. Wherein the first grid set 41 includes a plurality of first grid plates arranged at intervals along the first direction, the second grid set 42 includes a plurality of second grid plates arranged at intervals along the first direction, and the third grid set 43 includes a plurality of third grid plates arranged at intervals along the first direction. The first grid set 41 is arranged at intervals with the second grid set 42 and the third grid set 43 along the first direction, and the second grid set 42 is arranged at intervals with the third grid set 43 along the second direction (i.e. the y-axis direction), wherein the first direction is perpendicular to the second direction. Further, the size of the second grating group 42 is larger than the size of the third grating group 43 along the first direction, and the size of the first grating group 41 is larger than the sum of the sizes of the second grating group 42 and the third grating group 43 along the second direction. That is, the first and second louver groups 41 and 42 can enclose an accommodating space for accommodating the third louver group 43. By the arrangement, the number of the grid plates in the arc extinguishing chamber can be increased, and then the arc extinguishing capability of the high-voltage switch device is improved.

In order to better understand the special arrangement of the arc extinguishing gate group 40 and the beneficial effects thereof in this solution, the implementation principle of the gate arc extinguishing will be specifically described below. As described above, when the breaking piston 51 breaks the through-current bank 20 and generates an arc, the arc will enter the arc extinguishing gate group 40 by the electric force, and the arc will be cut into several pieces and finally extinguished since the arc extinguishing gate group 40 includes a plurality of gate pieces arranged at intervals. Specifically, when an arc enters the arc extinguishing grid set 40, each grid becomes an electrode, and there is a voltage drop between two adjacent grids, i.e., two adjacent grids may be equivalent to one battery. Accordingly, the arc chute group 40 may be equivalent to a battery cluster formed by connecting a plurality of batteries in series. When the total voltage drop that can be borne by the grid plates arranged at intervals is greater than the arc voltage of the electric arc, that is, when all the batteries in the battery cluster work and the voltage corresponding to the battery cluster is greater than the arc voltage of the electric arc, the electric arc is extinguished. It should be noted that, when the thickness of the grids in the arc-extinguishing grid set 40 and the interval between two adjacent grids are determined, the larger the number of the grids in the arc-extinguishing grid set 40 is, the larger the number of the batteries in the battery cluster is, and the stronger the arc-extinguishing capability of the arc-extinguishing grid set 40 is. In addition, although the size of the first gate group 41 along the second direction is larger than the sum of the sizes of the second gate group 42 and the third gate group 43, in terms of arc extinguishing ability, if the distance between two adjacent first gate sheets in the first gate group 41 along the first direction is equal to the distance between two adjacent second gate sheets in the second gate group 42 along the first direction, the pressure drop between two adjacent first gate sheets in the first gate group 41 is approximately equal to the pressure drop between two adjacent second gate sheets in the second gate group 42. Based on this, it can be understood that the present application significantly improves the number of the gate sheets receivable in the arc extinguishing chamber by performing a specific size design and spatial arrangement of the first gate sheet group 41, the second gate sheet group 42, and the third gate sheet group 43, thereby effectively improving the arc extinguishing capability of the arc extinguishing gate group 40.

With continued reference to fig. 5, one end of the first grating group 41 is aligned with one end of the second grating group 42 away from the third grating group 43 along the second direction, the other end of the first grating group 41 is aligned with one end of the third grating group 43 away from the second grating group 42 along the second direction, one end of the first grating group 41 is aligned with one end of the second grating group 42 and one end of the third grating group 43 along the third direction (i.e., the direction in which the z-axis is located), and the other end of the first grating group 41 is aligned with the other end of the second grating group 42 and the other end of the third grating group 43 along the third direction. The third direction is perpendicular to the first direction and the second direction. By the arrangement, the volume of the arc extinguishing chamber can be reduced, and the volume density of the high-voltage switch device is remarkably improved.

With continued reference to fig. 5, the arc extinguishing grid set 40 further includes a fixing plate 44, where the fixing plate 44 is made of an insulating material and is used for fixing the first grid set 41, the second grid set 42, and the third grid set 43. Specifically, the fixing plate 44 includes a plurality of hollow areas disposed at intervals, the first grid plate group 41, the second grid plate group 42 and the third grid plate group 43 include grid plates that are respectively provided with protrusions extending along the third direction, and the hollow areas are clamped with the protrusions, so that fixing is achieved. Further, the arc extinguishing grid set 40 further includes a filter grid 45, and the filter grid 45 is disposed opposite to the opening 31 of the lower case 30. Through setting up filtering grid piece 45, when the high temperature gas that high tension switchgear inner chamber produced mix with the particulate matter in, filtering grid piece 45 can filter these particulate matters effectively, and then improves the security of high tension switchgear.

Referring to fig. 6, fig. 6 is a cross-sectional view of the high voltage switching device taken in cross-section along the A-A' plane shown in fig. 3. As shown in fig. 6, the high voltage switching device further includes a first striking plate 46. Wherein, one end 461 of the first striking plate is arranged between the lower case 30 and the second grid set 42 along the first direction, and the distance between one end 461 of the first striking plate and the second grid set 42 along the first direction is smaller than the distance between the second grid set 42 and the third grid set 43 along the second direction. So configured, after the arc passes through the second grid set 42, the arc is conducted to one end 461 of the first striking plate, but not to a certain third grid in the third grid set 43, so as to prolong the cooling path of the arc and improve the arc extinguishing capability of the high-voltage switching device. Further, the other end 462 of the first striking plate is arranged between the first grid plate group 41 and the third grid plate group 43 along the first direction, and the distance between the other end 462 of the first striking plate and the third grid plate group 43 along the first direction is smaller than the distance between the second grid plate group 42 and the third grid plate group 43 along the second direction. So configured, after the arc is conducted to one end 461 of the first striking plate, the arc enters the third grid set 43 through the other end 462 of the first striking plate, thereby extending the cooling path of the arc and improving the arc extinguishing capability of the high-voltage switching device. Further, in the first direction, the distance between the other end 462 of the first striking plate and the third grid set 43 is smaller than the distance between the other end 462 of the first striking plate and the first grid set 41. That is, the other end 462 of the first striking plate is closer to the third gate group 43 than the first gate group 41 in the first direction. By this arrangement, the arc can be smoothly guided from the second grid group 42 to the third grid group 43, and the cooling path of the arc can be further extended, and the arc extinguishing ability of the high-voltage switching device can be improved. By providing the first striking plate 46, the arc of the second grid set 42 can be smoothly introduced into the third grid set 43.

With continued reference to fig. 6, the high voltage switching device further includes a second strike tab 47. One end 471 of the second striking plate is arranged between the third grid set 43 and the partition wall 32 along the second direction, and the other end 472 of the second striking plate is arranged between the lower housing 30 and the third grid set 43 along the first direction. It should be noted that the partition wall 32 is a part of the lower housing 30, and the partition wall 32 is used for dividing the lower housing 30 into two arc extinguishing chambers, each of which is used for accommodating one arc extinguishing gate set 40, and the two arc extinguishing gate sets 40 are symmetrical with respect to the partition wall 32. In addition, one end of the partition wall 32 is fixedly connected to the through-flow row 20 by a screw along the first direction, thereby fixing the through-flow row 20 better. When the high voltage switching device has only one arc extinguishing chamber, the partition wall 32 may be omitted, and at this time, one end 471 of the second striking plate is arranged between the third grid set 43 and the sidewall of the lower case 30 in the second direction. In addition, the distance between one end 471 of the second striking plate and the third grid set 43 along the second direction is greater than the distance between the other end 472 of the second striking plate and the third grid set 43 along the first direction. So set up, after the electric arc is attracted by the one end 471 of second striking piece, the electric arc can get into third bars piece group 43 through the other end 472 of second striking piece better, and then the cooling path of extension electric arc improves the extinction ability of high tension switchgear. In addition, the distance between one end 471 of the second striking plate and the first grid set 41 is greater than the distance between the other end 462 of the first striking plate and the first grid set 41 along the first direction. That is, the other end 462 of the first striking plate is located between the first grid set 41 and the one end 471 of the second striking plate in the first direction. So configured, the arc may be smoothly passed through the first, second and third sets of grids 41, 42 and 43, the specific principles of which will be described in detail below.

With continued reference to fig. 6, the high voltage switching device further includes a third striking tab 48. The third striking plate 48 is located between the through-flow row 20 and the first grid set 41 along the first direction, one end 481 of the third striking plate extends towards the through-flow row 20 along the first direction and contacts the through-flow row 20, and the other end 482 of the third striking plate extends along the second direction and is spaced from the first grid set 41. In addition, the distance between the end 481 of the third striking plate and the weak section 22 is smaller than the distance between the first grid set 41 and the weak section 22 along the second direction. That is, the third tab 48 is closer to the weak segment 22 than the first tab set 41, whether in the first or second direction. By means of the arrangement, when the weak section 22 of the through-flow row 20 is disconnected, the electric arc can be smoothly guided into the first grid plate group 41 by the third striking plate 48, so that the electric arc can completely pass through all the first grid plates included in the first grid plate group 41, and the arc extinguishing capability of the high-voltage switch device is improved. It should be noted that, in practical application, the end 481 of the third striking plate may be disposed near the through-flow row 20, that is, a gap may exist between the first bending portion 4212 and the through-flow row 20, which is not limited in the present application. In addition, the third striking plate 48 and a portion of the first grid plate near the through-current bank 20 are further connected to the through-current bank 20 by a fixing member such as a screw, so as to better fix the arc extinguishing grid set 40 in the arc extinguishing chamber.

With continued reference to fig. 6, one end 461 of the first striking plate is connected to the other end 462 of the first striking plate by a connecting piece 463, and an insulating plate 48 is further provided between the connecting piece 463 and the third grid set 43 along the second direction. To better illustrate the structure of the insulating plate 48, please continue to refer to fig. 7. As shown in fig. 7, the insulating plate 48 includes a first flat plate 482 and a second flat plate 483, wherein the first flat plate 482 is attached to a side of the connection piece 463 facing the third grid set 43, and the second flat plate 483 is attached to a side of the other end 462 of the first striking plate facing the third grid set 43. It should be noted that, to ensure that the second plate 483 is effectively attached to the other end 462 of the first striking plate, the first striking plate 46 further includes a third end 464, the third end 464 of the first striking plate extends toward the second grid set 41 along the second direction, and the third end 464 of the first striking plate is located between the other end 462 of the first striking plate and the third grid set 43 along the first direction. Further, the third end 464 of the first striking flake is connected with the other end 462 of the first striking flake and is arranged at intervals, and the third end 464 and the other end of the first striking flake are enclosed to form a narrow slit, and the second plate 483 is inserted into the narrow slit. It should be noted that, in practical application, the second plate 483 may also be directly attached to the other end 462 of the first arc striking plate through a fastener, a clamping member, or even an adhesive medium, so as to omit the third end 464 of the first arc striking plate. Further, a protruding portion 481 is further disposed on a surface of the first flat plate 482 facing the third grid set 43, and the protruding portion 481 is engaged with the third grid set 43, so as to achieve better fixation. On the basis, the insulating plate 48, the third grid group 43 and the connecting piece 463 are surrounded to form at least one air passage. Further, one end 461 of the first striking plate is spaced from the lower housing 30 along the first direction and encloses another air passage, and the other air passage is connected to the outside of the arc extinguishing chamber through the opening 31 of the lower housing 30. Further, the air passage is connected to the outside of the arc extinguishing chamber through another air passage, so that the high temperature gas generated in the arc extinguishing process of the third grid plate set 43 is discharged out of the arc extinguishing chamber.

With continued reference to fig. 6, one end 461 of the first striking flake, the other end 462 of the first striking flake, the other end 472 of the second striking flake, the other end 482 of the third striking flake, the third grid flake, and the second grid flake all extend along the second direction and are parallel to the first grid flake. By the arrangement, the volume of the arc extinguishing chamber can be reduced, and the volume density of the high-voltage switch device is remarkably improved.

In order to better explain the arc extinction principle of the high voltage switching device according to the present application, please refer to fig. 8, fig. 8 is a schematic diagram of the flow path of the arc in the cross-sectional view shown in fig. 6. As described above, when the current flowing through the through-flow bank 20 exceeds the current threshold, the power generator 52 pushes the breaking piston 51 to move toward the bottom of the cavity, the breaking piston 51 moves to break the weak section 22 of the through-flow bank 20, and an arc is generated between the breaks of the weak section 22. Taking the right-hand arc chute assembly 40 of fig. 8 as an example, when the electrical connection of at least two electrical interfaces 21 is broken and an arc is generated, the arc entering the arc chute is elongated due to the action of the electromotive force. Wherein, one end of the arc is attracted by one end 481 of the third striking plate and further guided to the first grid plate group 41 by the other end 482 of the third striking plate, the other end of the arc is attracted by one end 471 of the second striking plate and further guided to the third grid plate group 43 by the other end 472 of the second striking plate, and the voltage difference exists between the two ends of the arc. Further, when the arc is elongated, the other end 462 of the first striking plate is disposed between the first grid plate set 41 and the one end 471 of the second striking plate, so that the arc is further attracted to the other end 462 of the first striking plate, and further, a voltage difference exists between the other end 462 of the first striking plate and the other ends 472 of the first grid plate set 41 and the second striking plate, so that the arc can more smoothly pass through the first grid plate set 41, the second grid plate set 41 and the third grid plate set 43, and the arc extinguishing capability of the high-voltage switch device is improved. In practical applications, when the voltage difference between one end of the arc and the other end of the arc is large, if the other end 462 of the first striking plate is not disposed between the first grid set 41 and the one end 471 of the second striking plate, the arc may flow in the arc extinguishing grid set 40 in a chaotic manner, that is, the arc cannot be separated into multiple segments along the path of the third striking plate 48-the first grid set 41-the second grid set 42-the first striking plate 46-the third grid set 43-the second striking plate 47 and finally extinguished. Thus, the arc can smoothly enter the first, second and third gate groups 41, 42 and 43, thereby improving the arc extinguishing ability of the high voltage switching device.

It should be noted that the arc extinguishing gate set 40 provided by the present application can be applied to any scenario requiring high voltage arc extinguishing. However, in order to better demonstrate the working principle of the high-voltage switching device provided by the present application, the above figures show the through-flow row 20 for connecting two electrical interfaces 21, and the arc extinguishing principle of the high-voltage switching device is described in detail in connection with the flow path of the arc when the weak section 22 of the through-flow row 20 is disconnected. In practical application, the arc extinguishing gate group 40 can also be directly arranged between two switch contacts or between a moving contact and a fixed contact, so that arc extinguishing can be performed when the switch is opened or closed, and the safety and reliability of the high-voltage switch device are improved.

Referring to fig. 9, fig. 9 is a schematic structural view of a lower housing 30 according to the present application. As shown in fig. 9, the bottom of the lower case 30 is stepped, and the thickness of the stepped surface 33 near the opening 31 of the lower case 30 is smaller than the thickness of the stepped surface 33 far from the opening 31 of the lower case 30. Specifically, the step surface 33 adjacent to the opening 31 of the lower case 30 along the first direction is opposite to the one end 461 of the first striking plate and is disposed at an interval so as to enclose an air passage, and the air passage communicates with the outside through the opening 31 of the lower case 30. Further, a transition surface is further connected between the step surface 33 near the opening 31 of the lower case 30 and the step surface 34 far from the opening 31 of the lower case 30, and the transition surface is disposed obliquely to the first direction. In addition, the third grating group 43 is arranged on the step surface 34 far away from the opening 31 of the lower shell 30, so that the position of the third grating group 43 in the lower shell 30 is basically unchanged, and the structural stability of the high-voltage switch device is improved.

In order to better explain the process of cutting off the through-flow row 20 by the cut-off piston 51, refer to fig. 10, and fig. 10 is a schematic diagram of the positional relationship between the cut-off piston 51 and the through-flow row 20 provided by the present application. As shown in fig. 10, the breaking piston 51 has a cylindrical shape, and the through-flow line 20 has a flat strip shape, and the breaking piston 51 is disposed opposite to the weak section 22 of the through-flow line 20 along the first direction. The opening piston 51 includes four insulating arms 521 extending in the first direction, wherein adjacent two insulating arms 521 are oppositely disposed in the second direction or the third direction. It should be noted that an insulating wall 522 is further connected between two insulating arms 521 disposed opposite along the third direction, and the insulating wall 522 also extends along the first direction. Further, in a first direction, the weakened section 22 is disposed opposite the insulating wall 522. When the breaking piston 51 moves toward the bottom of the lower housing 30, the insulating wall 522 breaks the weakened section 22, thereby breaking the through-flow 20.

To better illustrate the process of breaking the through-flow via 20 by the insulating wall 522, referring to fig. 11, fig. 11 is a schematic view of the structure of the through-flow via 20 according to the present application. Specifically, the thickness of both the first end 201 of the through-flow row and the second end 202 of the through-flow row is d1 and the thickness of the weakened section 22 is d2, where d2< d1. When the breaking piston 51 breaks the weak section 22, the through-flow line 20 on the weak section 22 side is bent toward the arc extinguishing gate group 40 in the first direction. As described above, the weak portion 22 is disposed opposite to the insulating wall 522 of the breaking piston 51 in the first direction, and thus, when the breaking piston 51 moves toward the bottom of the inner cavity, the weak portion 22 can be cut off more smoothly, thereby improving the breaking speed of the through-flow bank 20.

In general, the present application significantly improves the number of the gate sheets receivable in the arc extinguishing chamber by performing a specific size design and spatial arrangement of the first gate sheet group 41, the second gate sheet group 42, and the third gate sheet group 43, thereby effectively improving the arc extinguishing capability of the high voltage switching device. In addition, the application effectively realizes the series connection of the second grid plate group 42 and the third grid plate group 43 through the design of the first striking plate 46, so that the electric arc smoothly passes through the first grid plate group 41, the second grid plate group 42 and the third grid plate group 43, thereby prolonging the cooling path of the electric arc and improving the arc extinguishing capability of the high-voltage switch device. In addition, the application also provides the air passage based on the structure, thereby better discharging the high-temperature gas in the arc extinguishing chamber and improving the working stability and the safety of the high-voltage switching device.

The application further provides an energy storage system, which comprises the high-voltage switching device and one or more battery packs, wherein the battery packs are connected with the high-voltage switching device through a direct-current bus, and when the current flowing through the high-voltage switching device is larger than a current threshold value, the switching mechanism of the high-voltage switching device breaks the electrical connection of at least two electrical interfaces. When one or more battery packs in the energy storage system have short circuit or overcurrent faults, the high-voltage switch device can timely cut off the short circuit current loop, so that the short circuit faults are prevented from spreading to the power converter or the load side connected with the battery packs, and the safety and the stability of the power supply system are ensured.

Further, the application provides a power converter, which comprises the high-voltage switching device, an inverter circuit, a direct current input end and an alternating current output end, wherein the direct current input end is used for being connected with a photovoltaic module or an energy storage system, the alternating current output end is used for being connected with a load, the high-voltage switching device is connected between the inverter circuit and the direct current input end, or the high-voltage switching device is connected between the inverter circuit and the alternating current output end, and when the current flowing through the high-voltage switching device is larger than a current threshold value, a switching mechanism of the high-voltage switching device breaks the electrical connection of at least two electrical interfaces. When a short circuit or overcurrent fault occurs in the power converter, the short circuit current loop can be cut off timely, so that the short circuit fault is prevented from spreading to a battery pack or a load side connected with the power converter, and the safety and stability of a power supply system are ensured.

The foregoing is merely illustrative of the present application, and the present application is not limited thereto, and any person skilled in the art will readily recognize that variations or substitutions are within the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims (11)

1. A high voltage switching device, comprising:

At least two electrical interfaces;

a switching mechanism for disconnecting the electrical connection of the at least two electrical interfaces;

The shell is used for fixing the at least two electric interfaces, the shell is used for forming at least one arc extinguishing chamber, each arc extinguishing chamber is used for accommodating a first grid plate group, a second grid plate group and a third grid plate group, the first grid plate group comprises a plurality of first grid plates which are arranged at intervals along a first direction, the second grid plate group comprises a plurality of second grid plates which are arranged at intervals along the first direction, the third grid plate group comprises a plurality of third grid plates which are arranged at intervals along the first direction, the first grid plates are respectively arranged with the second grid plate group and the third grid plate group at intervals along the first direction, the second grid plate group and the third grid plate group are arranged at intervals along a second direction, and the first direction is perpendicular to the second direction.

2. The high voltage switching device of claim 1, wherein the first set of gates is spaced from the second set of gates by a distance that is less than a distance by which the first set of gates is spaced from the third set of gates along the first direction.

3. The high-voltage switching device according to claim 1 or 2, wherein a size of the second gate group is larger than a size of the third gate group in the first direction, and a size of the first gate group is larger than a sum of the size of the second gate group and the size of the third gate group in the second direction.

4. The high voltage switching device of claim 1, wherein the high voltage switching device comprises a first strike plate, wherein:

One end of the first arc striking piece is arranged between the shell and the second grid piece group along the first direction, and the distance between the one end of the first arc striking piece and the second grid piece group along the first direction is smaller than the distance between the second grid piece group and the third grid piece group along the second direction;

The other end of the first arc striking piece is arranged between the first grid piece group and the third grid piece group along the first direction, and the distance between the other end of the first arc striking piece and the third grid piece group along the first direction is smaller than the distance between the second grid piece group and the third grid piece group along the second direction.

5. The high voltage switching device of claim 4, wherein a distance from the other end of the first striking plate to the third grid set is smaller than a distance from the other end of the first striking plate to the first grid set in the first direction.

6. The high voltage switching device according to claim 5, wherein one end of the first striking plate is connected to the other end of the first striking plate through a connecting plate, an insulating plate is included between the connecting plate and the third grid plate group along the second direction, at least one air passage is defined by the connecting plate, the third grid plate group and the insulating plate, one end of the first striking plate and the housing are defined by another air passage along the first direction, and the one air passage is communicated with the outside of the arc extinguishing chamber through the other air passage.

7. The high voltage switching device according to any of claims 4-6, wherein the high voltage switching device comprises a second striking tab, wherein:

One end of the second striking plate is arranged between the third grid plate group and the shell along the second direction;

The other end of the second striking plate is arranged between the third grid plate group and the shell along the first direction;

And the distance between one end of the second arc striking piece and the first grid piece group is larger than the distance between the other end of the first arc striking piece and the first grid piece group along the first direction.

8. The high voltage switching device of claim 7, wherein a distance between one end of the second striking plate and the third grid set along the second direction is greater than a distance between the other end of the second striking plate and the third grid set along the first direction.

9. The high voltage switching device of claim 1, comprising a through-flow bank for connecting the at least two electrical interfaces, the through-flow bank comprising a weakened section, the switching mechanism for breaking the weakened section;

The distance between the weak section and the first grid sheet group is smaller than the distance between the weak section and the second grid sheet group along the first direction;

And the distance between the weak section and the third grid sheet group is smaller than the distance between the weak section and the second grid sheet group along the second direction.

10. An energy storage system comprising a high voltage switching device according to any one of claims 1-9 and one or more battery packs connected to the high voltage switching device by means of a dc bus, the switching mechanism of the high voltage switching device disconnecting the electrical connection of the at least two electrical interfaces when the current flowing through the high voltage switching device is greater than a current threshold.

11. A power converter comprising a high voltage switching device according to any of claims 1-9, an inverter circuit, a dc input for connecting a photovoltaic module or an energy storage system, and an ac output for connecting a load, the high voltage switching device being connected between the inverter circuit and the dc input or the high voltage switching device being connected between the inverter circuit and the ac output, the switching mechanism of the high voltage switching device disconnecting the electrical connection of the at least two electrical interfaces when the current flowing through the high voltage switching device is greater than a current threshold.