Hybrid voltage limiter including flip-flop electronics, thyristor components and varistors
By connecting the rheostat and thyristor components in parallel in a hybrid voltage limiter and using bypass to avoid spark gaps, the problem of dielectric breakdown under high current conditions is solved, and the operationality of the equipment is improved.
Patent Information
- Application Number
- CN202280098860.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2022-08-10
- Publication Date
- 2025-03-18
AI Technical Summary
Existing hybrid voltage limiters are prone to dielectric breakdown under high current conditions, resulting in instantaneous melting of bolts and electrodes.
A hybrid voltage limiter is designed, using a thyristor component connected in parallel with a varistor, and bypassing to avoid spark gaps, reducing the possibility of dielectric breakdown.
By reducing the resistivity in the current path and avoiding spark gaps, the risk of dielectric breakdown is significantly reduced and the operability of the voltage limiter is improved.
Smart Images
Figure CN119654689A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a hybrid voltage limiter, which comprises a first electrode, a second electrode, a trigger electronic device, a thyristor component and a varistor component, wherein the varistor component comprises a varistor and is connected in parallel with the thyristor component, wherein the thyristor component is electrically connected to the first electrode, the thyristor component is formed with two anti-parallel connected thyristors, the gates of the anti-parallel connected thyristors are connected to the trigger electronic device in a manner capable of receiving a trigger signal of the trigger electronic device, wherein the trigger electronic device is electrically connected to the first electrode and the second electrode, the thyristor component is electrically connected to the second electrode, the thyristor component is electrically connected to the second electrode, and the varistor component is electrically connected to the first electrode and the second electrode. Background Art
[0002] The hybrid voltage limiter comprises a parallel connection of a metal oxide varistor with two anti-parallel connected thyristors. The metal oxide varistor limits transient overvoltages caused by lightning and switching operations in the network. If an overvoltage occurs over a longer period of time (a few milliseconds to a few hours) due to a fault in the network or for operational reasons, the thyristor ignites and thus limits the transient voltage. As soon as a current zero crossing occurs, the thyristor extinguishes the current and restores the original state. As soon as the current is zero, the thyristor eliminates the current and restores the original state. Typically, the varistor circuit and the thyristor circuit are assembled one on top of the other, and they are insulated from the composite plate and connected to the electrodes by bolts. This means that all the current flowing through each parallel circuit then flows through each set of bolts. The problem is that when the current is too high, dielectric breakdown due to the small distance between the bolts and the electrodes may occur. Typically, this leads to instantaneous melting of the bolts and electrodes. Summary of the invention
[0003] It is therefore an object of the present invention to provide a hybrid voltage limiter which exhibits improved operability.
[0004] The object of the invention is solved by the subject matter of claim 1. Preferred embodiments are specified in the dependent claims.
[0005] The object is therefore solved by a hybrid voltage limiter comprising a first electrode, a second electrode, trigger electronics, a thyristor component and a varistor component, the varistor component comprising a varistor and connected in parallel with the thyristor component, wherein the thyristor component is electrically connected to the first electrode, the thyristor component is formed with two thyristors connected in anti-parallel, the gates of the anti-parallel thyristors being connected to the trigger electronics in such a way that they can receive a trigger signal of the trigger electronics, wherein the trigger electronics are electrically connected to the first electrode and to the second electrode, the thyristor component is electrically connected to the second electrode via a first resistivity, the thyristor component is electrically connected to the second electrode via a bypass having a second resistivity, the first resistivity having a higher resistance value than the second resistivity, and the bypass is connected to the second electrode in such a way as to avoid a spark gap, and the varistor component is electrically connected to the first electrode and to the second electrode.
[0006] Therefore, according to the invention, the second resistivity has a lower resistivity value than the first resistivity. This indirectly sets a path for most of the power to be collected by the thyristor component. The current preferably flows along the lowest resistance to the second electrode. Furthermore, by avoiding a spark gap between the bypass and the second electrode, the possibility of dielectric breakdown due to materials with a lower dielectric constant is avoided. A spark gap is a space between two conductive surfaces that can be overcome at a sufficiently high voltage so that a discharge can occur.
[0007] Generally, the bypass can be designed in different ways. However, according to a preferred embodiment of the invention, it is provided that the bypass has a first contact surface and a second contact surface, the second surface being located on a side opposite to the first contact surface, wherein an edge of the first contact surface is electrically connected to an edge of the second contact surface via a connection. This makes it possible to integrate the bypass into the hybrid voltage limiter without negatively affecting the design, while allowing high currents to flow.
[0008] According to a preferred embodiment of the invention, it is provided that the second contact surface of the bypass is circular and that the connection of the two contact surfaces has a width corresponding to the diameter of the second contact surface. The width of the connection, which corresponds to the diameter of the second contact surface, prevents the formation of edges and corners on the bypass and thus reduces the edges and corners and, thereby, the surface that will fit into the spark gap. The same applies to the circular shape of the second contact surface, which ensures a constant distance to the other conductor.
[0009] According to a preferred embodiment of the invention, it is provided that the bypass has a curved shape with a C-shaped cross section, and that the first contact surface corresponds to the lower part of said shape, the connecting part corresponds to the middle part, and the second contact surface corresponds to the upper part. This allows the varistor component to be accommodated in the open arc of the C-shape, thereby ensuring a compact and robust structure.
[0010] According to a preferred embodiment of the invention, it is provided that the thickness of the shunt is constant along its length.The constant thickness of the shunt ensures a constant resistance in the shunt and reduces the surface area that is otherwise susceptible to the spark gap.
[0011] The bypass can be made of different materials and material compositions as long as the resistivity of the material has a lower value than the first resistivity. However, according to a preferred embodiment of the invention, it is provided that the bypass consists of aluminum. Aluminum has a lower resistivity than the first resistivity and therefore allows better conduction of the current to the electrode, thereby preventing dielectric breakdown.
[0012] According to a preferred embodiment of the invention, it is provided that the shunt consists of copper. Copper has a lower resistivity than the first resistivity and thus allows better conduction of the current to the electrode, thereby preventing dielectric breakdown.
[0013] According to a preferred further development of the invention, it is provided that an angle of 90° is formed between the first contact surface and the connection portion, and an angle of 94° is formed between the second contact surface and the connection portion. Due to the slightly enlarged angle between the second contact surface and the connection portion, there is more space to accommodate the varistor board.
[0014] In principle, the hybrid voltage limiter can be designed in several ways. However, according to a preferred embodiment of the invention, it is provided that the first electrode is located on a side opposite to the second electrode, and the thyristor component is located between the first electrode and the second electrode, wherein the thyristor component is in electrical contact with the first electrode, wherein the thyristor component also includes a thyristor plate, which is arranged on a side facing the second electrode at the first contact surface of the bypass, and the insulating plate and the varistor component are arranged between the first contact surface and the second contact surface of the bypass, the varistor component also includes a varistor plate facing the insulating plate and the first contact surface, the varistor is arranged on a side of the second contact surface facing the first contact surface, the side of the second contact surface of the bypass facing the second electrode is arranged on the second electrode, the varistor plate is connected to the first electrode by an attachment, the thyristor plate is connected to the second electrode by an attachment, and the attachment has a first resistivity. Placing the individual components in this way ensures a compact design, which also minimizes the risk of dielectric breakdown at the contact point between the electrode and the circuit attachment of the thyristor.
[0015] In general, thyristor plates and varistor plates can be attached to the electrodes in different ways. However, according to a preferred embodiment of the invention, it is provided that the attachment is a screw and that the side of the second electrode facing the first electrode has a socket with an internal thread for receiving the screw, which sockets are applied to the surface of the second electrode so that the second electrode has no holes facing the first electrode. By not having any holes or interfaces interrupting the surface of the second electrode opposite to the first electrode, if the attachment is placed in the second electrode, no space is revealed for a spark gap that could cause dielectric breakdown.
[0016] According to a preferred embodiment of the present invention, it is provided that the first contact surface of the bypass has a triangular shape, wherein the first contact surface has a larger area than the second contact surface, and two corners of the triangle facing away from the connection portion each have a through hole.
[0017] The shunt can be inserted into the hybrid voltage limiter in various ways. However, according to a preferred embodiment of the invention, it is provided that the through-holes in the corners of the first contact surface of the shunt receive screws connecting the thyristor plate to the second electrode.
[0018] In principle, different varistor types can be used for the invention. However, according to a preferred embodiment of the invention, it is provided that the varistor is a metal oxide varistor. Metal oxide varistors exhibit an almost complete absence of current flow at a certain potential difference.
[0019] In general, the trigger electronics can be located at different positions. However, according to a preferred embodiment of the invention, it is provided that the first contact surface of the bypass has a centrally located through hole, and the insulating plate has a centrally located through hole, the varistor board recess is formed in the side of the varistor board facing the second electrode, the trigger electronics are arranged in the varistor board recess of the varistor board, the thyristor board through recess is formed in the thyristor board, and the trigger electronics are connected to the thyristor through the thyristor board by means of the thyristor board through recess. This allows the trigger electronics to be placed between the thyristor board and the varistor board.
[0020] The space between the electrodes can be filled with different materials. However, according to a preferred embodiment of the present invention, it is provided that the space formed between the first electrode and the second electrode is filled with silicone. Filling the space between the two electrodes with silicone improves the resistance of the component to external influences such as vibrations, temperature fluctuations and humidity changes.
[0021] According to a preferred embodiment of the present invention, it is provided that the space formed between the first electrode and the second electrode is filled with epoxy resin.
[0022] Further embodiments and advantages of the method derive directly and clearly from the system as described above to a person skilled in the art. BRIEF DESCRIPTION OF THE DRAWINGS
[0023] These and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter.
[0024] In the attached picture:
[0025] Figure 1 shows a schematic side view of a hybrid voltage limiter according to a preferred embodiment of the present invention;
[0026] Figure 2 A schematic cross-sectional view showing a hybrid voltage limiter according to a preferred embodiment of the present invention; and
[0027] Figure 3 A schematic diagram showing a bypass of a hybrid voltage limiter according to a preferred embodiment of the present invention is shown. DETAILED DESCRIPTION
[0028] Figure 1 A schematic side view of a hybrid voltage limiter 1 is shown. The hybrid voltage limiter 1 is cylindrical, and a first electrode 14 and a second electrode 15 form a boundary along the central axis of the cylindrical hybrid voltage limiter 1. The central axis of the hybrid voltage limiter 1 is perpendicular to the first electrode 14 and the second electrode 15. The individual electrodes are also cylindrical and have contact options on opposite sides facing away from each other, which are not shown in the drawings. The anti-parallel connected thyristors 5 are anchored in the first electrode 14 via pins, which are also not shown in the figure, and are conductively connected thereto. The thyristor plate 4 is placed on the thyristor 5, and similar to the first electrode 14, the thyristor plate 4 is also designed with holes for receiving pins from the thyristor 5. The thyristor 5 and the thyristor plate 4 form a thyristor component. The thyristor plate 4 is connected to the first electrode 14 via an insulating member 16, which surrounds the thyristor 5 on the outside of the thyristor 5. The thyristor plate 4 has holes for receiving screws 13, which connect the thyristor plate 4 to the second electrode 15. This connection is ensured by a socket 17 placed on the second electrode 15, which is correspondingly provided with an internal thread for receiving the screw 13, whereby no hole with an internal thread is required on the side of the second electrode 15 facing the first electrode 14 for fastening.
[0029] The bypass 6 is electrically connected to a first contact surface 18 resting on the thyristor plate 4. The first contact surface 18 of the bypass 6 has a through hole 24 for receiving a screw 13, so that the bypass 6 is also firmly connected to the thyristor plate 4. The insulating plate 3 is attached to the side of the first contact surface 18 of the bypass 6 facing the second electrode 15. The varistor board 2 is placed on the insulating plate 3, which also has a hole for receiving the screw 13. The screw 13 is therefore used to connect the varistor board 2 to the first electrode 14 via the internal thread socket 17 attached to the first electrode 14 in a similar manner to the thyristor plate 4 and the second electrode 15.
[0030] Figure 2 A cross-sectional view of a hybrid voltage limiter 1 is schematically shown. It can be seen here that the bypass 6 surrounds the varistor component consisting of a varistor 9 and a varistor plate 2. The bypass 6 also surrounds a contact washer 12, an insulating plate 3 and a gasket 8. The varistor component is electrically connected to a second contact surface 19 of the bypass 6 via the contact washer 12 and the gasket 8. The second contact surface 19 is in turn electrically connected to a second electrode 15. Both the varistor plate 2 and the thyristor plate 4 have an internal recess for accommodating the trigger electronics 10. The first contact surface 18 of the bypass 6 has a centrally located through hole 23. The insulating plate 3 also has a centrally arranged through hole. The trigger electronics 10 is electrically insulated from the varistor plate 2 via a mica disk 11. The trigger electronics 10 is connected to the gate and cathode of each thyristor 5 via a cable (not shown). The cable is fed through the centrally located thyristor plate through-recess 7 in the recess of the thyristor plate 4.
[0031] Finally, in Figure 3 , a bypass 6 of a hybrid voltage limiter 1 is shown. The bypass 6 has a C-shaped cross section, so that the insulating plate 3, the varistor plate 2, the contact washer 12, the varistor 9 and the second contact washer 12 and the gasket 8 are surrounded by a first contact area 18 and a second contact area 19. The first contact surface 18 and the second contact surface 19 are electrically connected via a connection 20. The first contact surface 18 and the connection 20 form an angle 21 of 90°. The second contact surface 19 and the connection 20 form an angle 22 of 94°. The first contact surface 18 of the bypass 6 has a substantially triangular shape. The corner facing the connection 20 is cut off. The two corners of the bypass 6 opposite to the connection 20 have through holes 24 for receiving screws 13. The second contact surface 19 of the bypass 6 is circular on the side facing away from the connection 20. On the side facing the connection 20, from the center of the circular second contact surface 19, there is a continuous connection to the connection 20, which has a width of the diameter of the second contact surface 19. This width is maintained over the entire connection 20 between the first contact surface 18 and the second contact surface 19 .
[0032] Starting from the first electrode 14, the current can flow via the thyristor 5 and the thyristor plate 4 to the first contact surface 18 of the bypass 6. At the same time, the current can flow from the first electrode 14 via the screw 13 to the varistor plate 2, the trigger electronics 10 and the varistor 9. Starting from the second electrode 15, the current can flow via the second contact surface 19 of the bypass 6 to the varistor 9, the varistor plate 2 and the trigger electronics 10. Likewise, the current can flow from the second electrode 15 via the screw 13 to the thyristor plate 4. However, at the same time, the current can flow from the second electrode 15 via the second contact surface 19, the connection 20 and the first contact surface 18 to the thyristor plate 4. Due to the lower resistivity of the aluminum bypass 6 and the flat contact at the thyristor plate 4 and the second electrode 15, the current will always prefer this flow direction over reaching the thyristor plate 4 via the screw 13.
[0033] Although the invention has been shown and described in detail in the drawings and the foregoing description, such illustration and description are to be considered illustrative or exemplary rather than restrictive; the invention is not limited to the disclosed embodiments. Other variations of the disclosed embodiments may be understood and effected by a person skilled in the art in practicing the claimed invention by studying the drawings, the present disclosure and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. Any reference signs in the claims should not be construed as limiting the scope.
[0034] Reference numerals list
[0035] 1 Hybrid Voltage Limiter
[0036] 2 Rheostat Board
[0037] 3 Insulation board
[0038] 4 Thyristor board
[0039] 5 Thyristor
[0040] 6 Bypass
[0041] 7 Thyristor plate through recess
[0042] 8 Gasket
[0043] 9. Rheostat
[0044] 10 Trigger electronics
[0045] 11 Mica disk
[0046] 12 Contact washer
[0047] 13 Screws
[0048] 14. First electrode
[0049] 15. Second electrode
[0050] 16 Insulation
[0051] 17 Socket
[0052] 18 First contact surface
[0053] 19 Second contact surface
[0054] 20 Connection
[0055] 21 90° Angle
[0056] 22 Angle of 94°
[0057] 23 Centrally positioned through hole
[0058] 24 Through Holes
Claims
1. A hybrid voltage limiter (1), comprising a first electrode (14), a second electrode (15), a trigger electronic device (10), a thyristor component and a varistor component, the varistor component comprising a varistor (9) and connected in parallel with the thyristor component, wherein: The thyristor component is electrically connected to the first electrode (14), The thyristor component is formed with two thyristors (5) connected in anti-parallel, The gate of the anti-parallel connected thyristor (5) is connected to the trigger electronic device (10) in such a way that it can receive a trigger signal of the trigger electronic device (10), wherein: The trigger electronics (10) is electrically connected to the first electrode (14) and the second electrode (15), The thyristor component is electrically connected to the second electrode (15) via a first resistivity, The thyristor component is electrically connected to the second electrode (15) via a shunt (6) having a second resistivity, The first resistivity has a higher resistance value than the second resistivity, and, The bypass (6) is connected to the second electrode (15) in a manner that avoids a spark gap, and The varistor component is electrically connected to the first electrode (14) and the second electrode (15).
2. The hybrid voltage limiter (1) according to claim 1, wherein: The bypass (6) has a first contact surface (18) and a second contact surface (19), the second contact surface being located on a side opposite to the first contact surface (18), wherein an edge of the first contact surface (18) is electrically connected to an edge of the second contact surface (19) via a connecting portion (20).
3. The hybrid voltage limiter (1) according to claim 2, wherein: The second contact surface (19) of the bypass (6) is circular, and the connecting portion (20) of the first contact surface and the second contact surface has a width corresponding to the diameter of the second contact surface (19).
4. The hybrid voltage limiter (1) according to claim 2 or 3, wherein: The bypass (6) has a curved shape having a C-shaped cross section, and the first contact surface (18) corresponds to a lower portion of the shape, the connecting portion (20) corresponds to a middle portion, and the second contact surface (19) corresponds to an upper portion.
5. The hybrid voltage limiter (1) according to any one of claims 2 to 4, wherein: An angle (21) of 90° is formed between the first contact surface (18) and the connecting portion (20), and an angle (22) of 94° is formed between the second contact surface (19) and the connecting portion (20).
6. The hybrid voltage limiter (1) according to any one of the preceding claims, wherein: The thickness of the bypass (6) is constant along its length.
7. The hybrid voltage limiter (1) according to any one of the preceding claims, wherein: The bypass (6) is made of aluminum.
8. The hybrid voltage limiter (1) according to any one of the preceding claims, wherein: The bypass (6) is made of copper.
9. The hybrid voltage limiter (1) according to any one of claims 2 to 8, wherein: The first electrode (14) is located on a side opposite to the second electrode (15), and The thyristor component is located between the first electrode (14) and the second electrode (15), wherein: The thyristor component is electrically connected to the first electrode (14), wherein: The thyristor component further comprises a thyristor plate (4) which is arranged on a side of the first contact surface (18) of the bypass (6) facing the second electrode (15), and The insulating plate (3) and the varistor component are arranged between the first contact surface and the second contact surface (19) of the bypass (6), The varistor component further comprises a varistor plate (2) facing the insulating plate (3) and the first contact surface (18), The varistor (9) is arranged on a side of the second contact surface (19) facing the first contact surface (18), The side of the second contact surface (19) of the bypass (6) facing the second electrode (15) is arranged on the second electrode (15), The varistor plate (2) is connected to the first electrode (14) by an attachment, The thyristor plate (4) is connected to the second electrode (15) by an attachment, and The attachment has the first resistivity.
10. The hybrid voltage limiter (1) according to claim 9, wherein: The attachment is a screw (13), and the side of the second electrode (15) facing the first electrode (14) has a socket (17) with an internal thread for receiving the screw (13), the socket being applied to the surface of the second electrode (15) so that the second electrode (15) has no hole facing the first electrode (14).
11. The hybrid voltage limiter (1) according to claim 10, wherein: The first contact surface (18) of the bypass (6) has a triangular shape, wherein the first contact surface (18) has a larger area than the second contact surface (19), and two corners of the triangular contact surface facing away from the connecting portion (20) each have a through hole (24).
12. The hybrid voltage limiter (1) according to claim 11, wherein: The through hole (24) in the corner of the first contact surface (18) of the bypass (6) receives the screw (13) connecting the thyristor plate (4) to the second electrode (15).
13. The hybrid voltage limiter (1) according to any one of the preceding claims, wherein: The varistor (9) is a metal oxide varistor.
14. The hybrid voltage limiter (1) according to any one of claims 2 to 13, wherein: The first contact surface (18) of the bypass (6) has a centrally located through hole (23), and the insulating plate (3) has a centrally located through hole, A varistor board (2) recess is formed in a side of the varistor board (2) facing the second electrode (15), The trigger electronics (10) is arranged in a recess of the varistor board (2) of the varistor board (2), A thyristor plate through-recess (7) is formed in the thyristor plate (4), and the trigger electronics (10) is connected to the thyristor (5) through the thyristor plate (4) by means of the thyristor plate through-recess (7).
15. The hybrid voltage limiter (1) according to any one of the preceding claims, wherein: A space formed between the first electrode (14) and the second electrode (15) is filled with silicone resin.