Resistor structure and voltage divider device

Abstract

The invention relates to a resistor structure comprising at least one cylindrical electrically insulating substrate, at least one electrically conductive terminal arranged directly or indirectly on the substrate, at least one resistive path arranged directly or indirectly and at least partially on the substrate and connected directly or indirectly to the terminal, the resistive path extends at least partially along the cylindrical helix of the substrate and includes at least one resistive trace, where the geometry associated with the resistive path is configured such that the electric field intensity is at least partially reduced.

Description

Technical Field

[0001] The present invention relates to a resistor structure and a voltage divider arrangement and an electrical device comprising such a resistor structure and / or a voltage divider arrangement. Background Art

[0002] The resistor structure and the voltage divider arrangement are configured for high voltage applications, for example between 500 V and 1000 kV. Resistors used at high voltages have a high resistance (for example greater than 100 kΩ) to limit power dissipation.

[0003] The resistor structure may include an electrically insulating substrate, at least one electrically conductive terminal applied to the substrate, and at least one resistive track applied to the substrate and bonded to the terminal.

[0004] In its simplest embodiment, the voltage divider device may include two resistor structures electrically connected in series for converting a high voltage (so-called primary voltage) into a lower voltage (so-called secondary voltage). The secondary voltage is significantly less than the primary voltage, for example with a voltage division ratio of between 10 and 100,000. In more complex embodiments of the voltage divider, one or both of the series resistor structures may be replaced by a resistor network. The resistors or corresponding resistor networks may be referred to as high-ohm resistors and low-ohm resistors, respectively.

[0005] These devices can be integrated in electrical equipment in which particularly harsh operating conditions may occur, such as strong voltage overloads, power overloads, temperature changes, humidity changes, mechanical stress and shocks. Examples of electrical equipment are electronic instrument transformers (sensors), such as ABB's KEVCD and KEVA sensor types, which are typically used in power systems with rated primary voltages between 7.2 kV and 48 kV.

[0006] US 9,299,484 B2 discloses a resistor structure and a resistor voltage divider device, the contents of which are incorporated herein.

[0007] High voltage applications often require specific technical work to ensure functionality and safety. The reason is that such resistor structures are exposed to high electric field strengths, which often impose excessive electrical stress / static strength. This can lead to dielectric damage / insulation failures such as partial discharge or electrical breakdown.

[0008] Therefore, it is desirable to improve resistor structures and voltage divider arrangements with respect to manufacturing, reliability, and safety. Summary of the invention

[0009] The present invention is based on four aspects a to d, which can be implemented individually (independently of other aspects), in combination with one or more other aspects, or together, and can contribute to the technical solution individually and in combination.

[0010] The present invention relates to a resistor structure, comprising: at least one cylindrical electrically insulating substrate; at least one, preferably two, conductive terminals arranged directly or indirectly on the substrate; at least one resistive path arranged directly or indirectly on the substrate (optionally partially / segmentally) and directly or indirectly connected to the terminals, the resistive path extending at least partially along the cylindrical substrate in a spiral shape and comprising at least one / at least one resistive track, the resistive track having, for example, a resistive track tip (which may refer to the track end point and may be flat or rounded or pointed) and / or forming a plurality of spiral turns. The geometry associated with the resistive path is configured such that the electric field strength is at least partially reduced and / or such that:

[0011] (a) along at least a plurality of the resistive traces, optionally along any resistive trace of the resistive path, the slope of the resistive path relative to the circumferential direction does not exceed 15°, preferably 10°, more preferably 5°,

[0012] and / or

[0013] (b) at least one resistive trace, optionally more than one resistive trace, optionally at one end of the resistive path that is directly or indirectly joined to a terminal, has an effective length that is shorter than the actual length of the resistive trace,

[0014] and / or

[0015] (c) at one end of the resistive path, in the region where the resistive trace and the terminal join, the angle between the tip / end of the resistive trace and the terminal is less than 15°, preferably less than 10°, more preferably less than 5°,

[0016] and / or

[0017] (d) At one end of at least one resistive trace, the tip of the resistive trace is rounded.

[0018] Therefore, the present invention can help reduce the large differences in electric field strength caused by the geometry associated with at least a portion of the resistive path. Reducing the electric field strength can lead to a reduction in electrical stress. This helps avoid insulation failures such as partial discharge or electrical breakdown.

[0019] More specifically, at least some degree of equalization of the electric field strength can be achieved. In other words, the gradient of the electric potential can be reduced, so that a more uniform electric potential drop can be obtained. In particular, by means of a specific shape of the portion of the resistive path and / or of the entity connected to the resistive path, discontinuities due to the resistive path can be reduced or avoided, so that a more uniform electric field strength can be obtained. It is envisaged that along the resistive structure, the difference / variation of the electric field strength around the resistive path will not substantially exceed 50%, preferably not exceed 30%.

[0020] For example, a smoother transition between the terminal and the resistor path is achieved by controlling the effective resistor length through (multiple) shunt sections. Typically, there is a sudden change in geometry and resistivity between the terminal and the resistor path. If the shunt section adjusts the resistance near the end of the resistor path, the change in the effective resistor length can be considered as a resistance adjustment / modulation. That is, the "average value" of the resistance of the resistor path gradually increases from the terminal to the middle of the resistor path. This may be a more cost-effective (and more accurate) solution than using different materials with different resistivities.

[0021] By adjusting the geometry associated with the resistor path, the path itself, the connections within the path, or the connections at the end of the path can be configured accordingly. For example, a smoother extension of the resistor path can be obtained and / or a more seamless / smooth transition between the terminal and the resistor path can be supported. The abrupt termination of the resistor trace at its tip can be avoided.

[0022] The electric field strength is highest at the interface between the conductive / resistive entity and the insulator. This effect / strength is particularly severe at edges and sharp corners due to the accumulation of charge. The arrangement of terminals and resistor paths is improved to achieve a smooth / seamless distribution of the electric potential on and around the resistor structure (e.g. terminal-resistor path-terminal, terminal-insulator-terminal). There are local variations in the electric field strength near the edges of the terminals and resistor paths. A more "uniform distribution" should be understood as "uniform local variations" or that the peak value of the local variations is almost constant.

[0023] Therefore, by means of the present invention, the accuracy and voltage resistance of a resistor structure and a corresponding voltage divider arrangement can be improved.

[0024] The resistor materials commonly used in thick film technology are based on a formulation that mainly contains glass, conductive oxide ceramic particles (such as ruthenium oxide) and possibly other additives (such as metal particles). The resistivity (surface resistance / film resistance) of thick film resistor materials or multilayer films is usually between 50mΩ / square and 1GΩ / square.

[0025] In the context of the present invention, the resistive trace of the resistive path is made of a resistive material having a resistivity preferably between 50Ω / square and 100MΩ / square, or preferably between 500Ω / square and 10MΩ / square. Non-exhaustive examples of possible resistive materials are the R8700 series from Heraeus or the 2000 series from DuPont.

[0026] The conductive materials commonly used in thick film technology are based on formulations containing a large number of metal particles such as Ag, Pd, Au, Pt and possibly other additives. The resistivity of thick film conductor materials or multilayers is typically between 1 mΩ / square and 1 Ω / square. Non-exhaustive examples of possible conductive materials are C2210 from Heraeus or 7484 from DuPont.

[0027] The volume resistivity of the insulating material is greater than 10 7 Ω·cm.

[0028] Optionally, along the course of the resistance path, the slope of the resistance path relative to adjacent regions of the resistance path varies by less than 15°, preferably less than 5°. A uniform resistance path contributes to a uniform strength of the electric field.

[0029] Optionally, at least one of the resistor tracks or all of the resistor tracks included in the resistor path has an average slope along its entire length of less than 3°, preferably less than 2°. Such a slope can achieve greater uniformity along the path and allow a smoother connection to the terminal at the end of the resistor path. For example, the advantage can be that at the end of the resistor path, i.e. when in contact with the terminal, a suitable effective length of the resistor track can be achieved.

[0030] Optionally, the distance between mutually separated and consecutive regions of the resistor path, when viewed perpendicularly to the direction of the resistor path or in the direction of connecting the opposite terminals (i.e. in the longitudinal direction), can vary by less than 0.6 mm, or preferably by less than 0.2 mm, and optionally be substantially constant, wherein the regions belong to at least one resistor track. A uniform and smooth electric field strength can be supported if the distance between subsequent resistor tracks varies only slightly, almost without variation. If the resistor path has one or more tracks, the distance between the turns of the resistor path can vary by about 40% to 100% in the region of the transition element. The influence of these discontinuities on the peaks of the electric field strength can be negligible, especially when the ends of the resistor tracks are rounded.

[0031] Optionally, along substantially the entire resistive path, the distance varies by less than 50% or preferably by less than 20%, and is optionally substantially constant.If the distance varies only slightly or not at all along the entire resistive path, this may result in an effective improvement.

[0032] Optionally, the pitch of the helix varies by less than 50% or 20% and / or less than 1 mm or 0.2 mm, and is optionally substantially constant.It helps to avoid discontinuities if the pitch of the helical run of the resistive path along the cylindrical base is constant or has only slight deviations.

[0033] Alternatively, the pitch may be approximately equal to or greater than twice the distance between subsequent resistive traces.

[0034] Optionally, the radius of the end portion of at least one of the resistor traces is constant or decreases towards the tip of the resistor trace. If the resistor trace does not terminate abruptly, but terminates gradually with a rounded or curved terminal end, discontinuities along the resistor path can be avoided. If the curvature is defined by a constant radius or by a radius that decreases towards the tip of the resistor trace, a proper termination can be provided. The radius at the converging portion before the tip is substantially equal to or greater than 1 / 2 of the remaining full width of the resistor trace. Preferably, the radius near the base of the tip is greater than the radius at the tip.

[0035] Optionally, the terminal includes a shunt section that protrudes from the remaining terminal and is connected to a portion of the resistor trace away from the resistor trace end head. The shunt section can help adjust the effective length of the resistor trace, that is, shorten the actual length of the resistor trace by providing a connection to the resistor trace not at the resistor trace end head but before the resistor trace end head.

[0036] Optionally, the at least one shunt section represents an interconnection element connecting at least two resistive tracks in a direction perpendicular to the extension direction of the resistive path or from one end to the other of the structure, optionally also connected to the terminals. With respect to the effective length of the resistive tracks, the shunt section in the form of a connecting element can help to construct a voltage divider device.

[0037] Optionally, at least one resistor track at the end of the resistor path includes a connection portion that protrudes from the remaining resistor track along at least a portion of the length of the remaining resistor track in a direction perpendicular to the extension direction of the resistor path. Therefore, the connection portion can help adjust the effective length of the resistor track.

[0038] Optionally, the resistance path includes a plurality of resistance traces and a plurality of transition elements that interconnect the resistance traces in the direction of extension of the resistance path. The resistance path may include resistance traces that are electrically connected in series through transition elements to form the resistance path. The resistance traces may be at least partially parallel to each other. This allows efficient manufacturing. Alternatively, the resistance path may consist of a single resistance trace that extends continuously from one terminal to an opposite terminal. Continuous spiral turns may be considered as a single resistance trace without transition elements.

[0039] Optionally, at least one transition element represents an interconnection path of at least two resistor tracks connecting the resistor track along the extension direction of the resistor track and the terminal portion. This represents a parallel connection of the resistor tracks. In this way, the effective length of the resistor track can be adjusted.

[0040] Optionally, the resistor tracks are subsequently arranged along the course of the resistor path, wherein by connecting the at least two resistor tracks with a transition element that is longer than at least one of the plurality of transition elements, the effective length of at least two subsequent / subsequent resistor tracks is reduced. By adjusting the effective length of the resistor tracks, in particular at the end of the resistor path, with the length of the transition element used to connect the resistor tracks, a positive effect on the electric field can be achieved.

[0041] Optionally, at least the effective length of the subsequent resistive trace decreases towards the end of the resistive path, which is connected to the terminal. This contributes to the smoothness of the electric field near the terminal.

[0042] Optionally, the interconnection path connects at least one resistive track of the resistive path and a terminal, wherein a portion of the interconnection path connected to at least one resistive track of the resistive path is arranged substantially along the direction of the resistive track. This helps to reduce the electric field strength and stress at the end of the first resistive path and at the interconnection path.

[0043] The resistor structure of the present invention can be manufactured using thick film technology, such as screen printing or stencil printing or direct printing by nozzle. The conductive material film and the resistive material film are deposited sequentially on an insulating substrate. Typically, a single layer of a single material is deposited, followed by subsequent steps such as drying or firing. For example, the conductive film or the resistive film is fired at a very high temperature between 600°C and 950°C.

[0044] The insulating substrate may be made of a ceramic material, such as aluminum oxide or aluminum nitride.

[0045] In addition to the first conductive terminal, at least a second conductive terminal may typically be arranged in a resistive structure, wherein the resistive path connects the first terminal and the second terminal. In a voltage divider, a high ohmic resistor and a low ohmic resistor may share one terminal, so that the voltage divider arrangement may include at least a first terminal, a second terminal and a third terminal.

[0046] A covering / coating made of an electrically insulating material may be provided. In some embodiments, the covering may be the outermost entity or layer. The covering may cover the entire or a portion of the resistive structure. The covering may cover at least a portion of the resistive path and may cover a portion or portions of one or more terminals. A portion of each terminal is preferably not covered by the covering in order to provide an electrical connection to the resistive structure. The covering may be a film and may be made to a thickness between 5 and 100 μm and / or 3 and 30 μm. The covering may have different thicknesses, optionally with a first thickness between 5 and 100 μm and a second thickness between 3 and 30 μm, wherein the first thickness is at least 50% greater than the second thickness or at least 5 μm.

[0047] Optionally, a second coating material, for example made of a polymer, may be applied over the first coating material. The second coating material may be thicker than the first coating material.

[0048] A shunt may be provided. A shunt section is constructed to shunt different parts of a resistive trace to proportionally reduce its effective resistive length. This may mean that the electrically effective length (and therefore the resistance of the trace) is shorter than the actual length of the trace. A transition element may act as a shunt section. The resistivity of the shunt section is lower than the resistivity of the resistive trace to which the shunt section (e.g., transition element) is connected.

[0049] Optionally, the resistor structure comprises substantially identical resistor traces, and preferably arranged periodically with substantially the same pitch. The resistor traces may be made of the same resistor material, and may mostly have the same thickness, width, slope and (actual) length. This facilitates efficient and reproducible manufacture of the resistor traces and resistor paths.

[0050] Optionally, the resistive path comprises a plurality of spiral turns, and the resistance of the spiral turns decreases at an end portion of the path such that the resistance of a first spiral turn at the end portion of the resistive path is at least 15%, preferably at least 30%, less than the resistance of at least one of the plurality of spiral turns of the resistive path.

[0051] Optionally, a second helical turn of the resistive path has a resistance at least 10% less than a resistance of at least one of the plurality of helical turns of the resistive path, wherein the second helical turn preferably follows the first helical turn.

[0052] Optionally, at least one spiral turn of the resistance path is provided with one or more resistance traces and one or more transition elements and / or shunts having a resistivity less than the resistivity of the one or more resistance traces of the resistance path. That is, the spiral turn may include a plurality of transition elements connecting a plurality of resistance traces. Or the spiral turn may include a plurality of small shunts.

[0053] Optionally, two terminals are provided for the first resistive path, on opposite sides of the second resistive path. This may help reduce the electric field strength at the terminals.

[0054] The voltage divider device of the present invention may include a high-ohmic resistor and a low-ohmic resistor electrically connected in series, wherein the voltage divider device includes at least one resistor structure according to the present invention. The high-ohmic resistor is formed by one or more resistor tracks, the low-ohmic resistor is formed by one or more resistor tracks, and the resistances of the high-ohmic and low-ohmic resistors are different.

[0055] Optionally, the voltage divider arrangement is provided on the same substrate and comprises substantially identical resistive traces. This may provide a device that is more efficient to manufacture and more stable.

[0056] The electrical device of the present invention comprises the resistor structure or the voltage divider arrangement of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] Figure 1(a) to Figure 1(b) The resistor structure of the present invention is shown, wherein FIG. 1( a ) and FIG. 1( b ) show perspective views at different angles.

[0058] Figure 2(a) to Figure 2(c) The connection between the resistor trace and the transition element is schematically shown, where Figure 2(a) to Figure 2(c) Different embodiments are involved.

[0059] Figure 3(a) to Figure 3(b) The voltage divider device of the present invention is shown, wherein FIG. 3( a ) and FIG. 3( b ) show perspective views at different angles.

[0060] Figure 4(a) to Figure 4(b) Another voltage divider device of the present invention is shown, wherein FIGS. 4( a ) and 4 ( b ) show perspective views at different angles.

[0061] Figure 5(a) to Figure 5(b) The voltage divider device of the present invention is shown, wherein FIG. 5( a ) and FIG. 5( b ) show perspective views at different angles. DETAILED DESCRIPTION

[0062] Figures 1(a) and 1(b) show a resistor structure 1 of the present invention, wherein the structure 1 includes an electrically insulating substrate 2. The substrate 2 shown is a cylinder. At least one conductive terminal 4 is directly or indirectly disposed on the substrate 2. In the embodiment shown in Figures 1(a) and 1(b), two terminals 4 are provided, namely a first terminal 4-1 and a second terminal 4-2 at opposite (two) ends of the resistor structure 1. A resistance path 3 is directly or indirectly disposed on the substrate 2 and extends along a portion of the substrate 2. The resistance path 3 is directly or indirectly connected to the terminal 4. In the embodiment shown in Figures 1(a) and 1(b), the resistance path 3 is directly located on the substrate 2 and is directly connected to the first terminal 4-1 and the second terminal 4-2. The resistance path 3 extends spirally from the first terminal 4-1 to the opposite second terminal 4-2 along the cylinder formed by the substrate 2, and includes a plurality of resistance traces 8. The two resistance traces 8 are connected to each other by a transition element 7. The resistance path 3 is formed by at least a plurality of resistance traces 8 and a plurality of transition elements 7. Basically, the resistor tracks 8 are parallel to each other due to the spiral course of the resistor path 3. The resistor path 3 extends in a direction R, which is the extension direction of the resistor path 3, ie the spiral direction.

[0063] According to the present invention, the geometry associated with the resistor path 3 is configured so that the electric field strength is reduced at least locally along the structure 1. As shown in Figure 1(a), along any resistor trace 8 of the resistor path 3, the slope S of the resistor path 3 relative to the circumferential direction H (horizontal direction in Figures 1(a) and 1(b)) does not exceed 15°, preferably 10°, and more preferably 5°. The circumferential direction H extends perpendicular to the longitudinal direction L of the resistor structure 1 and contacts a point on the surface of the substrate 2. This supports a uniform intensity of the electric field between the end heads of the resistor structure 1. According to the embodiments of Figures 1(a) and 1(b), along the extension direction R of the resistor path 3, the slope S of the resistor path 3 relative to the adjacent areas of the resistor path 3 varies by less than 15°, preferably less than 5°. On the contrary, the slope S is substantially constant along the entire resistor path 3. The average slope Sm of the resistor trace 8 included in the resistor path 3 along its entire length is less than 3°. FIG. 1( a ) shows that the angle α between the end of the resistor track 8 and the terminal 4 is less than 15°, preferably less than 10°, and more preferably less than 5°.

[0064] FIG. 1( a) shows the distance D between the areas of the resistor trace 8 of the resistor path 3, which are spaced apart and consecutive from each other, when viewed from one end to the opposite end of the resistor structure 1. The distance D varies by less than 0.2 to 0.6 mm and is substantially constant in the embodiments of FIG. 1( a) and FIG. 1( b). The distance D should vary by less than 30% along the entire resistor path 3.

[0065] The helix formed by the resistive path 3 has a pitch P of about 0.3 to 3 mm and may vary by less than 50% to 20% and / or less than 0.2 to 1 mm. In the embodiment shown in Figures 1(a) and 1(b), the pitch P is constant.

[0066] FIG. 1( b ) shows the point t of the resistor track 8 1A , at this point t 1A Connect to terminal 4-2, where point t 1A denoted by a first active end of the resistor track 8 and an active end of the resistor path 3. The point at which the resistor track 8 connects to the transition element 7 is denoted by point t 1B The latter indicates the second effective end of the resistive track 8, so that the effective length l1 of the resistive track 8 is at point t 1A and t 1B The effective length l1 is shorter than the actual length of the resistor track 8 because the resistor track 8 also extends under the transition element 7 and under the second terminal 4-2 at the opposite end of the resistor track 8. Therefore, the effective length l1 of the resistor track 8 is shorter than its actual length. Where the resistor track 8 is connected to the first terminal 4-1, the effective length of the resistor track 8 at the opposite end of the path 3 is also effectively shortened.

[0067] FIG1(a) shows various transition elements 7, which have different lengths and positions relative to the resistive trace 8. More specifically, in the central portion of the resistive path 3, the effective length of the resistive trace 8 is longer, i.e., the trace 8 has an effective length l2 determined by the connection structure to the adjacent transition element 7, i.e., the effective length l2 along the extension line of the trace 8 from point t 2A To point t 2B . When observing the resistor traces 8 arranged sequentially along the resistor path 3, the effective length of at least two resistor traces 8 is reduced by connecting the two resistor traces 8 with a transition element 7 that is longer than the previous transition element 7. FIG. 1(a) shows that the effective length of the subsequent resistor trace 8 decreases from the middle of the resistor structure 1 to the end of the resistor path 3, which is connected to the terminal 4. In FIG. 1(a), four transition elements 7 having the same length approximately in the middle of the resistor path 3 are shown, wherein the length of the transition element 7 gradually increases toward the end of the resistor path 3, i.e., toward the terminal 4. Therefore, the effective length of the resistor trace 8 gradually shortens.

[0068] Figure 2(a) to Figure 2(c)The end of a resistor track 8 with a resistor track tip 9 is shown. A transition element 7 is connected to the resistor track 8. Typically, the resistor track tip 9 represents a 90° termination of the resistor track 8 relative to the extension of the resistor track 8 in the direction R, which can be seen as an abrupt termination of the resistor track 8. The present invention relates to a domed termination of the resistor track 8. This can be seen as a gradual decrease in the width of the resistor track 8 towards the tip 9. It can be seen that the end of the resistor track 8 has a certain curvature. In other words, the end of the resistor track 8 is rounded / rounded and has a radius r. In FIG. 2( a), the radius decreases towards the tip 9 of the resistor track. In FIG. 2( b), the tip 9 is rounded, wherein the end of the resistor track 8 has inclined surfaces (e.g. sides) converging towards the tip 9. In FIG. 2( c), the tip 9 is wider, wherein the radius r at the end of the resistor track 8 is larger. For example, in the embodiments of FIG. 1( a ) and FIG. 1( b ), the end portion of the resistor trace 8 is a rounded end.

[0069] 3(a) and 3(b) show a voltage divider device with a high-ohmic resistor 10 and a low-ohmic resistor 11. A first terminal 4-1, a second terminal 4-2 and a third terminal 4-3 are provided, wherein the first terminal 4-1 is arranged at an end of the structure 1 opposite to the end where the second terminal 4-2 and the third terminal 4-3 are located. Different transition elements 7 for connecting different resistive tracks 8 are provided. The end portions facing the second terminal 4-2 and the third terminal 4-3 are provided with a transition element 7 in the form of an interconnection path 13, and the transition element 7 is connected to the second terminal 4-2. Referring to FIG. 3(a), the interconnection path 13 connects at least two resistive tracks 8 (here four tracks 8) and the second terminal 4-2. As shown in FIG. 3(b), the structure 1 further includes: an interconnection element 12, which connects at least two resistive tracks 8 (or at least one resistive track 8), here three resistive tracks 8, in a direction perpendicular to the direction R; and a third terminal 4-3. There are two interconnection elements 12 connected to the terminal 4-3, but only one is visible. In other embodiments, three or more may be provided. The interconnection element 12 may be considered as a shunt section, which will be discussed in more detail below in conjunction with FIG. 5( a) and FIG. 5( b). However, the interconnection element 12 is not equivalent to the shunt in FIG. 5( a) and FIG. 5( b). The interconnection element 12 and the interconnection path achieve a parallel connection of the trace portions 8 to which they are connected.

[0070] 4(a) and 4(b) show a voltage divider device 5 similar to the device shown in FIG3(a) and 3(b). In addition, in the embodiment of FIG4(a) and FIG4(b), the resistor track at the end of the resistor path 3 at the terminal 4-1 includes a connecting portion 8a, which protrudes from the remaining resistor track 8 along at least a part of the length of the remaining resistor track 8 in a direction perpendicular to the extension direction R of the resistor path 3. In this way, when the position of the "first" contact between the resistor track 8 and the terminal 4-1 has been moved to the position t by the connecting portion 8a, 8a When the effective length of the resistor trace 8 at the terminal 4-1 is shortened, the connecting portion 8a can be regarded as reducing the effective length of the resistor trace 8.

[0071] Fig. 5 (a) and Fig. 5 (b) show a voltage divider device 5 similar to the device shown in Fig. 3 (a) and Fig. 3 (b). In addition, in the embodiment of Fig. 5 (a) and Fig. 5 (b), the terminals are specially constructed. More specifically, the terminal 4-1 includes a shunt section 4a, which protrudes from the remaining terminal 4-1 and is connected to a portion of the resistor trace 8 connected to the terminal 4-1, wherein the portion is away from the end of the resistor trace 8. For example, the shunt section 4a protrudes from the remaining terminal 4-1 in the direction relative to the terminals 4-2 and 4-3. The terminal 4-1 is provided with two shunt sections 4a, and the shunt path passes through the first shunt section 4a, the terminal 4-1 and the second shunt section 4a. The portion of the trace 8 located between the shunt sections 4a is shunted.

[0072] Reference numerals

[0073] 1 Resistor / resistor structure

[0074] 2 Electrically insulating substrate

[0075] 3 Resistor Path

[0076] 4 terminals

[0077] 4a Diversion section

[0078] 4-1 First terminal

[0079] 4-2 Second terminal

[0080] 4-3 The third terminal

[0081] 5 Voltage Divider Device

[0082] 7 Transition Elements

[0083] 8 Resistor traces

[0084] 8a Connection part

[0085] 9Resistor trace tip

[0086] 10 high ohm resistors

[0087] 11 Low Ohm Resistors

[0088] 12 Interconnection elements

[0089] 13 Interconnection Paths

[0090] S Slope of the resistance path

[0091] α Angle between the terminal and the resistor trace / resistor path

[0092] l Effective length of the trace

[0093] t A , t B The starting point and end point of the trace

[0094] H Horizontal direction / circumferential direction

[0095] L Longitudinal direction

[0096] R The direction of the resistance path

[0097] D Distance

[0098] P pitch of the helix

[0099] r Radius

Claims

1. A resistor structure (1), the resistor structure comprising at least: a cylindrical electrically insulating substrate (2), at least one conductive terminal (4) disposed directly or indirectly on the substrate (2), at least one resistive path (3), which is directly or indirectly and at least partially arranged on the substrate (2) and is directly or indirectly connected to the terminal, the resistive path (3) at least partially extending in a spiral along the cylindrical substrate and comprising a plurality of spiral turns and at least one resistive track (8), It is characterized in that The geometry associated with the resistive path (3) is configured such that the strength of the electric field is at least locally reduced, in particular such that: (a) along any resistive trace of the resistive path (3), the slope (S) of the resistive path (3) relative to the circumferential direction of the cylindrical substrate (2) does not exceed 15°, preferably 10°, more preferably 5°, and / or (b) optionally at least one resistive track (8) or optionally a plurality of resistive tracks (8) at one end of the resistive path (3) connected to the terminal (4) has an effective length that is shorter than the actual length of the resistive track (8), and / or (c) at one end of the resistor path (3), in the region where the resistor track (8) and the terminal (4) join, the angle (α) between the end of the resistor track and the terminal (4) is less than 15°, preferably less than 10°, more preferably less than 5°, and / or (d) A resistor trace tip (9) is provided at one end of at least one resistor trace (8), and the resistor trace tip (9) of the resistor trace (8) is rounded.

2. The resistor structure according to claim 1, wherein: According to (b), the resistance path (3) includes a plurality of spiral turns, and the resistance of the spiral turns located at the end portion of the resistance path (3) is reduced, so that the resistance of the first spiral turn located at the end portion of the resistance path is at least 15% smaller than the resistance of at least one of the plurality of spiral turns of the resistance path, and preferably at least 30% smaller.

3. The resistor structure according to claim 1 or 2, wherein: According to (a), the average slope (Stm) of at least one resistive track (8) or all resistive tracks (8) included in the resistive path (3) along their entire length is less than 3°, preferably less than 2°.

4. A resistor structure according to any one of the preceding claims, wherein: According to (a), when observed perpendicularly to the extension direction of the resistance path (3), the distance (D) between the areas of the resistance path (3) that are separated from each other and follow each other varies by less than 50%, preferably less than 20%, and / or is essentially constant, wherein the areas belong to at least one resistance track (8).

5. The resistor structure according to claim 4, wherein: According to (a) and (c), the distance (D) varies by less than 30% along substantially the entire resistive path (3), and is optionally substantially constant.

6. A resistor structure according to any one of the preceding claims, wherein: According to (b), the resistance of a second helical turn of the resistive path (3) is at least 10% lower than the resistance of at least one of the plurality of helical turns of the resistive path, wherein the second helical turn preferably follows the first helical turn.

7. A resistor structure according to any one of the preceding claims, wherein: According to (d), the radius (r) of the end portion of at least one resistive track (8) is constant or decreases towards the tip (9) of the resistive track (8).

8. A resistor structure according to any one of the preceding claims, wherein: According to (b), at least one spiral turn of the resistance path (3) is provided with one or more resistance tracks (8) and one or more transition elements and / or shunts, the resistivity of which is less than the resistivity of the resistance tracks (8) of the resistance path (3).

9. The resistor structure according to claim 8, wherein: At least one shunt section is an interconnection element (12) which connects at least two resistor tracks (8) in a direction perpendicular to the extension direction (R) of the resistor path (3), and is optionally also connected to a terminal (4-3).

10. A resistor structure according to any one of the preceding claims, wherein: The terminal (4-2) and the terminal (4-3) are arranged on opposite sides of the second resistance path relative to the first resistance path.

11. A resistor structure according to any one of the preceding claims, wherein: The resistance path comprises a plurality of resistance traces (8) and a plurality of transition elements (7) connecting the resistance traces (8) to each other in an extension direction (R) of the resistance path.

12. The resistor structure according to claim 11, wherein At least one transition element (7) is an interconnection path (13) which connects at least two resistive tracks (8) of the resistive path (3) and a portion of the terminal (4-2) along an extension direction (R) of the resistive path.

13. The resistor structure according to claim 11 or 12, wherein: According to (b), the resistor traces (8) are arranged continuously along the extension direction of the resistor path (3), wherein the effective length of at least one resistor trace (8) is reduced by connecting the at least two resistor traces (8) using a transition element (7), and the transition element (7) is at least 20% longer, or preferably at least 50% longer, and more preferably at least 100% longer than at least one of the multiple transition elements (7).

14. The resistor structure according to any one of the preceding claims 11 to 13, wherein: According to (b), the effective length of the subsequent resistor track (8) decreases towards the end portion of the resistor path (3) connected to the terminal (4).

15. A voltage divider device (5) for a power system for voltage conversion, the voltage divider device comprising a first resistor structure (1) and a second resistor structure (1), the first resistor structure being a resistor structure according to any one of the preceding claims, and the second resistor structure being a resistor structure according to any one of the preceding claims, wherein: The first resistor structure and the second resistor structure are connected in series, and the first resistor structure and the second resistor structure have different resistances.

16. An electrical device comprising a resistor structure (1) according to any one of claims 1 to 14 and / or a voltage divider arrangement (5) according to claim 15.

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