Sensor, protection circuit breaker, charging cable, and charging station

Abstract

To provide a sensor, a protection circuit breaker, a charging cable, and a charging station capable of achieving improvement or alternatives to the prior art.SOLUTION: The invention relates to a sensor (100) having, as a result of a passage in a shield (50) having a clear width of 25.2 to 32 mm, higher sensitivity for an electrical differential current, more particularly for universal-current sensitive determination of an electric differential current, over the prior art on the one hand and on the other hand a lower probability of a faulty detection of a differential current purportedly exceeding a limit current when a monitored circuit is switched on. The invention further relates to a circuit breaker, a charging cable and a charging station, each comprising a sensor of this kind.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a sensor, a protective circuit breaker, a charging cable, and a charging station. [Background technology]

[0002] Sensors for determining residual currents are known in various designs and for various applications, in particular since residual currents pose a danger to persons and can cause fires.

[0003] Residual currents occur when there is a fault in the power supply network, especially in a circuit within the power supply network, which allows fault currents to flow within the power supply network towards earth. Depending on the type and structure of the power supply network, the residual currents may have an AC component and / or a DC component.

[0004] The ever-increasing use of renewable energies, electromobility, variable speed electric machines and / or the like is resulting in an increasing number of electrical systems interconnecting AC and DC supply networks, which makes the DC component of the residual currents increasingly important.

[0005] Typically, especially in domestic electrical installations, only one fault current protective circuit breaker of type A is installed, which can monitor the domestic electrical grid for residual currents containing AC components, but cannot detect and interrupt DC faults. However, the use of DC elements in domestic electrical installations is increasing, for example when charging electric vehicles or operating solar systems.

[0006] There is therefore a need for a bi-current sensitive monitoring of the residual current, in particular during operation of a charging infrastructure or a solar inverter or the like, including a residual current sensor which shuts down the associated infrastructure if the detected measured value exceeds a limit value.

[0007] For the operation of charging infrastructure or solar inverters or the like, fault current circuit breakers of type B are known which are also able to detect and monitor the DC component of the residual current. However, fault current circuit breakers of type B are relatively expensive.

[0008] Dual-current-sensitive residual current sensors simultaneously monitor all currents flowing in the phase and neutral conductors and detect possible DC and AC faults. Depending on the application, the sensors can autonomously control the disconnection of the system in the event of an error or report the exceeding of a switching threshold to a higher-level control unit. Due to the very small permissible fault currents, excellent measurement accuracy is required. Furthermore, personal safety requires a particularly fast detection and subsequent shutdown of the entire system.

[0009] Known residual current sensors are based, for example, on a configuration in which a magnetic core is arranged with an air gap around the conductor to be monitored. If a current flows, a magnetic field is induced, which is guided by the magnetic core. In known configurations, a Hall element is arranged in the air gap, which generates an output voltage depending on the magnetic field strength. To increase the measurement accuracy, a compensation winding can be provided, which is attached to the magnetic core. This is achieved by electrically compensating for the magnetic field generated by the current to be monitored and adjusting the zero position of the Hall sensor. The actual output signal of such a sensor then represents the current required by the compensation winding.

[0010] Furthermore, it is known to use so-called flux-gate sensors to measure the magnetic field generated by the flow of electric current. In this method, a primary coil is wound on a magnetic core and driven with alternating current. An output signal, which depends on the residual current, is picked up by a secondary pick-up coil. Summary of the Invention [Problem to be solved by the invention]

[0011] The present invention is based on the problem of providing an improvement or alternative to the state of the art. [Means for solving the problem]

[0012] According to a first aspect of the invention, there is provided a sensor for determining a residual current, in particular for a bicurrent-sensitive determination of the residual current, comprising: the sensor comprises a magnetic field sensitive element, a first main winding, a test winding and a shield, The magnetic field sensitive element has a through opening, and the through opening of the magnetic field sensitive element is formed as an oval having a cross section with two axes of symmetry; a first main winding and a test winding, each having a plurality of windings, surrounding the magnetic field sensitive element; the shield has an accommodation space configured to accommodate the magnetic field sensitive element, the first main winding, and the test winding; the containment volume of the shield is radially defined by an outer shield wall and an inner shield wall; the inner wall of the shield defines a through-opening in the shield, the through-opening in the shield being formed as an oval having two axes of symmetry, the shielding body has a circumferentially extending gap in the region of the shielding body inner wall, a sensor configured to be disposed around at least two electrical conductors; the through-opening of the magnetically sensitive element has at least one inner width along the axis of symmetry, The problem is solved by a sensor in which the through opening of the magnetically sensitive element has at least one inner width along the axis of symmetry, the at least one inner width being in the range of 25.2 to 32 mm, preferably in the range of 25.5 to 29 mm, particularly preferably in the range of 25.8 to 27 mm.

[0013] In this regard, the following terminology is explained: Firstly, it is expressly pointed out that, if it is not clear from the respective context or if it is obvious or technically necessary for a person skilled in the art that there may be mentioned "exactly one...", "exactly two...", etc., within the scope of this patent application, indefinite articles and numerical descriptions such as "one", "two" etc. are generally to be understood as descriptions of "at least", i.e. "at least one...", "at least two...", etc.

[0014] Within the scope of this patent application, the expression "in particular" should always be understood as meaning that this expression introduces optional and preferred features. This expression should not be understood as "strictly" or "i.e."

[0015] A "sensor", or even a "detector", is a technological assembly capable of detecting certain physical or chemical properties and / or material properties in its surroundings "qualitatively" or quantitatively as "measurands". These quantities are detected by means of physical or chemical effects and converted into analog or digital electrical signals. Such signals are also called "sensor signals".

[0016] In particular, the sensor signal is proportional to the power consumption, in particular the power consumption of the test winding and / or the first main winding and / or the second main winding. In particular, the sensor signal, in particular the sensor signal of the test winding and / or the first main winding and / or the second main winding, can be converted into the power consumption using mathematical rules.

[0017] By "power dissipation" is understood the current intensity flowing through a circuit, in particular the test winding and / or the first main winding and / or the second main winding, at a defined voltage. It is explicitly pointed out that the term power dissipation does not require any information about the sign of the current. In particular, the power dissipation may correspond to a positive or negative current.

[0018] The sensor signal is preferably understood to mean the power consumption of the first main winding, which can in particular be converted into a residual current of one of the circuits monitored and specified by the sensor using a mathematical rule, which in particular can be determined by a calibration curve of the sensor.

[0019] By "residual current" is understood the vector sum of the currents of all the electrical conductors around which the sensor is arranged.

[0020] The residual current may have an AC component and / or a DC component.

[0021] By "dual-current sensitive determination" of the residual current, it is understood that the sensor is set in such a way that it can determine both the AC component and the DC component.

[0022] By "magnetic field sensitive element" is understood an element which reacts to a magnetic field by a change in at least one state quantity of the element.

[0023] In particular, a magnetic field sensitive element is understood to be a material having magnetic properties.

[0024] A magnetic field sensitive element is particularly preferably understood to be a soft magnetic material.

[0025] By "soft magnetic material" is meant a material which can be easily magnetized in a magnetic field. In particular, soft magnetic materials have a coercive force of less than 1,000 A / m.

[0026] By "coercivity" is understood the magnetic field strength required to completely demagnetize a magnetic field sensitive element before it is charged to its saturation magnetic flux density.

[0027] In particular, soft magnetic materials are understood to mean materials which are made from amorphous metals and have a nanocrystalline structure.

[0028] In particular, the soft magnetic material comprises an alloy containing iron, nickel and cobalt.

[0029] By "winding" is understood a turn of electrically conductive material in a solid aggregate, especially in the form of a wire, which extends around a magnetic field sensitive element.

[0030] By "main winding" is understood a winding that is configured to be actively supplied with current by a current source. Alternatively, the main winding can be connected to a voltage source. The main winding can also be called the "first main winding".

[0031] In particular, the main winding, in particular the first main winding, is configured to provide a sensor signal, in particular indirectly via the power consumption of the main winding, in particular indirectly via the power consumption of the first main winding and / or the second main winding.

[0032] In particular, from the power consumption of the main windings, in particular the first and / or second main windings, the residual current of a circuit that is specified and monitored by a sensor can be determined using mathematical rules, in particular using mathematical rules that can be derived from a calibration of the sensor.

[0033] By "test winding" is meant a winding which is set as a purely passive element so that a current flows as a result of the inductive effect arising from the magnetic field sensitive element. The test winding can in particular be set so as to provide a test winding signal which can be used within the scope of the calibration of the sensor. In particular, the test winding has in particular a different number of turns compared to the main winding.

[0034] In particular, the calibration of the sensor is carried out before the start of the actual measuring operation whenever a measuring operation is initiated.

[0035] By "shielding" is understood an element arranged to direct electric and / or magnetic fields away from a magnetic field sensitive element and / or to protect the surroundings of the sensor from the electric and / or magnetic fields emanating from the sensor.

[0036] In particular, the shield is made of an alloy containing at least 20% by weight of nickel, preferably at least 30% by weight of nickel, particularly preferably at least 50% by weight of nickel, more preferably at least 60% by weight of nickel, even more preferably at least 70% by weight of nickel, particularly preferably at least 80% by weight of nickel.

[0037] In particular, the shield is made of an alloy having at least 0.5% by weight of molybdenum, preferably at least 1% by weight of molybdenum, particularly preferably at least 3% by weight of molybdenum, more preferably at least 4% by weight of molybdenum, even more preferably at least 5% by weight of molybdenum, particularly preferably at least 5.5% by weight of molybdenum.

[0038] In particular, the shielding body is made of an alloy having at least 10% by weight of iron, preferably at least 20% by weight of iron, particularly preferably at least 30% by weight of iron, more preferably at least 40% by weight of iron, even more preferably at least 50% by weight of iron, particularly preferably at least 55% by weight of iron.

[0039] It is expressly pointed out that the above values ​​for the alloy composition of the shield should not be understood as definite limits, but rather should be able to be exceeded or exceeded on an engineering scale without departing from the described aspects of the invention. In simple terms, these values ​​should provide an indication of the magnitude of the alloy composition of the shield proposed herein.

[0040] In particular, the shield is of multi-part, in particular two-part, construction.

[0041] Particularly preferably, a two-part shield is formed in such a way that the two shield parts overlap or at least partially overlap one another at the shield outer wall.

[0042] Furthermore, it is particularly preferred that the two-part shield is formed in such a way that the two shield parts do not come into contact with each other on the inner wall of the shield, and the two shield parts of the two-part shield preferably form a gap on the inner wall of the shield.

[0043] By "through opening" is understood a free cross section which is formed in the inner region of the magnetic field sensitive element.

[0044] Particularly preferably, the outer contour of the magnetic field sensitive element is designed as an oval and the inner contour of the magnetic field sensitive element is also formed as an oval with two axes of symmetry.

[0045] The inner contour of the magnetic field sensitive element defines an aperture therethrough for the magnetic field sensitive element.

[0046] In particular, the material thickness of the magnetic field sensitive element is approximately constant or constant. In the special case where the magnetic field sensitive element is formed as a circle in cross section and the material thickness of the magnetic field sensitive element is constant, the magnetic field sensitive element has a cross-sectional geometric shape of a circular ring.

[0047] An "oval" is a flat, rounded, convex outline. Unlike the circle and the ellipse, which are special cases of ovals, an oval need not have an "axis of symmetry". In particular, an oval is a closed convex curve in the plane that is twice continuously differentiable.

[0048] If the curves of an oval are mirror-imaged on either side of an imaginary line, then the oval has an axis of symmetry. If the curves of an oval are mirror-imaged on either side of two non-coincident imaginary lines, then the oval has "two axes of symmetry." In particular, the circle and the ellipse are each ovals with two axes of symmetry.

[0049] By "winding" is understood the turn of a winding around the magnetic field sensitive element.

[0050] The "accommodation space" is defined by the shield within the shield and is configured to accommodate other elements, in particular the magnetic field sensitive element, the first main winding, and the test winding, as well as the second main winding, insulators, and spacer rings.

[0051] "Radial" is understood to mean a direction extending linearly from a central axis of the sensor that runs normal to the smallest possible cross-sectional area of ​​the through opening, radially relative to the central axis.

[0052] By "outer shield wall" is understood the radially outer surface formed by the shield, in particular by a two-part shield fitted together.

[0053] By "shielding inner wall" is meant the radially inner surface formed by the shielding body, in particular by a projection surface, with any possible partial surfaces of the shielding body located on the inside and a circumferentially extending gap.

[0054] By "circumferentially extending gap" is understood a gap extending in the circumferential direction in the inner wall of the shielding between the partial surfaces of the inner wall of the shielding formed by the shielding. A circumferentially extending gap opens the shielding in the direction of the receiving space of the shielding, as seen in the radial direction and from the central axis.

[0055] By "electrical conductor" is meant any medium that has mobile charge carriers and thus can transport electric charges. In particular, by electrical conductor is meant copper and / or aluminum cables as conductors through which electrons can move.

[0056] By "internal width" along the axis of symmetry of a through opening is understood the extension of the through opening in the direction and height of the observed axis of symmetry.

[0057] If the ellipse which in cross section forms the through opening of the magnetic field sensitive element has two axes of symmetry with different extensions along the axes of symmetry, a first inner width occurs along the first axis and a second inner width occurs along the second axis of symmetry.

[0058] If merely the inner width is mentioned in this document, this refers in particular to the inner width along the axis of symmetry having the greater extension.

[0059] By "limiting current" is understood a residual current which the sensor is able to detect with sufficient accuracy and sufficient speed so that the protective circuit breaker can interrupt the voltage in the circuit monitored by the sensor as soon as a residual current which at least reaches or exceeds the limiting current of the protective circuit breaker is detected by the sensor.

[0060] The smaller the limit current of the protective circuit breaker, and therefore directly also the measurement suitability of the slight residual current of the sensor, and the faster this can be reliably recognized by the sensor, the less danger can result from residual currents occurring.

[0061] Sensors are known in the prior art that have smaller internal widths of the through apertures of the magnetic field sensitive elements than those proposed here.

[0062] In particular, prior art efforts have been made to reduce the interior width of the through apertures of magnetic field sensitive elements.

[0063] The motivation for this effort is that the desire to make residual currents smaller and more quickly detectable necessitates placing magnetic field sensitive elements as close as possible to the live electrical conductors of the monitored circuit.

[0064] The strength of the magnetic field emanating from a current-carrying electrical conductor falls off inversely with the distance from the current-carrying electrical conductor, so the further away a magnetic field sensitive element is from the current-carrying electrical conductor of the monitored circuit, the lower the magnetic flux density in the magnetic field sensitive element caused by the magnetic field strength around the current-carrying electrical conductor.

[0065] In addition to this, the magnetic field strengths of at least two current-carrying electrical conductors of the monitored circuit, both of which must be passed through the through opening of the magnetic field sensitive element in order to monitor the residual current and which have opposite current flow directions, superpose and, in an idealized case, cancel each other out, as long as no residual current occurs in the monitored current circuit.

[0066] As a result, the magnetic field strength acting on the magnetic field-sensitive element is particularly low, in particular when the residual currents in the monitored circuit are small, which results in a particularly low magnetic flux density at the magnetic field-sensitive element.

[0067] The lower the magnetic flux density in the magnetic field sensitive element, the lower the current it will induce in the test winding and / or the first main winding and / or the second main winding.

[0068] In other words, the larger the inner width of the through opening of the magnetic field sensitive element, the greater the distance of the electrical conductor of the monitored circuit from the magnetic field sensitive element can be, so that small residual currents cannot be detected at all or can only be detected with particular difficulty.

[0069] For this reason, the requirement to be able to detect relatively small residual currents leads to technical efforts to make the inner width of the through opening of the magnetic field sensitive element as small as possible.

[0070] Making the magnetic field sensitive element as small as possible also leads to a lighter sensor, requiring less material and therefore less cost and space.

[0071] Thus, many factors favor a smaller inner width for the through aperture of the magnetic field sensitive element.

[0072] It is known in the art that protective circuit breakers that have very small residual currents tend to malfunction when the circuit they monitor is turned on.

[0073] The reason is that when a circuit is switched on, sensors known from the prior art generate a sensor signal that can be interpreted as a residual current, even though there should be no residual current in the monitored circuit. The requirement for smaller residual currents means an increased number of false trips of protective circuit breakers.

[0074] However, contrary to conventional knowledge, it has been discovered quite unexpectedly in laboratory experiments that there is an optimal range of the inner width of the through opening of the magnetic field sensitive element in which the smallest possible residual current can be detected within a sufficient time and at the same time the possibility of false operation of the protective circuit breaker connected to the sensor can be significantly reduced, and that the range discovered requires an inner width of the through opening of the magnetic field sensitive element that is larger than previously known in the prior art.

[0075] In other words, a range of inner widths of the through opening has been found that allows for a robust determination of the smallest possible residual current, so that when the circuit monitored by the sensor is turned on, no sensor signals exceeding the required limit current, which can be interpreted as a residual current, or which occur only very rarely.

[0076] In order to achieve a minimum limiting current in the monitored circuit that can be robustly determined by the sensor, it is proposed that the inner width of the through opening of the magnetic field sensitive element is in the range of 25.2 to 32 mm.

[0077] Preferably, it is proposed that the inner width of the through opening of the magnetic field sensitive element is in the range of 25.5 mm to 29 mm.

[0078] Particularly preferably, it is proposed that the inner width of the through opening of the magnetic field sensitive element is in the range of 25.8 mm to 27 mm.

[0079] It is clearly pointed out that the above values ​​of the inner width of the through opening of the magnetic field sensitive element should not be understood as definite limits, but rather should be able to be exceeded or exceeded on an engineering scale without departing from the described aspects of the present invention. In short, these values ​​should provide an indication of the size of the inner width of the through opening of the magnetic field sensitive element proposed herein.

[0080] Of course, any combination of the recited range limits for the inner widths may be used.

[0081] When a voltage supply is switched on in a monitored circuit, a physical operative connection is established between the magnetic field prevailing around an electrical conductor and the magnetic flux density in operative relationship therewith.

[0082] This results in a brief, time-varying pulse of magnetic flux that is primarily location-dependent in the magnetic field sensitive element when turned on.

[0083] This primarily results in oscillatory behavior of the magnetic flux in the magnetic field sensitive element.

[0084] This brief oscillatory behavior in the magnetic field sensitive element also briefly results in a bypassed current flow in the test winding and / or the first main winding and / or the second main winding, which are in operative relationship with the magnetic field sensitive element via induction.

[0085] Laboratory experiments have shown that this can briefly result in a sensor signal that can be interpreted as a residual current, which can cause a predefined limit current to be exceeded during the specified operation of the sensor in the protective circuit breaker, which can cause a shutdown of the protective circuit breaker when the voltage supply of the monitored circuit is switched on.

[0086] Several different factors affect the damping of this short-term vibration behavior, some of which cannot be influenced by design measures.

[0087] In laboratory experiments, it has been found that one of these factors is determined by the spacing between the electrical conductors to be monitored by the proposed sensor: the greater the distance or spacing, the stronger the dynamic interaction between the electrical conductors and the sensor signal when the voltage supply source is switched on.

[0088] Safety concerns regarding the spacing of electrical conductors in the cross section of the through opening of the magnetic field sensitive element require ever greater spacing to avoid short circuits between the electrical conductors, which amplifies this factor and increases the tendency for undesired sensor signals to occur when the circuit is turned on.

[0089] Another factor, also confirmed in laboratory experiments, has to do with the ratio of the distance between the first and the different electrical conductors to a point on the magnetic field sensitive element. The further away from the said ratio is from the number 1, the greater the short-term regional differences in the magnetic flux density on the magnetic field sensitive element. The greater these regional differences are, the stronger the amplification of the dynamic starting behavior of the sensor when the circuit is switched on.

[0090] By increasing the inner width of the through opening of the magnetic sensitive element, the ratio of the distance between the first electrical conductor and the different electrical conductor to a point in the magnetic field sensitive element can be brought closer to the value 1, thereby advantageously achieving a damping effect of the sensor behavior due to the above-mentioned switch-on effect.

[0091] Since an increase in the inner width of the magnetic field sensitive element leads to a decrease in sensitivity, especially to small residual currents, an optimal range of the inner width of the through opening of the magnetic field sensitive element is proposed in which two physical effects are taken into account, so that, on the one hand, the minimum residual current in normal operation of the sensor can be detected within a sufficient time, and, on the other hand, when the power grid monitored by the sensor is turned on, no sensor signal is generated that conveys a false detection of a non-existent residual current.

[0092] In particular, it is proposed here to configure the sensor in such a way that it can be placed around all conductors of the circuit which during normal operation introduce and extract currents to the monitored circuit, and in particular not around protective conductors.

[0093] In particular, it is proposed to arrange the proposed sensor around the outer conductor and the neutral conductor in the specified use in a single-phase power supply network, so that the sensor is arranged around two electric conductors in the single-phase power supply network.

[0094] Furthermore, for specified use in a three-phase power supply network, it is proposed to arrange the sensor around the three outer conductors and the neutral conductor, thus resulting in a total of four electrical conductors in the three-phase power supply network.

[0095] In particular, it is proposed that the through opening of the magnetic field sensitive element is circular in cross section, ie an oval having two semi-radii of equal length.

[0096] Furthermore, it is proposed in particular that the through opening of the magnetic field sensitive element has an elliptical cross section, ie an oval having two semi-radii of different lengths.

[0097] It is expressly pointed out that the feature that the through opening of the magnetic field sensitive element is shaped as an oval in cross section with two axes of symmetry is not essential in the sense of the invention.

[0098] Rather, other geometries of the magnetic field sensitive element are also conceivable here, which in particular allow a good compromise with regard to the abovementioned physical effects, in particular these geometries are also based on an oval cross section.

[0099] Depending on the geometry of the magnetic field-sensitive element, it is proposed that the geometry of the shield is also adapted accordingly.

[0100] In particular, it is also proposed here that the magnetic field sensitive element has a high magnetic permeability.

[0101] The "permeability" of a magnetic field sensitive element is understood to mean the magnetization of the material in an external magnetic field. The higher the permeability of the magnetic field sensitive element, the greater the ratio of the magnetic flux density in the magnetic field sensitive element to the strength of the magnetic field acting on the magnetic field sensitive element.

[0102] A magnetic field sensitive element having a high magnetic permeability results in a relatively high magnetic flux density being present in the magnetic field sensitive element even at low magnetic field strengths, thus increasing the sensitivity of the sensor and thereby helping the sensor to detect even small residual currents.

[0103] In particular, it is proposed that the magnetic field sensitive element has a permeability of 35,000 H / m (henry per meter) or more, preferably the magnetic field sensitive element has a permeability of 45,000 H / m or more, particularly preferably the magnetic field sensitive element has a permeability of 50,000 H / m or more. More preferably, the magnetic field sensitive element has a permeability of 60,000 H / m or more, preferably the magnetic field sensitive element has a permeability of 70,000 H / m or more, particularly preferably the magnetic field sensitive element has a permeability of 80,000 H / m or more. More preferably, the magnetic field sensitive element has a permeability of 90,000 H / m or more, preferably the magnetic field sensitive element has a permeability of 100,000 H / m or more, particularly preferably the magnetic field sensitive element has a permeability of 110,000 H / m or more. More preferably, the magnetic field sensitive element has a magnetic permeability of 120,000 H / m or more, preferably, the magnetic field sensitive element has a magnetic permeability of 130,000 H / m or more, and particularly preferably, the magnetic field sensitive element has a magnetic permeability of 140,000 H / m or more. In particular, the magnetic field sensitive element has a magnetic permeability of 150,000 H / m or more.

[0104] The permeability values ​​given above apply when the magnetic field oscillates at 50 Hz.

[0105] It is clearly pointed out that the above values ​​of the magnetic permeability of the magnetic field sensitive element should not be understood as definite limits, but rather should be able to be exceeded or exceeded on an engineering scale without departing from the described aspects of the present invention. In short, these values ​​should provide an indication of the magnitude of the magnetic permeability of the magnetic field sensitive element proposed herein.

[0106] In particular, the magnetic field sensitive element has a magnetic saturation flux density of 1 T or more, preferably, the magnetic field sensitive element has a magnetic saturation flux density of 1.1 T or more, and particularly preferably, the magnetic field sensitive element has a magnetic saturation flux density of 1.2 T or more. In particular, the magnetic field sensitive element has a magnetic saturation flux density of 1.3 T or more.

[0107] It is clearly pointed out that the above values ​​of the magnetic saturation flux density of the magnetic field sensitive element should not be understood as definite limits, but rather should be able to be exceeded or exceeded on an engineering scale without departing from the described aspects of the present invention. In simple terms, the values ​​should provide an indication of the magnitude of the magnetic saturation flux density of the magnetic field sensitive element proposed herein.

[0108] In particular, it is proposed here that the magnetic field sensitive element has a high degree of linearity with respect to magnetic permeability, in particular has a higher linearity with respect to magnetic permeability than ferrite material.In other words, it is proposed in particular not to use ferrite material for the magnetic field sensitive element.

[0109] The more linear the magnetic field sensitive element is with respect to the magnetic permeability, the higher the achievable measurement accuracy of the sensor.

[0110] In particular, the magnetic field sensitive element has a coercive force of 30 mA / cm or less, preferably, the magnetic field sensitive element has a coercive force of 20 mA / cm or less, and particularly preferably, the magnetic electromagnetic field sensitive element has a coercive force of 15 ma / Acm or less. More preferably, the magnetic field sensitive element has a coercive force of 10 mA / cm or less, preferably, the magnetic field sensitive element has a coercive force of 5 mA / cm or less, and particularly preferably, the magnetic electric field sensitive element has a coercive force of 2 mA / cm or less. More preferably, the magnetic field sensitive element has a coercive force of 1 mA / cm or less, preferably, the magnetic field sensitive element has a coercive force of 0.5 mA / cm or less, and particularly preferably, the magnetic electric field sensitive element has a coercive force of 0.2 mA / cm or less. In particular, the magnetic field sensitive element preferably has a coercive force of 0.1 mA / cm or less.

[0111] The coercivity values ​​given above apply when the magnetic field oscillates at 50 Hz.

[0112] A particularly high measurement accuracy can be achieved due to the low coercivity of the magnetically sensitive element, especially when the field strength of the magnetic field changes: the lower the coercivity of the magnetically sensitive element, the higher the measurement accuracy of the sensor.

[0113] It is to be clearly noted that the above values ​​of the coercivity of the magnetic field sensitive element should not be understood as definite limits, but rather should be able to be exceeded or exceeded on an engineering scale without departing from the described aspects of the present invention. In simple terms, the values ​​should provide an indication of the magnitude of the coercivity of the magnetic field sensitive element proposed herein.

[0114] In particular, it is proposed to select or manufacture the magnetic field sensitive element from a soft magnetic material.

[0115] In particular, the magnetic field sensitive element is made of an alloy having 70% by weight or more of iron, preferably 71.5% by weight or more of iron, particularly preferably 73% by weight or more of iron. In particular, the magnetic field sensitive element is made of an alloy having 73.5% by weight or more of iron.

[0116] In particular, the magnetic field sensitive element is made of an alloy containing 0.75-1.25% by weight of copper, preferably 0.85-1.15% by weight of copper, particularly preferably 0.95-1.05% by weight of copper. In particular, the alloy of the magnetic field sensitive element contains 1% by weight of copper.

[0117] In particular, the magnetic field sensitive element is made of an alloy containing 2 to 4% by weight of niobium, preferably 2.5 to 3.5% by weight of niobium, particularly preferably 2.8 to 3.2% by weight of niobium. In particular, the alloy of the magnetic field sensitive element contains 3% by weight of niobium.

[0118] In particular, the magnetic field sensitive element consists of an alloy with a boron content in the range of 5-9% by weight, preferably in the range of 6-8% by weight, particularly preferably in the range of 6.5-7.5% by weight. In particular, the alloy of the magnetic field sensitive element has a boron content of 7% by weight.

[0119] In particular, the magnetic field sensitive element is made of an alloy containing 14-17% by weight of silicon, preferably 15-16% by weight of silicon, particularly preferably 15.4-15.6% by weight of silicon. In particular, the alloy of the magnetic field sensitive element has a silicon content of 15.5% by weight.

[0120] It is expressly pointed out that the above values ​​of the alloy composition of the magnetic field sensitive element should not be understood as definite limits, but rather should be able to be exceeded or exceeded on an engineering scale without departing from the described aspects of the invention.

[0121] In particular, the magnetic field sensitive element is preferably made of a nanocrystalline soft magnetic material having a typical grain size in the range of 5 to 30 gm, preferably made of a nanocrystalline soft magnetic material having a typical grain size in the range of 7 to 20 gm, more preferably made of a nanocrystalline soft magnetic material having a typical grain size in the range of 8 to 15 gm.

[0122] In particular, the magnetic field sensitive element is produced from a strip having a particularly small strip thickness, since in this way, according to Maxwell's laws, eddy current losses in the magnetic sensitive element can be kept low.

[0123] In particular, the magnetic field sensitive element has a strip thickness in the range of 5 to 50 gm. The strip thickness of the magnetic field sensitive element is preferably in the range of 7.5 to 40 gm, particularly preferably in the range of 10 to 30 gm.

[0124] It is clearly noted that the above values ​​of the band thickness of the magnetic field sensitive element should not be understood as definite limits, but rather should be able to be exceeded or exceeded on an engineering scale without departing from the described aspects of the present invention. In short, the values ​​should provide an indication of the size of the band thickness of the magnetic field sensitive element proposed here.

[0125] In particular, the cross-sectional area of ​​the iron of the magnetic field sensitive element is 0.03 to 0.15 cm 2 In particular, the cross-sectional area of ​​the iron of the magnetic field sensitive element is preferably in the range of 0.04 to 0.12 cm. 2 Particularly preferably, the cross-sectional area of ​​the iron of the magnetic field sensitive element is in the range of 0.05 to 0.1 cm 2 The range is.

[0126] In particular, the magnetic field sensitive element has a height of 3 to 7 mm, preferably, the magnetic field sensitive element has a height of 3.4 to 6.6 mm, particularly preferably, the magnetic field sensitive element has a height of 3.8 to 6.2 mm.

[0127] It is expressly pointed out that the above values ​​of the cross-sectional area of ​​the iron and the height of the magnetic field sensitive element should not be understood as definite limits, but rather should be able to be exceeded or exceeded on an engineering scale without departing from the described aspects of the invention. In simple terms, these values ​​should provide an indication of the size of the cross-sectional area of ​​the iron and the height of the magnetic field sensitive element proposed herein.

[0128] In particular, it is proposed that the sensor determines the residual current according to the operating principle of a Forster probe.

[0129] In particular, the turns of the first main winding are equally spaced around the circumference of the magnetic field sensitive element.

[0130] In particular, the first main winding has a number of turns in the range of 25 to 150 turns, preferably in the range of 35 to 135 turns, and particularly preferably in the range of 40 to 130 turns. Furthermore, in particular, the first main winding has a number of turns in the range of 45 to 125 turns, preferably in the range of 50 to 120 turns, and particularly preferably in the range of 60 to 110 turns.

[0131] Advantageously, in order to ensure that a magnetic flux density that is as locally uniform as possible in the magnetic field sensitive element when the first main winding is energized, the number of turns of the first main winding proposed here makes it possible to achieve that the magnetic field sensitive element can be wound with as equal a distance as possible between the individual windings.

[0132] It is expressly pointed out that the above values ​​of the number of turns of the first main winding should not be understood as definite limits, but rather should be able to be exceeded or exceeded on an engineering scale without departing from the described aspects of the invention. In simple terms, these values ​​should provide an indication of the magnitude of the number of turns of the first main winding proposed herein.

[0133] In particular, the turns of the test winding are equally spaced around the entire circumference of the magnetic field sensitive element.

[0134] In particular, the test winding has a number of turns in the range of 3 to 40 turns, preferably in the range of 4 to 35 turns, particularly preferably in the range of 5 to 30 turns. Furthermore, in particular, the test winding has a number of turns in the range of 6 to 25 turns, preferably in the range of 8 to 22 turns, particularly preferably in the range of 10 to 18 turns.

[0135] Advantageously, in particular since the test windings can be arranged uniformly over the magnetic field sensitive element with equal spacing between adjacent windings, the number of turns of the test winding proposed herein makes it possible to achieve a particularly accurate determination of the magnetic flux density of the element sensitive to magnetic fields due to the inductive effect this causes in the test winding.

[0136] It is expressly pointed out that the above values ​​of the number of turns of the test windings should not be understood as strict ranges, but rather should be able to be exceeded or exceeded on an engineering scale without departing from the described aspects of the invention. In simple terms, these values ​​should provide an indication of the magnitude of the number of turns of the test windings proposed herein.

[0137] The range of the through openings of the magnetic field sensitive elements proposed here, in the case of an ideal functional design of the shield, results in an inner dimension of the through openings of the shield in the range of 18.2 to 30 mm, preferably in the range of 19.5 to 27.5 mm, particularly preferably in the range of 20.5 to 24.2 mm. Particularly preferably, the inner dimension of the through openings of the shield is in the range of 20.8 mm to 22.2 mm.

[0138] It is expressly pointed out that the above values ​​of the range of the inner dimensions of the through openings of the shield should not be understood as strict ranges, but rather should be able to be exceeded or exceeded on an engineering scale without departing from the described aspects of the invention. In simple terms, these values ​​should provide an indication of the size of the respective proposed ranges of the inner dimensions of the through openings of the shield.

[0139] Of course, any of the range limits recited for the internal dimensions may be combined with one another.

[0140] According to a preferred embodiment, the magnetically sensitive element is covered by an insulator, the insulator being disposed between the magnetically sensitive element and the first main winding, and between the magnetically sensitive element and the test winding.

[0141] In this regard, the following terminology is explained: By "insulator" is understood an element made of a material that has a particularly low electrical conductivity and therefore conducts electric current very little compared to the material that surrounds it.

[0142] In particular, the insulator may be formed in two parts, whereby it can be opened to accommodate the magnetic field sensitive element and subsequently closed again.

[0143] The two-part insulator has a form and / or force connection between the two parts of the insulator, which advantageously allows it to reliably surround the magnetic field sensitive element and does not unintentionally open and / or release the magnetic field sensitive element again.

[0144] In particular, the insulation preferably has a low hardness compared to the material of the windings, so that any friction that may occur between the insulation and the windings advantageously damages the insulation rather than the windings.

[0145] The insulator advantageously enables regional isolation of the magnetic field sensitive element from the first main winding and the test winding, and possibly the second main winding, thereby reducing possible damage to the windings.

[0146] If the insulator has a low hardness and / or a low modulus of elasticity as the material of the windings of the first main winding and the test winding, and possibly the second main winding, a preload can be set on the windings, which leads to an elastic deformation of the insulator and thus a positive coupling between the insulator and the windings, so that the windings are better fixed relative to one another, which advantageously increases the reliability of the sensor.

[0147] Furthermore, the insulator allows the distance between the winding and the magnetic field sensitive element to always be constant, which advantageously achieves that the physical operational connection between the winding and the magnetic field sensitive element remains constant, and therefore the accuracy of the determination of the sensor signal can advantageously be permanently maintained.

[0148] Preferably, the sensor comprises a second main winding, the second main winding surrounding the magnetically sensitive element and / or the insulator with a plurality of windings.

[0149] In this regard, the following terminology is explained: By "second main winding" is understood a main winding which is wound around the magnetic field sensitive element in addition to the first main winding.

[0150] In particular, the second main winding has a winding direction which is different from the winding direction of the first main winding.

[0151] In a specified operation of a sensor according to the first aspect of the invention having a first main winding and no second main winding, an alternating voltage is supplied to the first main winding, whereby each time the sign of the supply voltage changes, the current flow in the first main winding reverses sign.

[0152] Alternatively, the first main winding is supplied with a current source with alternating current directions. By using a current source, a higher measurement accuracy of the sensor can be advantageously achieved.

[0153] In other words, the first main winding has current flowing in periodically different directions during a designated operation of the sensor.

[0154] The time profile of current flow during a specified sensor operation in the first main winding may have a sinusoidal or rectangular shape, or other oscillatory shape.

[0155] An oscillating current flow in the first main winding is configured to induce a similarly oscillating magnetic flux density in the magnetic field sensitive element.

[0156] The sensor proposed here has two main windings, namely a first main winding and a second main winding.

[0157] Preferably, the number of turns of the second main winding is equal to the number of turns of the first main winding.

[0158] This allows the single main winding not to have to change sign of current flow direction in order for the sensor to operate as specified. Rather, each of the two main windings can be operated in a pulsed manner so that they alternate between having current flow and not having current flow.

[0159] If two main windings are wound around the magnetic field sensitive element with different rotational directions, the two main windings can be alternately connected to the same voltage or current source, and the voltage or current source can have a stationary constant output value, thereby inducing an alternating magnetic flux density in the magnetic field sensitive element. This advantageously allows a more favorable design of the operating circuit for a specified sensor operation. This allows a reduction in the common costs of the sensor and the operating circuit, even if an additional main winding is required.

[0160] In particular, the turns of the second main winding are equally spaced around the circumference of the magnetic field sensitive element.

[0161] In particular, the second main winding has a number of turns in the range of 25 to 150 turns, preferably in the range of 35 to 135 turns, and particularly preferably in the range of 40 to 130 turns. Furthermore, in particular, the second main winding has a number of turns in the range of 45 to 125 turns, preferably in the range of 50 to 120 turns, and particularly preferably in the range of 60 to 110 turns.

[0162] Advantageously, the number of turns of the second main winding proposed here makes it possible to achieve that the individual windings can be wound around the magnetic field sensitive element with as equal a distance between them as possible, in order to generate a locally uniform magnetic flux density in the magnetic field sensitive element as possible when current is applied to the second main winding.

[0163] It is expressly pointed out that the above values ​​of the number of turns of the second main winding should not be understood as strict ranges, but can be exceeded or exceeded on an engineering scale without departing from the described aspects of the invention. In simple terms, these values ​​should provide an indication of the magnitude of the number of turns of the second main winding proposed herein.

[0164] According to a particularly expedient embodiment, the sensor comprises a spacer ring, which is arranged between the inner wall of the shield and the first main winding.

[0165] In this regard, the following terminology is explained: By "spacer ring" is understood a ring-shaped element arranged to be placed between the inner wall of the shield and the first main winding of the sensor.

[0166] In particular, the spacer ring is configured to reduce or fill the radial gap in the receiving space between the inner wall of the shield and the main winding.

[0167] In particular, the spacer ring is configured to fill the axial gap between the first shield part and the second shield part, so that as soon as the two shield parts are each placed against the spacer ring, the spacer ring can define the width of the circumferential gap.

[0168] In particular, the spacer ring is made of plastic or another material that has a relatively low specific electrical conductivity.

[0169] Advantageously, the spacer ring can also be used to achieve that the wires of the main winding and / or the test winding are protected during assembly of the sensor. The spacer ring can be inserted together with the magnetic field sensitive element, which is already wound with the main winding or multiple main windings and the test winding, in particular into the first part of the shield, in particular into the part of the shield, which is at least partially designated and overlapped by another part of the shield at its outer surface. The magnetic field sensitive element can thus be inserted carefully under visual supervision into the first part of the shield, the magnetic field sensitive element being protected from mechanical loads on its inside by the spacer ring, in particular the winding arranged around the magnetic field sensitive element being protected from mechanical loads on its inside by the spacer ring. The second part of the shield can then be fitted in such a way that the winding is already protected from mechanical loads by the spacer ring and the overlapping first part of the shield. In so far, the spacer ring can advantageously improve the mechanical protection of the sensitive component, even if visual access to the particularly sensitive component is not possible during assembly of the second part of the shield.

[0170] Preferably, a spacer ring is proposed here which has an insert inside its base material made of a material with a relatively high magnetic permeability, in particular a permeability that substantially corresponds to the magnetic permeability of the shield, in particular this insert being completely surrounded by the base material of the spacer ring so that it is insulated by the base material with a relatively low electrical conductivity.

[0171] This advantageously achieves that leakage of the magnetic field arising from the magnetic field sensitive element in the circumferentially extending gap during the specified operation of the sensor can be reduced as a result of the high magnetic permeability of the spacer ring, thereby advantageously increasing the measurement accuracy of the sensor and also reducing the energy consumption of the sensor.

[0172] Optionally, the shield has a coating, in particular an electrically insulating coating.

[0173] In this regard, the following terminology is explained: By "coating" is understood an adherent layer of amorphous material on the surface of the shield.

[0174] In particular, the coating is designed such that it conducts electric current particularly poorly, and therefore the coating has a particularly low electrical conductivity.

[0175] In particular, the coating preferably consists of an epoxy resin.

[0176] In particular, the coating is provided on the shield so as to cover at least a partial surface of the outer shield surface which is designated to be located near the printed circuit board.

[0177] Advantageously, in this manner, insulation of the shield relative to the designated circuit board can be achieved, thereby advantageously preventing short circuits between the shield and the designated circuit board.

[0178] According to an expedient embodiment, the shield has a material thickness in the range from 0.25 mm to 0.45 mm, preferably in the range from 0.3 mm to 0.4 mm, particularly preferably in the range from 0.32 mm to 0.38 mm.

[0179] In this regard, the following terminology is explained: "Material thickness" or material thickness is understood as the extension of an object in the direction normal to a surface.

[0180] By "eddy currents" is understood the electric currents induced in an electric conductor expanding in a time-varying magnetic field and / or moving in a time-constant but spatially inhomogeneous magnetic field. If the conductor has a finite electrical resistance, it will heat up as a result of the eddy currents. This amount of energy converted into heat is called "eddy current losses".

[0181] It is now proposed to reduce the material thickness of the shielding of the magnetic field sensitive element together with at least one main winding and a test winding around the magnetic field sensitive element.

[0182] The possibility of reducing the material thickness in the region of the shield is based on innovations in the field of shield manufacturing.

[0183] In particular, the shield is deep-drawn or injection-molded.

[0184] This advantageously allows cost savings to be achieved compared to a larger material thickness of the shield.

[0185] During the designated operation of the sensor, the magnetic field sensitive element has an oscillating magnetic flux density. Since the shield also consists of a material with good electrical conductivity, the change in magnetic flux density of the magnetic field sensitive element exerts an inductive effect on the shield, which is undesirable since it generates eddy current losses.

[0186] Reducing the material thickness of the shield can advantageously reduce eddy current losses that occur during designated operation of the sensor.

[0187] This can advantageously reduce the energy consumption of the sensor and increase the measurement accuracy of the sensor.

[0188] It is expressly pointed out that the above values ​​of the shielding material thickness should not be understood as strict ranges, but rather should be able to be exceeded or exceeded on an engineering scale without departing from the described aspects of the invention. In simple terms, these values ​​should provide an indication of the magnitude of the shielding material thickness proposed herein.

[0189] Preferably, the gap extending in the circumferential direction has a gap width in the range of 0.1 mm to 2.0 mm, more preferably in the range of 0.3 mm to 1.7 mm, and particularly preferably in the range of 0.6 mm to 1.3 mm.

[0190] In this regard, the following terminology is explained: By "gap width" is meant the width of the gap. In particular, the width of the gap is meant the width of the gap extending in the circumferential direction on the inner wall of the shielding body.

[0191] The circumferentially extending gaps of the shield are particularly advantageous, since otherwise the shield also constitutes a winding of a well-conducting material around the magnetic field-sensitive element, on which a relatively strong inductive effect is exerted during the designated operation of the sensor, where the magnetic flux density oscillates in the magnetic field-sensitive element, which leads to increased eddy current losses in relation to the shield, which can lead to increased energy consumption of the sensor and reduced measurement accuracy of the sensor.

[0192] However, the circumferential gaps in the sensor shield also result in a reduction of the magnetic field around the magnetic field sensitive element, especially since the magnetic permeability of air within the circumferential gaps is much lower than the magnetic permeability of the shield.

[0193] Therefore, if the width of the circumferential gap is too large, various kinds of physical effects will occur, which in turn will have a negative effect on the energy consumption of the sensor and on the measurement accuracy of the sensor.

[0194] A specific range of the gap width of the circumferential gap is therefore proposed, whereby, based on different physical effects, an optimum can be advantageously achieved between the measurement accuracy and optimal sensitivity of the sensor when the width of the circumferential gap is too small and when the width of the circumferential gap is too large.

[0195] Furthermore, it can be achieved that, due to the width of the circumferential gap proposed here, the energy consumption for the operation of the sensor can be advantageously minimized.

[0196] It is expressly pointed out that the above values ​​of the gap width of the circumferentially extending gap should not be understood as strict limits, but rather should be able to be exceeded or exceeded on an engineering scale without departing from the described aspects of the invention. In simple terms, these values ​​should provide an indication of the size of the gap width of the circumferentially extending gap proposed herein.

[0197] According to an expedient embodiment, the sensor comprises an electrical connector, the electrical connector comprising a support plate, a connector neck and a number of electrical contacts. - the electrical connector has at least two electrical contacts per winding; the electrical contacts are arranged radially outside the outer wall of the shield; the support plate is disposed between the shield outer wall and the first main winding; a connector neck extending through the opening in the outer wall of the shield and connecting the support plate and the electrical contacts to each other; the support plate and the connector neck each have a corresponding cavity configured to receive two electrical wires in operative connection with each winding from the receiving space and pass them from the receiving space through openings in the shield to the electrical contacts; The cavity has a cutout in a direction parallel to the outer wall of the shield, through which an electric wire can be inserted into the central region of the cavity.

[0198] In this regard, the following terminology is explained: By "electrical connector" is understood an element that is adapted to be attached to a sensor and that has at least the necessary number of accessible electrical contacts.

[0199] In particular, the connector makes it possible for electrical and / or electronic components of the sensor to be electrically connected with electrical contacts of the connector, which electrical contacts have relatively good accessibility.

[0200] In particular, the connector preferably allows, at least indirectly, for the electrical contacts to be located in a fixed position relative to the sensor.

[0201] Overall, the connector therefore particularly and advantageously enables the sensor to be used with a fixed relative positioning between the magnetic field sensitive element and the electrical contacts, and the electronic and / or electrical elements of the sensor can be electrically connected to the electrical contacts already during the manufacture of the sensor.

[0202] The sensor can therefore be advantageously connected to the substrate directly by soldering or indirectly via the electrical contacts of the electrical connector by other contact elements, in particular plugs, such that the relative position of the magnetic field sensitive element to the substrate can be fixed by the connection made possible at least indirectly by the electrical connector.

[0203] In particular, electrical connectors have a plastic as a substrate, especially a plastic with a relatively low electrical conductivity.

[0204] In particular, the electrical contacts of the electrical connector are at least partially surrounded by the substrate of the connector, so that there is a force-locking and / or form-locking connection between the substrate and the electrical contacts. Furthermore, in particular, the electrical contacts are arranged spatially separated from one another by the substrate of the electrical connector, so that advantageously, there is no direct electrical contact between two electrical contacts, thereby preventing short circuits between individual electrical and / or electronic elements of the sensor.

[0205] By "support plate" is understood a region of the electrical connector which is arranged to provide at least an indirect connection in a form-locking and / or force-locking manner between the magnetic field sensitive element and the electrical connector.

[0206] In particular, the support plate can be accommodated in the accommodation space of the shield, in particular between the shield and the main winding, in particular between the main winding and the outer shield wall of the shield.

[0207] In particular, the support plate is preferably designed to be inserted together with the magnetic field sensitive element and the winding surrounding the magnetic field sensitive element into the shield, whereby advantageously the support plate provides additional protection for the winding against mechanical loads during installation in the shield.

[0208] By "connector neck" is understood the area of ​​the electrical connector that is configured to connect the support plate and the electrical contacts to each other.

[0209] By "electrical contacts" is understood elements of an electrical connector that are configured to make contact between electrical and / or electronic elements of the sensor.

[0210] In particular, the electrical contacts are formed in such a way that they protrude in two directions from the base material of the electrical connector. In that case, it should be borne in mind that in particular the contacts can be contacted with the electrical and / or electronic components of the sensor at the protruding ends of the contacts. Furthermore, it should be borne in mind that the contact with the operating circuit of the sensor can be contacted at different protruding ends of the electrical contacts, in particular by soldering or by a plug connector corresponding to the electrical contact or contacts.

[0211] In particular, the electrical contact consists of an alloy which contains nickel in the range of 17-19% by weight, preferably 17.5-18.5% by weight, particularly preferably 18% by weight of nickel.

[0212] In particular, the electrical contact consists of an alloy which contains 18-22% by weight of zinc, preferably 19-21% by weight of zinc, particularly preferably 20% by weight of zinc.

[0213] In particular, the electrical contacts are made of an alloy containing 58% by weight or more of copper, preferably 60% by weight or more of copper, particularly preferably 61% by weight or more of copper, more preferably 62% by weight or more of copper, even more preferably 63% by weight or more of copper, particularly preferably 64% by weight or more of copper.

[0214] The above-described alloy compositions for the electrical contacts advantageously allow for very good electrical conductivity, while at the same time providing a relatively high elastic modulus and very good immersion tinning and soldering properties.

[0215] It is expressly pointed out that the above values ​​for the alloy composition of the electrical contacts should not be understood as definite limits, but rather should be able to be exceeded or exceeded on an engineering scale without departing from the described aspects of the invention. In simple terms, these values ​​should provide an indication of the magnitude of the alloy composition of the electrical contacts proposed herein.

[0216] In particular, the electrical contacts have a gold coating, which makes it possible to advantageously improve the electrical conductivity of the electrical contacts.

[0217] By "opening" is understood an area in the shield through which a connector neck of an electrical connector connecting the support plate and the electrical contacts to one another can extend from the receiving space in the shield to an area outside the shield, so that the electrical contacts of the electrical connector can be arranged outside the shield. For this purpose, the shield has in particular an opening corresponding to the connector neck.

[0218] It should be kept in mind that in the case of a two-part shield, one or both parts of the shield may have a void that forms the opening after joining of the shield parts.

[0219] In particular, the opening is in the region of the outer wall of the shield.

[0220] By "void space" is understood an area of ​​the cross-section of the element which is not formed by the substrate of the element and which can therefore be penetrated by other objects without damaging the element.

[0221] In particular, the voids are channels through the substrate of the component.

[0222] More particularly, the cavity is formed in the form of a recess in the substrate of the component, whereby another object can be inserted into the cavity through the opening of the recess.

[0223] By "corresponding cavities" in the connector neck and the support plate it is understood that the cavities extend through both the support plate and the connector neck with a substantially constant contour shape in the main direction of extension of the cavities.

[0224] By "electric wire" is understood a flexible metal that is thin in the longitudinal direction. In particular, the electric wire has a circular cross section. In particular, the electric wire has a number of strands. In particular, the electric wire has a high proportion of copper.

[0225] A "notch" is understood to be a pointed or wedge-shaped cut.

[0226] The sensor according to the first aspect of the invention comprises a number of electric and / or electronic components. During a specified operation of the sensor, an electric current is generated in or actively supplied to the electronic and / or electrical components.

[0227] These electrical and / or electronic components of the sensor must be designated and arranged in the receiving space of the shield and must be electrically contacted from outside the shield.

[0228] The simplest form of electrical contact is based on wires connected to electrical and / or electronic components being passed through the shield and soldered on the outside to a circuit board carrying the operating circuitry of the sensor.

[0229] In this solution, there are many different sources of damage to the wire and thus to the sensor as a whole, which can lead to the failure of the sensor. On the one hand, the wire, which in most cases has a very small conductor cross section, can be easily destroyed by mechanical loads, especially shear loads in the area of ​​the shield, or tensile loads between the windings and of the wire-to-circuit board connections. Such tensile loads can occur during assembly of the sensor or even during operation of the sensor, when relative movements with the magnetic field sensitive element and contacts with the wire-to-circuit board take place.

[0230] It is now proposed to make the wires of the sensor mechanically and electrically connectable by means of an electrical connector, thereby advantageously increasing the robustness and availability of the sensor.

[0231] The electrical connector proposed herein comprises a support plate arranged in the receiving space of the shield. As a second region of the electrical connector, a connector neck extends from the support plate. The connector neck extends in particular through the shield, in particular in the region of the shield outer wall. A number of electrical contacts are connected to the connector neck, which are arranged to be in electrical contact with electrical and / or electronic components of the sensor.

[0232] The support plate allows for a force- and / or form-locking connection of the electrical connector with the sensor, in particular with the shield of the sensor.

[0233] The connector neck is designed to accommodate the electric wires and thus protect them from mechanical loads, particularly in the region of the shield, for which the connector neck and the support plate have corresponding cavities into which the electric wires can be inserted and which protect them from external mechanical loads.

[0234] Additionally, the connector neck fixes the relative position between the magnetic field sensitive element of the sensor and the electrical contacts configured to make electrical contact therewith, and electrical wires can be threaded through corresponding cavities in the connector neck and support plate to the electrical contacts where they can be contacted.

[0235] The connector neck and the corresponding cavities of the support plate are finished in the form of troughs that are open in a direction transverse to the longitudinal extension of the corresponding cavities, so that the wires can be inserted into the cavities not only longitudinally but also transversely to the longitudinal direction. This design allows advantages in assembling the sensor, since the wires can be inserted longitudinally and transversely to the longitudinal direction, one after the other and in bundles, which significantly facilitates the laying of the wires in the cavities.

[0236] The corresponding cavities in the connector neck and in the support plate have notches extending transversely to the longitudinal axis of the corresponding cavities, with the tip of the notch pointing towards the cavities. The notches enable the individual wires or the wires of the bundle to be inserted transversely into the cavities in a simple manner, with each wire having to pass through the narrowing of the notch. The narrowing of the notch is designed in such a way that when the wire is inserted into the cavities, it can only leave the cavities transversely to the longitudinal direction of the cavities with greater effort and thus remain in a designated protective area of ​​the cavities. This makes it possible to simplify the assembly of the wires and ensures that the wires are already protected, especially against mechanical loads, after their insertion into the cavities.

[0237] According to a second aspect of the invention, there is provided a protective circuit breaker for interrupting a circuit in case of a residual current exceeding a limit value occurring in the circuit, comprising a sensor according to the first aspect of the invention, an operating circuit, an electronic data processing and evaluation unit and a switching device, - the sensor is disposed around at least two electrical conductors forming a circuit; a switching device is set to interrupt the circuit; an operating circuit is configured to operate the sensor; an electronic data processing and evaluation unit is arranged to evaluate the sensor signals of the sensors, The electronic data processing and evaluation unit is configured to drive the switching device with a current strength greater than a limit value, in particular an adjustable limit value, so that the switching device interrupts the circuit if a residual current is recognized, in particular if a residual current is recognized in a bi-current sensitive manner.

[0238] In this regard, the following terminology is explained: By "protective circuit breaker" is understood a device which is set to shut down the voltage of a monitored circuit if a defined residual, in particular an adjustable residual current, is exceeded in the circuit monitored by the protective circuit breaker. In this way the risk of residual currents to persons and infrastructure can be advantageously reduced.

[0239] By "operating circuit" is understood a circuit for active or passive operation of the sensor, in particular an operating circuit which is arranged to supply a voltage to the first main winding and / or the second main winding of the sensor.

[0240] Furthermore, the operating circuit is especially designed to tap off the voltage at a test winding of the sensor and transmit it as a signal to a data acquisition and evaluation unit.

[0241] Likewise, the operating circuit is also set up, in particular, to tap the voltage at the first main winding and / or the second main winding of the sensor and transfer it as a signal to the data acquisition and evaluation unit.

[0242] In particular, it should be borne in mind that the operating circuit also comprises a power consumption measuring device arranged to evaluate the power consumption of the test winding and / or the first main winding and / or the second main winding.

[0243] An "electronic data processing and evaluation unit" is an electronic unit which organizes and processes large amounts of data with the goal of obtaining information about these data or modifying these aspects of the data, in which case the data is compiled in the form of data sets, processed in a defined manner by a person or machine, and the results are output.

[0244] By "data" is understood in particular the value of a measured value, in particular a sensor signal, or any other physical or chemical measurand or quantity.

[0245] By "switching device" is understood a device arranged to shut down the voltage supply of a circuit, in particular a circuit monitored by a circuit breaker.

[0246] By "circuit" is understood an electric circuit consisting of a diameter of a conductor which represents a closed path.

[0247] By "sensor signal" is understood a state quantity provided by a sensor. In particular, the sensor signal is set in such a way that it can be inferred from the sensor signal by a physical and / or chemical dependence on the residual current of the circuit monitored by the sensor. In particular, the residual current monitored by the sensor can be calculated directly from the sensor signal. In particular, the sensor signal is a determinable current magnitude and / or a determinable voltage.

[0248] "Current intensity" is understood to mean a current that determines the current in the form of a physical quantity, in particular the current in an electric circuit. In this case, the current intensity is related to a suitably oriented surface, in particular the cross section of an electric conductor. In this case, the current intensity is the amount of charge that has flowed through the cross section and is related to the period of observation.

[0249] In particular, the sensor signal is understood to mean the power consumption of the first main winding, which can be converted into a residual current according to mathematical rules.

[0250] By "limit value" is understood a defined value of a state quantity, in particular a residual current, which, if exceeded in a circuit monitored by a protective circuit breaker, the switching device must at the latest shut down the voltage supply of the monitored circuit by the protective circuit breaker. In particular, the limit value of the circuit breaker can be adjustable.

[0251] That is, what is specifically proposed here is a circuit breaker that utilises a sensor according to the first aspect of the invention for monitoring a circuit.

[0252] Needless to say, the advantages of the sensor for determining the residual current according to the first aspect of the invention also apply directly to protective circuit breakers comprising a protective circuit breaker according to the first aspect of the invention, as described above.

[0253] This advantageously achieves in particular a protective circuit breaker that is more sensitive to residual currents, so that the protective circuit breaker can interrupt the circuit even if the residual current in the monitored circuit is very small, and at the same time advantageously achieves a particularly low probability that the protective circuit breaker will erroneously detect a residual current that would erroneously exceed the limit current when switching on the monitored circuit.

[0254] It is expressly pointed out that the subject matter of the second aspect may be advantageously combined with the subject matter of the preceding aspects of the invention either individually or cumulatively in any combination.

[0255] According to a third aspect of the present invention, the problem is solved by a charging cable for charging an electric vehicle, the charging cable comprising a sensor according to the first aspect of the present invention and / or a protective circuit breaker according to the second aspect of the present invention.

[0256] In this regard, the following terminology is explained: By "charging cable" is understood an electrical connection that is designed to connect an electric vehicle to a power source, in this case the charging cable being designed to charge the traction battery of the electric vehicle, in particular the charging cable having a monitoring device for any residual current present.

[0257] By "electric vehicle" is understood a vehicle which is at least partially driven by an electric motor. In particular, an electric vehicle is not tethered to a track or at least not permanently tethered to a track.

[0258] There is now proposed a charging cable for charging a battery of an electric vehicle, comprising a protective circuit breaker according to the second aspect of the invention and / or a sensor according to the first aspect of the invention.

[0259] Needless to say, the advantages of the sensor for determining a residual current according to the first aspect of the invention and / or the protective circuit breaker for interrupting the circuit if a residual current occurs in the circuit, as described above, extend directly to a charging cable for charging an electric vehicle, which charging cable comprises a sensor according to the first aspect of the invention and / or a protective circuit breaker according to the second aspect of the invention.

[0260] It is expressly pointed out that the subject matter of the third aspect may be advantageously combined with the subject matter of the preceding aspects of the invention either individually or cumulatively in any combination.

[0261] According to a fourth aspect of the present invention there is provided a charging station for charging electric vehicles, the charging station comprising a sensor according to the first aspect of the present invention and / or a circuit breaker according to the second aspect of the present invention.

[0262] In this regard, the following terminology is explained: By "charging station" or "wall charging station" is understood a charger for charging electric vehicles. In the case of a wall charging station, the charging station is in particular designed to be mounted on a wall. In particular, the charging station is a mobile device that can be installed in different ways at different locations. In particular, the charging station or wall charging station, besides the plug-in connection of the charging cable for connecting the charging station with the electric vehicle and for connecting the charging station to the power supply network, also provides other functions, in particular a monitoring device for any residual currents that may occur.

[0263] Proposed herein is a charging station for charging electric vehicles, comprising a protective circuit breaker according to the second aspect of the invention and / or a sensor according to the first aspect of the invention.

[0264] Needless to say, the advantages of the sensor for determining the residual current according to the first aspect of the invention and / or the protective switch for interrupting the circuit in case of a residual current exceeding a limit value according to the second aspect of the invention extend directly to a charging station for charging electric vehicles, as described above, which comprises a sensor according to the first aspect of the invention and / or a protective switch according to the second aspect of the invention.

[0265] It is expressly pointed out that the subject matter of the fourth aspect can be advantageously combined with the subject matter of the previous aspects of the invention individually or cumulatively in any combination. Further advantages, details and features of the invention will become apparent from the examples described hereinafter. [Brief description of the drawings]

[0266] [Figure 1] FIG. 1 shows a schematic diagram of the arrangement of a sensor according to the invention in a circuit. [Diagram 2] FIG. 2 is a schematic diagram showing the physical interactions when the circuit is turned on. [Diagram 3] FIG. 3 is a diagram showing a schematic diagram of the dynamic course of the magnetic flux density over time at an exemplary location in a magnetic field sensitive element when the circuit is turned on. [Figure 4] FIG. 4 is a schematic diagram showing the physical relationship between the width of the magnetic field sensitive element, the profile of the sensor's tendency to malfunction depending on the width, and the profile of the sensor's minimum measurable residual current depending on the width. [Diagram 5] FIG. 5 is a schematic cross-sectional view of a sensor according to the present invention. [Figure 6] 6a to 6g are schematic diagrams of an electrical connector. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0267] In the following description, the same reference numbers indicate the same parts or features, so that the description given for a part with reference to a figure also applies to the other figures, thereby avoiding repetition of the description. Moreover, individual features described in connection with one embodiment can also be used separately in other embodiments.

[0268] A sensor 100, shown diagrammatically in FIG. 1, is disposed about electrical conductors 110, 120 through which specified electrical currents 112, 114 flow in and out of a circuit (not shown) that is monitored by the sensor 100.

[0269] In that case, current 112 flows into a circuit (not shown) monitored by sensor 100 through outer conductor 110 and flows out again through neutral conductor 120 .

[0270] When a voltage source (not shown) in a circuit (not shown) is turned on, a dynamic physical interaction coupling is created between the magnetic fields 114, 124 generated around the electrical conductors 110, 120 and the regional magnetic flux densities 116, 118 in the magnetic field sensitive element 10, as shown in FIG.

[0271] The magnetic fields 114, 124 originating from the electrical conductors 110, 120 have a regionally and temporally limited effect on the magnetic field sensitive element 10 when a voltage supply source (not shown) is turned on, thereby producing regionally opposite magnetic flux densities 116, 126 in the magnetic field sensitive element 10 for a short period of time.

[0272] It is observed that the temporary and regionally opposite magnetic flux densities 116, 126 in the magnetic field sensitive element 10 result in a dynamic behavior of the magnetic flux density in the form of an oscillation of the magnetic flux density 132 during the compensation process in FIG. 3 against time 130 at an exemplary location (not shown) in the magnetic field sensitive element 10.

[0273] This oscillation of the magnetic flux density 132 as a result of turning on a current source (not shown) for the observed circuit (not shown) undergoes a decaying transition and approaches its time limit along an asymptote 132, 134.

[0274] In that case, a brief oscillation of the magnetic flux density 132 leads to a physical interaction (not shown) with the test winding (not shown) and / or the first main winding and / or the second main winding, which results in a sensor signal (not shown), which can be interpreted as a residual current (not shown) exceeding a defined limit value (not shown), which can also be described as a switch-on error.

[0275] The relationship between the inner width 12 of the through opening (not shown) of the magnetic field sensitive element 10 shown in Figure 4, the tendency for malfunction 140 of a protective circuit breaker (not shown) for which the sensor 100 is specified and the minimum residual current 150 measurable by the sensor 100 indicates that there is an optimal value 160 for the inner width 12 of the through opening (not shown) of the magnetic field sensitive element 10 at which a good compromise is found between the minimum measurable residual current 150 and the tendency for malfunction 140.

[0276] This optimum value 160 is located at the intersection of the profiles 142, 152, upon inspection of the diagram presented here.

[0277] Additionally, an optimum range 165 for the inner width 12 of the through aperture (not shown) of the magnetic field sensitive element 10 has been identified, which is located around the optimum value 160 .

[0278] The sensor 100 of FIG. 5 essentially consists of a magnetic field sensitive element 10, an insulator 20 surrounding the magnetic field sensitive element 10, a main winding 30, a test winding (not shown), a spacer ring 40, a shield 50, an electrical connector 60, and a number of electrical contacts 70.

[0279] The insulator 20 is formed in two parts, the individual parts (not shown) of the insulator 20 being form-fittingly connected to one another.

[0280] The main winding 30 is connected by electrical wires 75 to electrical contacts 70 carried by the electrical connector 60 .

[0281] The shield 50 is formed in two parts and defines a circumferentially extending gap 55 on the shield inner wall 58 .

[0282] The electrical connector 60 of FIG. 6 essentially consists of a support plate 80, a connector neck 90, and a plurality of electrical contacts 70.

[0283] In figure 6b) a three-dimensional view of the electrical connector 60 is shown.

[0284] In FIG. 6a) a front view of the electrical connector 60 is shown, which is seen from the outside relative to the designated sensor.

[0285] In figure 6c) there is shown a top view of the electrical connector 60. Further, the section lines AA and BB are shown.

[0286] In figure 6d) cross section AA of the electrical connector 60 is shown.

[0287] In figure 6e) cross section BB of the electrical connector 60 is shown.

[0288] In FIG. 6f) a front view of the electrical connector 60 is shown, the front view being seen from the inside relative to the designated sensor.

[0289] In figure 6g) a side view of the connector 60 is shown.

[0290] The support plate 80 is configured to be accommodated in an accommodation space (not shown) of a shield (not shown).

[0291] The connector neck 90 connects the plurality of electrical contacts 70 with the support plate 80 .

[0292] The connector neck 90 has a cavity 92 configured to receive two electrical wires (not shown) operatively associated with each winding (not shown) from the receiving space (not shown) and to pass them from the receiving space (not shown) through openings (not shown) in the shield outer wall (not shown) to the electrical contacts (70).

[0293] The cavity 92 further has a notch 94 oriented parallel to the outer wall of the shield (not shown) through which electrical wires (not shown) can be placed in a central region (not shown) of the cavity 92 .

[0294] Through the notches 94, it is made possible that the wires (not shown) can be inserted individually or in bundles simply laterally into the cavity 92, in which case the notch 94 must be passed by each wire (not shown) at its narrowing (not shown). The narrowing (not shown) of the notch 94 ensures that the wires (not shown), once placed in the cavity 92, can only with great effort exit the cavity 92 again laterally relative to the longitudinal direction (not shown) of the cavity 92, and therefore remain in the designated protective area (not shown) of the cavity 92. [Explanation of symbols]

[0295] 10 Magnetic field sensitive elements 12 Inner width 20 Insulators 30 Main Winding 40 Spacer ring 50 Shield 55 Circumferential gap 58 Shielding Inner Wall 60 Electrical Connectors 70 Electrical Contacts 75 Electric wire 80 Support Plate 90 Connector neck 92 Vacant Space 94 Notch 100 Sensors 110 Electrical conductor / outer conductor 112 Current direction 114 Magnetic field 116 Magnetic Flux Density 120 Electrical Conductor / Neutral Conductor 122 Current direction 124 Magnetic field 126 Magnetic Flux Density 130 Timeline 132 Magnetic Flux Density Vibration 134 Asymptote 136 Asymptote 140 False trigger tendency 142 False trigger tendency profile 150 Minimum measurable residual current 152 Minimum measurable residual current profile 160 Best Locations 165 Optimal Range

Claims

1. A sensor (100) for determining residual current in a bicurrent-sensitive manner, comprising: - the sensor (100) comprises a magnetic field sensitive element (10), a first main winding (30), a test winding and a shield (50); - the magnetic field sensitive element (10) has a through opening, the through opening of the magnetic field sensitive element (10) being shaped as an oval in cross section with two axes of symmetry; - the first main winding (30) and the test winding each having a plurality of windings surround the magnetic field sensitive element (10); the shield (50) has an accommodation space configured to accommodate the magnetic field sensitive element (10), the first main winding (30) and the test winding; - the containment space of the shield (50) is radially defined by an outer shield wall and an inner shield wall (58), the shielding inner wall (58) defines a through opening in the shielding (50), the through opening in the shielding (50) being shaped as an oval with two axes of symmetry; - the shield (50) has a circumferentially extending gap (55) in the region of the shield inner wall (58), - said sensor (100) is arranged to be placed around at least two electrical conductors (110, 120); - a sensor in which the through opening of the magnetic field sensitive element (10) has at least one inner width along an axis of symmetry, The at least one inner width is in the range of 25.2 to 32 mm, preferably 25.5 to 29 mm, particularly preferably 25.8 to 27 mm; The sensor, wherein the magnetic field sensitive element has a coercive force of 30 mA / cm or less.

2. 2. The sensor (100) of claim 1, wherein the magnetic field sensitive element (10) is covered by an insulator (20), and the insulator (20) is disposed between the magnetic field sensitive element (10) and the first main winding (30), and between the magnetic field sensitive element (10) and the test winding.

3. The sensor (100) of claim 1 or claim 2, characterized in that the sensor (100) has a second main winding (30), the second main winding (30) surrounding the magnetic field sensitive element (10) and / or the insulator (20) with multiple turns.

4. The sensor (100) according to any one of claims 1 to 3, characterized in that the sensor (100) comprises a spacer ring (40), the spacer ring (40) being disposed between the inner wall of the shield and the first main winding (30).

5. The sensor (100) according to any one of claims 1 to 4, characterized in that the shield (50) has a coating, in particular an electrically insulating coating.

6. The sensor (100) according to any one of claims 1 to 5, characterized in that the shield (50) has a material thickness in the range of 0.25 mm to 0.45 mm, preferably in the range of 0.3 mm to 0.4 mm, particularly preferably in the range of 0.32 mm to 0.38 mm.

7. The sensor (100) according to any one of claims 1 to 6, characterized in that the circumferentially extending gap (55) has a gap width in the range of 0.1 mm to 2.0 mm, preferably in the range of 0.3 mm to 1.7 mm, particularly preferably in the range of 0.6 mm to 1.3 mm.

8. The sensor (100) has an electrical connector (60), the electrical connector (60) having a support plate (80), a connector neck (90), and a plurality of electrical contacts (70); - said electrical connector (60) has at least two electrical contacts (70) for each winding; - said electrical contacts (70) are arranged radially outside said shield side walls, - the support plate (80) is arranged between the outer wall of the shield and the first main winding (30); - said connector neck (90) extends through an opening in said outer wall of the shield and connects said support plate (80) and said electrical contacts (70) together; - the support plate (80) and the connector neck (90) each have a corresponding cavity (92) configured to receive two electric wires (75) operatively associated with each winding from the receiving space and to pass them from the receiving space through openings in the outer wall of the shield to the electrical contacts (70); A sensor (100) according to any one of claims 1 to 7, characterized in that the cavity (92) has a notch (94) in a direction parallel to the outer wall of the shield, through which the electric wire (75) can be placed in the central region of the cavity (92).

9. A protective circuit breaker for interrupting a current circuit when a residual current in said circuit exceeds a limit value, said circuit breaker comprising a sensor (100) according to any one of claims 1 to 8, said circuit breaker comprising an operating circuit, an electronic data processing and evaluation unit and a switching device, - said sensor (100) is arranged around at least two electrical conductors (110, 120) forming said circuit; - the switching device is configured to interrupt the circuit; - said operating circuit is configured to operate said sensor (100); - said electronic data processing and evaluation unit is configured to evaluate the sensor signals of said sensor (100), - a protective circuit breaker, wherein the electronic data processing and evaluation unit is configured to operate the switching device with a current intensity greater than a limit value, in particular an adjustable limit value, so that the switching device interrupts the circuit if a residual current is recognized, in particular if a residual current is recognized in a bi-current sensitive manner.

10. A charging cable for charging an electric vehicle, the charging cable comprising a sensor (100) according to any one of claims 1 to 8 or a protective circuit breaker according to claim 9.

11. A charging station for charging electric vehicles, the charging station comprising a sensor (100) according to any one of claims 1 to 8 or a protective circuit breaker according to claim 9.

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