Current path diagnosis using an electronic fuse

Abstract

Method (100) for monitoring a circuit (1), in particular to enable predictive maintenance, wherein the method (100) comprises the following steps: - measuring (110) at least one parameter (I, U, T) at at least one measuring position (3), wherein the at least one measuring position (3) is located on or in the circuit (1), - acquiring (120) the at least one parameter (I, U, T), - calculating (130) at least one actual value (131) based on the at least one parameter (I, U, T), - determining (140) a deviation (142) of the at least one actual value (131) from a target value (141), - analyzing (150) the deviation (142), outputting (160) an analysis result (161) based on the analysis (150).

Description

The invention relates to a method having the features of independent claim 1, to a computing unit having the features of independent claim 11, to a measuring device having the features of independent claim 12, to a computer program product having the features of independent claim 13, to a non-volatile computer-readable storage medium having the features of independent claim 14 and to a vehicle having the features of independent claim 15.Measuring devices for measuring parameters such as voltage or current are known. These may be used to characterize and / or test circuits.The known devices and methods from the prior art, however, have different disadvantages. Thus, measurement tolerances are partly not taken into account or, if at all, they are not adapted. These may be unknown in advance. Furthermore, the measurements are not flexible in the arrangement of the measurement position and / or embossing position within the scope of the measurement. Knowledge or empirical values cannot also be used, in particular in order to sufficiently take account of modification processes. If components that have been tested little or completely new up to now are used, for example replacement parts which can also originate in particular from third-party providers, no sufficient adaptation of measurements and / or measurement tolerances can take place. Thus, altogether, sufficiently good and / or reliable predictive maintenance cannot be carried out. In this case, it is in particular not possible to distinguish changed measurement tolerances from actual errors or aging processes. In this case, for example, a measurement offset, in particular by a so-called ground shift, in particular a change in potentials or reference potentials, cannot be taken into account or not sufficiently.It is therefore an object of the present invention to at least partially overcome at least one of the disadvantages described above. In particular, it is the object of the invention to reliably determine temporal aging processes and / or changes. In this case, in particular, a distinction can be made between or taking account of, for example, time-variable, measurement tolerances and / or temperature changes. Thus, it may be provided to not only enable more precise detection of defects or faults which are occurring, but also to prevent unnecessary repair, maintenance and / or misdiagnoses.The above object is achieved by a method with the features of independent claim 1, by a computing unit with the features of independent claim 11, by a measuring device with the features of independent claim 12, by a computer program product with the features of independent claim 13, by a non-transitory computer-readable storage medium with the features of independent claim 14 and by a vehicle with the features of independent claim 15. Features and details which are described in connection with the method according to the invention naturally also apply in connection with the computing unit according to the invention and / or in connection with the measuring device according to the invention and / or in connection with the computer program product according to the invention and / or in connection with the non-volatile computer-readable storage medium according to the invention and / or in connection with the vehicle according to the invention and vice versa, so that with regard to the disclosure reference to the individual aspects of the invention is or can always be made mutually. In particular, advantages which are described within the scope of the first, second, third, fourth, fifth and / or sixth aspect also apply in each case to the first, second, third, fourth, fifth and / or sixth aspect.According to a first aspect of the invention, a method for monitoring a circuit, in particular in order to enable predictive maintenance, is provided, wherein the method comprises at least one, preferably all, of the following steps:measuring at least one parameter at at least one measurement position, wherein the at least one measurement position is located on or in the circuit,detecting the at least one parameter,calculating at least one actual value based on the at least one parameter,determining a deviation of the at least one actual value from a setpoint value,analysis of the deviation,outputting an analysis result based on the analysis.The method can serve to monitor the circuit, in particular the lines and / or electronic components, such as a (switchable) electronic trip unit or fuse, for example. Particularly preferably, measurement tolerances can be taken into account during the measurement. The method can accordingly be configured to recognize, take into account and / or compensate for measurement tolerances that vary over time. In the case of measurements of parameters, for example of current, voltage and / or temperature, and in particular of a resistance, the measurement tolerance or an error of the measurement can vary over time and / or depending on the parameters. A simple example would be a changed temperature, which has an effect, for example, on the resistance of a conductor. This can be difficult to estimate in advance, in particular in the case of more complex circuits which have not yet been tested for a relatively long period of time (such as months or years, for example). For example, this may be particularly severe in newly developed circuits and / or components. In this case, it is advantageously possible according to the invention to achieve predictive maintenance, which in particular reduces costs and / or offers time saving. Furthermore, the downtime can be reduced. For example, it is conceivable that a circuit and / or a vehicle, e.g. an autonomous vehicle, is subjected to maintenance and / or repair outside the operating time (e.g. at night) if an analysis of the deviation makes this necessary and / or recommended in a predictive manner. Moreover, a longer or continuous availability of the circuit can be ensured, which saves costs and / or time in particular. This can also reduce and / or prevent downtime, in particular at a time at which the circuit and / or the vehicle are required (e.g. during a taxi or bus during the day). Moreover, more robust and / or more early fault response strategies may be enabled. Furthermore, long-term findings about the circuit, in particular about electronic trip units (e.g. eUSE), can be collected, evaluated and / or used, for example in order to optimize the circuit and / or the electronic trip unit. This makes it possible to provide even more precise predictive maintenance.The measuring can comprise a detection of a parameter. In the simplest case, current and / or voltage can be measured. In this case, the measurement can be carried out by a measuring device and / or a computing unit. Preferably, the monitoring of at least one or all current paths and a current path diagnosis can thus take place. In this case, the measuring device can be connected to the computing unit for data communication via a data connection. The measuring device can send the at least one (measured) parameter to the computing unit. The computing unit can control and / or regulate the measuring device via a data connection.All steps can be carried out by a computing unit, in particular the measurement, detection, calculation, determination, analysis and / or output. Alternatively or additionally, these steps can also be carried out by a (local) control device, a further (local) control device (or control device clusters) and / or an external computing cluster. An external computing cluster can comprise a cloud and / or high-performance computing unit, which is connected to the circuit and / or computing unit, for example, via a data connection. In this case, this can be carried out locally and / or in the external computing cluster, for example, depending on the outlay. This can be made dependent on the necessary memory and / or the computing capacity.The circuit can preferably be an electrical circuit whose components are electrically connected by lines.The at least one measurement position can lie on a line and / or on or in one of the devices, e.g. control device(s). The at least one measurement position, in particular all measurement positions, can be connected to the measurement device and / or the computing unit via a measurement connection.The computing unit can be connected to the control unit, wherein in particular the computing unit is configured separately from the control unit in order to advantageously enable facilitated maintenance or exchange, redundancy and / or subsequent integration into an existing system. It can also be provided that the control unit comprises the computing unit, wherein the computing unit forms an additional computing unit within the control unit, whereby a separate and / or more efficient calculation is advantageously made possible. In this case, the control device, the control devices and / or the arithmetic unit can be connected to an energy supply, in particular a battery.The calculation, in particular by the arithmetic unit, of at least one actual value based on the at least one parameter can use the at least one parameter as an input. Two or more parameters may also be used. For example, (measured) current and a (measured) voltage can be used, and, in particular taking into account a measured temperature (and / or further measured parameters), an actual value, for example a resistance, can be calculated. It can furthermore be provided to take at least one of the following parameters into account:a line lengtha conduit cross sectioncoefficients of line heatingcable parameters (e.g. material, coefficient of thermal expansion, maximum temperature resistance)The determination, in particular by the computing unit and / or an external computing cluster, can provide a deviation of the at least one actual value from a setpoint value.The detection can in this case comprise in particular signal processing, for example analog-to-digital conversion (ADC). The measured values, the converted values, the actual values, the target values, the measurement tolerances, the deviations, the analysis and / or the analysis results can be stored, for example, in a non-volatile computer-readable storage medium which is connected to the computing unit, the control unit and / or the measuring device.In this case, the setpoint value can represent a desired or expected value, which occurs in particular under certain circumstances, conditions and / or (imposed) parameters. For example, it can be provided that a setpoint value of 5V is to be measured at a current of 10 mA and 25° C. An actual value of 6 V (under otherwise identical conditions) could indicate, for example, an excessive voltage, wherein the deviation here is, for example, 1 V. However, this can preferably be made dependent on whether the measurement tolerance here is less than 1V. If, for example, the measurement tolerance is 2 V under corresponding conditions, it can be established within the scope of the analysis that the deviation lies within the measurement tolerance, and therefore no action (such as maintenance) is necessary, in particular as an analysis result.The circuit can have a housing, in particular a one-piece or multi-piece housing, which surrounds the circuit at least partially and advantageously protects it.Within the scope of the invention, it can be advantageous that the circuit has at least one electronic triggering unit and / or at least one control device, wherein the at least one parameter comprises:a voltage and / or a current, which characterizes in particular at least one current path of the electronic trip unit,a voltage and / or a current of the at least one control unit, in particular at an output of the control unit, and / ora temperature at at least one measurement position of the circuit, in particular at the input and / or output of the electronic trip unit.The circuit can have at least one electronic trip unit (eUSE). The circuit particularly preferably has exactly one electronic trip unit. This can provide sufficient protection and in particular simultaneously enable the implementation of the present method. The at least one measurement position is preferably arranged close to or on the at least one electronic triggering unit. In other words, the electronic trip unit can be used as an abstract current and / or voltage sensor during measurement, whereby it can be used advantageously both for safeguarding and for monitoring without further components being necessary.Alternatively or additionally, further parameters can be included, in particular temperature, (air) humidity, inclination and / or (movement) speed. These can be measured, for example, via corresponding sensors, preferably at measurement points.In addition, at least one control unit can be provided, which is connected to the electronic trip unit. The electronic triggering unit can also be arranged within the control unit. It can be provided that the electronic trip unit protects the control device, for example from overload, such as voltage peaks and / or increased currents. Furthermore, at least one further or more control units can be provided. At least two control units can form a control unit cluster. In this case, a plurality of control units can be connected by corresponding lines. The at least one measurement position can be arranged in, on and / or between the control device or the control devices. Particularly preferably, at least one measurement position is located close to the electrical triggering unit. Preferably, a measurement position is arranged here, in particular directly, before and / or, in particular directly, after the electronic triggering unit. In this way, the deviations can be detected particularly efficiently. Alternatively or additionally, the at least one measurement position can be located at, or in particular close to, a connection of the circuit, for example of the at least one control unit. This allows measurement at any time and / or nevertheless a compact construction. In addition, a line between the at least one control device and further components can thus be detected completely. Preferably, the at least one measurement position is arranged on an output channel or on all output channels of the at least one control unit and / or all control units. As a result, a fully comprehensive monitoring can take place through a plurality of measurement positions. Additionally or alternatively, it is conceivable that a measurement position is located at at least one supply input of the at least one control unit. Since fluctuations can occur there, which occur, for example, as a result of changing loading of the control unit, a change can be detected particularly efficiently here.By automatically and / or forcibly switching the electronic trip unit, different switching states can be realized. This can be used to carry out a measurement and / or the further method steps in each case. Thus, different information may be collected to characterize the circuit and preferably allow analysis of a deviation.The invention can allow an analysis of the current paths on an electronic trip unit, in particular despite (negatively) influencing external influences, such as mass offsets and / or temperature dependence(s), which cause (variable) measurement tolerances, for example.Within the scope of the invention, it is conceivable that the at least one actual value has an actual resistance and the target value has a target resistance and / or wherein the analysis of the deviation is carried out based on the deviation and / or an, in particular variable, measurement tolerance.For example, an actual or setpoint parameter, in particular an actual or setpoint resistance, can be calculated based on voltage and / or current. In the simplest case, the resistance can be determined, at least in sections (based on the line), via the quotient of voltage and current. It can also be provided to calculate an estimate of the actual or desired parameter on the basis of one of these parameters and / or other parameters. Alternatively or additionally, further parameters can be included, in particular temperature, pressure, force effect, (air) humidity, inclination and / or (movement) speed. These can be measured, for example, via corresponding sensors, preferably at measurement points. This enables an even more accurate calculation of the actual value and / or target value.In this case, it can be provided that the measurement of parameters is, in particular in principle, not subject to exact but to a measurement tolerance (in particular measurement error), which is in particular variable. Particularly preferably, such a variable measurement tolerance is taken into account within the scope of the method. For example, the measurement tolerance can be dependent on the at least one parameter and / or imposed parameters. During the calculation, the (current) measurement tolerance can preferably be calculated alternatively or additionally, preferably based on the at least one parameter. Particularly preferably, all parameters determined during the measurement (and acquisition) are taken into account.It can be provided within the scope of the invention that a learning method is carried out before the measurement, in particular during startup, in particular comprising at least one, preferably all, of the following steps:measuring the at least one parameter at at least one measurement position, wherein the at least one measurement position is located at or in the circuit,detecting the at least one parameter,calculating at least one actual value based on the at least one parameter,defining the setpoint value and / or a measurement tolerance based on the actual value.In this case, during the setting, an (initial) measurement tolerance can also be set based on the actual value and / or the setpoint value. The learning method is particularly preferably used to adapt the measurement tolerance. Furthermore, the setpoint value can be established on the basis of the actual value and / or the measurement tolerance.Preferably, in the context of the method, the learning method is carried out repeatedly. In this case, the learning method can be carried out initiatively at the beginning, for example in the context of assembly. During (later) operation, the learning method can be used for readjustment.The method and / or in particular the learning method can be computer-implemented, for example by the (above-mentioned units) arithmetic unit, control device and / or external arithmetic clusters. Furthermore, artificial intelligence can be used here, in particular in order to enable improved pattern recognition, for example with respect to the shape and / or configuration of the envelope curve.In this case, the measurement can be carried out by a measuring device (see above) and / or a computing unit. It can be provided that the remaining steps are carried out by the computing unit, in particular the acquisition, calculation and / or definition.Initially, a learning method may be performed to determine, particularly in a vehicle, the characteristics of the respective lines. In this case, the at least one parameter can be determined at at least one measurement position, preferably at at least two measurement positions.In this case, an (initial and / or updated) measurement tolerance can be determined by repeated measurement. For example, it can be assumed that a circuit in which the individual components have passed all tests is functional. Repeated measurement under certain, preferably identical, conditions, such as imposed parameters, can then give different results. The range of variation of these results can thus result in the measurement tolerance for these same conditions. It can be provided here to "pass through" different conditions, in particular by different combinations of imposed parameters, wherein in particular the corresponding measurement tolerance is respectively established, for example initially. It can be provided that these are adjusted individually or additionally, in particular in a readjustment period. It can be particularly preferably determined later more precisely and / or reliably whether a deviation is due to actual changes in the circuit and / or a component, such as a control unit, a line and / or an electronic trip unit, or whether in particular a supposedly too large deviation is due instead to changed measurement tolerance. Particularly preferably, the above-mentioned advantages according to the invention can be realized thereby.It is furthermore conceivable that the learning method comprises an embossing and / or, in particular, subsequent measuring of at least one of the following embossed parameters:a voltage and / or a current, which characterizes in particular at least one current path of the electronic trip unit,a voltage and / or a current of the at least one control unit, in particular at an output of the control unit, and / ora temperature at at least one measurement position of the circuit, in particular at the input and / or output of the electronic trip unit, wherein preferably at least one, preferably a plurality of, impressed parameters are impressed in and / or on the circuit and, in particular subsequently and / or synchronously, a measurement is carried out in order in particular to determine a plurality of actual values and, based thereon, to obtain a plurality of (initial) setpoint values and / or measurement tolerances.In this case, it can be provided that the steps of the learning method, in particular with the same designation, correspond to substantially identical procedures according to the method. For example, the measurement within the scope of the learning method can correspond to the (regular) measurement during operation or can be substantially identical.It can be provided here to measure and / or apply a voltage between at least two measurement points.In this case, the parameters imposed, in particular in addition to current, voltage and / or temperature, can likewise comprise:imposing (or suspending) force action, in particular due to force impacts and / or periodic movements (e.g. shaking)embossing (or exposing) reduced and / or increased air pressure (in particular compared to the atmosphere)embossing (or suspending) rotation, inclination and / or torsion, in particular repeated rotation,removing components from the circuit and / or connecting (further) components.In this case, an impressed parameter can be impressed at a measurement position (at which measurement can also take place in particular) or at a separate impressed position, which can advantageously be more easily reached and / or can be positioned in a cost-saving manner (e.g. on a housing, in particular from the outside). An impressed parameter can be simulated by impressed the parameter at a specific impressed position. For example, a force effect can be applied close to a suspension of the circuit in order to simulate a release of a fastening of the circuit. The effect on the parameters, in particular during the measurement and the further above method steps, can subsequently be determined by the learning method. Thus, improved (predictive) maintenance and / or diagnosis is possible later, for example (based on the above example) similar force actions which cause corresponding measurement of actual values, which can now be attributed to an actual detachment of a fastening.In this case, it can be provided that, in the case of one, in particular each, application of a specific combination of parameters, a (described above) measurement, detection, calculation and / or definition takes place. As a result, a desired value and / or a measurement tolerance can be determined in each case for different combinations of parameters. This may be advantageous because later, in particular during operation, this combination of parameters may potentially only be partially imposed, e.g. because a part of the circuit is defective or an imposed is not possible (e.g. the intentional suspension of impacts). Because a specific combination is not possible and / or a deviation between the actual and the desired value is determined, it can be made possible to detect defective parts of the circuit as accurately as possible. As a result, these can be changed in a targeted manner.It is also conceivable that in the learning method a spectrum analysis is carried out, comprising an impression of a plurality of frequencies, in particular for voltage and / or current, at at least one measurement position, wherein in particular the measurement, detection, calculation and / or fixing is carried out continuously in order to determine a plurality of (initial) target values and / or measurement tolerances, which are used to form an initial envelope curve. Here, the stamping can alternatively or additionally comprise a measurement of current and / or voltage, wherein in particular generated frequencies, e.g. ripple frequencies, which are generated by the load, can be measured.Particularly preferably, the (initial) envelope curve is determined by reference values and measurement tolerances. In this case, each setpoint value can be assigned a measurement tolerance. A measurement tolerance can preferably have a deviation or tolerance in at least one direction, preferably in both directions, wherein in particular one direction has larger values or smaller values. It is in particular conceivable that the measurement tolerance is symmetrical (the same in both directions) or asymmetrical (different in the directions upwards and downwards). The accurate determination of the measurement tolerance within the scope of the invention can thereby enable a particularly reliable and / or accurate analysis.An envelope curve can represent the profile of the setpoint values and / or measurement tolerances, for example within the scope of an enveloping curve. For example, a setpoint value can be represented, wherein the measurement tolerance surrounds the setpoint value as a fault bar or fault cloud. The envelope curve can run on both sides, in particular above and below the setpoint values, in order to take into account, in particular, an asymmetric distribution of the measurement tolerance. A one- or multi-dimensional stringing together of setpoint values with corresponding measurement tolerances can then be surrounded by an envelope curve (or envelope cloud). The comparison between different envelopes, preferably comprising substantially identical (impressed) parameters, can then be used to perform an analysis. In this case, it is preferably possible to perform comparisons between actual and target values taking account of measurement tolerances. Alternatively or additionally, the shape and / or the course of the envelope curve can preferably also allow conclusions about the cause, which would in particular not otherwise be recognizable. For example, a specific fault, e.g. a short circuit or an interrupted line, can lead to very specific changes in the actual values, measurement tolerances and / or, preferably, the envelope curve. For example, the envelope curve can also be used to detect minor changes, which would not be recognizable in particular when using only one actual and / or setpoint value. For example, a creeping change, in particular an increase in the resistance, caused in particular by a ground shift, can be detected better and / or more reliably by using the envelope curve.Preferably, the embossing takes place within the scope of the spectrum analysis at at least two or a plurality of measurement positions and / or embossing positions. Particularly preferably, at least one measuring position and / or embossing position can be arranged between two components of the circuit.An envelope curve can have at least one, in particular initial, setpoint value. In the case of a plurality of parameters and / or a plurality of actual and / or target values, the target value or the target values and / or the envelope curve can be successively readjusted.An envelope curve can thus be determined for the spectrum of the parameter change, in particular voltage changes, in the (initial) standard state. Then, in particular later in the context of the method, a continuous spectrum analysis or a measurement of the (current) envelope curve can be carried out in order to achieve a comparison and in particular to check the functionality.Deviations or errors can be reliably determined or predicted by the actual values, setpoint values, measurement tolerances and / or envelope curve, and can preferably be differentiated from erroneous detections or measurement tolerances.The variation of the frequencies can serve to detect a changed frequency response, for example, due to aging processes. Certain aging processes and / or defects can preferably have a specific effect on the frequency response and advantageously be determined in the context of spectrum analysis. A simple example would be the change in frequency response in a coaxial cable, for example, if a dielectric is damaged.Within the scope of the invention, it is optionally possible that the learning method is continued, in particular after an initial startup, preferably during the operation of the circuit, over a readjustment period, in particular in order to take account of a change in setpoint values and / or measurement tolerances occurring over time during the measurement, and based thereon to adapt the setpoint values, the measurement tolerances and / or the initial envelope curve in order to obtain updated setpoint values, updated measurement tolerances and / or an updated envelope curve.A readjustment period can comprise 12 months, in particular 6 months, preferably 4 months, particularly preferably 3 months, ideally 2 months, advantageously 4 weeks.In this case, a readjustment period can be established at the factory.In this case, a duration of the readjustment period can be adapted and / or extended. This can be established via at least one property of the actual value, the setpoint value, the measurement tolerance and / or the envelope curve. For example, an absent change (e.g. readjustment), in particular under substantially identical (impressed) parameters, can indicate that a further adaptation is not necessary.Deviations of the actual value from a setpoint value outside a corresponding measurement tolerance, preferably after termination of the readjustment period, can preferably be recognized as an aging phenomenon and / or defect.Within the scope of the invention, a setpoint value can also mean a plurality of setpoint values if a plurality of actual values and / or parameters are used. Each actual value or setpoint value can preferably have a measurement tolerance.It can be provided here that the readjustment period and / or the learning method is at least partially restarted, in particular with respect to corresponding parameters, when a specific component has been replaced. This advantageously allows particularly good adaptation to a modified circuit in order to realize the advantages according to the invention.In the readjustment period, spectrum analysis can preferably be carried out repeatedly.Furthermore, it can be provided within the scope of the invention that the learning method is continued during the operation of the circuit, in particular after an initial startup, whereby an updated setpoint value, updated measurement tolerances and / or an updated envelope curve are determined, in particular continuously, wherein this is carried out on the basis of at least one of the following criteria:receiving at least one updated setpoint value, an updated measurement tolerance and / or an updated envelope curve, in particular via a data connection,setting an updated setpoint value, an updated measurement tolerance and / or an updated envelope curve based on the reception and / or by user input.In this case, the user input can be effected by a driver and / or as part of maintenance.In this case, advantageously, more short-term, medium-term and / or long-term deviations can be detected and / or differentiated. In this case, provision can be made (as described above) for the parameters to be measured and / or impressed again. On account of the performance of substantially identical measurements, it is thereby possible to determine how one or more measurement tolerances change.In this case, it can be provided that, in particular in the case of readjustment, a comparison takes place from this point in time with a readjusted setpoint value and / or a readjusted envelope curve. This can be advantageous, for example, if certain measurement tolerances, e.g., during aging, are changed subsequently. This can also be advantageous in order to implement an emergency operating program, wherein a deviation is initially detected, in particular outside the measurement tolerance, but a functionality of the circuit can be ensured at least temporarily, for example as long as no workshop is still being sought. In this case, it can be provided that a countermeasure, for example an emergency stop and / or a more stringent warning, is issued if a renewed deviation is detected, in particular on the basis of a readjusted setpoint value and / or a readjusted envelope curve.In this case, it can be provided that the method, in particular the reception via the data connection, comprises the reception of information of another circuit, preferably of identical construction, as a result of which, in particular, empirical values of other circuits, which have been used for example longer, differently and / or more intensively, can be used. In this case, the circuit can be connected to a data connection which transmits and / or receives corresponding data, for example via a LAN, WLAN; Bluetooth, mobile radio and / or Internet connection.With respect to the present invention, it is conceivable that the determination of a deviation comprises at least one of the following steps:calculating the difference between at least one actual value and a, in particular corresponding, setpoint value and / or updated setpoint value,comparing the initial envelope or updated envelope and the current envelope, wherein in particular a difference between the initial envelope or updated envelope and the current envelope is calculated.In this case, the difference between all actual values can be calculated using corresponding setpoint values. Preferably, the amount of the difference is determined within the scope of the calculation, in particular in order to establish the absolute deviation. This can be decisive for the urgency of an intervention, for example the visit to a workshop. In addition, the sign can be determined, in particular in order to confine or establish the cause. For example, the absence of a voltage may indicate an interruption. This allows a more accurate determination of the source of error.In this case, the current envelope curve can be determined by measuring (as described above), in particular by embossing the essentially identical parameters which have been embossed. The current envelope curve can be determined in particular by measuring during operation, for example as part of a check while the vehicle is running. The difference of the envelope curves can be related to the individual actual values and corresponding desired values. Alternatively or additionally, it can also be provided to use the envelopes or the envelope surfaces and to determine differences between the surfaces. Within the scope of pattern recognition, certain deviations can be determined and in particular compared with historical data, in order to enable, for example, an improved determination as to whether or not a deviation lies within a measurement tolerance, and / or an improved determination of the cause.The determination can be carried out alternatively or additionally based on information from at least one other system, vehicle and / or an entire fleet of vehicles. This can be effected, for example, via a data connection, in particular the Internet and / or a cloud. For example, actual values and / or desired values can thereby be provided. A deviation can thereby potentially be detected earlier and / or more reliably. For example, a strong change, which has caused problems elsewhere according to experience, can thereby be detected earlier, in particular compared to a case in which no replacement takes place.It is furthermore conceivable that the analysis determines whether a deviation lies within the measurement tolerance and / or updated measurement tolerance, and is therefore in particular permissible or not permissible, and / or that the analysis based on the deviation comprises a determination of the cause of the deviation, and / or wherein in particular the analysis result is output to a user, wherein the analysis result comprises a summary of the analysis, a classification of the analysis and / or a recommendation for action.The difference can be compared with the (updated) measurement tolerance. If the difference lies within the measurement tolerance or the measurement tolerance is greater, it can be concluded from this that the deviation is "permissible" or "normal", in particular that this is not attributable to an error and / or aging process. If the difference is greater than the measurement tolerance, in particular at least 20% greater, for example 40% greater, preferably 60% greater, particularly preferably 80% greater, it can be concluded that the deviation is "impermissible", in particular that this is attributable to an error, defect and / or an (excessive) aging process. In this case, a determination of the cause can result in a component being defective, a short circuit being present, an interruption being present, a cable fire and / or a deficient (and possibly hazardous) electrical connection being present. This can be output, in particular, as an analysis result.In this case, the measurement tolerance and / or setpoint values can be set at the factory, in particular initially. These can be adjusted, in particular continuously, within the scope of the learning method, in particular in order to be able to take account of changes in the (imposed) parameters such as aging processes, for example.It can be particularly preferred if the analysis comprises a comparison of the deviation and / or measurement tolerance with a historical deviation and / or historical measurement tolerance. Current and / or historical (or past) deviations and / or measurement tolerances can be stored, for example, in a non-transitory computer-readable storage medium, in particular the computing unit, the external computing cluster and / or the control unit. In this case, a time period can be taken into account in particular over which the deviation and / or the measurement tolerances occur. A distinction can be made between the following categories:the deviation has a short-term deviation; in particular, this short-term deviation is attributable to temporarily restricted influences, such as a particularly high temperature at at least one measurement position. An example would be a short-term deviation of extremely high external temperatures of, for example, 48° C. In this case, a short-term deviation can comprise the last 48 hours, in particular the last 24 hours, preferably the last hour, particularly preferably the last minute, ideally the last 20 seconds.the deviation has a medium-term deviation, in particular this medium-term deviation is attributable to temporarily restricted but repeated influences, such as a comparatively high temperature at at least one measurement position. A simple example can be a vacation trip to a particularly warm location, where for example an average temperature of 45° C. prevails. A medium-term deviation may comprise the last 4 months, in particular the last 2 months, preferably the last month, particularly preferably the last 3 weeks, ideally the last 2 weeks, advantageously the last week.the deviation has a long-term deviation, in particular this long-term deviation is attributable to temporarily non-restricted influences, such as, for example, a geometric deformation of at least part of the circuit, an at least partial oxidation, an electrical interruption and / or a short circuit. A long-term deviation can comprise the last 36 months, in particular the last 24 months, preferably the last 12 months, particularly preferably the last 6 months, ideally the last 4 months, advantageously the last 2 months. wherein the output result preferably comprises, depending on the category, the category, a recommendation for action and / or a fault diagnosis, wherein the output result is preferably output acoustically and / or visually.Particularly preferably, short-term and / or medium-term deviations can be calculated locally, in particular by the computing unit, the control unit and / or the measuring device. Particularly preferably, medium-term and / or long-term deviations can be calculated externally, in particular from the external computing cluster. In this way, a simpler and / or more data-efficient provision of the data for other items of information and a simpler and / or more data-efficient consideration of other information (e.g. of other identically constructed circuits) can be effected.In this case, it can be provided to determine deviations, for example absolute deviations in absolute value, of the actual parameter from the setpoint parameter of 0.0001 to 10000%, in particular of 0.001 to 1000%, preferably of 0.01 to 100%, particularly preferably of 0.1 to 10%. For example, a deviation of at least 10 ohms, in particular of 1 ohm, preferably of 0.1 ohm, particularly preferably of 0.01 ohm, ideally of up to 0.004 ohm, can preferably be established. As a result, even minor deviations in comparatively complex circuits, such as in vehicles, can be detected.It is also conceivable for the user to be asked to take position to changed parameters, for example via a display which is advantageously also used for output. For example, an elevated temperature that is continued over several days could indicate a travel of the vacation into a particularly warm country. However, should there be any doubt about the analysis, certain errors can be eliminated thereby. The user can thereby enter corresponding (prevailing parameters), for example via an input device. Thereby, misdiagnoses can be prevented.In this case, an action recommendation can comprise the soon stopping, immediate stopping and / or searching of a workshop. As a result, a user, in particular a driver, can be warned.A fault diagnosis can comprise the specific explanation for the reason of the deviation, for example a defect of the electronic trip unit, of the control unit and / or of a line. For example, a current flow, which is in particular repeatedly, unmeasurable at the input of a component can mean an interruption. This allows improved maintenance and / or simplified fault finding, whereby costs and / or material can be advantageously saved.The output result can be output acoustically, for example by a loudspeaker, earphones and / or a mobile terminal such as a mobile telephone and / or a clock. Alternatively or additionally, the output result can be output visually, for example (in particular in the case of a vehicle) via a screen, a head-up display, an operator console, a screen of a mobile terminal such as a mobile telephone and / or a clock.In this case, outputting can alternatively or additionally also comprise transmitting via a data connection. As a result, the deviation and / or the analysis result can also be made available to other circuits, arithmetic units, control units and / or vehicles. This can make it possible to also use corresponding external information and / or to generate statistics about failures, defects, repairs, maintenance, aging processes, classification and / or action recommendations. This makes it possible to provide even more precise predictive maintenance. This also allows the downtime to be minimized.The above object is furthermore achieved according to a second aspect by a computing unit according to the invention, comprising means for carrying out the method according to one of the preceding claims.The above object is further achieved according to a third aspect by a measuring device for measuring control of a circuit, wherein the measuring device is configured to perform a substantially time-synchronous measurement of the at least one parameter, and in particular to implement the method according to the first aspect.In this case, it can be provided that the measuring device is configured to measure at least two, preferably a plurality of, parameters.The measuring device can have a computing unit, in particular a computing unit according to the invention. This allows a particularly compact and / or cost-effective construction.A device can also be provided, in particular comprising a circuit which is configured to implement the method according to the first aspect.The above object is furthermore achieved according to a fourth aspect by a computer program product according to the invention, comprising instructions executable by a computing unit which, when the program is executed by a computing unit, cause the computing unit to implement the method according to the first aspect.The above object is furthermore achieved according to a fifth aspect by a non-transitory computer-readable storage medium according to the invention comprising a computer program product according to the fourth aspect.The above object is furthermore achieved by a vehicle according to the invention, comprising at least one non-transitory computer-readable storage medium according to the fifth aspect.Further advantages, features and details of the invention will become apparent from the following description, in which a plurality of exemplary embodiments of the invention are described in detail with reference to the drawings. The features mentioned in the claims and in the description can be essential to the invention individually or in any combination.The invention is shown schematically in each case in the following figures: FIG. 1 shows circuit 1, FIG. 2 method 100, FIG. 3 shows method 100, FIG. 4 shows method 100, FIG. 5 shows learning methods 200, FIG. 6 shows learning methods 200 and FIG. 7 shows method 100.FIG. 1 shows a circuit 1 which has a control unit 11 and, in the present case, a further control unit 12. These may together form a control unit cluster. The circuit may include a power supply 60, for example a battery 60. The components of the circuit 1 can be connected via lines 2. The control unit 11 has a computing unit 20 comprising means 21, which are designed in particular for carrying out the method 100. Furthermore, the computing unit 20 can be connected to a storage medium 40 or can have it. The storage medium comprises a computer program 50. At one or more measurement positions 3, parameters such as voltage U, current I and / or temperature T can be impressed and / or measured. In this case, the circuit 1 or the control device 11 can have an electronic trip unit 10.FIG. 2 shows, by way of example, a method 100 comprising the steps:measuring 110 at least one parameter I, U, Tdetecting 120 the parametercalculating 130 an actual valuedetermining 140 a deviationanalysis 150 of the deviationoutputting 160 an analysis resultFIG. 3 shows further details of method 100 by way of example, wherein an actual value is calculated 130 on the basis of the at least one parameter I, U, T. In this case, for example, a resistance can be calculated from current and voltage, taking into account, for example, the temperature. The determination 140 of a deviation 142 of the at least one actual value from a setpoint value 141 or updated setpoint value 144 can furthermore be carried out in order to obtain a deviation 142, which can be based, for example, on a difference 143 between the setpoint value and the actual value.FIG. 4 shows further details of method 100 by way of example, wherein analysis 150 may be based on deviation 142. In addition, the (initial) measurement tolerance 145 and / or updated measurement tolerance 146 can also be taken into account in this case. An analysis result 160 can be output in the last step.FIG. 5 shows, by way of example, a learning method 200 comprising the steps:measuring 210 the at least one parameter (I, U, T),detecting 220 the at least one parameter (I, U, T),calculating 230 at least one actual value,defining 240 the setpoint value and / or a measurement tolerance.FIG. 6 shows, by way of example, a learning method 200 comprising an impression of impressed parameters I, U, T. In this case, a spectrum analysis 206 can be carried out. This can be carried out repeatedly, in particular within a readjustment period, which can be used to adapt setpoint values and / or measurement tolerances.FIG. 7 shows, by way of example, a method 100 in which a current envelope 209 is compared with an initial envelope 207 and / or an updated envelope 208. The initial envelope 207 is preferably readjusted within the scope of a learning method 200, which can be connected upstream in particular as part of the method 100, in order to obtain an updated envelope. As a result, setpoint values, the envelope curve and / or measurement tolerances can be readjusted.List of reference characters1 Circuit 2 Line 3 Measurement position I Parameter / measurement position for current U Parameter / measurement position for voltage T Parameter / measurement position for temperature 10 Electronic trip unit 11 Control device 12 Further control device 20 Computing unit 21 Means 40 Storage medium 50 Computer program product 60 Energy supply, Battery 100 Method 110 Measuring at least one parameter 120 Detecting the parameter 130 Calculating an actual value 131 Actual value 140 Determining a deviation 141 Target value 142 Deviation 143 Difference 144 Updated target value 145 Measurement tolerance 146 Updated measurement tolerance 150 Analysis of the deviation 160 Output of an analysis result 200 Learning method 205 Imposing on impressed parameter (I, U, T) 206 Spectrum analysis 207 Initial envelope 208 Updated envelope 209 Actual envelope 210 Measuring the at least one parameter (I, U, t) 220 Detection of the at least one parameter (I, U, T) 230 Calculation of at least one actual value 240, Determination of the setpoint value and / or a measurement tolerance

Claims

Method (100) for monitoring a circuit (1), in particular in order to enable predictive maintenance, wherein the method (100) comprises the following steps: - measuring (110) at least one parameter (I, U, T) at at least one measurement position (3), wherein the at least one measurement position (3) is located at or in the circuit (1), - detecting (120) the at least one parameter (I, U, T), - calculating (130) at least one actual value (131) based on the at least one parameter (I, U, T), - determining (140) a deviation (142) of the at least one actual value (131) from a target value (141), - analyzing (150) the deviation (142), and outputting (160) an analysis result (161) based on the analysis (150).Method according to one of the preceding claims, characterized in that the circuit (1) has at least one electronic trip unit (10) and / or at least one control unit (11), wherein the at least one parameter (I, U, T) comprises: - a voltage (U) and / or a current (I) which characterizes in particular at least one current path of the electronic trip unit (10), - a voltage (U) and / or a current (I) of the at least one control unit (11), in particular at an output of the control unit (11), and / or - a temperature (T) at at least one measurement position (3) of the circuit (1), in particular at the input and / or output of the electronic trip unit (10).Method according to one of the preceding claims, characterized in that the at least one actual value has an actual resistance and the setpoint value has a setpoint resistance, and / or wherein the analysis (150) of the deviation is carried out on the basis of the deviation (142) and / or an, in particular variable, measurement tolerance (145).Method according to one of the preceding claims, characterized in that a learning method (200) is carried out before the measuring, in particular during a startup, comprising at least one of the following steps: - measuring (210) the at least one parameter (I, U, T) at the at least one measurement position (3), wherein the at least one measurement position is located at or in the circuit, - detecting (220) the at least one parameter (I, U, T), - calculating (230) at least one actual value based on the at least one parameter (I, U, T), - defining (240) the target value and / or a measurement tolerance (145) based on the actual value.Method according to Claim 4, characterized in that the learning method comprises an application (205) and / or, in particular subsequent, measurement (210) of at least one of the following applied parameters (I, U, T): - a voltage (U) and / or a current (I) which characterizes in particular at least one current path of the electronic trip unit (10), - a voltage (U) and / or a current (I) of the at least one control unit (11), in particular at an output of the control unit (11), and / or - a temperature (T) at at least one measurement position (3) of the circuit (1), in particular at the input and / or output of the electronic trip unit (10), wherein preferably at least one, preferably a plurality of, applied parameters (I, U, are applied, t) in and / or on the circuit ( 1) and, in particular subsequently and / or substantially synchronously in time, a measurement ( 210) is carried out in order in particular to determine a plurality of actual values and, based thereon, to obtain a plurality of setpoint values ( 141) and / or measurement tolerances ( 145).Method according to one of the preceding claims 4 or 5da characterized in that in the learning method (200) a spectrum analysis (206) is carried out, comprising an impression (205) of a plurality of frequencies, in particular for voltage and / or current, at at least one measurement position (3), wherein in particular the measurement (210), detection (220), calculation (230) and / or fixing (240) is carried out continuously in order to determine a plurality of setpoint values (141) and / or measurement tolerances (145) which are used for forming an initial envelope curve (207).Method according to one of Claims 4 to 6, characterized in that the learning method (200), in particular after initial startup, is continued preferably during the operation of the circuit (1), over a readjustment period, in particular in order to take account of a change in setpoint values (141) and / or measurement tolerances (145) occurring over time during the measurement (110, 210), and based thereon to adapt the setpoint values (141), the measurement tolerances (145) and / or the initial envelope curve (207) in order to obtain updated setpoint values (144), updated measurement tolerances (146) and / or an updated envelope curve (208).Method according to one of the preceding claims 4 to 7, characterized in that the learning method (200) is continued, in particular after an initial startup, during the operation of the circuit (1), whereby updated setpoint values (144), updated measurement tolerances (146) and / or an updated envelope curve (208) are determined, in particular continuously, wherein this takes place on the basis of at least one of the following criteria: - reception of at least one updated setpoint value (144), an updated measurement tolerance (146) and / or an updated envelope curve (208), in particular via a data connection, - setting of an updated setpoint value (144), an updated measurement tolerance (146) and / or an updated envelope curve (208) on the basis of the reception and / or by a user input.Method according to one of the preceding claims, characterized in that the determination (140) of a deviation (142) has at least one of the following steps: - calculation of the difference (143) between at least one actual value (131) and a setpoint value (141) and / or updated setpoint value (144), - comparison between the initial envelope (207) or updated envelope (208) and a current envelope (209), wherein in particular a difference (143) between the initial envelope (207) or updated envelope (208) and the current envelope (209) is calculated.Method according to one of the preceding claims, characterized in that the analysis (150) determines whether a deviation lies within the measurement tolerance and / or updated measurement tolerance, and is therefore in particular permissible or not permissible, and / or in that the analysis (150) comprises a determination of the cause of the deviation (142) on the basis of the deviation (142), and / or wherein in particular the outputting (160) of the analysis result (161) to a user takes place, wherein the analysis result (161) comprises a summary of the analysis (150), a classification of the analysis (150) and / or a recommendation for action.Computing unit (20) comprising means (21) for carrying out the method (100) according to one of the preceding claims.A measuring device (10) for measuring control of a circuit, wherein the measuring device (10) is adapted to perform a substantially time synchronous measurement of the at least one parameter (I, U, T), and in particular to implement the method according to any of claims 1 to 10.A computer program product (50) comprising instructions executable by a computing unit (20) which, when the program is executed by a computing unit (20), cause the computing unit (20) to implement the method (100) of any one of claims 1 to 10.A non-transitory computer readable storage medium (40) comprising a computer program product (50) according to the preceding claim.A vehicle comprising at least one non-transitory computer readable storage medium (40) according to the preceding claim.

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