WO2020148344A1

WO2020148344A1 - Method and arrangement for determining the electromagnetic compatibility (emc) of a technical system

Info

Publication number: WO2020148344A1
Application number: PCT/EP2020/050930
Authority: WO
Inventors: Oussama SASSI
Original assignee: Volkswagen Aktiengesellschaft
Priority date: 2019-01-18
Filing date: 2020-01-15
Publication date: 2020-07-23
Also published as: CN113272664A; DE102019202978A1; EP3911962A1

Abstract

The invention relates to a method for determining the electromagnetic compatibility (EMC) of a technical system, comprising: - specifying at least one influencing variable of the technical system, wherein the influencing variable has a potential influence on the EMC of the technical system; - determining at least one EMC outcome variable of the technical system on the basis of a variation of the influencing variable. The invention further relates to an arrangement (200) for determining the electromagnetic compatibility (EMC) of a technical system, comprising: - an input device (210) by means of which a user can specify at least one influencing variable of the technical system, wherein the influencing variable has a potential influence on the EMC of the technical system; - a computing device (220) which is designed to determine at least one EMC outcome variable of the technical system on the basis of a variation of the influencing variable.

Description

description

Method and arrangement for determining the electromagnetic compatibility (EMC) of a technical system

Electromagnetic compatibility (EMC) relates to the ability of technical systems not to interfere with other systems through self-generated electrical or electromagnetic effects or with other devices.

Due to customer requirements and the laws for safety and quality, technical systems and in particular vehicles (in the context of the present disclosure in particular motor vehicles and furthermore in particular passenger cars) have become increasingly complex. In particular, the number of electrical and electronic components has increased. This places corresponding demands on the review of the

electromagnetic compatibility (EMC) of a technical system or just individual system components during the development and integration phase. In particular, all components and also the technical system (i.e. with all the components integrated therein) should preferably be checked in terms of measurement technology with regard to the EMC.

Such measurements can often only be carried out at a late stage of development.

Additionally or alternatively, EMC interference can also be calculated using numerical simulation. However, such simulations can only be carried out after the provision of

Information on, for example, built-in antenna systems, on-board networks (or generally electrical lines) and control units installed in the technical system can be carried out with a meaningful meaning. In addition, EMC risks are checked based on such information using so-called rules checkers, which can be computer-aided test protocols and / or test simulations.

The information required in each case or the real overall system that can be used for a measurement is generally only available after the concept development has been completed. Therefore, EMC problems (ie a lack of electromagnetic compatibility, for example an EMC below a required minimum limit and / or above a permissible risk factor) can only be determined in the series development phase. A first finding of the invention lies in the fact that EMC risks have often been underestimated in early concept phases, since, as described above, meaningful EMC checks are only possible in the series development phase. If problems are identified at this late stage of development, the necessary countermeasures can lead to undesirable additional costs and time delays.

It is therefore an object of the invention to improve the EMC determination of technical systems and, in particular, to enable them in an earlier development stage (for example, already within the first concept phases).

This object is achieved by a method and an arrangement according to the attached independent claims. Advantageous further developments are specified in the attached dependent claims. It goes without saying that the introductory explanations and features can also be provided or apply to the solution according to the invention, unless otherwise stated or evident.

The invention is generally directed to any technical systems which, for example, have at least one radio system, but more particularly to vehicles and in particular to motor vehicles (for example passenger cars).

A basic idea of the invention is that a possibility is provided for specifying an influencing variable that influences an EMC of a technical system and in particular a vehicle, and that the EMC of the technical system is determined based on this predefined influencing variable. It is also preferably provided that the predefined influencing variable is also varied, for example by using statistical and / or stochastic methods (for example a Monte Carlo simulation). This takes into account the fact that in the early stages of development it is not possible to precisely quantify all the sizes relevant for EMC, but within the scope of the rest

Development process still vary as expected. This provides an overview of which EMC and in particular which EMC variations or, in other words, the EMC bandwidth of the technical system is likely to be expected. In this way, scope for determining the predetermined influencing variable can also be estimated, for example depending on whether the determined EMC variations are critical

Areas or not. Further advantages of the solution according to the invention are first of all the possibility of saving costs and time during system development, since undesired EMC conditions can be recognized and corrected at an early stage.

The number of prototypes required can also be reduced during the development phase, since these have a higher probability of having the desired EMC properties from the outset using the solution according to the invention.

In addition, the solution according to the invention can be used to determine EMC with little

Spend time, especially when compared to detailed numerical simulations.

In general terms, the invention relates to a method and an arrangement for determining EMC and in particular for calculating an EMC risk factor, this in each case depending on at least one physical disturbance variable (corresponds to the above-mentioned influencing variable with potential influence on EMC) and preferably also on a stochastic one Analysis is done. This preferably takes place in a concept design phase of the system. By entering the relevant influencing factors for the corresponding concepts, such as the position of EMC-relevant components, routing of cables, cable lengths and properties of antenna structures, the

physical EMC disturbances and their probability of occurrence are calculated with a statistical expected value.

This method is preferably carried out in a computer-implemented manner and in particular by means of a software tool or a software application, by means of which a user can, for example, specify the relevant variables and / or obtain information about determined EMC properties. The invention also relates to an arrangement which can comprise or provide such a software tool or software application, in particular if the arrangement is or comprises a computer system on which the software tool or the

Software application is stored and / or executable.

In detail, the invention relates to a (preferably computer-based) method for determining the electromagnetic compatibility (EMC) of a technical system, with:

- (for example manual) specification (for example a value) of at least one influencing variable of the technical system (which can also be referred to as influencing parameters or parameters), the influencing variable having a potential influence on the EMC of the technical system; and - (preferably computer-based) determining an (ie at least one) EMC

Result quantity of the technical system based on a (or through a) variation (for example the predetermined value) of the influencing variable. The variation can e.g. within the framework of a stochastic and / or statistical calculation.

The EMC result variable determined based on the variation can also be referred to as a statistically and / or stochastically calculated EMC result variable. One advantage is that this enables a possible range of changes in the influencing variable within the others

Development phases can be taken into account or a general spectrum if an initial value of this influencing variable has not yet been adequately determined. Despite this uncertainty, statements about the EMC properties of the system can be made at early stages of development and the concept and / or further development can be adapted accordingly.

The EMC result variable can be an average value or an expected value of a plurality of EMC values (for example in the form of interference voltage values) determined, for example, for a specific frequency, the plurality of EMC values being obtained, for example, by varying the influencing variable can (for example, an EMC value for each variation step). The EMC result variable can also be a maximum value or minimum value of a corresponding plurality of EMC values. The EMC result variable can also be a (qualified) risk factor, which can be, for example, from a ratio of one of the above-mentioned example values to a predetermined, for example legal, guideline value (for example to a legally permitted maximum value).

It goes without saying that based on the variation of one influencing variable also several

Different EMC result variables of the type mentioned above can be determined.

In general, any values determined here can be displayed to a user, for example via a display device of the arrangement. This can be done graphically and / or using numerical values.

According to a further embodiment of the method and the arrangement, at least one further EMC result variable is additionally calculated based on (for example the value) the predetermined influencing variable, ie preferably without the influencing variable being varied. This can also be called an analytical calculation of the EMC result variable. The analytically and statistically / stochastically determined EMC result variables can be displayed to a user, in particular at the same time, in order to increase the meaningfulness of the results.

According to a preferred variant, the analytical calculation (and preferably also output) of the EMC result variable takes place in a step upstream of the statistical / stochastic calculation. Based on the analytically determined EMC result variables, a user can draw conclusions for the statistical / stochastic calculation (for example, identify a suitable range of variation of an influencing variable or select potentially relevant influencing variables for the statistical / stochastic calculation). The

Statistical / stochastic calculation could also be omitted, for example if the analytical results already show sufficient EMC compatibility, which is unlikely to be endangered even in the context of expected variations in the influencing variable.

According to the invention, a step-by-step procedure can be carried out, in which an analytical (preferably first) analytical and a statistical / stochastic determination of the EMC result variable takes place. Under statistical / stochastic is within this

Disclosure generally to understand a statistical and / or stochastic characteristic.

In a development of the method and the arrangement, the influencing variable is assigned to a specific system component and the method is used for at least one further influencing variable which is assigned to the same system component.

In particular, the EMC result size can be based on the variations of both

Influencing factors are determined.

The system component, which can generally also relate to a system property, can be, for example, one of the following: a line bundle, a control device, an antenna or antenna structure, a RED (radio equipment directive), a radio system

(Radio Equipment Directive), an EMVU (electromagnetic environmental compatibility) and an SAR (specific absorption rate). It can also be a system component composed of the above-mentioned examples (for example a control unit with a line bundle connected to it).

According to this variant, it can be taken into account, for example, that one

Line bundles not all potential influencing variables (or parameters) are known in advance, but several of them can be varied. This can be, for example, a damping factor, a position, a line length, a line spacing or act like that. These also represent general examples of influencing variables, regardless of the further training described here. Further examples of

Influencing variables (for example for an antenna structure) are an expected air impedance, a frequency band, an antenna factor or a position and in particular relative position (for example in the form of a distance specification, in particular to a measuring point or to another system component, which influence, for example, EMC properties can).

In general, all variable variables can be influencing variables in the sense of the present disclosure, which influence the EMC properties of the technical system and in particular at least one system component thereof. These are preferably variable quantities which can be varied in accordance with the procedure described here.

If two such influencing variables are varied for a system component, an EMC value can be determined for each variation step of both or just one influencing variable. If a plurality of variation steps are specified, what is within the scope of the present

General disclosure by (in particular purely arithmetical) making

Samples or iterations can take place, a mean value (and / or expected value), minimum value or maximum value from the total EMC values obtained, which has been explained above, can be selected as the EMC result variable.

According to a further variant, the variation takes place within a predefined one

Range of variation instead.

Alternatively or additionally, the variation can be carried out with a predetermined number of

Variation steps (or iterations or samples, for example by Monte Carlo

Simulation).

Furthermore, alternatively or additionally, the variation can take place in accordance with a predetermined distribution of the influencing variable values, in particular a statistical and / or stochastic distribution.

As described, according to a further development, values of the EMC result variable can be determined for a plurality of frequencies in a predetermined frequency range. According to a further aspect of the method and the arrangement, the influencing variable is assigned to at least one of the following system components or at least indirectly describes at least one of the following system components:

a line coupling within an electrical line bundle of the technical system;

- interference emission of a system component;

- a line fault within the technical system;

a transmission quality of a radio system of the technical system;

- An antenna structure built into the technical system;

- At least one frequency band from one installed in the technical system

Component;

- An electrical line laid in the technical system, in particular a

Routing of this;

- an EMVU (electromagnetic environmental compatibility) or, in other words,

Environmentally related EMVU magnetic fields, whereby base values for an exposure reference values can be used as well as an SAR (specific

Absorption rate).

As an alternative or in addition, the influencing variable can relate to or at least indirectly describe a route from a line installed in the technical system (for example signal and / or energy transmitted) and this route can be marked by a user in a computer system used to carry out the method. In particular, the route (or, in other words, route) can be entered via a preferably graphical user interface, for example by marking the route in a displayed vehicle outline or section. If a line is mentioned in the context of this disclosure, this can generally relate to an electrical line (for example a cable) and additionally or alternatively to a signal and / or energy-transmitting line.

The invention further relates to a (in particular computer-based) arrangement for determining the electromagnetic compatibility (EMC) of a technical system, with:

an input device by means of which a user can specify at least one influencing variable of the technical system, the influencing variable having a potential influence on the EMC of the technical system;

a calculation device which is set up to determine an EMC result variable of the technical system based on a variation of the influencing variable. The calculation device can be set up to determine the EMC result size by including a computer program product (for example a software program) (for example by storing it in a speech device of the calculation device), and can also be set up to execute this computer program product. As a result, a method can be carried out in accordance with any of the above and below aspects, and in particular the variation of the influencing variable can be carried out. More specifically, the computing device (or the arrangement in general) can be one

Computer program product include and the calculation device is set up by executing the computer program product to perform an opening-based method and in particular to determine the EMC result variable of the technical system based on a variation of the influencing variable

The arrangement can be implemented as a computer system or computer network and / or generally comprise at least one microprocessor. The input device can be used, for example, as a keyboard, mouse, touchscreen, microphone (for example for

Voice command inputs) or camera (for example for gesture inputs). The calculation device can comprise at least one microprocessor on which a software application or a software tool can be executed in accordance with any of the variants described herein.

The arrangement can comprise any further feature and any further development in order to provide all of the steps, effects and interactions described here. In particular, the arrangement can be set up to carry out a method according to any of the above and below variants. All of the explanations given here regarding identical process features also apply to the corresponding arrangement features.

The invention is explained below with reference to the attached schematic figures:

1 shows a flow diagram of a method according to an embodiment of the

Invention;

2 shows an example of an analytical calculation of an EMC compatibility, for example of a system component such as a control unit;

3 shows a further example of an analytical calculation of an EMC

Compatibility, for example of a system component consisting of a control unit with lines connected to it; FIG. 4 shows a further flow diagram that is specifically directed towards the measures for analytical and stochastic calculation of an EMC;

5 shows a computer-based graphical input option for input

Cable length;

6 shows the result of an analytical calculation as a curve of a determined frequency-dependent interference voltage (EMC result variable) over a predefined frequency spectrum;

FIG. 7 shows representations analogous to FIG. 6 but for a stochastic calculation;

and

Figure 8 shows a schematic representation of an arrangement according to the invention.

1 shows a flow diagram of a method according to an embodiment of the

Invention, which is carried out on an arrangement, not shown, according to the invention. The latter can generally be designed as a conventional PC (for example in the form of a smartphone, laptop, desktop PC or tablet). The following descriptions focus on the EMC determination for a vehicle development.

The method is carried out by means of a software tool (also simply called a tool) that is executed on the arrangement (for example by processing program instructions of the software tools on a microprocessor of the arrangement). The tool is started in a step S1. In a step S2, a predefined EMC module of the tool is selected. The EMC modules relate to various system components and / or system areas of a vehicle that the user can select in order to check their EMC in the concept phase.

Depending on the selected EMC module, the user will have different options in step S3

Influencing variables (parameters) are displayed, the values of which he can determine for a preferred (but not mandatory) first analytical calculation. An analytical calculation of an EMC influencing variable then takes place in step S4. Since the EMC in general

is frequency-dependent, this is preferably done for a plurality of frequency values within a predetermined frequency spectrum or range. In step S5, therefore

The determined EMC influencing variable is output via the frequency spectrum,

for example in the form of a graph. From this, the user can draw first conclusions as to whether the case examined by him is likely to be critical or non-critical with regard to the EMC and, based on this, make initial adjustments and / or adapt the subsequent stochastic calculation. As will be explained in more detail below, the stochastic calculation is carried out in step S6. If this does not lead to the desired results, one can be carried out in step S7

Adjustment and re-execution of this or all calculations take place.

The method can be ended in accordance with steps S8 (documentation, calculation report) and S9 (close tool).

FIG. 2 shows an example for the analytical calculation of the EMC of a vehicle control unit (relates to step S4 from FIG. 1). All of the formulas given in this disclosure are taken from the specialist literature, so that their variables also correspond to conventional definition or have conventional meaning. Nevertheless, the formulas are only examples and an EMC calculation could also be carried out based on other suitable forms.

The range of different EMC modules 102-106 according to step S2 from FIG. 1 is indicated in an area 10 of FIG. 2 (100: Tool start page, module 102:

Interference emission system, module 104: line-line, module 106: total SA (total interference emission)). In the case shown, the interference emission of a specific system or a system component is examined in the form of a control device which comprises an antenna.

Various common formulas are specified in the left-hand area (block 108) in order to determine generated electrical fields of the antenna (index ant), of the control device (index sg) and of the entire vehicle (index vehicle or vehicle). The variable d can be understood as a (relative) position variable. There is a frequency dependency for the antenna via the power variable P _T.

Further abbreviations and variables stand for or imply the following: d: distance between antenna and control unit; P _T : power variable as a function of the antenna and the frequency range (is summarized in a table); dsc / G _T = 1; E _SG : the user can specify any values for this purpose, E generally representing the electric field strength in the context of this disclosure; Zo = 120p; AF: antenna factor from table; V _interference : interference voltage.

Further input variables E of block 108 are also indicated, which can be the following: air resistance, position of the system, vehicle type, frequency band, “antenna radiated power” (radiated power of the antenna), antenna factor. The specified air resistance can also be referred to as air impedance and represented by the variable Z (or Zo) _. Possible in advance about the vehicle type Position margins are determined and / or data or variable values are read from stored tables. The input variable E can also include data “from component test / worst case TL”, which takes into account that data or values from component tests that have already taken place can be used or values according to a specified “worst case” (ie worst case scenario).

Analogously to FIG. 2, FIG. 3 shows formulas for an EMC calculation of a system from a control device with lines connected to it (both with only one (area 110) and with two lines, area 112). Cases of differential and common currents are considered, both of which can lead to the generation of an electric field. The variable R relates (as a relative position specification) to a distance, for example between a line and a measuring point or antenna pole.

The other specified variables stand for the following: f: frequency; K: correction factor (5 cm, -22db); I _com : common current; _f r: differential current; L: cable length; d: distance to ground. The current values can be derived from the worst case or entered manually. The two last listed variables L, d can also be entered manually.

The course of the analytical and stochastic calculation is explained in FIG. 4 (compare steps S4-S6 from FIG. 1), in each case for a plurality of frequency values from one

Frequency interval or frequency range are carried out. According to the analytical

Calculation (block 111), at least one influencing variable (parameter) is selected in accordance with block 113 and a variation range is defined for this (deviation between 1% and 30%). A distribution is then also specified which defines how the values of the influencing variable to be varied are distributed within the range of variation (marked as input I). For this purpose only, one can choose between a Gaussian distribution and a uniform distribution. A Gaussian distribution can be considered, for example, if it can be expected that the value of the influencing variable mainly fluctuates around an average value (for example, since a construction space is limited in such a way that a distance value cannot be varied significantly).

A uniform distribution can be considered, for example, if it can be expected that the value of the influencing variable will vary arbitrarily within the range of variation, for example because a distance value can be arbitrarily determined due to the lack of space constraints.

A Monte Carlo simulation is then carried out for the stochastic calculation as a preferred but not mandatory procedure (block 114). To do this, use a Random function and taking into account the specified distribution and the variation range, samples are taken mathematically, the number of iterations or the number of samples taken being selectable. Metaphorically speaking, this gives the information about which EMC properties are most likely to be expected, even if the influencing variable is still to be expected. As a result, a mean value, a deviation from the expected value or a risk factor can in particular be obtained in block 116 and then displayed (see also the following figures). This can be frequency-dependent, ie each of these values can be determined for a specific frequency value in a predetermined frequency range.

For the exemplary case of an influencing variable in the form of a position specification, the stochastic calculation using Monte Carlo simulation is explained again.

The following is entered or determined as preparation:

a deviation or tolerance to be taken into account (for example from 1% to 30%), the deviation corresponding to a difference from a maximum position minus a (current) position;

a maximum position (for example, as an absolute position plus a tolerance value); and

a minimum position (for example, as an absolute position minus a tolerance value);

The following is also specified for the simulation in order to select the samples:

the number of iterations (N); and

choosing the samples as normal distribution (i.e., Gaussian distribution) or equal distribution.

In the case of the normal distribution, the position is regarded as m (expected value) and a disturbance as a function of the expected value. The random function is defined as: sigm = (deviation * 35%) / 100

It is also specified that the iteration should be carried out as follows: 68% in

Range m +/- sigm; 28% in the range m +/- 2 * sigm; 4% in the range m +/- 3 * sigm. This procedure is particularly advantageous when, as is generally the case in concept phases, several influencing variables can still be subject to variations. As shown below, a corresponding range of variation and

preferably also a distribution can be determined. Using Monte Carlo simulations or sampling, EMC properties can then be determined under a simultaneous variation of all influencing factors, so to speak. As a result, the potential of the

Concept for compliance with a desired EMC can also be estimated in view of other possible changes during the development process.

In the following, a step-by-step procedure for carrying out the above-described method using the tool used is explained in more detail. The following steps relate to inputs or interactions by means of (or with) a graphical user interface and in particular by means of input areas of the tool, the interactions below using input fields, tabs, per

Mouse-clickable virtual input objects or the like can be enabled:

In the software tool, a tab "EMC topics" is selected, which can be used to select the individual areas, assemblies and / or modules that are to be examined with regard to their EMC. The following topics can be selected as examples: Coupling line / line; Leadership / Mass Concept Analysis; Fault emission through the position of the control unit; Fault transmission of an entire system; RED (radio equipment directive).

Below it is assumed that coupling is the topic

Line / line is selected.

- Then switch to a tab "Vehicle class" and from the

Choices selected a vehicle type for example from the following classes: Small; Compact; Midsize; Fullsize. At least for the last three classes, the option "Variant" can also be offered.

- Then switch to the "Antennas / Frequency" tab and a start and end frequency is defined via predefined input fields (by manually entering the corresponding values in MHz, for example 100 MHz to 500 MHz). Using a button, these values can be validated and a frequency interval (calculation interval) can be set (for example in kHz, for example 1100 kHz). After defining this interval, you can click on the "Apply frequency value" button and a number of measuring points (within the frequency interval) are determined and displayed (in this example, 363). An EMC influencing variable is then determined for each of these measuring points, and a plurality of EMC values are preferably determined by means of the stochastic calculation, on the basis of which a final EMC influencing variable (for example the expected EMC value for at least one measuring point in the frequency interval) can then be determined.

- Then you switch to a "Parameters" tab

Influencing factors for an initial analytical calculation that were not automatically determined by the selection of the vehicle class. This is the damping factor of the coupling (for example at

shielded cable), which can be entered as a corresponding numerical value in decibels.

It is also the route of laying the cables inside the vehicle. This can be entered directly as a numerical value (length of the interference line), for example in millimeters. Alternatively, as further shown in FIG. 5, it can be defined by a user marking the installation path in a vehicle representation (for example by selecting the corresponding grid or fields in the representation shown there). Influencing variables such as a cable length can then be determined automatically.

As can be seen from FIG. 5, a top view of the vehicle (or its floor plan) is shown, which is subdivided into a uniform square grid or grid. A side view is also shown. Furthermore, a so-called circuit diagram shows a right-hand matrix-shaped area with grids analogous to the vehicle views. An operator can specify in which areas a line runs by clicking on the individual grids (for example in the circuit diagram, which is then shown graphically in the vehicle views). The line length can then be estimated by evaluating or assembling the overall activated grid (see FIG. 5).

In detail, a field "Recalculate route" can be activated in an input mask and any starting point in the grid (or circuit diagram) be set. Starting from this starting point, possible path directions are displayed and the path finally selected can be confirmed, whereupon the line length can be determined and adopted automatically.

It is generally provided that several such circuit diagrams are also displayed, one for example for a floor area P and one for a (typically smaller) roof area D (see FIG. 5). Thus, an operator can determine line lengths for lines that run either in the floor area or in the roof area, and this can also be shown accordingly in the top view and side view of the vehicle.

Finally, the tool can be used to determine the following other influencing variables: coupling length between control line and sacrificial line, which is determined analogously to the line length, although only common sections with the interference line are of interest and can therefore be selected; a distance to GND (ground); a termination impedance (sacrificial line) and internal impedance related to the interference line; a relative permittivity and relative permeability (1 equals air).

Furthermore, an input voltage can be entered as a constant voltage or PWM signal, the latter allowing further settings (for example an amplitude, sampling time, entry time, duty cycle or basic frequency).

Based on this, an analytical calculation is then carried out, the results of which are shown in FIG. 6. Individuals are distributed over the frequency range under consideration

(Frequency-dependent) EMC values in the form of interference voltages in the unit dBmV, which in the context of this disclosure can apply to any EMC values (i.e. each EMC value can be determined frequency-dependently and / or in the named unit). The graphic representation is deposited by horizontally extending areas 120-122, with an uppermost narrow (120) a critical value range, the middle width (121) a neutral value range (ie neither clearly critical nor clearly uncritical) and the lower wide strip 122 marked an uncritical range of values.

The stochastic calculation for individual influencing variables (eg cable length, coupling length, distance to GND, radius of the cable, distance between cable and cable) can then be used to determine the variation ranges and distributions explained above. A maximum deviation of a previously determined value of the influencing variable represents the

Tolerance range or the range of variation for the calculation. Likewise, the distribution functions explained above (uniform distribution, normal distribution) can be selected, which indicate the probability of the occurrence of an influencing variable value in the tolerance or variation range per iteration. In addition, the desired number of iterations (i.e. samples) can be defined for each influencing variable, which for each measurement point (i.e. each

considered frequency value) are to be carried out within the considered frequency range.

The representation of the results of the calculation is then shown in FIG. This takes place again over the frequency range under consideration. FIG. 7 shows in area a) that each

considered frequency value in the frequency range due to the for example at least 100 and optionally also 1000 or more iterations there is a value distribution, so that a minimum value, a maximum value and an average value (black band) of this distribution can be determined for each frequency value under consideration. The axes and horizontally stored areas are defined analogously to FIG. 6. Compared to the purely analytical result from FIG. 6, the user thus receives more meaningful feedback about how likely it is that critical EMC areas will actually be reached.

The ultimately determined EMC result variable can preferably be the preferably frequency-dependent expected value (for example the expected EMC interference voltage per frequency) determined in the context of the stochastic consideration. This is entered in FIG. 7 in area b), namely as an essentially horizontal curve 140 with only a few swings. Also shown is a curve 142 provided with significantly larger deflections, which indicates an EMV result variable determined in an analog but analytical manner. Such a representation can also be used to assess the deviation of the analytically and stochastically determined EMC.

Additionally or alternatively, an EMC result variable can also be preferred

frequency-dependent risk factor can be defined, which indicates the ratio of the determined (frequency-dependent) mean to a legal limit.

FIG. 8 finally shows a schematic illustration of an arrangement 200 according to the invention. An input device 210 is shown as a conventional keyboard (alternative examples have been mentioned above) and the calculation device 220 as a conventional PC (alternative examples have been mentioned above). The calculation device 220 comprises a computer program product (ie a software tool) and is configured to execute a method according to any aspect described herein when executing this computer program product (for example by means of a microprocessor of the computing device 220).

Reference list

10 area

100 software tool

102 Interference emission system

104 line-line

106 total SA

108 block

E input variable

110-116 blocks

I input

P Floor area wiring diagram

D Circuit diagram roof area

120-122 area

140 frequency-dependent curve with stochastically determined expected values

142 frequency-dependent curve with analytically determined expected values

200 arrangement

210 input device

220 calculation device

Claims

1. Procedure for determining the electromagnetic compatibility (EMC) of a technical system, with:

- Specifying at least one influencing variable of the technical system, the influencing variable having a potential influence on the EMC of the technical system;

- Determine at least one EMC result variable of the technical system based on a variation of the influencing variable.

2. The method according to claim 1,

wherein at least one further EMC result variable is additionally calculated based on the predefined influencing variable.

3. The method according to claim 1 or 2,

wherein the influencing variable is assigned to a specific system component and the method is used for at least one further influencing variable that is assigned to the same system component.

4. The method according to claim 3,

whereby the EMC result variable is determined based on the variations of both influencing variables.

5. Method according to one of the preceding claims,

wherein the variation takes place within a predetermined variation range and / or with a predetermined number of variation steps and / or according to a predetermined distribution of the influencing variable values, in particular a statistical and / or stochastic distribution.

6. The method according to any one of the preceding claims,

wherein values of the EMC result variable are determined for a plurality of frequencies in a predetermined frequency range.

7. The method according to any one of the preceding claims,

the influencing variable being assigned to at least one of the following system components of the technical system or at least indirectly describing at least one of the following properties of the technical system: a line coupling within an electrical line bundle of the technical system;

- interference emission of a system component;

- a line fault within the technical system;

a transmission quality of a radio system of the technical system;

- An antenna structure built into the technical system;

- At least one frequency band from one installed in the technical system

Component;

- An electrical line laid in the technical system, in particular a

Routing of this;

- electromagnetic environmental compatibility.

8. The method according to any one of the preceding claims,

the influencing variable relates to or at least indirectly describes a route of installation from a line installed in the technical system, and this route of route is used by a user in one to carry out the method

Computer system is markable.

9. Arrangement (200) for determining the electromagnetic compatibility (EMC) of a technical system, with:

- an input device (220), by means of which a user can specify at least one influencing variable of the technical system, the influencing variable having a potential influence on the EMC of the technical system;

- A calculation device (210) which is set up to determine at least one EMC result variable of the technical system based on a variation of the

Determine influencing variable.