On-board energy system, vehicle therewith and method for constructing an on-board energy system

Abstract

The invention relates to an on-board power supply system (EnBN) of a vehicle (F), comprising at least one electronic fuse (e_Fuse), the current-time characteristic curve (K_eFuse, T_eFuse) of which is above a lower current-time characteristic curve I specified for the position (Pos) of this fuse (e_Fuse) in the on-board power supply system (EnBN). eFuse_low ), where the lower current-time characteristic (I eFuse_low ) between a continuous current value (I DC_eFuse_low ) and a peak current value (I Peak_eFuse_low ) at least partially a form according to I e F use _ low = k 4 τ 4 where “k4” is a constant of unit [A 4 ·s] and τ corresponds to a time period. The invention also relates to a corresponding vehicle (F). The invention further relates to a method for constructing an on-board energy system (EnBN) and to a computer program product comprising code which, when executed on a data processing device, carries out the method.

Description

[0001] The invention relates to an on-board power supply system of a vehicle having at least one electronic fuse. The invention also relates to a vehicle with such an on-board power supply system. The invention further relates to a method for constructing such an on-board power supply system, in which components and lines provided for the on-board power supply system, including at least one electronic fuse, are specified in a design phase, wherein at least one respective current-time characteristic curve is specified for at least one electronic fuse. The invention also relates to a computer program product comprising code which, when executed on a data processing device, carries out the method. The invention is particularly advantageously applicable to motor vehicles.

[0002] DE 10 2014 214 840 A1 discloses a device for monitoring a high-voltage electrical system of an electrically operable vehicle for the presence of an overload, wherein the high-voltage electrical system comprises as components one or more energy sources and / or one or more energy sinks, which are each connected via a conductor strand arrangement to a first supply potential line and to a second supply potential line.Each of the components is assigned a current sensor which is designed to detect a current flowing through the component in question and to transmit information representing the level of the current to an evaluation unit for evaluation, wherein the evaluation unit is designed to compare the current with a first current threshold and a second current threshold and to output a switch-off signal at least for the component assigned to the current sensor if, as a first criterion, the level of the current and the duration of the level of the current lie between the first and the second current threshold.

[0003] DE 10 2022 134 411 A1 relates to an on-board power supply system of a vehicle, comprising at least one interference source and at least one interference sink, wherein a respective current measuring device is provided which is configured to continuously measure values of a current output by the interference source, a respective voltage measuring device is provided which is configured to continuously measure values of a terminal voltage at the input of the respective interference sink, a multi-stage frequency filter with several selectively switchable filter stages, each with fixedly parameterized filter parameters, and a control device for switching the filter stages are integrated in a filter device, the control device is communicatively coupled to the at least one current measuring device and the at least one voltage measuring device for receiving the measured values, the control device is configured toto continuously calculate an associated transfer function from the temporal profiles of the measured values of respective pairs of current measuring device and voltage measuring device, and the control device is configured to switch the filter stages depending on the at least one calculated transfer function,

[0004] DE 10 2022 124 564 A1 discloses a method for determining filter parameters of a passive bandpass frequency filter to be installed in a vehicle's power system, in which a model of the power system with interference sources and interference sinks is set up, an access point of the bandpass frequency filter is determined in the model of the power system and then, starting with k = 1, (a) a k-th bandpass filter stage is added to the bandpass frequency filter by (i) specifying a filter stage frequency, then (ii) specifying a filter stage resistance, then (iii) specifying a filter stage capacitance and calculating a filter stage inductance from the filter stage frequency and the filter stage capacitance, and then (b) calculating based on the model,whether transfer impedances caused by the bandpass frequency filter between the interference sources and the interference sinks exceed a predetermined maximum deviation from associated reference transfer impedances, and (c) if the maximum deviation is not exceeded, the design of the bandpass frequency filter is completed, (d) while if the maximum deviation is exceeded, k is incremented and subsequently (e) steps (a) to (d) are repeated, wherein in step (a) (iii) the filter stage capacity is determined according to whether a stability boundary condition with a maximum filter stage capacity, an equilibrium boundary condition with a minimum filter stage capacity, or a loss boundary condition with a target filter stage capacity is selected.

[0005] It is the object of the present invention to at least partially overcome the disadvantages of the prior art and in particular to provide a more robust possibility.

[0006] This object is achieved according to the features of the independent claims. Preferred embodiments can be found in particular in the dependent claims.

[0007] The object is achieved by an on-board power supply system of a vehicle, comprising at least one electronic fuse, the current-time characteristic curve of which is above a first (“lower”) current-time characteristic curve I specified for the position of this fuse in the on-board power supply system. eFuse_low , with the lower current-time characteristic curve being between a first current value (“continuous current value”) I DC_eFuse_low and a second current value (“peak current value”) I Peak_eFuse_low > I DC_eFuse_low at least partially a form according to IeFuse_low=k4τ4 where “k4” is a constant of unit [A 4 ·s] and τ corresponds to a time period. The value of the constant k4 can vary, for example, depending on the current class of the electronic fuse or the eFuse class. For the time period τ, the following applies: in all use cases / operating points of a component "x" for which fuse tripping should not be permitted, the current demand averaged quadratically over each time period τ = [1 µs ... 600 s] Ix,RMS(τ)=max(1τ∫tt+τIx(t)2 dt) <IeFuse_low(τ) must be smaller than the corresponding current value of the lower current-time characteristic of the electronic fuse. The time period τ can also be referred to as a "modified" tripping time, which corresponds to a tripping time t for a constant current, but is based on its effective value for a variable current.

[0008] This form of the lower current-time characteristic curve causes a steeper gradient in the “pulse range” between the continuous current value I DC_eFuse_lowand peak current value I Peak_eFuse_low , which advantageously describes the usually actually existing form of the current-time characteristic of an electronic fuse considerably better than the relationship assumed analogously to fuses IFuse=k2τ2 with “k2” a “fuse constant” of unit [A 2 ·s]. Such fuse constants k2 can be found in fuse data sheets.

[0009] It is taken into account that electronic fuses show a noticeably different thermal behavior compared to conventional fuses: for example, they can conduct a higher current in the pulse range following I DC_efuse_low However, due to their thermal connection to a circuit board and its heating, they have a lower current carrying capacity in the pulse range in the direction of I peak_efuse_lowBy taking the different behaviors into account, it can be advantageously achieved that electronic fuses for reliably preventing thermal overload can be selected particularly easily during the design phase of the on-board power system and then used in the on-board power system. Furthermore, the electronic fuses can be dimensioned particularly small right from the design phase. This in turn advantageously saves costs and installation space for the electronic fuses as well as for design adjustments with little effort. In particular, the lower characteristic curve can be used to ensure that the electronic fuse never trips at the considered position in fault-free operation in all use cases / operating points of the component. The reason for the tripping of the electronic fuse / eFuse can, for example, be a fault on the electronic fuse - e.g.This could be implemented line protection (in the form of a programmed algorithm) or thermal heating of the eFuse. In a further development, the electronic fuse need not only trigger in the event of thermal heating, but can also trigger programmatically.

[0010] The current-time characteristic of a specific electronic fuse considered for installation at the position or actually installed corresponds in particular to a respective minimum of a combination of a programmed switch-off characteristic and an isothermal switch-off characteristic of the electronic fuse.

[0011] The on-board energy system is, in particular, the on-board energy system of a vehicle. The vehicle can be a vehicle with only an internal combustion engine as the drive unit, a vehicle partially powered by an internal combustion engine and at least one electric motor (e.g., a hybrid vehicle), or a fully electrically powered vehicle (e.g., a battery-powered vehicle, BEV, or a fuel cell-powered vehicle, FCEV). The vehicle can be a motor vehicle (e.g., a motor vehicle such as a passenger car, truck, bus, etc., or a motorcycle), a railway, a watercraft (e.g., a boat or ship), or an aircraft (e.g., an airplane or a helicopter).

[0012] An electronic fuse can also be referred to as an "eFuse" (after the English term "electronic fuse"). Electronic fuses are generally well known and comprise one or more semiconductor switches. Electronic fuses can be constructed using several discrete components or as a single integrated component. The on-board power supply system can comprise one or more electronic fuses. The electronic fuse can be used in particular to prevent thermal damage caused by electrical current flow, particularly to electrical cables and / or components located downstream of or behind the electronic fuse, and is functionally similar to a conventional fuse. The electronic fuse can also be used to protect contact systems.

[0013] Electronic fuses have so far been characterized, analogously to melting fuses, by their current-time characteristic, which is typically plotted in a double-logarithmic (I; τ) diagram and indicates the time period τ for a specific tripping current I. The current-time characteristic usually has a lower, known as the continuous current value I DC which is dimensioned so that the fuse at constant current I ≤ I DC does not trip. The current-time characteristic usually has an upper value, known as the peak current I Peak which is dimensioned so that the fuse is tripped at current I ≥ I Peak On the current axis between the continuous current value I DC and the peak current value I Peaklies the area or section, also known as the “pulse range”, in which the current-time characteristic is usually described as decreasing linearly with the tripping current I (apparently due to the double-logarithmic scaling).

[0014] The current-time characteristic curve corresponds to a special representation of the limiting load or melting integral. The current-time characteristic curve of a specific electronic fuse is often specified by the fuse manufacturer, e.g., in a data sheet.

[0015] The fact that the current-time characteristic of the electronic fuse actually installed or intended for installation lies “above” a lower current-time characteristic specified for the position of this fuse in the on-board power supply system means, in particular, that the lower current-time characteristic is specified at the position intended for an electronic fuse in the layout or design or assignment plan of the on-board power supply system and that the current-time characteristic of an electronic fuse actually to be installed or intended at this position should be above this lower current-time characteristic. “Above” is understood to mean that for a specific tripping current I, the time duration τ of the electronic fuse is greater than or equal to the break time t at the intended position and / or for a specific time duration τ, the tripping current I of the electronic fuse is greater than or equal to the tripping current I at the intended position.This ensures that the electronic fuse does not trip before the lower current-time characteristic curve.

[0016] It is a further development that the lower current-time characteristic I eFuse_low the above equation (1) in the entire pulse range between the lower continuous current value I DC_eFuse_low and the upper peak current value I Peak_eFuse_low fulfilled.

[0017] It is a further development that the lower current-time characteristic I eFuse_low the above equation (1) is only fulfilled in at least one section of the pulse range. In at least one remaining section of the pulse range, the lower current-time characteristic curve I eFuse_low then take on a different form, e.g., according to the known equation (2). It is a further development that the lower current-time characteristic I eFuse_low Equation (1) at least starting from the upper peak current value I Peak_eFuse_low towards smaller tripping currents I.

[0018] It is an embodiment that the lower current-time characteristic curve assigned to the position takes on a form in which, with respect to a current-time characteristic curve modeled on a conventional fuse or at the same position in the on-board power system, its continuous current value I DC This advantageously simplifies the design of the lower current-time characteristic. This can be implemented in such a way that in a design phase the continuous current value I DC_eFuse_low the lower current-time characteristic curve to the continuous current value I DC the conventional fuse, additionally a peak current value I Peak_eFuse_low with I Peak_eFuse_low > I DC_eFuse_low and the lower current-time characteristic curve is then in the pulse range on the I-axis between I Peak_eFuse_low and I DC_eFuse_low according to Equation (1). The peak current value I Peak_eFuse_lowresults from assumptions, e.g. regarding the maximum current carrying capacity of the electronic fuse and the cables, contacts, etc. connected to it at its position. If a peak current value I Peak_eFuse_low known, e.g. due to the previous use of a characteristic curve of an electronic fuse, which is based on a conventional fuse, this peak current value can be defined as I Peak_eFuse_low be taken over.

[0019] One embodiment is that the section of the lower current-time characteristic curve in the pulse range, formed according to Equation (1), intersects a section of the current-time characteristic curve formed according to Equation (2) corresponding to a conventional fuse at a predetermined intersection point. This provides the advantage that the height position of the lower current-time characteristic curve in the pulse range associated with the position can be determined in a simple and practically sensible manner.

[0020] It is a design that the lower current-time characteristic and the current-time characteristic I corresponding to the fuse Fuse_low at 25% on the section of the (particularly the same) continuous current value I DC_eFuse_low to the (especially the same) peak current value I Peak_eFuse_low intersect, i.e., 25% of the way along the I-axis of the current-time diagram from the continuous current value to the peak current value. The intersection point is therefore closer to the continuous current value than to the peak current value.

[0021] It is a design that the continuous current value I DC_eFuse_low in a range [0.7, ..., 0.8] of the fuse rating I N This is advantageously particularly easy to implement. The fuse rating can also be referred to as the rated current.

[0022] However, it is also possible to set the continuous current value I DC_eFuse_low be designed in stages with respect to the tripping current I, e.g. so that the continuous current value IDC_eFuse_low for I < 100 A a value between 70% and 80% of the fuse rating I N , for I between 100 A and 200 A, it is set to a value between 60% and 70% of the fuse rating and for I > 200 A, it is set to a value between 55% and 60% of the fuse rating.

[0023] It is a design that the peak current value I Peak_eFuse_low the lower current-time characteristic to a value in the range [4, ..., 5] of the fuse rating I N is set.

[0024] It is a further development that the peak current value I Peak_eFuse_low has a limitation to I = 200 A for fuse ratings up to 200 A and to I = 250 A for fuse ratings above 200 A.

[0025] It is an embodiment that an upper current-time characteristic curve l is assigned to a designated position of an electronic fuse in the on-board power supply system. eFuse_high which is above the lower current-time characteristic IeFuse_low at this position. The upper current-time characteristic advantageously facilitates the specification of the guaranteed tripping of the electronic fuse (maximum current) to ensure line protection, as well as a robust selectivity design. In particular, deviations from the (nominal) current-time characteristic specified by a manufacturer of the specific electronic fuse used, e.g. due to manufacturing tolerances and / or varying ambient conditions, can be reliably and easily taken into account. This design takes into account that conventional fuses only have one tripping characteristic ("fuse characteristic"), which is specified in the IEC. Fuse characteristics exhibit a scatter depending on many factors, which, however, is not explicitly specified. The additional definition of the upper current-time characteristic l eFuse_highThis dispersion / variation is now covered for electronic fuses, whereby, for example, the line protection algorithm of the electronic fuses, the thermal shutdown behavior of the electronic fuses and their printed circuit boards / PCB connection, line and contact system protection, etc. can be taken into account.

[0026] It is a further development that the position of the electronic fuse both the lower current-time characteristic I eFuse_low as well as above and at a distance from it the upper current-time characteristic l eFuse_highare assigned. This has the advantage that the position of the electronic fuse in the on-board power system is assigned a characteristic band or "corridor" in the current-time diagram, within which the current-time characteristic of the specifically used electronic fuse should lie. This corridor advantageously facilitates the selection of small-sized and thus cost-optimized electronic fuses, which at the same time reliably enable shutdown at a maximum current, and thus a particularly robust selectivity design. The fact that the upper current-time characteristic l eFuse_high above and spaced from the lower current-time characteristic curve I eFuse_low includes in particular that I DC_eFuse_high > I DC_eFuse_low and I Peak_eFuse_high > I DC_eFuse_low as well as in the pulse range in between for each I l eFuse_high > I eFuse_low This further development therefore includes the fact that the lower current-time characteristic curve I eFuse_lowand the upper current-time characteristic l eFuse_high neither touch nor cut. The assignment of an upper current-time characteristic curve and a lower current-time characteristic curve to a position of an electronic fuse in the on-board power system can be considered an independent invention - regardless of their shape. It therefore applies to both pulse ranges of the lower current-time characteristic curve according to Equation (1) and / or Equation (2).

[0027] In general, the upper current-time characteristic curve needs l eFuse_high but at least only within the pulse range above the lower current-time characteristic curve I eFuse_low to lie, ie that for a certain tripping current I the time period τ satisfies the inequality t [I eFuse_high ] > t [I eFuse_low ] is satisfied. Conversely, for a certain time period τ, the inequality I [I eFuse_high ] > I [I eFuse_low ]. In general, I DC_eFuse_high ≥ I DC_eFuse_low and I Peak_eFuse_high ≥ I Peak_eFuse_low apply.

[0028] It is a design that the upper current-time characteristic l eFuse_high between a corresponding lower continuous current value I DC_eFuse_high and a corresponding upper peak current value I Peak_eFuse_high takes a form according to Eq. (2), where l eFuse_high a value of the upper current-time characteristic, I a tripping current and t a break time. The pulse range is therefore described using the I 2 t-behavior, which is described by k2 or by Equation (2). This allows the upper characteristic curve to fulfill its function of thermal line protection particularly reliably in the event of a fault, since the isotherm of a line follows a k2 value. By selecting Equation (2) in the pulse range, the upper current-time characteristic curve can be closely aligned with the isotherm of a line, which allows for a particularly wide corridor. The I 4 t-behavior of the lower current-time characteristic curve I eFuse_low, which is described by k4 or by Eq. (1), was chosen in order to be able to better utilize the current carrying capacity of the electronic fuse by taking into account the thermal tripping behavior of the electronic fuse.

[0029] However, the upper current-time characteristic curve in the pulse range can generally also take a different form, e.g. according to Eq. (1) or alternately in sections according to Eq. (1) and Eq. (2).

[0030] It is a design that the continuous current value I DC_eFuse_highThe upper current-time characteristic curve is set at 115% to 120% of the fuse's nominal value or rated current. This is more advantageous than conventional fuses, which allow up to 135%. This takes advantage of the fact that electronic fuses have significantly lower tolerances than conventional fuses. The upper current-time characteristic curve allows the advantages of semiconductors to be utilized and tolerances to be specifically reduced or eliminated from the system.

[0031] It is a design that the peak current value I Peak_eFuse_highThe upper current-time characteristic is set at 10 times the fuse rating. This is particularly advantageous for cascading multiple electronic fuses. If a much larger factor (e.g., 15) were selected, the tripping currents would overlap very quickly, triggering multiple electronic fuses in the cascade (instead of just the lowest one). The maximum tripping current is also limited when using Li-ion batteries.

[0032] It is a further development that the peak current value I Peak_eFuse_highThe upper current-time characteristic curve is limited to 450 A. This is particularly advantageous when using Li-ion batteries to limit the maximum current and avoid damage to such batteries (self-protection). This value is particularly useful for 12 V batteries and may be different for other types of batteries and / or battery voltages, especially low-voltage batteries.

[0033] It is an embodiment that the positions of several electronic fuses in the on-board power supply system are arranged in series or in a cascade manner.

[0034] In one embodiment, non-overlapping current-time characteristic curve bands are assigned to the positions of at least two electronic fuses arranged in cascade, in particular such that a lower current-time characteristic curve of a position arranged above or upstream in the on-board power supply system lies above and spaced from a lower current-time characteristic curve of a position arranged below or downstream in the on-board power supply system. This applies in particular to the case of two electronic fuses arranged directly one behind the other in the current direction, i.e., without another electronic fuse being interposed between these electronic fuses. This scheme can be extended to more than two electronic fuses.

[0035] The object is also achieved by a vehicle, wherein the vehicle has an on-board power supply system as described above. The vehicle can be designed analogously to the on-board power supply system, and vice versa, and has the same advantages. In particular, the on-board power supply system can have at least one specifically installed electronic fuse, which has been selected according to the current-time characteristic curve(s) specified for its position in the design or circuit diagram.

[0036] The object is also achieved by a method for constructing an on-board energy network, in particular as described above, in which - components and cables intended for the on-board power system, including at least one electronic fuse, are specified in a design phase, - wherein at least one respective lower current-time characteristic curve is specified or predetermined for at least one position intended for an electronic fuse, - a specific electronic fuse is selected for this position, the current-time characteristic of which meets the specifications for the position for the electronic fuse and - the on-board power supply system is equipped with the selected electronic fuse.

[0037] The method can be designed analogously to the on-board power system and / or to the vehicle, and vice versa, and has the same advantages.

[0038] The fact that a specific electronic fuse is selected whose current-time characteristic meets the specifications of the intended electronic fuse can, for example, include the current-time characteristic of the specific electronic fuse being above the lower current-time characteristic of the associated position and possibly also being below the upper current-time characteristic of the position, if specified or predetermined.

[0039] It is therefore a design that - a respective upper current-time characteristic curve is specified for at least one position in the on-board power system intended for an electronic fuse, - a specific electronic fuse is selected for this position, the current-time characteristic of which meets the specifications of both the lower current-time characteristic and the upper current-time characteristic (i.e. lies within the specified characteristic range) and - the on-board power supply system is equipped with the electronic fuse selected at least partly on this basis.

[0040] It is an embodiment that positions for at least two electronic fuses arranged in cascade with one another are provided in the on-board power supply system, which fuses have non-overlapping current-time characteristic curve bands.

[0041] The object is further achieved by a computer program product comprising code that, when executed on a data processing device, implements the method described above, or at least its design phase. The computer program product can be designed analogously to the method, to the on-board power system and / or to the vehicle, and vice versa, and has the same advantages.

[0042] The above-described properties, features and advantages of this invention, as well as the manner in which they are achieved, will become clearer and more clearly understood in connection with the following schematic description of an embodiment, which is explained in more detail in connection with the drawings. Fig. Figure 1 shows a current-time diagram with the characteristics of a conventional fuse and an electronic fuse; Fig. 2 shows another current-time diagram; and Fig. Figure 3 shows a lower current-time characteristic curve and an upper current-time characteristic curve of an electronic fuse.

[0043] Fig. Figure 1 shows a current-time diagram as a double-logarithmic plot of a time period τ in s against a tripping current I in A. It shows the fuse characteristic K_Fuse of a conventional fuse, a programmed tripping characteristic K_eFuse of an electronic fuse, and an isothermal tripping characteristic T_eFuse of the electronic fuse. The associated fuses correspond to a current class of 10 A, selected here as an example. The fuse characteristic K_fuse has a continuous current value I DC_Fuse followed by a section formed according to Equation (2) that decreases towards higher tripping currents I. An upper value I Peak_Fusedoes not exist for fuses. K_eFuse and T_eFuse indicate the two tripping mechanisms of the electronic fuse, namely K_eFuse the programmed algorithm for protecting the line and T_eFuse the thermal self-protection of the electronic fuse. K_eFuse therefore corresponds to a mathematical / algorithmic description of the tripping characteristic of an electronic fuse without taking into account the isothermal tripping as internal self-protection of the semiconductor(s). T_eFuse, on the other hand, describes an isothermal tripping characteristic of an electronic fuse independent of the mathematical description of the characteristic curve K_eFuse. K_fuse has a smaller continuous current value I DC_eFuse and a larger peak current I Peak_eFuse on.

[0044] When selecting an electronic fuse as a replacement or instead of a conventional fuse, it should be avoided that the electronic fuse trips before the fuse. This is the case here due to the position of the isothermal tripping characteristic curve T_eFuse in a "critical" area B_krit of the pulse range. B_krit shows that a description of the pulse range for electronic fuses using Eq. (2), adopted from conventional fuses, is not very suitable. In order to better handle the thermal tripping of the electronic fuses (self-protection), the gradient k2 is increased in magnitude by replacing it with k4. This can prevent the use of an oversized electronic fuse, which is described by k2.

[0045] In order to avoid B_krit, an electronic fuse is used instead of the fuse during the design or design phase of an on-board power system, the respective minimum of K_eFuse and T_eFuse of which lies above the fuse characteristic K_Fuse of the fuse, as for which the relationship min (K_eFuse; T_eFuse) > K_Fuse applies for each relevant I.

[0046] Since so far the I 2 t-behavior in the pulse range of the fuse is also used to shape the pulse range of the characteristic curve K_eFuse of the electronic fuse, this results in the disadvantage that larger-than-necessary electronic fuses are used. A characteristic curve K_eFuse of the electronic fuse modeled in this way on a conventional fuse has a continuous current value I DC_eFuse_low and additionally a peak current value I Peak_eFuse_low between which the characteristic curve K_eFuse runs according to Eq. (2).

[0047] Fig. Figure 2 shows another current-time diagram with the fuse characteristic K_Fuse and the isothermal cut-off characteristic T_eFuse. The fuses belong to a current class of 15 A, but behave qualitatively analogously to Fig. 1.

[0048] In the current-time diagram there is also a “lower” current-time characteristic I eFuse_low which corresponds to a lower limit for the characteristic curves min (K_eFuse; T_eFuse) of electronic fuses that can be installed at a corresponding position in the on-board power system. The lower current-time characteristic curve I eFuse_low has the same continuous current value I DC_eFuse_low as the lower fuse characteristic K_Fuse and the same peak current value I Peak_eFuse_low like an electronic fuse of the same design, modeled after a conventional fuse. In the intermediate pulse range, the lower current-time characteristic curve IeFuse_low a shape according to Eq. (1). Consequently, it has a steeper (negative) slope than the fuse characteristic curve K_Fuse. This steeper slope in the pulse range maps the tripping curve T_eFuse of the electronic fuse there better than Eq. (2). This allows the characteristic curve min (K_eFuse; T_eFuse) to be advantageously aligned more closely to the lower current-time characteristic curve I eFuse_low than to the fuse characteristic curve K_Fuse, which allows the use of smaller dimensioned and therefore cheaper electronic fuses.

[0049] The height of the pulse range of the lower current-time characteristic curve I eFuse_low is advantageously set so that it intersects the pulse range of the fuse characteristic curve K_Fuse at 25% in the direction of higher I values.

[0050] Fig. 3 shows a lower current-time characteristic curve I eFuse_low and an upper current-time characteristic I eFuse_highwhich serve as “boundary lines” or limits at a specific position Pos for an electronic fuse e_Fuse of an on-board energy system EnBN of a vehicle F, within which or within a characteristic curve band or corridor Korr limited by them the characteristic curve min (K_eFuse; T_eFuse) of an electrical fuse then actually used should lie.

[0051] The lower current-time characteristic curve I eFuse_low has a Fig. 2 with a pulse range of the 4th order according to Equation (1). The upper current-time characteristic l eFuse_high In its general form, it corresponds to a fuse characteristic curve with equation (2) in the pulse range.

[0052] Advantageously, the following values apply: I DC_eFuse_low ≥[0.7, ..., 0.8] · I N ; I Peak_eFuse_low ═ [4, ..., 5] · I N ; I DC_eFuse_high ≥[1,15, ..., 1,20] · I N ; I Peak_eFuse_high ≥10 · I N with I N the fuse rating.

[0053] Of course, the present invention is not limited to the embodiment shown.

[0054] In general, “a”, “an”, etc. can be understood as a singular or a plural, in particular in the sense of “at least one” or “one or more”, etc., as long as this is not explicitly excluded, e.g. by the expression “exactly one”, etc.

[0055] A numerical value may also include the exact number stated as well as a usual tolerance range, as long as this is not explicitly excluded. List of reference symbols B_crit Critical area EnBN on-board energy network F vehicle e_Fuse electronic fuse I tripping current I DC_eFuse Continuous current value of the programmed shutdown characteristic I DC_eFuse_high Continuous current value of the upper current-time characteristic curve I DC_eFuse_low Continuous current value of the lower current-time characteristic curve I DC_Fuse Continuous current value of the fuse characteristic curve l eFuse_high Upper current-time characteristic curve I eFuse_low Lower current-time characteristic curve I Peak_eFuse Peak current value of the programmed shutdown characteristic I Peak_eFuse_high Peak current value of the upper current-time characteristic curve I Peak_eFuse_low Peak current value of the lower current-time characteristic curve Corridor K_eFuse Programmed tripping characteristic of an electronic fuse K_Fuse fuse characteristic curve Pos Position T_eFuse Isothermal tripping characteristic of an electronic fuse τ duration QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2014 214 840 A1

[0002] DE 10 2022 134 411 A1

[0003] DE 10 2022 124 564 A1

[0004]

Claims

[1] On-board power supply system (EnBN) of a vehicle (F), comprising at least one electronic fuse (e_Fuse), the current-time characteristic curve (K_eFuse, T_eFuse) of which is above a lower current-time characteristic curve I specified for the position (Pos) of this fuse (e_Fuse) in the on-board power supply system (EnBN) eFuse_low ), where the lower current-time characteristic curve I eFuse_low ) between a continuous current value (I DC_eFuse_low ) and a peak current value (I Peak_eFuse_low ) at least partially a form according to IeFuse_low=k4τ4 where “k4” is a constant of unit [A 4 s] and τ corresponds to a time period. [2] On-board energy network (EnBN) according to claim 1, wherein - the lower current-time characteristic I eFuse_low ) takes a form in which, with reference to a current-time characteristic curve modelled on a conventional fuse, a continuous current value (I DC_eFuse_low) is used, which corresponds to a continuous current value (I DC_Fuse ) corresponds to the fuse, - for the lower current-time characteristic I eFuse_low ) a peak current value I Peak_eFuse_low which is greater than its continuous current value (I DC_eFuse_low ), and - the section of the lower current-time characteristic curve I eFuse_low ) of the electronic fuse between the continuous current value (I DC_eFuse_low ) and the peak current value (I Peak_eFuse_low ) one according to IFuse_low=k2τ2 shaped section of the current-time characteristic (K_Fuse) of the fuse with “k2” a fuse constant of unit [A 2 s] at a given intersection point. [3] On-board energy system (EnBN) according to one of the preceding claims, wherein the lower current-time characteristic curve (I eFuse_low ) and the current-time characteristic curve corresponding to the fuse (K_Fuse) at 25% on the section from the continuous current value (I DC_eFuse_low) to the peak current value (I Peak_eFuse_low ) cut. [4] On-board energy system (EnBN) according to one of the preceding claims, wherein the continuous current value (I DC_eFuse_low ) of the lower current-time characteristic curve I eFuse_low ) is set to a value in the range between 70% and 80% of the fuse rating. [5] On-board energy system (EnBN) according to one of the preceding claims, wherein the peak current value (I Peak_eFuse_low ) of the lower current-time characteristic curve I eFuse_low ) is set to a value in the range of 4 to 5 times the fuse rating, in particular with a limitation to I = 200 A for fuse ratings up to 200 A and to I = 250 A for fuse ratings above 200 A. [6] On-board power supply system (EnBN) according to one of the preceding claims, wherein an upper current-time characteristic curve (I eFuse_high) which is above the lower current-time characteristic I eFuse_low ) is at this position (Pos). [7] On-board energy system (EnBN) according to claim 6, wherein the upper current-time characteristic curve (I eFuse_high ) between a corresponding lower continuous current value (I DC_eFuse_high ) and a corresponding upper peak current value (I Peak_eFuse_high ) a form according to IeFuse_high=k2τ2 where l eFuse_high a value of the upper current-time characteristic (I eFuse_high ) corresponds. [8] On-board energy system (EnBN) according to one of the preceding claims, wherein the continuous current value (I DC_eFuse_high ) of the upper current-time characteristic curve (I eFuse_high ) is set to a value in the range between 115% and 120% of the fuse rating. [9] On-board energy system (EnBN) according to one of the preceding claims, wherein the peak current value (I peak_eFuse_high ) of the upper current-time characteristic curve (I eFuse_high) is set at 10 times the fuse rating, in particular with a limitation of 450 A. [10] On-board power supply system (EnBN) according to one of the preceding claims, wherein the positions (Pos) of a plurality of electronic fuses (e_Fuse) in the on-board power supply system (EnBN) are arranged in a cascade-like manner with respect to one another and non-overlapping current-time characteristic curve bands (Korr) are assigned to the positions (Pos) of at least two electronic fuses (e_Fuse) arranged in a cascade-like manner with respect to one another. [11] Vehicle (F), wherein the vehicle (F) has an on-board energy system (EnBN) according to one of the preceding claims. [12] Method for constructing an on-board energy network (EnBN) according to one of claims 1 to 10, in which - components and lines intended for the on-board energy network (EnBN), including at least one electronic fuse (e_Fuse), are determined in a design phase, - wherein for at least one position (Pos) provided for an electronic fuse (e_Fuse) at least one respective lower current-time characteristic curve I eFuse_low ) is specified, - a specific electronic fuse (e_Fuse) is selected for this position, the current-time characteristic (K_eFuse, T_eFuse) of which meets the specifications of the position (Pos) for the electronic fuses (E_Fuse) and - the on-board energy system (EnBN) is equipped with the selected electronic fuse (e_Fuse). [13] Method according to claim 12, in which - for at least one position (Pos) provided for an electronic fuse (e_Fuse), a respective upper current-time characteristic (I eFuse_high ) is specified, - for this position (Pos) a specific electronic fuse (e_Fuse) is selected, whose current-time characteristic (K_eFuse, T_eFuse) meets the specifications of both the lower current-time characteristic I eFuse_low) and the upper current-time characteristic (I eFuse_high ) and - the on-board energy system (EnBN) is equipped with the selected electronic fuse (e_Fuse). [14] Method according to claim 13, wherein positions (Pos) for at least two electronic fuses (e_Fuse) arranged in cascade with respect to one another are provided in the on-board power supply system (EnBN), which have non-overlapping current-time characteristic curve bands (Korr). [15] A computer program product comprising code which, when executed on a data processing device, performs the method according to any one of claims 12 to 14.

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