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The high-frequency switching of power transistors in electronic systems can be a significant source of electromagnetic emissions (EMI). Simple measures like reducing the high-frequency disturbances by introducing an additional gate resistor lead to an increase of the switching losses. This creates a conflict of interests between the reduction of disturbances and high system efficiency. More complex active gate drivers offers improved compromises between EMI and efficiency. Avoiding steep switching slopes, overshoots or sharp edges are typical measures. The whole spectrum is modified this way and efficiency is still affected. In many cases, only a narrow banded modification of the spectrum might be needed to avoid the excitation of critical system resonances. This can be reached by a target signal-oriented control of the gate of the transistors. In the target signal the critical RF components should be reduced. Maximum control of the target signal is possible with fully synthesized gate signals. The reduction of some harmonics in the switching spectrum may lead to overshoots in time domain due to the Gibbs phenomenon. These overshoots may violate the physical limits of a transistor and cannot be realized. In this work, a method is presented to determine the target signal considering all physical limits. The found approach is applied in simulation to the signal of the drain-source voltage of a boost converter to reduce the harmonics in the FM broadcasting range. The gate control signal is determined for this application.

Communication systems with high data rates like CAN FD and Automotive Ethernet are increasingly used in automobiles. New safety-critical driving assistance functions can be realized with the help of these bus systems, but data transmission has to be very reliable. Road vehicles are a challenging electromagnetic environment because of the high density of electric and electronic devices. Power electronic systems can be very close to communication systems. The typical cable type for automotive communication systems is the unshielded twisted wire pair. Common mode disturbances cannot be reduced by this cable type. Due to unavoidable asymmetry in the communication system electromagnetic coupling can also induce critical differential mode voltages. For this reason, the immunity of communication systems to electromagnetic interferences has to be investigated in detail. In this paper, simulation models are presented and validated by measurements to quantify cable coupling to CAN FD and 100BASE-T1 Automotive Ethernet. Both, common and differential mode voltages caused by cable coupling are investigated. Based on measurements and simulations critical influencing parameters on mode conversion are discussed.

In many modern power electronic systems, fast-switching semiconductor devices are used to reduce switching losses. Due to steep switching waveforms and high switching frequencies, significant electromagnetic disturbances can be emitted. In contrast to conventional passive filter components, active cancellation methods are based on the controlled destructive interference between a noise signal and a corresponding anti-noise signal. Adaptive notch filters revealed themselves as a promising active EMI cancellation concept for periodic noise signals. In this work, adaptive notch filters are regarded in context of slowly time-varying periodic noise signals, e.g. pulse-width modulated signals as common in inverters. The corresponding noise signals consist of switching harmonics and adjacent sideband harmonics. Therefore, the notch filter’s bandwidth comes into focus and an analytical approximation for the ideal adaptive notch filter’s bandwidth is discussed. With help of this approximation, the adaptive notch filter can be parametrized specifically to a given noise spectrum and other requirements. The capability of the parametrization strategy and the adaptive notch filter itself are shown by simulation and measurement.

The evaluation of near-field data can be an effective way to analyze EMI sources. In contrast to antenna measurements, near-field techniques can determine the emitted field without special requirements on the measurement environment. Moreover, critical sources can be found when current distributions can be identified. Therefore, current reconstruction methods for PCB traces were developed. With additional voltage information the termination impedances of the traces can be found. The known phase-less approaches suffers from different limitations, e.g., non-unique reconstruction results. In this paper, the necessary conditions for a unique reconstruction are discussed by investigating simulated phase-less near-field data. Based on these findings, measured near-field data of a PCB trace is evaluated, and the successful retrieval of the phase information is shown. Additionally, reconstructed voltage distributions are presented and compared to measurement data.

Localization of EMI sources can be a challenging task. The next step is often to identify the parameters of the EMI generating structure and find appropriate suppression. In this work, a method is presented to handle such problems by using only a phase-less scan of the electromagnetic near-field. Here, radiating conductor systems are investigated, like traces on a PCB. Using the electric and/or magnetic near-field distribution, the radiating current distribution can be reconstructed. In this paper an approach based on a known trace geometry and electric as well as magnetic field data is presented. When current distribution is known, critical EMI sources can be found. Furthermore, an approach is presented to design virtually a filter concept for a critical EMI source. For demonstration, based on measurement data, an exemplary conductor structure is investigated. It is pointed out that high currents and high local fields do not necessarily lead to a high far-field. For the exemplary conductor structure, critical sources are identified, and it is shown how the needed filter structures can be found.

Immunity failures of safety-critical automotive sensors can often be linked to strong resonances. In traditional approaches to combat the resonance, it is either shifted to other frequencies or attenuated. In this paper, a third way is shown. Every resonance is associated with an eigenmode of the system. If externally excited, the mode may resonate with a certain amplitude. This amplitude is a function of the projection of the system’s excitation onto the spatial distribution of the mode.With the help of a 3D sensitivity analysis, we identify potential geometric parameters that lead either to a reduced excitation of the eigenmode or that lower the impact of the eigenmodes on the target signal.Applying this method to an automotive pressure sensor a significant reduction of the resonance amplitude by a small modification in the sensor layout is achieved.

The automotive wiring harness poses a challenging electromagnetic environment with its extension and small distances between wires. The introduction of high voltage applications and Wide-Band-Gap (WBG) semiconductors in power electronic systems leads to steeper slopes of control signals, e.g. PWM signals. These signals can cause serious coupling to communication wires and reduce the bitrate. As the safety and reliability of communication are essential requirements of new technologies like autonomous driving, immunity of communication systems has to be investigated. This paper shows a theoretical analysis on the impact of recurring disturbances on communication performance caused by wire coupling. To reduce the impact of disturbance, cooperative operating strategies of the power electronic system and the communication system are proposed to avoid serious delays or bitrate reductions. The presented cooperative operating strategy is an adapted access method based on available time-triggered concepts.

In this paper, model-based approaches to control smart power-switches in vehicles are presented and discussed. The proposed methods use thermal cable models as well as the load characteristics to provide not only a cable protection with different switching strategies but also diagnosis functions such as virtual monitoring of thermal aging and dynamic load limits. Those can be implemented on microcontrollers in different levels of complexity depending on the needed accuracy and calculation speed.

Active cancellation can suppress electromagnetic interference (EMI) of clocked systems like power electronic converters. Considering clocked systems that operate stationary over a sufficient time, there are stable harmonics that can be individually suppressed by destructive sine waves. These sine waves can be superposed to create a synthesized wide bandwidth cancellation signal. Adaptive approaches have proven to be very effective to find the right parameters for each sine wave. Bothersome effects, like complex frequency characteristics or delays, can be compensated by appropriate amplitudes and phases. Therefore, this method does not suffer from the same limitations as active techniques with feedback- or feedforward-topologies. If the disturbances are constant over a sufficient time, the parameters for the cancelling sine waves can be found simultaneously or successively. Until now, only the first option has been shown with an adaptive cancelling FPGA system. Since the cancelling logic needed to be implemented for each cancelling sine wave and the resources of any FPGA are limited, the number of suppressible harmonics was limited as well. In this work, this limitation is resolved by a successive approach that enables the application of the method to a very large number of harmonics. The fundamental theory is discussed, and a robust algorithm is presented. A cancellation system is realized and applied to a 48V/12V DC/DC converter (e.g. for automotive applications) to suppress the frequency range of 150 kHz to 30 MHz in regard to the automotive EMC standard CISPR 25.

Automotive sensors need to fulfill severe electro-magnetic compatibility (EMC) requirements. The space available for EMC solutions based on discrete filter elements is limited. Furthermore, direct voltage or current measurements for analysis purposes are difficult. Innovative simulation methods are therefore needed to further understand and develop non-conventional EMC solutions. In this paper an analysis method to extract the dominant coupling path within sensors and to generate minimized electrical equivalent circuits (EEC) using network based sensitivity analysis is presented. In addition, a computational method that indicates the hotspots causing the EMC immunity failures with high resolution is introduced. Consequently, potential geometric and layout optimizations are derived easily. Failures due to small asymmetries are finally analyzed and optimized using an automotive pressure sensor.

In many modern power electronic systems, fast periodically switching semiconductors are utilized for system control and minimizing switching losses. The resulting steep switching waveforms may cause electromagnetic interference (EMI) that is mostly reduced with help of heavy passive filter circuits. One basic idea is to optimize EMC behavior and efficiency of power electronic devices by forming the switching waveforms with regard to steepness, overshoots, ringing and high frequency disturbances. Therefore, optimum control signals have to be found and synthesized. To do so, the nonlinear transmission behavior of semiconductor devices has to be considered. To start with, a basic MOSFET test circuit is regarded in this work. With help of an iterative search algorithm, a control signal is found that fits the MOSFET’s output signal to a desired waveform that optimizes EMI and minimizes switching losses. The capability of this method is shown by simulations and measurements.

Active cancellation of disturbances of power electronic systems is a common method in EMC. Most publications on this topic deal with the cancellation of either common or differential mode disturbances at either the input or the output terminals. In many systems, all disturbance modes of all terminals must be suppressed simultaneously. This is no trivial task since the different injectors for the anti-noise can affect each other. Therefore, a cancellation signal for the input terminals can worsen the noise at the output terminals, or vice versa. Additionally, due to mode conversion, common and differential mode can also interfere. In this work, synthesized cancellation signals are utilized that have already shown a very good performance in the suppression of periodic disturbances since complex transfer functions and delay times can be compensated. For the first time, a multi-port canceller is applied that injects synthesized cancellation signals to reduce the noise at four terminals simultaneously. The canceller enables a characterization of the system and an identification of the mutual coupling between the injectors. From this knowledge, the cancellation circuits can be designed purposefully. Furthermore, the mutual coupling can be respected in the calculation of the cancellation signals. A fundamental theory is described for DC/DC converters and applied to a 48 V/12 V converter in a measurement setup for conducted emissions according to the automotive EMC standard CISPR 25. The effectivity of the method is shown by measurements at artificial networks. The power losses of the cancellation system are estimated.

Automotive sensors need to fulfill severe electromagnetic compatibility (EMC) requirements. To improve the robustness of a sensor in early product development stages, an accurate immunity simulation is essential. Furthermore, a fast and reliable broadband immunity measurement to cover all sensor susceptibilities is necessary.In this paper, a new approach to simulate the digital output values of a pressure sensor in a closed-loop Bulk Current Injection (BCI) procedure is introduced. In addition, a sensor specific measurement method of both high accuracy and short test time is presented. Finally, the simulations are validated with measurements using automotive pressure sensors.

Active gate control of MOSFETs is a common strategy to improve efficiency and/or electromagnetic compatibility (EMC) of power electronic systems. Finding an appropriate control method for specific requirements is no trivial task, and often there is a trade-off between efficiency and EMC. In this paper, a novel method is proposed that utilizes synthesized control signals. With signal synthesis methods, that can be realized affordable in future integrated circuits, signal shapes can be adjusted more or less arbitrarily. Various requirements, e.g. switching waveforms, overall system’s EMC or efficiency, can be aimed at this way. Here, a basic MOSFET circuit is investigated which should generate a specific switching waveform. This waveform shall improve the system’s EMC without significantly affecting the efficiency. The system is developed, characterized and a mathematical approximation is derived that respects the important temperature dependency. In this first demonstration, very low switching frequencies are considered that make the reactive elements of the MOSFET negligible. From the requirements and the system model, a suitable control signal can be derived. Measurement and simulation results show the good performance of the proposed method.

Electromagnetic disturbances from power electronic systems can affect communication networks, especially in the automotive wiring harness with its limited distance between wires. The introduction of Wide-Band-Gap (WBG) semiconductors in power electronic systems enables smaller components and higher efficiency due to higher frequencies and steeper slopes of the PWM control signals. Furthermore, the increasing energy demands lead to a raise of the voltage level up to 48 V. In contrast to high voltage automotive systems with complex shielded cables for EV (Electric Vehicles), unshielded cables are applied in 48 V cabling systems. The use of fast switching power electronic devices in combination with the increased voltage level pose a new challenge on electromagnetic compatibility in automotive environment. This paper shows investigations on the immunity of communication networks under these new conditions. Therefore, measurement and simulative analysis are presented to estimate the potential impact on the reliability of data transmission.

Information on field emissions is required in many applications. Typically, antennas are used for the measurement of the far-field. Antenna measurements suffer from several problems, e.g. the need of large anechoic chambers. Near-field measurements/scans might become an attractive alternative in the future. The far-field can finally be calculated from near-field measurement data. For an accurate calculation, phase and amplitude distributions of the near-fields are needed for all considered frequencies. As phase measurement can be very troublesome, the reconstruction of the phase from phase-less measurement data is highly attractive. In this paper, a method is presented to find the EMI of PCB traces or similar structures with phase-less near-field measurements. In this method, knowledge of the geometry of potential radiating is applied. From this knowledge, boundary conditions can be found for phase estimation. The method is shown in detail and the benefits are discussed on result of reconstructed current distributions and estimations of the far-field.

This contribution presents a new concept for model-based automotive smart fuses, which takes indirectly into account the influence of real environmental conditions such as neighboring cables and local ambient temperatures. The proposed concept is based on a thermal cable model for the standard cable protection and additionally on the measurements at the cable ends and thus enables a short-time overload operation, which can be particularly important in safety-relevant driving situations. The reduction of lifetime of the cable caused by thermal overload is also monitored and used as an additional tripping criterion.

The introduction of 48 V power supply systems into automotive vehicles may lead to critical arcs when a 48 V connection is interrupted (series arc) or shorted to ground or 12 V (parallel arc) and opened again. The high energy dissipation in the arc might damage connectors or even cause fire. The energy dissipation during arc events strongly depend on the power network. In order to understand the arc behavior, a deeper look inside the processes going on during arc faults in typical automotive supply configurations is required. Experimental research on arcs is extensive, and computer simulations are more promising but in the past no appropriate arc models were available. With a new accurate modelling approach complete power network investigations can be done. This paper makes use of the new arc model and analyzes the interaction between the arc and typical power supply systems. Approaches to identify worst-case situations are suggested, both for series and parallel arcs. Furthermore, it is shown, how the influences from the power network on the arc behavior can be utilized in order to suppress arcs in the moment of ignition based on the oscillating circuit properties, or delete arcs through load control.

The possibility of arc faults exists in various technical applications. Hence, arcing has been the subject of many investigations up until today. The upcoming 48 V voltage level creates the necessity to consider the arc event in the automotive environment. In general, an arc can occur anywhere in the wire harness, either as series or parallel arc. The large amount of dissipated power, resulting in extremely high temperatures, leads to the risk of fire. In order to understand the generation of arcs and the conditions needed to extinguish the arc, automotive supply networks simulation is beneficial. Accurate models for the supply components and the arc are required. This paper presents a DC arc behavioural model for network simulations in a 48 V automotive supply system. The arc voltage is modelled by a current controlled voltage source with a complex function with constant parameters. With the help of a state transition diagram, short circuits and open contacts are considered, as well. The model is evaluated in different circuit setups and it is verified by measurements.

The electric propulsion system of modern electric vehicles may generate high magnetic fields in the low frequency range exceeding the thresholds for health protection. Mainly the currents through the three-phase cable system between the inverter and the electric motor are critical. This paper presents an analytic 2D solution for the magnetic fields from an infinite parallel cable system above an infinite plate. The solution considers the permeability, conductivity and thickness of the material. It is based on a fundamental solution of the diffusion equation and a Fourier-series development of the exciting line currents. The presented approach is fast and accurate for investigating the behavior of different cable arrangements and shielding materials. In this paper the shielding effect of vehicular bodies with different electrical properties is investigated. Several methods to reduce the resulting magnetic field are discussed.

Various publications have shown methods to reconstruct the current distribution of a wire system, e.g. of a PCB, by the usage of near-field data. Especially, if there is knowledge about the potential current paths, these methods achieve satisfactory results. This publication presents a novel approach to improve the quality of the reconstruction by application of the transmission-line theory. Additionally, also the termination impedances of a PCB trace can be determined by the approach presented in this work. For demonstration, several PCB-like structures are investigated with the introduced methods. The results are discussed and compared to other methods.

Cancellation of disturbing signals is a common strategy in EMC. In this work, a specialized strategy is developed to cancel the disturbing harmonics of stationary clocked systems. This strategy is refined by an adaptive approach to conveniently find the optimum signals for cancellation. As a special feature of this method, all troublesome effects, like delays or attenuations, can easily be compensated. From a basic theory, two implementation variants are derived: 1) Continuously Adapted Harmonics Cancellation (CAHC) and 2) Previously Adapted Harmonics Cancellation (PAHC). CAHC is implemented on an FPGA-system. The hardware, programming and performance of the utilized FPGA and its peripherals are transparently discussed. The effectivity of the method is demonstrated for a power electronic dc-to-dc converter.

With the electrification of vehicle propulsion systems, shielded cables were introduced for delivering the power from HV-battery to inverter and/or from inverter to three-phase motor. On the one hand the shield should improve EMC behaviour, on the other hand the shield should protect passengers and service staff from the high voltage. While in typical communication application of shielded cables the shield carries the return current from the inner conductor and the current sum is zero, the automotive power cable employs a second shielded, and, for three phase applications, a third shielded cable, for the return currents. There is no current injection into the shield. Shield currents are mainly induced by inductive coupling. Knowing the shield currents is essential for evaluating the common mode current and thus the relevant fields caused by a cable configuration. In this paper an analytic approach for estimating the current distribution in and the fields from a shielded cable system for EV for low frequencies is presented. With this method typical systems are calculated and discussed regarding the common mode currents and the magnetic fields.

As a new voltage level, 48 V has been introduced to automotive power supply systems. As a consequence, new critical phenomena, arcs, may arise. These arcs can cause serious damages, even fire. In this paper, arcs in 48 V automotive power supply systems are investigated and a full model is developed and parameterised. Electrical models are required to clarify the connection between the arc characteristics and the power net components itself. Conditions promoting arcs and inhibiting arcs can be developed. Model based arc detection strategies demand for accurate models, too. Transient phenomena as well as operation points are considered. Additionally thermal investigations of arcs are carried out to evaluate the severity of different arcs. Methods for burn time prediction based on dissipation power of arcs are presented.

This paper discusses the limitations of power line communication (PLC) in vehicles, regarding system loads, transceiver coupling circuits and cable topology. Firstly, ECU input impedances were analyzed to obtain typical termination load conditions in modern vehicle power supply systems. Coupling circuits and cable harness topologies for the power distribution network were proposed, as well. Then, the common applied structure (tree topology) from modern vehicles was analyzed. EMC is considered by analyzing immunity and emission in vehicle. Three exemplary topologies of in-vehicle power supply system were analyzed. It has shown that ECU number and number of star points have significant influence to data transmission in PCL. Also, worst and best conditions for data transmission has been found based on retrieved channel characteristics and signal to noise ratio (SNR) approximations considering that the noise limit level in automotive power supply system equals to CISPR25 conducted emission limits.

This work deals with the adaption of PWM frequencies to a chosen AM or FM broadcast channel in a vehicular application. To do so, the radio passes the information of the current receive channel to EMI sources that utilize PWM signals. By this feedback loop, the switching harmonics can be shifted in such way, that the respective receive channel is free of disturbances. For the adaption, two different strategies are derived, analyzed and applied: Harmonics shifting and zero harmonics shifting. These strategies prove to be viable options that help to fulfill vehicle-internal EMC demands that mostly are much stricter than legal regulations and international standards.

Continuously increasing requirements for the vehicles' on- board system in terms of autonomous driving functions lead to new power network topologies. One promising concept is the usage of a 12 V dual battery system consisting of a lead-acid- and a lithium-ion-battery instead of a single lead-acid battery. The maximum system peak power depends on the current distribution between the two batteries, which cannot be controlled. This paper presents a new estimation method to predict the current distribution and thus the maximum system power. Estimation methods for standalone battery systems are compared to the new dual battery estimation method and vehicle measurements.

Failures in digital devices can be caused by ESD-pulses coupled directly or indirectly to input pins. Weak pulses will not destroy a device but can be interpreted as logical signals (ESD soft failure). In this paper, a modelling and characterization methodology for a microcontroller input is proposed. With this model the ESD soft failure behaviour can be simulated. First a measurement setup for characterization of input behaviour was developed and applied to a commonly used microcontroller. For the digital input an RC model approximation is used and related parameters are extracted. SPICE simulations have been performed and results have been compared with the measurements. It could be shown that the RC model can predict quite well the ESD soft failure behaviour.

In automotive radiated emission testing, as specified in CISPR 25, the absorber lined shielded enclosure (ALSE) method is commonly used. This requires an expensive chamber. Based on the observation that the dominating coupling is capacitive at frequencies below 30 MHz, the emission tests often suffer from low reproducibility. In order to predict emission in an alternative test method, a Huygens's principle based field prediction method is presented in the paper. This method only requires a set of near-field measurements along a line above the metal table of the CISPR 25-setup. The uncertainties of the predicted fields at the measurement antenna location is reduced, because the near-field measurements dramatically minimize the influences from nearby objects. The higher field strength close to the cable also improve the signal to noise ratio with respect to external noises such that the method can be applied without the use of a shielded chamber. The proposed method defines an open Huygens's surface located in front of the cable harness and the equipment under test (EUT). First, the near-field measurements are conducted using an electrically-short monopole field probe, and second, the field distribution along the whole Huygens's surface can be found using the measured data and applying an appropriate extrapolation function over the Huygens's surface. The field distribution on this surface is finally used to calculate the electric field at the antenna location.

This paper investigates instrumentation effects that may limit the usefulness of pre-compliance bench-top test methods for e.g. CISPR 25 radiated field measurements. Here the radiated fields are dominated by common-mode currents along the test cable bundle especially when the frequency is below several hundred MHz. From a known current distribution, fields can be computed. The currents can be measured using current probes with measurement instruments like oscilloscopes or spectrum analyzers (SAs). However, because of the low CISPR limits, very small currents (amplitude and phase) need to be measured. In this paper, as first step, the current values that lead to emissions at the CISPR limit are determined using method of moment (MoM) simulations. For analyzing the practical sensitivity of typical current measurement instruments, the noise figures of oscilloscopes and SAs are approximately measured and the compete measurement system is optimized with respect to probe selection and pre-amplification. It is shown that oscilloscopes and SAs achieve similar sensitivities, and both having noise figures in the range of 15–25 dB without pre-amplification. By setting corresponding fast Fourier transformation (FFT) parameters it is possible to obtain the same bandwidths in an oscilloscope as in a SA for the bandwidths typically used in electromagnetic interference (EMI) measurements. Further, oscilloscope-based phase measurement is explained. The noise induced errors are shown for the magnitude and phase indicating a lower minimal detectable signal of about −25 dBµA for less than 15° phase error.

Failures in digital devices can be caused by ESD-pulses coupled directly or indirectly to input pins. Weak pulses will not destroy a device but can be interpreted as logical signals (ESD soft failure). In this paper, a modelling and characterization methodology for a microcontroller input is proposed. With this model the ESD soft failure behaviour can be simulated. First a measurement setup for characterization of input behaviour was developed and applied to a commonly used microcontroller. For the digital input an RC model approximation is used and related parameters are extracted. SPICE simulations have been performed and results have been compared with the measurements. It could be shown that the RC model can predict quite well the ESD soft failure behaviour.

A small-signal model of an automotive system-level bulk current injection (BCI) setup developed with a generalized accurate method shown in the previous publication [3] is verified on a case study with a demonstrator EUT module. The work utilizes an equivalent circuit modelling approach for the floating ungrounded EUT board and a macromodel for an active DUT IC. The simulation-based prediction of the BCI test results using an IC failure threshold and a small-signal simulation of RF levels at floating EUT module under BCI tests is shown. Due to high accuracy and detail of the BCI setup model, the prediction also shows very good correlation to real measurement data, both qualitatively and quantitatively, up to 1 GHz.

Nonlinear voltage sensitive protection elements, e.g. Multi-Layer Varistor (MLV) or Transient Voltage Suppressor (TVS) are useful to protect IC pins from ESD on System Level. Such elements might exhibit a significant voltage overshoot for fast transients. This work describes a combined time and frequency domain characterization method and its application to an MLV. Impedance measurements with VNA at different DC-bias points are used for model identification and parameterization. The static nonlinear IV-behavior of nonlinear model part at higher voltages and currents is extrapolated with a TLP IV-curve. The model is successfully validated with ESD pulses in time domain. The transient behavior including the occurring voltage overshoot can be reproduced with high accuracy.

In this paper, immunity of commonly employed modulation schemes for low data rate transmission over power line (PLC) are investigated. Transmitter and receiver models for Amplitude Shift Keying (ASK), Frequency Shift Keying (FSK) and Binary Phase Shift Keying (BPSK) are implemented. Virtual automotive EMC tests, including Direct Power Injection (DPI), Bulk Current Injection (BCI) and plane wave field coupling (ALSE) were performed to investigate the immunity of the modulation schemes. Furthermore, selected pulse disturbances were tested. For method validation DPI measurements of a real PLC transceiver for automotive applications were carried out and failure behavior was compared to the virtual DPI test results. The pros and cons are discussed.

In this work, a novel approach to the modeling of ESD protection elements multi-layer varistors (MLV) is presented. Based on measurements of the static I-V-characteristics, an approach similar to the EKV model is used instead of the known ideal I-V-characteristics in the threshold voltage region. Additionally, an equivalent circuit for the representation of the impedance frequency response (especially its low- and mid-frequency behavior) is derived from impedance measurements depending on the varistor's DC operating point. The established model includes frequency depending resistances known from skin effect modeling.

In this paper the low frequency shielding behavior of shielded high voltage cables for electric vehicles is analyzed using analytical methods. First the basic theory on the operational modes and modeling of cables is presented. Measurements and numerical simulations are done to verify the models. The powertrain of an electric vehicle is investigated using the simulation models. A parametrical study determines the influence of parameters such as height and distance of the cables and gives information for an EMC compliant layout. The magnetic fields for different cable setups are calculated and compared with values from health protection standards.

Simulations of automotive immunity test setups are often used to analyze the systems at early design stages and therefore to predict and to avoid failures in advance. Accurate models for different setup structures are needed to evaluate the RF coupling levels to DUTs. In this work an accurate measurement based approach to build models for passive test setup structures is proposed. These models are applied to estimate the interfering RF current levels at DUT inputs. A measurement-based modeling procedure for BCI coupling to a cable harness and for incident field coupling to a cable harness is presented. The proposed methods reproduce the existing test setups in a simulation environment and therefore accelerate and simplify further investigations. In order to ascertain the validity of the approach, simple test structures with different termination impedances are investigated.

The transmission of automotive communication-signals in mass production is based mainly on electrical cables used in topologies which do not meet technical schoolbook requirements perfectly. For evaluating their signal quality and their communication robustness time-domain based simulation tools are essential. One of the key elements hereby is an adjustable cable model. Unfortunately real cables show frequency-dependent behaviours which are not covered by time-domain simulation tools usually. The paper points out some summarizing results of various projects which enable a workflow beginning with (noisy) cable measurements going via approximation procedures up to frequency and time domain qualified models.

Development of accurate system models of immunity test setups might be extremely time consuming or even impossible. Here a new generalized approach to develop accurate component-based models of different system-level EMC test setups is proposed on the example of a BCI test setup. An equivalent circuit modelling of the components in LF range is combined with measurement-based macromodelling in HF range. The developed models show high accuracy up to 1 GHz. The issues of floating PCB configurations and incorporation of low frequency behaviour could be solved. Both frequency and time-domain simulations are possible. Arbitrary system configurations can be assembled quickly using the proposed component models. Any kind of system simulation like parametric variation and worst-case analysis can be performed with high accuracy.

Complex multi-voltage automotive power supply systems are difficult to optimize. In this paper a simulation-based method to optimize multi voltage power supply systems is presented. With an electrical-thermal wire model the ampacity and the voltage drop of a cable can be determined. With these criteria cables of the power supply system can be dimensioned. By extending the electric-thermal models with functions defining costs, weight and space of the wires and DC/DC-converter models evaluation and optimization of multi-voltage vehicle systems is possible.

FlexRay is an important communication network for automotive systems and the de-facto standard for in-vehicle safety and time-critical applications. High reliability and self-diagnosis are indispensable. Since bus networks can be affected during their whole lifetime by permanent failures on the transmission wires, the interest on failure detection is increasing. In this paper the static and dynamic performances of common automotive failure detection methods are analyzed for a FlexRay controller. A new mechanism for the peculiar symmetrical structure of FlexRay is proposed and compared with the more known ones. It permits an improvement of the static and dynamic performances. The analysis is based on analytical computations and numerical Spectre-simulations.

In automotive EMC ALSE method, specified in CISPR 25, is commonly used for emission measurements. Components or modules are required to be connected with a test cable bundle for evaluating radiated emissions. The radiation is often mainly dominated by the common mode current along the cable bundle. In order to predict radiated emissions from setups according to ALSE method, without using a large anechoic chamber, this paper presents an alternative and innovative method. The presented approach determines radiated fields from a cable bundle without phase information. It is only based on the amplitude of common mode current from phaseless measurements using a RF current probe. Firstly, radiation model of a cable bundle is simplified to a single equivalent transmission line (TL) according to the mode analysis of multiconductor transmission line (MTL) theory. Then an optimization procedure based on trust-region-reflective (TRR) method and multi-start point algorithm is used to determine the common mode parameters of the equivalent TL by fitting to the measured current amplitude. The phase of common mode current, therefore, is retrieved through optimized TL parameters. Finally, the radiated fields are straightforwardly evaluated by elementary dipoles approximation of the cable bundle. The proposed approach is verified by numerical analysis of different cable bundle models and measurements. The stability and feasibility to evaluate radiated emissions from a cable bundle could be shown.

Accurate and flexible modeling of field coupling from ESD sources to cables or PCB traces (indirect ESD) is important for immunity estimations. Accurate circuit models can be obtained by applying approximations techniques to measurement data in frequency domain. In this paper an accurate ESD generator model is extended to model ESD coupling behavior for the ESD generator to a cable setup. The new model can be used for simulation of arbitrary load conditions, for both direct and indirect discharge. The model represents the individual characteristics of an ESD generator without applying complex 3D field simulation. It allows computation of the coupled voltages over linear or nonlinear termination using a circuit simulator.

This paper deals with different methods to find systematically critical coupling configurations. A critical coupling configuration can appear between a cable and an antenna or cables for data and power transmission. In the later case the minimum distance between the cables or the maximum length for placement in one cable bundle must be determined. One option to find the critical parameters can be standard circuit simulation. In this case the simulation has to be repeated several times. A better approach is using a direct inverse method based on the Modified Nodal Analysis (MNA). Both approaches are discussed in this paper and critical coupling parameters are determined for several configurations.

Considering the ongoing increase of the amount of electronic components in vehicles the optimization of the power network is essential. To optimize the cable harness the ampacity, the voltage drop and the temperature of every cable have to be determined. In this paper stationary and transient ways of modeling cables are presented and compared. All simulation models are created in VHDL-AMS and validated with several measurements. The benefit of exact cable models is the possibility to analyze and optimize the cable harness in an early stage of development. A method to generate a simulation model of a power supply system is presented. The complete benefit of the method is illustrated with a simplified model of a typical automotive supply cable harness. The simulation results of the model are compared to vehicle measurements.

Automotive bus systems like FlexRay or CAN have to provide correct functionality for safety critical applications under various circumstances. In addition many parameters can influence signal integrity. To ensure correct behaviour under all given conditions, simulation based analyses are performed. In this article it is presented how simulation models have been developed, automated workflow and signal analysis have been implemented and parameter search methodologies have been chosen and adapted to provide tools for validation of bus system topologies.