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Abstract A 1 × 4 magneto‐electric dipole (ME dipole) antenna array for 77 GHz automotive radar is proposed. The ME dipole is fed by a fork‐shaped microstrip line coupling through a dog‐bone slot. To meet the requirements aimed at automotive radar applications, the beamwidths of the proposed antenna are well‐designed. Specially, a method of adding passive elements on both sides of the array is proposed to increase the 3 dB beamwidth from ±34° to ±52° in azimuth. Additionally, in elevation, a 3 dB beamwidth of ±10° is achieved by designing the spacing between array elements. Moreover, based on low‐loss printed circuit board substrates, radiation efficiency of the proposed array can reach approximately 90% at 77 GHz. Furthermore, a 4 × 4 array is established by arranging four 1 × 4 subarrays spacing 1.95 mm (half a free‐space wavelength at 77 GHz) to study the interactions between subarrays for multiple input multiple output scenarios. A 1 × 4 and a 4 × 4 antenna prototypes are fabricated and measured to validate the correctness of this design. The results show that the proposed antenna is an eligible candidate for the medium‐ and short‐range automotive radars.

The integrity of the 12Vdc power distribution system on a vehicle is essential to guarantee continuous power supply to safety-relevant consumers. Safety-relevant consumers are critical loads, for example, electric power steering, braking systems with functionalities like Anti-Lock Braking or Electronic Stability Control, and autonomous drive systems. To prevent insufficient power supply for safety-relevant consumers due to an increased wiring harness resistance, a novel diagnostic approach is developed to determine the condition of the power distribution, especially the electrical resistance. The influence of measurement errors and bus commutation on the estimation is investigated by using a simulation. By using the diagnostic, a resistance determination in the milliohm range with a standard deviation of σ=0.3mΩ can be achieved under realistic conditions. This ensures that failures in the wiring harness can be identified, avoiding cascading effects and minimizing recalls. Compared to the state of the art, redundancies, costs, and weight can be saved with the proposed diagnostic system based on electrical resistance estimation.

To cope with the megatrends electrification, automated driving, and connectivity, new functionalities and electric and/or electronic systems must be developed, which require a safe power supply. This leads to increased functional safety requirements for the power supply system, particularly regarding availability. Fault tolerance measures can be implemented to comply with a safety goal (SG) specifying a safety-related availability requirement. To verify an architecture concerning the residual risk of an SG violation, several quantitative target values are provided in ISO 26262. This technical elaboration presents a systematic and holistic approach how to gain benefit in the quantitative evaluation from cyclic safety mechanisms (SMs)– in a fault tolerant item– which have a fault handling time interval (FHTI) longer than the fault tolerant time interval. Modelling cyclic SMs only based on conventional AND-gates is not sufficient. Instead, the fault sequence is differentiated to enable ISO 26262-compliance. Within this paper, an innovative approach including its mathematical background is presented how cyclic SMs can be modelled in a fault tree analysis– with focus on multiple-point faults. The results are verified by a Monte-Carlo-Simulation. Besides the scalability of the approach regarding the number of considered cyclic SMs, the relevant FHTI of each cyclic SM can be considered in a traceable and comprehensible manner.

To cope with the megatrends electrification, automated driving, and connectivity, new functionalities and E/E systems must be developed, which require a safe power supply. This leads to increased functional safety requirements for the power supply system, particularly regarding availability. Fault tolerance measures can be implemented to comply with an SG specifying a SaRA requirement. In this case, EO may be necessary to reach a defined safe state. However, there is some ambiguity in ISO 26262 regarding the necessary integrity with which the EO shall be implemented – this becomes in particular obvious in the case of warm redundancy. According to ISO 26262, the EO is entered once the failure of an element is controlled by an explicit fault handling, i.e., prevented from violating an SG, and the remaining ASIL capability of the item after the failure is lower than the required ASIL capability for the allowed VOS. However, in the context of warm redundancy, the EO can be automatically entered in the case of an element failure without an explicit fault handling. The objective of this paper is to transfer the concept of EO, as defined in ISO 26262, to warm redundancy use cases because warm-redundant power supply systems have a high level of market penetration. Besides a detailed evaluation of time dependencies, new guidelines concerning the required systematic integrity for SMs implementing EO are provided.

The automotive industry is currently driven by the megatrends electrification, automated driving, and connectivity. To cope with these trends, new functionalities and electric and/or electronic systems must be developed, which require a safe power supply by the power supply system. This leads to increased functional safety requirements for the power supply system, particularly regarding availability. Fault tolerance measures can be implemented to address a safety goal specifying a safety-related availability requirement. In this case, emergency operation (EO) may be necessary to reach a defined safe state. The definitions and examples provided in ISO 26262 focus on cold redundancy, whereby the backup system is not engaged during nominal operation. The objective of this paper is to evaluate EO in the context of ISO 26262 in detail and map the results to an exemplary power supply system architecture implementing cold redundancy. In general, the EO is considered to be free from unreasonable risk even though the actual automotive safety integrity level (ASIL) capability of the item is lower than the initially specified ASIL rating for the hazard due to its timing restrictions. To determine the maximum permissible duration of EO, not just random hardware faults shall be considered; additionally, systematic effects shall be considered. Furthermore, an EO may be entered due to transient faults potentially causing temporary EOs – introducing the necessity of an EO recording, e.g. by accumulating the time of all temporary EOs.

The automotive industry is currently driven by the megatrends electrification, automated driving and connectivity. To cope with these trends, new functionalities and electrical and/or electronic (E/E) systems need to be developed and deployed. Independent of the implementation of E/E systems, their power input shall be ensured by the power supply system as a shared resource – leading to increased functional safety requirements for power supply systems. If the loss of an item’s functionality can lead to a hazardous event, a safety goal (SG) specifying a safety-related availability (SaRA) requirement is derived. Thereby, switching to passive mode typically cannot be considered a safe state. To address an SG specifying a SaRA requirement, fault avoidance, fault forecasting and/or fault tolerance measures can be applied. In the case of fault tolerance measures implemented by redundancy, which leads to fail-active behavior, the performance of the backup system during nominal operation and after the first fault can be further refined. In this study, SaRA in the context of ISO 26262 is evaluated in detail and mapped to an example of the power supply domain.

At the vehicle powernet level, technical safety mechanisms, e.g., smart switching modules, mainly operate in a discrete-time or cyclic manner. In accordance with the functional safety standard ISO 26262, safety-related E/E systems require a safety validation process. Therefore, evidence of the effectiveness of technical safety mechanisms shall be made available. Particularly for cyclic safety mechanisms (cyclic – regarding their fault handling performance), this is an open issue. In this regarding, a novel modeling approach for cyclic safety mechanisms is introduced to provide evidence of their effectiveness. Thus, cyclic diagnoses, e.g., vehicle start-up checks, or new dedicated measures could be utilized in the quantitative validation of residual faults. The novel approach enhances the current state of research in a way that makes the interpretation of a piecewise constant failure rate irrelevant. In addition, this approach is not solely based on the exponential distribution; therefore, it is universally adaptable, and it is demonstrated for the use case of alternating safety mechanisms. This degree of freedom is accompanied by more conservative quantitative results in comparison to those obtained in recent studies. Nevertheless, the current state-of-the-art method totally excludes the evaluation of cyclic safety mechanisms because of a lack of evidence of effectiveness. This elementary concept is based on the derivation, elaboration, and separation of time dependencies in a safety scenario while extracting and evaluating the partial system states with effective continuous behavior. The derived mathematical model and its approximation are based on fundamental statistics and are indicated as the final recommended cyclic approach.

The relevance of safety applications within the automotive industry is increasing continuously, e.g. due to vehicle automation and decreasing relevance of mechanical backups. To cope with these trends, the power input of safety-related electrical and/or electronic systems needs to be ensured by the power supply system – leading to increased functional safety requirements. Compliance with ISO 26262 will be more in focus in the future. Currently, the compliance with ISO 26262 may be used to argue the state of the art focusing on product liability – however, it will become mandatory for homologation. Thereby, the power supply system is a crucial point since faults of the power supply system are currently the major contributor for vehicle breakdowns with increasing tendency. So far, there is no standard approach within the automotive industry how to ensure functional safety for power supply systems. To fill this gap, this technical elaboration evaluates functional safety with focus on power supply systems development. Hence, guidelines on how to apply the ISO 26262 are provided based on discussions within the automotive industry and research institutes. The focus is on the concept phase, i.e. item definition, hazard analysis and risk assessment, and the functional safety concept. The functional safety concept is based on a structured hierarchical breakdown to systematically derive safety requirements from the item level down to the power supply system level. The essential safety requirement – beside the safe power feed and safe power distribution – is to assure the freedom from interference between the safety and non-safety relevant components.

The modern automobile industry is rapidly shifting toward the era of self-driving cars. Due to rapid technological development, many mechanical parts in automobiles have been switched to electronic devices. Therefore, the proportion of electronic devices in modern cars is increasing. Even though many parts have been replaced by electronic devices, vehicles still require the periodic maintenance not only for mechanical parts, but also for automotive electronics. To guarantee the high reliability of automotive Application-Specific Integrated Circuits (ASICs), automotive chips are tested during manufacturing for functional and structural defects. Moreover, automobile chips are also tested using several in-field diagnostic techniques (e.g., online Built-In Self-Test (BIST), Software-Based Self-Test (SBST)) while the chips are operating. By using these in-field diagnostic techniques, functional and structural defects in automotive ASICs, which occur in the early-life cycle and normal operation, can be detected. However, automotive semiconductor devices still require testing for aging-induced defects and soft errors to prevent critical functional failures. Moreover, aging-induced defects are hard to detect with conventional in-field diagnostic techniques which is based on BIST techniques. Thus, this work presents a secure Controller Area Network (CAN) -based Test Access Mechanism (TAM) for aging defect diagnosis with efficient soft-error resilient scan cell design for automotive ASICs. The proposed TAM incurs area overhead of 6% to 9% depending upon the selection of mode identification. Further, the proposed Aging monitoring and Soft Error Resilience Flip Flop (ARFF) incurs 22% less area and power as compared to separate implementation of the Built-In Soft Error Resilience (BISER) and the Early Capture Flip Flop (ECFF).

We combined adaptive filters associated with power estimators to characterize the knock signal, obtained from a knock sensor, in an internal combustion engine. The filters were implemented using the automotive model-based design methodology, and the resulting software was embedded into hardware for a real-time evaluation of the proposed solution. The knock signals could be qualitatively identified in real-time, and thus have the potential to aid in the management of flexible-fuel engines. This approach has an extensive range of applications within the automotive industry, since it can be implemented within any model-based control strategy. For example, this methodology can be applied in commercial ECUs, currently used in most vehicles for knock detection, by simply eliminating an internal, dedicated, integrated circuit for knock identification, or by serving as a redundancy device (i.e: for safety purposes). Finally, this methodology can identify the knock signal, obtained from a knock sensor, just by using an algorithm implemented in the ECU's processor, which we show is identifiable in real-time.

This paper deals with developing and implementing a bidirectional galvanically isolated on-board charger of a high-power density. The power density of the new charger was 4 kW/kg and 2.46 kW/dm3, and the maximum efficiency was 96.4% at 3.4 kW. Due to the requirement to achieve a high-power density, a single-stage inverter topology was used. Regarding switching losses, due to the topology of the circuit with so-called hard switching, the switching frequency was set to 150 kHz. A laboratory prototype was built to verify the properties and operating principles of the described charger topology. The on-board charger has been tested in a microgrid test platform. Due to the parasitic properties of the transformer and other electronic components, overvoltage with subsequent oscillations occurred on the primary side of the transformer and damped resonance on its secondary side. These parasitic properties caused interference and especially voltage stress on the semiconductor elements. These undesirable phenomena have been eliminated by adding an active element to the charger topology and a new transistor control strategy. This new switching control strategy of transistors has been patented.

This article proposes a cost efficient and easy to implement frequency stabilization method orientated toward communication systems operating in an extensive temperature range, as the automotive or the aerospace applications. The proposed solution uses off-the-shelf components and it is optimized for very low power consumption. The novelty of this article is represented by the introduction of the barium strontium titanate capacitor for quartz crystal oscillator active frequency stabilization. After the design was completed, the performances were evaluated and compared to the ones of the uncompensated oscillator. Experimental results confirmed the suitability of the proposed design, achieving 35 times better frequency stability within variable temperature conditions, whereas the power consumption is maintained below 6mW.

This article presents a synchronous rectification scheme using a six-phase Lundell alternator and a bespoke MOSFET-based active rectifier. The control of the alternator-rectifier system is divided into the hysteresis DC-link voltage control and the switching pattern algorithm. The first allows to keep the DC-link voltage at the required 14V level, while the latter reproduces the same switching pattern as that of a passive rectifier. The system is tested at three different speeds and the results are compared against the body diodes of the MOSFETs in the active rectifier. The harmonic analysis of the generated waveforms indicates the capability of the control algorithm to generate the same switching pattern of a passive rectifier. Finally, the efficiency measurements illustrate a significant efficiency improvement using a synchronous rectification scheme and MOSFETs with low on-resistance.

Dynamic modelling of electronic power steering (EPS) systems is an essential part of vehicle dynamics simulation during the development process in automotive industry. Most of existing models focus on mechanical or driving-comfort issues (i.e. steering ripple analysis) but do not consider precise modelling of the power consumption of the system. However, correct dimensioning of board net components requires accurate predictions of the system's power demand as early as possible. In order to fill this gap, this article presents both modelling and parameter identification of a steering system with a simple mechanical module and a detailed representation of the electrical subsystem. Accuracy of the developed modelling approach is validated against test bench and vehicle measurements.

This study presents a 30 kW, six-phase dual-interleaved buck-boost converter which uses an interphase transformer together with six buck-boost switching arms hard switched at 75 kHz for electric/hybrid vehicle applications. Parameters and construction details of the interphase transformer and common inductors are provided together with a description of the selection of semiconductor devices. Weight, power losses, and temperature rise are evaluated at rated power conditions showing experimental results with a 7 kW/kg gravimetric power density achieved with the converter prototype.

This paper focuses on the driving steering load cycle stress-strain, shake, and transient temperature profiles in relation to failure in an automotive electric power steering (EPS) system. A compact EPS control system model was applied to construct a lookup table for the device power loss calculations. The lookup table was used to obtain the full electrothermal profile of a vehicle EPS system converter. An accurate thermal model was introduced using FLOTHERM software and compared with the results from EPS device temperature testing. The transient junction temperature profiles of the device were studied based on the operational cycles of the vehicle EPS system. Finally, an efficient rainflow cycle counting method was introduced to obtain the statistic random transient thermal stress cycles. Miner's rule was also explored, and the relationship between the accumulated thermal stress damage and material fatigue was used to predict the converter's reliability.

This paper presents the development process of a robust and ROS-based Drive-By-Wire system designed for an autonomous electric vehicle from scratch over an open source chassis. A revision of the vehicle characteristics and the different modules of our navigation architecture is carried out to put in context our Drive-by-Wire system. The system is composed of a Steer-By-Wire module and a Throttle-By-Wire module that allow driving the vehicle by using some commands of lineal speed and curvature, which are sent through a local network from the control unit of the vehicle. Additionally, a Manual/Automatic switching system has been implemented, which allows the driver to activate the autonomous driving and safely taking control of the vehicle at any time. Finally, some validation tests were performed for our Drive-By-Wire system, as a part of our whole autonomous navigation architecture, showing the good working of our proposal. The results prove that the Drive-By-Wire system has the behaviour and necessary requirements to automate an electric vehicle. In addition, after 812 h of testing, it was proven that it is a robust Drive-By-Wire system, with high reliability. The developed system is the basis for the validation and implementation of new autonomous navigation techniques developed within the group in a real vehicle.

In this study, we designed and implemented a smart junction box (SJB) that was optimized for supplying power to low-voltage headlights (13.5 V) in electric vehicles. The design incorporated a number of automotive semiconductor devices, and components were placed in a high-density arrangement to reduce the overall size of the final design. The heat generated by the SJB was efficiently managed to mount an Intelligent Power Switch (IPS), which was used to power the headlights onto the printed circuit board (PCB) to minimize the impact on other components. The SJB was designed to provide power to the headlights via pulse width modulation to extend their lifetime. In addition, overload protection and fail/safe functions were implemented in the software to improve the stability of the system, and a controller area network (CAN) bus was provided for communications with various components in the SJB as well as with external controllers. The performance of the SJB was validated via a load operation test to assess the short circuit and overload protection functions, and the output duty cycle was evaluated across a range of input voltages to ensure proper operation. Based on our results, the power supplied to the headlights was found to be uniform and stable.

This paper presents an experimental system for remote communication between road users and traffic signs. Implemented solution consists of two modules: a transmitter (traffic sign), including novel system for remote waking-up by the passing vehicle with use of the quasi-passive (biased) diode detector circuit, and a receiver (vehicle), which is responsible for wake-up signaling and interpreting received messages. Both modules use Wi-Fi protocol operating in 2.4 GHz ISM band for sending data, and OOK signaling in 868 MHZ ISM band for sending wake-up signals. The paper provides theoretical analysis, description of design challenges and chosen solutions, and finally, laboratory measurements as well as the results of tests conducted in the systems’ target environment with a moving vehicle, confirming correct operation of the system.

The special issue “Energy Storage Systems and Power Conversion Electronics for E-Transportation and Smart Grid„ on MDPI Energies presents 20 accepted papers, with authors from North and South America, Asia, Europe and Africa, related to the emerging trends in energy storage and power conversion electronic circuits and systems, with a specific focus on transportation electrification and on the evolution of the electric grid to a smart grid. An extensive exploitation of renewable energy sources is foreseen for smart grid as well as a close integration with the energy storage and recharging systems of the electrified transportation era. Innovations at both algorithmic and hardware (i.e., power converters, electric drives, electronic control units (ECU), energy storage modules and charging stations) levels are proposed.

Taiwan's semiconductor industry has had a profound influence on both domestic economics and the global IT industry. To enhance its competitiveness and expand its global impact, the Taiwan government commenced the National Program for Intelligent Electronics (NPIE) in 2011 to promote technological innovation of medical electronics, green electronics, vehicular (car) electronics, conventional computer, communication, and consumer electronics, the so-called “MG+4C” applications. The government allocated a budget of $430 million over 5 years to facilitate technology development, advanced research, talent cultivation, industry promotion, and international collaboration. By coordinating with government agencies, research institutions, universities, and corporations, the NPIE develops an integrated framework of academia and industry in Taiwan. It also emphasizes the enhancement of product verification, regulations, and participation in international alliances and standards. By transferring academic results to industry in emerging MG+4C applications, it is expected that the NPIE will contribute to the global semiconductor community, energize Taiwan's IC industry, and create innovative products and intelligent systems for better life and better environment.

This paper experimentally demonstrates the stray-field robustness capability of a novel Hall-based rotary position sensor concept (Huber, S., et al, 2018). The sensor targets safety-related automotive applications, for example powertrain and power steering. In these applications, the safety requirement specifies a maximum stray-field induced error of 0.4°. Therefore, the robustness in corner cases needs to be assessed. We demonstrate the stray-field immunity in multiple corner cases for temperature from −40 °C up to 160 °C and over lifetime. The impact of a uniform 5 mT stray field over all conditions (3σ) is shown to be less than 0.25°. The fully-integrated automotive-qualified sensor is implemented in a 0.18-μm CMOS technology, and achieves 0.7° of angular accuracy.

Problems occurring during motor-vehicle juridicial examination in determining of the speed of vehicles at the time of accident are stated in the given article. The method of vehicles speed determination by means of the studing the vehicle’s electronic control unit equipped with the system of passive safety additional means is offered.