Journal papers

Scamarcio, A., Gruber, P., De Pinto, S. and Sorniotti, A., 2020. Anti-jerk controllers for automotive applications: A review. Annual Reviews in Control.

Anti-jerk controllers, commonly implemented in production vehicles, reduce the longitudinal acceleration oscillations transmitted to the passengers, which are caused by the torsional dynamics of the drivetrain during torque transients. Hence, these controllers enhance comfort, drivability, and drivetrain component durability. Although anti-jerk controllers are commonly implemented in conventional production internal-combustion-engine-driven vehicles, the topic of anti-jerk control has recently been the subject of increased academic and industrial interest, because of the trend towards powertrain electrification, and the distinctive features of electric powertrains, such as the high torque generation bandwidth and absence of clutch dampers. This paper reviews the state-of-the-art of automotive anti-jerk control, with particular attention to control structures that are practically implementable on real vehicles. The survey starts with an overview of the causes of the longitudinal vehicle acceleration oscillations that follow abrupt changes in the powertrain torque delivery. The main body of the text reviews examples of anti-jerk controllers, and categorizes them according to the adopted error variable. The ancillary functions of typical anti-jerk controllers, e.g., their activation and deactivation conditions, are explained. The paper concludes with the most recent development trends, and ideas for future work, including possible applications of model predictive control as well as integration of anti-jerk controllers with autonomous driving systems and other vehicle control functions.

Shao, L., Karci, A.E.H., Tavernini, D., Sorniotti, A. and Cheng, M., 2020. Design approaches and control strategies for energy-efficient electric machines for electric vehicles—A review. IEEE Access, 8, pp.116900-116913.

The market penetration of electric vehicles (EVs) is going to significantly increase in the next years and decades. However, EVs still present significant practical limitations in terms of mileage. Hence, the automotive industry is making important research efforts towards the progressive increase of battery energy density, reduction of battery charging time, and enhancement of electric powertrain efficiency. The electric machine is the main power loss contributor of an electric powertrain. This literature survey reviews the design and control methods to improve the energy efficiency of electric machines for EVs. The motor design requirements and specifications are described in terms of power density, efficiency along driving cycles, and cost, according to the targets set by the roadmaps of the main governmental agencies. The review discusses the stator and rotor design parameters, winding configurations, novel materials, construction technologies as well as control methods that are most influential on the power loss characteristics of typical traction machines. Moreover, the paper covers: i) driving cycle based design methods of traction motors, for energy consumption reduction in real operating conditions; and ii) novel machine topologies providing potential efficiency benefits.

Tavernini, D., Vacca, F., Metzler, M., Savitski, D., Ivanov, V., Gruber, P., Hartavi, A.E., Dhaens, M. and Sorniotti, A., 2019. An explicit nonlinear model predictive ABS controller for electro-hydraulic braking systems. IEEE Transactions on Industrial Electronics, 67(5), pp.3990-4001.

This paper addresses the development and Hardware-in-the-Loop (HiL) testing of an explicit nonlinear model predictive controller (eNMPC) for an antilock braking system (ABS) for passenger cars, actuated using an electro-hydraulic braking unit. The control structure includes a compensation strategy to guard against the performance degradation due to actuation dead times, identified by experimental tests. The eNMPC is run on an automotive rapid control prototyping unit, which shows its real-time capability with comfortable margin. A validated high-fidelity vehicle simulation model is used for the assessment of the ABS on a HiL rig equipped with the braking system hardware. The eNMPC is tested in seven emergency braking scenarios, and its performance is benchmarked against a proportional-integral-derivative (PID) controller. The eNMPC results show: 1) the control system robustness with respect to the variations in tire-road friction condition and initial vehicle speed; and 2) consistent and significant improvement of the stopping distance and wheel slip reference tracking, with respect to the vehicle with the PID ABS.

Public international dissemination events

Participation at the 1st E-VOLVE cluster Roundtable, 18 November 2021 (Virtual)

Participation at 4th Ed. RTR2020 H2020 conference, 30 November - 1 December 2020 (Virtual)

Participation at MOVE 2020, 11-12 February 2020 (London)

(publishable executive summaries of approved documents)
D1.1: Hardware components specifications in connection with cost and industrialisation

The integration strategy of the TELL project starts from the powertrain approach. Two different solutions, respectively based on two technologies have been conceived: a 4WD powertrain featuring Si-MOSFETS thin-wafer inverters paired with two SynRMaPM motors; a 2WD powertrain adopting a GaN switching FETS inverter coupled with a DMG motor. The selected DC link are 48 V and 100 V nominal to find the best possible compromise among: complexity, reduced series in the battery, reduced number of electronic components by the elimination of the DC-DC converter; weight as a compromise of the elimination of the DC-DC converter and the increased weight of the motor; cost and efficiency, thanks to the use of low cost and efficient MOSFET technology. The layout of the battery pack is conceived to assure the maximum level of fail-safe operation and reduced length of the high power cables. The integration of motor and gearbox considers several typologies of motors.

D1.2: Control software specifications

This deliverable covers the control software specifications for the two electric vehicles (EVs) platforms to be developed within the TELL project. The two platforms to be developed are: i) a four-wheel drive (4WD) electric drivetrain system equipped with 100 V Si-MOSFET inverters and Synchronous Reluctance Motors assisted by Permanent Magnets (SynRMaPM) provided by GSME; ii) a two-wheel drive (2WD) electric drivetrain system equipped with a 48 V GaN inverter and a Synchronous Reluctance Motor with Commutated Windings (SynRMCW) provided by VEEM. With respect to the 2WD and 4WD drivetrains, the technical software specifications for the component integration and communication are defined by taking the whole vehicle architecture into account. The specifications for the controllers at the component (i.e. the inverters’ software) and vehicle level are presented herein. Furthermore, the overall control architecture of the TELL project, addressing both energy-efficient control allocation and drivability enhancements, is described. The aim is to accomplish a straightforward in-vehicle integration and implementation for a smooth interaction among the controllers. The control structure involves controllers for vehicle longitudinal dynamics such as: anti-jerk; wheel slip control (for traction); front-to-total torque distribution; regenerative braking. For each of the controllers listed above, the functionality, the list of inputs/outputs to be used and the procedure for control performance evaluation are provided in detail. A set of performance indicators is identified and explained. These aim at the objective quantification of the controller behaviour along the selected manoeuvres.

D1.3: Performance indicators

The present document overviews the various Key Performance Indicators for each feature of the hardware and software subsystems. Performances of specific components needs to be properly evaluated. This holds particularly for the angular sensors which will be employed in the development of the two powertrain systems of the project. These aspects are described in section 3. Such components are crucial for proper operation of the motor drivers of both systems. First the 2WD powertrain, operated at 48 V, is analysed in section 4.1 to provide performance indicators. The focus is put on proper operations of the inverter unit and the motor features. Then in section 4.2, focus is moved to the 4WD propulsion system powered at 100 V. Suitable figures of merit are analysed to assess the performance indicators of each subsystem, from the Si MOSFET inverter and the SynRMPM motor, up to the transmission stage and wheels. Section 5.1 regards the identification of good figures of merit to probe the performance of the prototype vehicle on the road in representative urban drive cycles. Performance indicators in real world operating conditions have been defined on the basis of D1.1. KPIs have been chosen in relation with the desired performance specifications to allow advancements with respect to the state of the art. Finally, in Section 5.2, the identification of the performance indicators for the controllers that will be integrated into the two vehicle demonstrators is given. Based on D1.2, where performance indicators have already been analysed, a deeper insight is provided, discussing the reasons and importance of those quantities for the evaluation of the controllers’ behaviour.

D1.4: Requirement of simulation models

This document describes the vehicle model specifically developed for the TELL project. The model herein described aims at the virtual assessment of performance and integration of the components and the control systems for the longitudinal dynamic of the vehicle prototype. Such simulation platform will be validated against in-vehicle tests carried out on the passive vehicle so that it can be used as a solid baseline for the controllers integration. The document is organised as follows: Chapter 2 describes the Matlab scripts needed for the simulation, providing a general overview of the virtual simulation environment. Chapter 3 provides the details of the main Simulink blocks involved in the simulation, such as the driver model, the chassis model, the wheels dynamics (together with the tyre characteristics) and the powertrain/drivetrains. Chapter 4 shows the simulation examples by means of the predefined set of manoeuvres which can be customised by the user. Finally, the conclusion is reported in Chapter 5.

D2.2: Design and prototype of electronics control unit and its control law

This document is an intermediate report gathering developments made for the control of the DMG (Direct gear Motor Generator) electrical machine. It describes the constitution of the electronic parts (the inverter) as well as the control law embedded for controlling the machine in its environment. It includes the internal protection and external communication with the demonstrator vehicle. A dedicated chapter of this document presents the work initiated on the GaN (Gallium Nitride) technology as part of the commutation cell development aside of the inverter development itself

D3.1: Definition of motor and mechanical transmission requirements

The present document reports simulations and data comparisons of the behaviour of SyRMPM motor and the related transmission system over a selection of driving cycles best representing urban mobility. The results will be used to define the operating conditions of the motor provided by GSME and implemented in the first project demonstrator vehicle. This work will be the basis of the optimisation activities of D3.2, aiming at minimising power losses while keeping high torque, power and energy-consumption performances of the motor. Together with the study of the motor itself, the study includes the transmission system, from the motor to the wheels of the vehicle. Starting from the characteristics of the motor the best range of transmission ratios has been identified. The possibility to select different transmission ratios leaves a degree of freedom to the design of the whole system which has to take into account other factors as well, like geometric, mechanical, and cost constraints. The first step was taken to fulfil the performance requirements, such as maximum speed, slope, acceleration, load etc.; then the energy consumption has been evaluated as a function of the transmission ratio, to provide optimisation guidelines, when considering real operations of the vehicle.

D3.2: SynRMaPM Motor: Design, Simulation, Fabrication

The main objective for GSME/DANA, within the TELL project, is to develop an innovative 100V battery powertrain solution for urban electric vehicles based on a Synchronous Reluctance Motor Assisted by Permanent Magnets (SynRMaPM) and a Si-MOSFETs based inverter. In this document the motor development will be dealt regarding its design, simulation and fabrication. In the deliverable 3.1 motor and mechanical transmission requirements were defined and this is the starting point of the motor development. The motor engineering process interests two main aspects: electrical and mechanical design. Electrical design workflow starts from the initial electric machine design sizing to detailed electromagnetics, thermal and mechanical analyses and simulations of the machine. For this purpose, it’s been used Ansys Maxwell tool for 2D Finite Element Analysis (FEA) electromagnetics simulation. Mechanical design workflow starts from the analysis of the motor and gearbox coupling, operating limits (speed and torque), size constraints to drawings developed with CAD/CAE design tools. For this purpose, it’s been used GStarCAD and NX SolidEdge. This motor has been designed with the aim to meet the application requirements but also to reduce the BoM and manufacturing costs (designed for manufacturing). In comparison to the early initial motor prototype, the following aspects have been improved: reduced the use of magnets, simplified the rotor magnets insertion and fastening, reduced the cogging and ripple torques, lowered the voltage harmonics content generated by the motor back-EMF. Thanks to a proprietary patent already owned by GSME/DANA it was possible to realize a scalable rotor solution that permits, in the same motor frame size, to fit three different power ratings. Another important aspect regards the thermal management and system cooling of the motor. With the use of SynRMaPM technology, that has not rotor losses, it’s possible to cool the machine with natural air, avoiding any additional fans, water jackets or oil spray cooling systems. Experimental and validation tests to measure torque, efficiency, power and thermal behavior, have been carried out on a first motor prototype. To improve the reliability of the motor it’s been equipped with a novel position sensor developed specifically for the TELL (details in deliverable D5.6).

D4.1: Two vehicles ready for integration

This deliverable describes the activities performed at I-FEVS to develop two safe and lightweight vehicle architectures to integrate the 4WD powertrain provided by GSME (Group SME - DANA) and the 2WD powertrain provided VEEM (Valeo). The two vehicle architectures are completed and ready to integrate:
- The 4WD powertrain based on two identical motorised axle systems consisting of a 100V Si-MOSFETs inverter, a synchro reluctance motor and a 1:9 ratio differential.
- The 2WD powertrain based on a 48V inverter, VEEM motor and a 1:9 ratio differential.
Because the GSME and the VEEM powertrain operate at two different voltages, I-FEVS has completed the development of two battery packs operating as per the current and voltage specified in D1.2 by GSME and VEEM.
The 100-4WD is planned to be air cooled while, following the request of VEEM, the architecture for the 48V-2WD has been designed to be liquid cooled. The developed chassis are composed of a mix of Advanced Steels for the design to meet side, full frontal and off axis crash tests. The I-FEVS proprietary zone partitioned Electrical and Electronic architecture has been developed to manage the installed powertrain. The embedded firmware can be updated from a remote location with the highest conceivable level of security. The EE architecture has been completed with the integration of a 9DoF inertial platform to allow the stability control of the 4WD configuration. For the same purpose a specific electronic module has been developed by I-FEVS so that the full powertrain and the electric steering could be controlled by either an on-board sensing suite or by a remote control. Essentially, the I-FEVS TELL platform has been developed so that it could be easily transformed for Autonomous Drive.
The installation of the full powertrains (battery pack, cabling, inverter-motor) has been made to assure electromagnetic compatibility and shielding against low frequency (<150Hz) magnetic fields.
All the components of the two vehicles have been made and assembled. The subframes have been parametrised in order to accept different installation requirements. Once the GSME and the VEEM powertrains will be supplied to I-FEVS their integration and test will start. For this purpose, I-FEVS has also taken specific measures so that the mechanical fixtures of the installed powertrains could withstand the usual automotive request of 200,000km severe road tests.

D5.1: GaN HEMT manufacturing

This document presents the outcomes of T5.1.1 and to be more precise, deals with the delivery of 100V GaN HEMT devices in month 18 on a bare-die base. Task 5.1.1 is based on a 100V GaN HEMT, which was developed in the ECSEL-RIA project HiPERFORM. This technology was scheduled to be used in packaged devices. Despite of space constraints in the TELL application, it was necessary to adapt the original planning.
- The power of the application was reduced to avoid excessive parallelisation (an additional demonstrator will be built based on silicon MOSFET and benchmarking will be performed)
- Bare-die delivery with two metallization schemes to reduce risk in the further integration
A special test-flow was developed to enhance the test coverage on wafer level. Nevertheless it is not possible for many tests to be performed on waferlevel. The risk of low yield on application level is therefore increased.
To sum up, IFAT provided a working demonstrator of 100V GaN HEMTs on a bare-die base to project partner VEEM in M18. To reduce the risk during assembly of the bare-die, two different contact- metallization schemes were provided.

D5.2: GaN gate optimisation

Because of the physical properties of Gallium-Nitride (GaN) the new power electronic switches based on this material enable higher operating frequencies (leading to a smaller volume) and higher efficiencies. Never the less the first GaN-HEMTs were operated with MOSFET-drivers which were available. This led to additional circuitry and the fact, that the benefits of the new GaN devices could not be fully utilised. In task 5.1.2 of the TELL project research on a new GaN driver was executed to overcome these issues. The concept has been finalised and the outcome is reported in this deliverable. The new driver will be a single-channel non-isolated gate-driver ICs planned to be paired with Infineon CoolGaN to enable high power density designs. Due to a unique fully differential input circuitry with excellent common-mode rejection, the logic driver state is exclusively controlled by the voltage difference between the two inputs, completely independent of the driver’s reference (ground) potential. This eliminates the risk for wrong triggering and thus is a significant benefit in all applications exhibiting voltage differences between driver and controller ground. In addition, within the common-mode voltage range CMR, the TELL-driver allows to address even high-side applications.

D5.3: MOSFET benchmarking

This deliverable will report on the virtual benchmarking of different MOSFET solutions (150 and 200V OptiMOS3, 150 and 200V OptiMOS5). All discussions were held between the partners IFAT and DANA. This included also two face 2 face meetings (Villach, 15th July 2019; Arzignano, early Nov. 2019). In General the power MOSFET is the most common power device in the world and its choice can be optimised regarding low gate drive power, fast switching speed, easy advanced paralleling capability, wide bandwidth, ruggedness, easy drive, simple biasing or ease of application. In particular the discussed 150V-200V MOSFETs class belongs to the widely used low-voltage (that is, less than 200 V) class of switches. It can be found in a wide range of applications, such as most power supplies, DC-to-DC converters and low-voltage motor controllers. The application defines the parameters that should be benchmarked primarily. In this case the motor drive capabilities are in focus.
Decision on focus parameters:
- Voltage class (150V vs. 200V)
- Technology generation (OptiMOS™3 vs OptiMOS™5)
- Efficiency (minimizing on-state and switching losses)
- Robustness in motor application (Ease of use, ease of assembly)
The decisions on technology generation and voltage class could be taken after a virtual benchmarking with data sheet comparison. The remaining questions were decided in the 2nd face 2 face based on two switches which were selected after the 1st selection meeting.

D5.5: Stray field immune magnetic sensing

There are more options available for stray-field robust magnetic angle measurement. One often used principle is a differential rotating field measurement using Hall sensors. This system however also has disadvantages compared to a new type of angle measurement invented by Infineon. This new system is called “integrated End-of-Shaft” (iEoS) and is integrated into the shaft end, which provides a very good shielding of external stray-fields. An additional advantage is the robustness against placement tolerances because of the large homogenous field. This large homogenous field can also be used for placement of more redundant silicon dies or sensor products inside the same constructed space to enable functional safety diagnostics. In this funding project this first idea will be adapted to the two new types of electric motors and additionally the angle sensing product shall be improved by angle calculation on-chip and high-speed interface on chip to speed up the angle measurement including data communication and to place the silicon chip into a small package to decrease the product-diameter and to enable smaller shaft diameters. The chip development has been started in parallel and it can cause a too long development time, so that existing sensor product have to be installed for the first demonstrators. However the status of chip-development will be reported in following reports.

D5.6: Stray field robust magnetic sensor for SynRMaPM

The implementation of the proposed integrated end of shaft system using a cylindrical hollow magnet was not possible for the application due to mechanical optimization constraints. Instead DANA decided to go for a regular magnetic end of shaft angle measurement system using a diametral magnetized disc magnet. Stray field robustness is achieved by strong target magnetic fields, which reduce the effect of external stray fields to the measurement signal itself. Additionally some magnetic shielding was implemented to reduce the effect of stray fields to sufficient small levels. Fulfilment of functional safety is achieved by the usage of dual-die sensor products getting two different redundant angle signal values for the inverter signal processing.

D5.7: Stray field robust magnetic sensor for Induction Machine

The implementation of the proposed integrated end of shaft system using a cylindrical hollow magnet was performed according to Infineon guideline and proposals. An own setup adapted to the local needs was developed and a prototype including a diverse redundant magneto-resistive angle sensor on a flexible PCB was set up. This angle measurement setup for detecting the rotational position of the intended induction motor was evaluated on an angle measurement test-bench where displacements in X and Z direction could be applied. Measurement results show excellent performance of one magneto-resistive angle sensor of the dual-die product after individual offset and amplitude calibration. A reimaging problem has been the angle noise, which shall be reduced by a reduced signal bandwidth by a filter and also optimize the connection between the sensor-chip and the central control unit by short connection lines or even shielding.

D6.1: Project Guidelines

This document is a report explaining the constitution of a set of project management rules, explanations of management processes, quality checks and risk assessment. We show how quality aspects are taken into account through a number of processes and activities within TELL aligned along the three basic concepts of planning, assurance and control:

- Planning: A sound quality planning for meetings, deliverables, milestones and publications with a clear definition of responsibilities and templates are to be used to create a visual project identity. This includes also a project logo and a project website.
- Assurance: an interim reporting structure will be established together with clearly guided telephone conferences to assure that that all means are taken to provide early warning in case of upcoming issues.
- Control: Feedback is foreseen through internal processes (monthly WP and Demo Leader telephone conferences) to monitor project outcomes and implement a pro-active risk management.
Responsibilities for quality planning, assurance and control are shared between all partners, there is no single responsibility at one partner/role to keep up overall quality for TELL.

D6.2: Data management plan

The document contains the first version of Data Management Plan (DMP) for the Horizon 2020 project TELL. The different aspects detailed in the document cover the whole life cycle of the research data that will be generated within the project. A paramount aspect of the DMP is to assure that the research data are as much as possible FAIR, i.e. findable, accessible, interoperable and re-usable, both within the project consortium and for the public users. The document is structured in a question/answer fashion and it follows the guidelines on data management for the Horizon 2020 framework. The main aspects covered in the DMP include: reasons to generate research data and to make them available in open-access, beneficiaries, data formats and standards for metadata, repositories and licenses, re-use, preservation, data transfer, security aspects and data management related costs. The DMP is meant to be kept as a living document. It will be revised and updated in different phases of the project, also based on the feedback from the TELL participants during the pilot testing of the interoperability of the produced research data using the selected repositories. This will be done before the data are finally made available to the public users, at the end of the project. An updated DMP will be created by M32 and detailed in the deliverable document D6.3.

D6.4: Dissemination strategy

This deliverable reports about the dissemination strategy that is adopted in the TELL project. The objectives and message to be conveyed are first identified together with a variegated target audience that covers the whole value chain for the components, control strategies and vehicles that will be developed/enhanced within TELL. The measures for dissemination and communication are presented on two levels: i) project level, including operations like the website, social media and logo; ii) individual level, in terms of measures that each project partner will adopt within their institution to communicate the updates and advances achieved during the project and attract the relevant stakeholders. The different phases of the project dissemination activity are presented with their relative objectives and specific dissemination measures. Clustering and community building activities with other European projects are enlisted and will be pursued during the project. The impact of the planned dissemination activities will be measured by means of clear performance indicators, which are indicated in the document. Finally, some practical guidance concerning the format of disclaimers and use of the EU logo in the publications are reported.

D6.5: Exploitation strategy and planning including IP

The deliverable gives specific explanation on the exploitation strategy and IP planning of each participant within TELL project, based on their individual exploitation strategy and IP landscaping in combination with market analysis, market niches and any further innovation in electric vehicle area. The bullet points are given in each chapter corresponding to each partner, viz. exploitation plan, market overview, IP awareness and IP valorisation, IP landscaping and IP strategies, possible market niches and other relevant information such as possible technology extension and revenue sources identification. The exploitation strategy and planning including IP is set up to ensure protection and promotion of ideas developed in the project, uptake and portability of project results on the market and/or beyond the planned application. It will act as a guideline for each partner to carry out activities in deliverable 6.6, in which the effective exploitation of project results will be measured.