Powertrain Systems for Net-Zero Transport

The transport sector continues to shift towards alternative powertrains, particularly with the UK Government’s announcement to end the sale of petrol and diesel passenger cars by 2030 and increasing support for alternatives. Despite this announcement, the internal combustion continues to play a significant role both in the passenger car market through the use of hybrids and sustainable low carbon fuels, as well as a key role in other sectors such as heavy-duty vehicles and off-highway applications across the globe. Building on the industry-leading IC Engines conference, the 2021 Powertrain Systems for Net-Zero Transport conference (7-8 December 2021, London, UK) focussed on the internal combustion engine’s role in Net-Zero transport as well as covered developments in the wide range of propulsion systems available (electric, fuel cell, sustainable fuels etc) and their associated powertrains. To achieve the net-zero transport across the globe, the life-cycle analysis of future powertrain and energy was also discussed. Powertrain Systems for Net-Zero Transport provided a forum for engine, fuels, e-machine, fuel cell and powertrain experts to look closely at developments in powertrain technology required, to meet the demands of the net-zero future and global competition in all sectors of the road transportation, off-highway and stationary power industries

Design and Testing of a Permanent Magnet Synchronous Motor Drive System with a Novel Power Electronics Converter

Several technologies have been applied to electric vehicles (EVs) to achieve high performance in terms of mileage, speed, and efficiency. However, technological advances and customer demand are constantly revolutionizing the transportation sector. From the conventional internal combustion engine (ICE) vehicles, transportation has reached the area of hybrid electric vehicles (HEVs) and has moved towards fuel cell electric vehicles (FCEVs). Throughout this revolution, electric machines (EMs) made considerable progress. While the ICEs are phasing out because of their efficiency limitations and negative environmental impact, the EMs will remain the fundamental component of EVs. Hybrid topologies have been adopted and optimized by the industry to address several challenges related to efficiency, mileage, and ecology. However, the green transportation trend will undoubtedly lead to dominance of battery and fuel cell electric vehicles. Efficient high-speed EMs and their associated power electronics and control are therefore needed to replace and transcend ICEs. The requirement of high-speed EMs that can replace and surpass the ICE in terms of efficiency versus speed range requires associated power electronic converters that can drive the EMs through their operating envelopes. The new generation of EVs will be more demanding in terms of power, integration to the grid, efficiency, mileage; ruggedness and size reduction of power electronics interfaces and machines. The aim is to reduce the overall cost/weight of EVs and optimize energy efficiency across the entire drivetrain. This research proposes and validates a new step-by-step design method for EV drivetrain design and testing. The proposed method is based on analytically obtaining feasible drivetrain parameters from the torque-speed curve and battery nominal voltage specifications. A case study based on a 2010 Toyota Prius motor is used to validate the proposed approach for its ability to estimate feasible parameters that can be matched using finite element analysis (FEA) software. The proposed method's ability to estimate IPMSM parameters from a given SPMSM is validated iv experimentally. This method allows machines and drive specialists to work in parallel on the drivetrain component design and speed up the whole drivetrain design process. A novel integrated multipurpose power electronics interface (IMPEI) designed for PHEVs and EVs is proposed to provide a solution to the increasing need for integration and grid support of EVs. The IMPEI is analyzed, designed, prototyped, tested, and compared with several other integrated power electronics interfaces (IPEIs) and with conventional power electronics interfaces (CPEI) in this work. The proposed IMPEI and different other topologies are compared in terms of configuration, device count, cost, and efficiency, using the BMW i3 as the benchmark application. The design requirements of the IMPEI are presented and discussed, including modes of operation, switch and passive element sizing, and ratings. The results of experiments in propulsion, regenerative braking, and single-phase and three-phase V2G and G2V are presented. The experimental efficiency analysis and comparison are carried out in the propulsion, V2G, and G2V modes. The proposed analytical drivetrain design approach is used to size the drivetrain of a Renault Twizy. In this design, the IMPEI is used as a drive inverter. The potential fuel economy of the IMPEI-based Renault Twizy drivetrain is investigated based on experimental and simulation data. The IMPEI is sized and simulated in PSIM software to obtain its efficiency map throughout the operating envelope. The designed PMSM efficiency map is obtained from JMAG software. However, the mechanical system efficiency map is obtained practically throughout a drive cycle in Aachen city in Germany. A fuel economy analysis is also carried out in this work. A comparison of commonly used test benches is provided, followed by the details on the test bench used to obtain the experimental results throughout the thesis. The main components of the test bench are described. Also, a regenerative braking analysis of high-speed permanent magnet synchronous motors (PMSMs) during emergency conditions is presented. Overloading the electric machine during regenerative braking in emergency conditions using field-oriented control (FOC) is investigated

Development of automated and connected testing processes for electric vehicles

Electric vehicles provide a practical transportation solution to overcome emission and energy deficiencies posed by combustion vehicles. However, high product costs driven by the price of components and immaturity of the processes to create them reduce the product’s financial competitiveness. Manufacturers need to adapt their processes to develop cars more economically while adhering to emission requirements by legislative bodies. This EngD determined the estimated R&D cost saving made through innovating automated and connected technologies into the development process to reduce the development costs of vehicles holistically. The research targeted physical testing costs due to the potential increase in demand for testing to improve the characterisation of virtual models while the automotive industry transitions to vehicle electrification. The research established objectives to target human, capital and facility costs as significant cost drivers for physical testing. Three applications of automation and connected systems were ideated and investigated to evaluate the saving potential of each cost driver. Firstly, an automated dynamometer was designed and experimentally tested to demonstrate its capability in reducing man-hours for powertrain component testing. Secondly, a distributed test network was virtually modelled to understand the opportunities to supplement physical prototype vehicles by utilising connected component test facilities. Finally, an automated test management system with test case generation capability was proposed and evaluated to determine its capability to improve testing productivity. Using the results from each technology innovation and Jaguar Land Rover’s historical strategy, a numerical model identified an estimated saving of £225m across 12 vehicle models representing a net change of 1.71%. Changes in human resources demand were the most significant contributor toward total development cost savings. DTS and automated dynamometer innovations provided 90% and 9% of human resource cost-saving, respectively. The results suggested that these technological innovations would make only a marginal impact on saving for customers. Ultimately, a combination of further developing of these technologies to maximise application and saving made on other portions of the vehicle development process is necessary to bridge the gap between combustion and electric vehicle. However, the savings proposed would benefit manufacturers financially and allow them to also gain additional revenue by providing opportunities to release vehicle models marginally earlier

Multiphysics Simulation and Model-based System Testing of Automotive E-Powertrains

Programa Oficial de Doutoramento en Enxeñaría Naval e Industrial . 5015V01[Abstract] Model-Based System Testing emerges as a new paradigm for the development cycle that is currently gaining momentum, especially in the automotive industry. This novel approach is focused on combining computer simulation and real experimentation to shift the bulk of problem detection and redesign tasks towards the early stages of the developments. Along these lines, Model-Based System Testing is aimed at decreasing the amount of resources invested in these tasks and enabling the early identification of design flaws and operation problems before a full-vehicle prototype is available. The use of Model-Based System Testing, however, requires to implement some critical technologies, three of which will be discussed in this thesis. The first task addressed in this thesis is the design of a multiplatform framework to assess the description and resolution of the equations of motion of virtual models used in simulation. This framework enables the efficiency evaluation of different modelling and solution methods and implementations. In Model-Based System Testing contexts virtual models interact with physical components, therefore it is mandatory to guarantee their real-time capabilities, regardless of the software or hardware implementations. Second, estimation techniques based on Kalman Filters are of interest in Model- Based System Testing applications to evaluate parameters, inputs or states of a virtual model of a given system. These procedures can be combined with the use of Digital Twins, virtual counterparts of real systems, with which they exchange information in a two-way communication. The available measurements from the sensors located at a physical system can be fused with the results obtained from the simulation of the virtual model. Thus, this avenue improves the knowledge of the magnitudes that cannot be measured directly by these sensors. In turn, the outcomes obtained from the simulation of the virtual model could serve to make decisions and apply corrective actions onto the physical system. Third, co-simulation techniques are necessary when a system is split into several subsystems that are coordinated through the exchange of a reduced set of variables at discrete points in time. This is the case with a majority of Model-Based System Testing applications, in which physical and virtual components are coupled through a discrete-time communication gateway. The resulting cyber-physical applications are essentially an example of real-time co-simulation, in which all the subsystems need to achieve real-time performance. Due to the presence of physical components, which cannot iterate over their integration steps, explicit schemes are often mandatory. These, however, introduce errors associated with the inherent delays of a discrete communication interface. These errors can render co-simulation results inaccurate and even unstable unless they are eliminated. This thesis will address this correction by means of an energy-based procedure that considers the power exchange between subsystems. This research work concludes with an example of a cyber-physical application, in which real components are interfaced to a virtual environment, which requires the application of all the MBST technologies addressed in this thesis.[Resumen] Los ensayos de sistemas basados en modelos emergen como un nuevo paradigma de desarrollo que actualmente está ganando popularidad, especialmente en la industria automotriz. Este nuevo enfoque se centra en combinar la simulación por ordenador con la experimentación para desplazar la mayor parte de la detección de problemas y rediseños hacia las fases tempranas del desarrollo. De esta forma, los ensayos de sistemas basados en modelos se centran en disminuir la cantidad de recursos invertidos en estas tareas y habilitar la identificación temprana de errores de diseño y problemas durante la operación, incluso antes de que los prototipos del vehículo completo estén disponibles. Sin embargo, el uso de esta estrategia requiere implementar algunas tecnologías críticas, tres de las cuales serán tratadas en esta tesis. La primera tarea abordada en esta tesis es el diseño de un entorno multiplataforma para evaluar la descripción y resolución de las ecuaciones de la dinámica de los modelos virtuales usados en las simulaciones. Este marco permite una evaluación eficiente de las diferentes formas de modelar los sistemas y de los métodos de resolución e implementación. En este contexto de ensayos basados en modelos, los sistemas virtuales interactúan con los componentes de los sistemas físicos, por lo tanto es necesario garantizar sus capacidades de ejecución en tiempo real, independientemente de la plataforma de software y hardware utilizada. En segundo lugar, las técnicas de estimación basadas en filtros de Kalman son de gran interés en las aplicaciones que usan ensayos basados en modelos para evaluar los parámetros, entradas o estados de los modelos virtuales de un sistema dado. Estos procedimientos se pueden combinar con el uso de gemelos digitales, homólogos virtuales de un sistema físico, con el cual mantienen un flujo bidireccional de intercambio de información. Las medidas disponibles procedentes de los sensores instalados en un sistema físico se pueden combinar con los resultados obtenidos de la simulación del sistema virtual. De este modo, este enfoque mejora el conocimiento de las magnitudes que no pueden ser medidas directamente por los sensores. A su vez, los resultados de la simulación de los sistemas de los modelos virtuales pueden servir para tomar decisiones y aplicar medidas correctivas al sistema real. En tercer lugar, las técnicas de co-simulación son necesarias cuando un sistema se divide en varios subsistemas, coordinados a través del intercambio de un reducido número de variables en momentos puntuales. Este es el caso de la mayor parte de las aplicaciones que siguen la estrategia de ensayos basados en modelos, en los cuales los componentes físicos y virtuales se acoplan mediante una comunicación en tiempo discreto. Como resultado las aplicaciones ciberfísicas son en esencia un ejemplo de co-simulación en tiempo real, en la que todos los subsistemas necesitan cumplir los requisitos de ejecución en tiempo real. Debido a la presencia de componentes físicos, que no pueden reiterar sus pasos de integración, el uso de esquemas explícitos es frecuentemente necesario. Sin embargo, estos esquemas introducen errores asociados con los retrasos propios de una interfaz de tiempo discreto. Estos errores pueden dar lugar a resultados erróneos e incluso inestabilizar la co-simulación, si no son eliminados. Esta tesis aborda la corrección de la co-simulación a través de métodos energéticos basados en la potencia intercambiada por los subsistemas. Este trabajo de investigación concluye con un ejemplo de aplicación ciberfísica, en la que se conectan componentes reales a una simulación por ordenador. Esta aplicación requiere la aplicación de las tecnologías de ensayos basados en modelos presentadas a lo largo de esta tesis.[Resumo] Os ensaios de sistemas baseados en modelos xorden como un novo paradigma de desenvolvemento que actualmente está gañando popularidade, especialmente na industria automotriz. Este novo enfoque céntrase en combinar a simulación por ordenador coa experimentación para desprazar a maior parte da detección de problemas e redeseños cara as fases iniciais do ciclo de produto. Deste xeito, os ensaios de sistemas baseados en modelos fundaméntanse en diminuír a cantidade de recursos investidos nestas tarefas e habilitar a identificación temperá de erros de deseño e problemas durante a operación, aínda se os prototipos do vehículo completo non están dispoñibeis. Porén, o uso desta estratexia require implementar algunhas tecnoloxías críicas, tres das cales serán tratadas nesta tese. A primeira tarefa tratada nesta tese é o deseño dun entorno multiplataforma para avaliar a descripción e resolución das ecuacións da dinámica dos modelos virtuais empregados nas simulacións. Este entorno permite unha avaluación eficiente dos diferentes xeitos de modelar os sistemas e dos métodos de resolución e implementación. Neste contexto de ensaios baseados en modelos, os sistemas virtuais interactúan cos compoñentes dos sistemas físicos, polo tanto é necesario garantir as súas capacidades de execución en tempo real, independentemente da plataforma de hardware e software escollida. En segundo lugar, as técnicas de estimación baseadas en filtros de Kalman son de grande interese nas aplicacións que usan ensaios baseados en modelos para avaliar os seus parámetros, entradas ou estados dos modelos virtuais dun certo sistema. Estes procedementos pódense combinar co uso de xemelgos dixitais, homólogos virtuais dun sistema físico, co cal manteñen un fluxo bidireccional de intercambio de información. As medidas dispoñíbeis procedentes dos sensores instalados nun sistema físico pódense combinar cos resultados obtidos da simulación do sistema virtual. Deste xeito, este enfoque mellora o coñecemento das magnitudes que non poden ser medidas directamente polos sensores. Á súa vez, os resultados da simulación dos sistemas dos modelos virtuais poden servir para tomar decisións e aplicar medidas correctivas ao sistema real. En terceiro lugar, as técnicas de co-simulación son necesarias cando un sistema é dividido en varios subsistemas, coordinados a través do intercambio dun reducido número de variables en momentos puntuais. Este é o caso da maior parte das aplicacións que seguen a estratexia de ensaios baseados en modelos, nos cales os compoñentes físicos e virtuais se acoplan mediante unha comunicación en tempo discreto. Como resultado as aplicacións ciberfísicas son esencialmente un exemplo de co-simulación en tempo real, na que tódolos subsistemas necesitan cumprir os requisitos de execución en tempo real. Debido á presenza de compoñentes físicos, que non poden reiterar os seus pasos de integración, o uso de esquemas explícitos é polo xeral necesario. Con todo, estes esquemas introducen erros asociados cos atrasos derivados dunha interface de tempo discreto. Estes erros poden provocar resultados incorrectos e incluso inestabilizar a co-simulación, de non seren eliminados. Esta tese aborda a corrección da co-simulación a través de métodos enerxéticos baseados na potencia intercambiada polos subsistemas. Este traballo conclúe cun exemplo de aplicación ciberfísica, na que os compoñentes reais son conectados a un entorno virtual. Isto require o emprego de tódalas tecnoloxías de ensaios baseadas en modelos presentadas ao longo desta tese