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This paper investigates the impact of environmental conditions on the possible output power of photovoltaic (PV) installations on top of hybrid electric vehicles (HEVs) and battery-powered electric vehicles (BEVs). First, we discuss the characteristics and behavior of PV cells in order to provide an understanding of the energy source that we aim to integrate into vehicles. Second, we elaborate on how PV cells and panels can be simulated to estimate the potential extension of the electrical driving range (ERE) of BEVs and HEVs. In particular, we concentrate on the impact of the vehicle’s curved roof surface on the possible output of the PV installation. In this research, we present considerations for vehicles in both parking and driving conditions. More precisely, we demonstrate how the frequently changing environmental conditions that occur while driving represent significant challenges to the control of the operating voltage of PV cells. As the area for deploying PV cells on top of an electric vehicle is limited, attention needs to be paid to how to optimize and maximize the degree of efficiency of PV-powered electric vehicles.

[ES] La producción de vehículos híbridos y eléctricos (HEV & BEV) ha experimentado un crecimiento exponencial los últimos años y se sitúan como la primera opción para sustituir en un futuro a corto plazo a los vehículos diésel o gasolina gracias al gran impulso de los gobiernos estatales centrados en una transición ecológica hacia el objetivo de cero emisiones. Es por ello por lo que los problemas asociados a este tipo de tecnologías han adquirido gran importancia y las grandes compañías automovilísticas han puesto los focos en ellos para tratar de mejorar la seguridad y eficiencia de sus vehículos. Uno de los grandes problemas de la tecnología eléctrica es el fenómeno de Thermal Runaway, un fenómeno todavía bastante desconocido inherente a los elementos de almacenamiento de energía eléctrica actuales y que consiste en un aumento de la temperatura del elemento provocado por reacciones exotérmicas que se generan en él, causadas precisamente por la elevada temperatura, entrando en una retroalimentación térmica que finaliza cuando se consumen todos los materiales reactivos. Este proceso puede originar, en el peor de los casos, la combustión del módulo de baterías afectado y en consecuencia poner en peligro a los usuarios de estos vehículos. En este trabajo, por tanto, se comienza el estudio tanto numérico como experimental del proceso de Thermal Runaway en baterías de litio 18650 orientadas a vehículos híbridos y eléctricos con el fin de llegar a comprender este fenómeno profundamente y poder mejorar la seguridad de los módulos de baterías utilizados como unidad de potencia. El estudio numérico se realiza mediante dinámica de fluidos computacional (CFD) con el software Converge CFD y se centra en dos tipos de simulaciones: simulaciones termofluidodinámicas, que toman en cuenta los campos de temperaturas en el dominio incluso considerando posibles procesos de combustión; y simulaciones fluidodinámicas donde la modelización se centra en los procesos físicos de producción, [EN] Hybrid and electric vehicles (HEV & BEV) production have experienced an exponential growth last couple of years and are the most popular option for replacing diesel and gasoline vehicles in short term thanks to the great push the governments, focused on a green transition to the zero emissions objective, are giving to them. Due to this, big automotive companies are putting their efforts in solving the most common problems related to this technology to improve the safety and efficiency of their vehicles. One of the biggest problems of the electric technology is the Thermal Runaway phenomena, a still quite misunderstood phenomena inherent to current electric batteries which consists in a temperature increase caused by exothermic reactions generated inside them, originated by this high temperature and starting so an uncontrolled thermal positive feedback that ends when all the reagents are consumed. This process can trigger, at worst, the combustion of the damaged battery module, compromising the safety of these vehicles¿ users. Therefore, this Master thesis consists in establishing the bases of a both numerical and experimental study of the Thermal Runaway process in lithium-ion 18650 batteries used in hybrid and electric vehicles with the purpose of comprehend deeply this phenomenon and be able to improve the security of their battery modules. In one hand, the numerical study is done by computational fluid dynamics (CFD) with the software Converge CFD and is focused on two types of simulations: Thermal fluid dynamic simulations, which consider temperature fields in the computational domain and including modelling of possible combustion processes; and fluid dynamic simulations which are focused in the modelling of the physical processes of production and ejection of gases in a damaged and isolated lithium battery. In the results of these simulations are analysed the temperatures reached in a battery module with a battery cell in Thermal Runaway, the mix of the ej

[ES] La producción de vehículos híbridos y eléctricos (HEV & BEV) ha experimentado un crecimiento exponencial los últimos años y se sitúan como la primera opción para sustituir en un futuro a corto plazo a los vehículos diésel o gasolina gracias al gran impulso de los gobiernos estatales centrados en una transición ecológica hacia el objetivo de cero emisiones. Es por ello por lo que los problemas asociados a este tipo de tecnologías han adquirido gran importancia y las grandes compañías automovilísticas han puesto los focos en ellos para tratar de mejorar la seguridad y eficiencia de sus vehículos. Uno de los grandes problemas de la tecnología eléctrica es el fenómeno de Thermal Runaway, un fenómeno todavía bastante desconocido inherente a los elementos de almacenamiento de energía eléctrica actuales y que consiste en un aumento de la temperatura del elemento provocado por reacciones exotérmicas que se generan en él, causadas precisamente por la elevada temperatura, entrando en una retroalimentación térmica que finaliza cuando se consumen todos los materiales reactivos. Este proceso puede originar, en el peor de los casos, la combustión del módulo de baterías afectado y en consecuencia poner en peligro a los usuarios de estos vehículos. En este trabajo, por tanto, se comienza el estudio tanto numérico como experimental del proceso de Thermal Runaway en baterías de litio 18650 orientadas a vehículos híbridos y eléctricos con el fin de llegar a comprender este fenómeno profundamente y poder mejorar la seguridad de los módulos de baterías utilizados como unidad de potencia. El estudio numérico se realiza mediante dinámica de fluidos computacional (CFD) con el software Converge CFD y se centra en dos tipos de simulaciones: simulaciones termofluidodinámicas, que toman en cuenta los campos de temperaturas en el dominio incluso considerando posibles procesos de combustión; y simulaciones fluidodinámicas donde la modelización se centra en los procesos físicos de producción, [EN] Hybrid and electric vehicles (HEV & BEV) production have experienced an exponential growth last couple of years and are the most popular option for replacing diesel and gasoline vehicles in short term thanks to the great push the governments, focused on a green transition to the zero emissions objective, are giving to them. Due to this, big automotive companies are putting their efforts in solving the most common problems related to this technology to improve the safety and efficiency of their vehicles. One of the biggest problems of the electric technology is the Thermal Runaway phenomena, a still quite misunderstood phenomena inherent to current electric batteries which consists in a temperature increase caused by exothermic reactions generated inside them, originated by this high temperature and starting so an uncontrolled thermal positive feedback that ends when all the reagents are consumed. This process can trigger, at worst, the combustion of the damaged battery module, compromising the safety of these vehicles¿ users. Therefore, this Master thesis consists in establishing the bases of a both numerical and experimental study of the Thermal Runaway process in lithium-ion 18650 batteries used in hybrid and electric vehicles with the purpose of comprehend deeply this phenomenon and be able to improve the security of their battery modules. In one hand, the numerical study is done by computational fluid dynamics (CFD) with the software Converge CFD and is focused on two types of simulations: Thermal fluid dynamic simulations, which consider temperature fields in the computational domain and including modelling of possible combustion processes; and fluid dynamic simulations which are focused in the modelling of the physical processes of production and ejection of gases in a damaged and isolated lithium battery. In the results of these simulations are analysed the temperatures reached in a battery module with a battery cell in Thermal Runaway, the mix of the ej

[ES] La producción de vehículos híbridos y eléctricos (HEV & BEV) ha experimentado un crecimiento exponencial los últimos años y se sitúan como la primera opción para sustituir en un futuro a corto plazo a los vehículos diésel o gasolina gracias al gran impulso de los gobiernos estatales centrados en una transición ecológica hacia el objetivo de cero emisiones. Es por ello por lo que los problemas asociados a este tipo de tecnologías han adquirido gran importancia y las grandes compañías automovilísticas han puesto los focos en ellos para tratar de mejorar la seguridad y eficiencia de sus vehículos. Uno de los grandes problemas de la tecnología eléctrica es el fenómeno de Thermal Runaway, un fenómeno todavía bastante desconocido inherente a los elementos de almacenamiento de energía eléctrica actuales y que consiste en un aumento de la temperatura del elemento provocado por reacciones exotérmicas que se generan en él, causadas precisamente por la elevada temperatura, entrando en una retroalimentación térmica que finaliza cuando se consumen todos los materiales reactivos. Este proceso puede originar, en el peor de los casos, la combustión del módulo de baterías afectado y en consecuencia poner en peligro a los usuarios de estos vehículos. En este trabajo, por tanto, se comienza el estudio tanto numérico como experimental del proceso de Thermal Runaway en baterías de litio 18650 orientadas a vehículos híbridos y eléctricos con el fin de llegar a comprender este fenómeno profundamente y poder mejorar la seguridad de los módulos de baterías utilizados como unidad de potencia. El estudio numérico se realiza mediante dinámica de fluidos computacional (CFD) con el software Converge CFD y se centra en dos tipos de simulaciones: simulaciones termofluidodinámicas, que toman en cuenta los campos de temperaturas en el dominio incluso considerando posibles procesos de combustión; y simulaciones fluidodinámicas donde la modelización se centra en los procesos físicos de producción, [EN] Hybrid and electric vehicles (HEV & BEV) production have experienced an exponential growth last couple of years and are the most popular option for replacing diesel and gasoline vehicles in short term thanks to the great push the governments, focused on a green transition to the zero emissions objective, are giving to them. Due to this, big automotive companies are putting their efforts in solving the most common problems related to this technology to improve the safety and efficiency of their vehicles. One of the biggest problems of the electric technology is the Thermal Runaway phenomena, a still quite misunderstood phenomena inherent to current electric batteries which consists in a temperature increase caused by exothermic reactions generated inside them, originated by this high temperature and starting so an uncontrolled thermal positive feedback that ends when all the reagents are consumed. This process can trigger, at worst, the combustion of the damaged battery module, compromising the safety of these vehicles¿ users. Therefore, this Master thesis consists in establishing the bases of a both numerical and experimental study of the Thermal Runaway process in lithium-ion 18650 batteries used in hybrid and electric vehicles with the purpose of comprehend deeply this phenomenon and be able to improve the security of their battery modules. In one hand, the numerical study is done by computational fluid dynamics (CFD) with the software Converge CFD and is focused on two types of simulations: Thermal fluid dynamic simulations, which consider temperature fields in the computational domain and including modelling of possible combustion processes; and fluid dynamic simulations which are focused in the modelling of the physical processes of production and ejection of gases in a damaged and isolated lithium battery. In the results of these simulations are analysed the temperatures reached in a battery module with a battery cell in Thermal Runaway, the mix of the ej

The automotive industry has grown considerably over the last century consequently increasing green-house gas emissions and thus contributing towards increase in the average global temperature. It is thus of paramount importance to increase the use of alternative energy sources. Electric vehicles have gained popularity over the last decade. However, a major concern with electric vehicles is their range. The range of an electric vehicle is limited by the battery pack, in particular, the weakest cell of the pack. One method of increasing the available energy from the battery pack is by introducing more electronics. Modular multilevel converters, with their modular concept, could be a viable solution. The concept of battery-integrated modular multilevel converters (BI-MMC) for automotive applications is explored. In particular, the impact of the number of cascaded cells per submodule is investigated, considering battery losses, DC-link capacitor losses, and the converter losses. Furthermore, an optimization of the DC-link capacitors and the selection of MOSFET switching frequency is presented in order to minimize the total losses.

The automotive industry has grown considerably over the last century consequently increasing green-house gas emissions and thus contributing towards increase in the average global temperature. It is thus of paramount importance to increase the use of alternative energy sources. Electric vehicles have gained popularity over the last decade. However, a major concern with electric vehicles is their range. The range of an electric vehicle is limited by the battery pack, in particular, the weakest cell of the pack. One method of increasing the available energy from the battery pack is by introducing more electronics. Modular multilevel converters, with their modular concept, could be a viable solution. The concept of battery-integrated modular multilevel converters (BI-MMC) for automotive applications is explored. In particular, the impact of the number of cascaded cells per submodule is investigated, considering battery losses, DC-link capacitor losses, and the converter losses. Furthermore, an optimization of the DC-link capacitors and the selection of MOSFET switching frequency is presented in order to minimize the total losses.

The automotive industry has grown considerably over the last century consequently increasing green-house gas emissions and thus contributing towards increase in the average global temperature. It is thus of paramount importance to increase the use of alternative energy sources. Electric vehicles have gained popularity over the last decade. However, a major concern with electric vehicles is their range. The range of an electric vehicle is limited by the battery pack, in particular, the weakest cell of the pack. One method of increasing the available energy from the battery pack is by introducing more electronics. Modular multilevel converters, with their modular concept, could be a viable solution. The concept of battery-integrated modular multilevel converters (BI-MMC) for automotive applications is explored. In particular, the impact of the number of cascaded cells per submodule is investigated, considering battery losses, DC-link capacitor losses, and the converter losses. Furthermore, an optimization of the DC-link capacitors and the selection of MOSFET switching frequency is presented in order to minimize the total losses.

The automotive industry has grown considerably over the last century consequently increasing green-house gas emissions and thus contributing towards increase in the average global temperature. It is thus of paramount importance to increase the use of alternative energy sources. Electric vehicles have gained popularity over the last decade. However, a major concern with electric vehicles is their range. The range of an electric vehicle is limited by the battery pack, in particular, the weakest cell of the pack. One method of increasing the available energy from the battery pack is by introducing more electronics. Modular multilevel converters, with their modular concept, could be a viable solution. The concept of battery-integrated modular multilevel converters (BI-MMC) for automotive applications is explored. In particular, the impact of the number of cascaded cells per submodule is investigated, considering battery losses, DC-link capacitor losses, and the converter losses. Furthermore, an optimization of the DC-link capacitors and the selection of MOSFET switching frequency is presented in order to minimize the total losses.

The automotive industry has grown considerably over the last century consequently increasing green-house gas emissions and thus contributing towards increase in the average global temperature. It is thus of paramount importance to increase the use of alternative energy sources. Electric vehicles have gained popularity over the last decade. However, a major concern with electric vehicles is their range. The range of an electric vehicle is limited by the battery pack, in particular, the weakest cell of the pack. One method of increasing the available energy from the battery pack is by introducing more electronics. Modular multilevel converters, with their modular concept, could be a viable solution. The concept of battery-integrated modular multilevel converters (BI-MMC) for automotive applications is explored. In particular, the impact of the number of cascaded cells per submodule is investigated, considering battery losses, DC-link capacitor losses, and the converter losses. Furthermore, an optimization of the DC-link capacitors and the selection of MOSFET switching frequency is presented in order to minimize the total losses.

The electric hybridization of heavy-duty road vehicles is a promising alternative to reduce the environmental impact of freight and passengers transportation. Employing a micro gas turbine as a prime mover offers several advantages: high power density, fuel flexibility, ultra-low emissions (without the need of exhaust after-treatment), low vibrations and noise, simplicity and lower maintenance cost. State-of-the-art micro gas turbines feature an efficiency of 30%, which can be increased to 40% by employing a mini organic Rankine cycle system as a bottoming power plant. Such a combined-cycle powertrain could achieve considerably higher efficiency with next-gen micro gas turbines and mini ORC systems, especially with an R&D push of the automotive sector. This paper presents the analysis of a hybrid electric heavy-duty vehicle with a prime mover based on this concept. The assessment was performed in two steps: (i) preliminary design of the combined cycle power plant, and (ii) estimation of the vehicle fuel economy and of the emissions over a representative driving cycle. The best combined cycle system stemming from the design exercise features an estimated peak efficiency of 44%, and a nominal power output of about 150 kW. This corresponds to the power demand at cruise condition of a long-haul truck (weight approx. 36 ton). A series configuration with Lithium-Ion batteries was selected for the hybrid powertrain, for it decouples the prime mover dynamics from the power demand. The benchmark is a vehicle featuring a next generation diesel engine, with a peak efficiency equal to 50%. The results show that the fuel economy can be largely improved by increasing the size of the battery in the hybrid powertrain. Furthermore, employing natural gas in the prime mover of the hybrid vehicle leads to ultra-low emissions that are well below the limits set by European and north American regulations, without the need of exhaust gas aftertreatment. Additionally, the CO2 emissions, Flight Performance and Propulsion

The electric hybridization of heavy-duty road vehicles is a promising alternative to reduce the environmental impact of freight and passengers transportation. Employing a micro gas turbine as a prime mover offers several advantages: high power density, fuel flexibility, ultra-low emissions (without the need of exhaust after-treatment), low vibrations and noise, simplicity and lower maintenance cost. State-of-the-art micro gas turbines feature an efficiency of 30%, which can be increased to 40% by employing a mini organic Rankine cycle system as a bottoming power plant. Such a combined-cycle powertrain could achieve considerably higher efficiency with next-gen micro gas turbines and mini ORC systems, especially with an R&D push of the automotive sector. This paper presents the analysis of a hybrid electric heavy-duty vehicle with a prime mover based on this concept. The assessment was performed in two steps: (i) preliminary design of the combined cycle power plant, and (ii) estimation of the vehicle fuel economy and of the emissions over a representative driving cycle. The best combined cycle system stemming from the design exercise features an estimated peak efficiency of 44%, and a nominal power output of about 150 kW. This corresponds to the power demand at cruise condition of a long-haul truck (weight approx. 36 ton). A series configuration with Lithium-Ion batteries was selected for the hybrid powertrain, for it decouples the prime mover dynamics from the power demand. The benchmark is a vehicle featuring a next generation diesel engine, with a peak efficiency equal to 50%. The results show that the fuel economy can be largely improved by increasing the size of the battery in the hybrid powertrain. Furthermore, employing natural gas in the prime mover of the hybrid vehicle leads to ultra-low emissions that are well below the limits set by European and north American regulations, without the need of exhaust gas aftertreatment. Additionally, the CO2 emissions, Flight Performance and Propulsion

Les véhicules électriques et hybrides font partie des éléments clés pour résoudre les problèmes de réchauffement de la planète et d'épuisement des ressources en combustibles fossiles dans le domaine du transporte. En raison des limites des différents systèmes de stockage et de conversion d’énergie en termes de puissance et d'énergie, les hybridations sont intéressantes pour les véhicules électriques (VE). Dans cette thèse, deux hybridations typiques sont étudiées • un sous-système de stockage d'énergie hybride combinant des batteries et des supercondensateurs (SC) ; • et un sous-système de traction hybride parallèle combinant moteur à combustion interne et entraînement électrique. Ces sources d'énergie et ces conversions combinées doivent être gérées dans le cadre de stratégies de gestion de l'énergie (SGE). Parmi celles-ci, les méthodes basées sur l'optimisation présentent un intérêt en raison de leur approche systématique et de leurs performances élevées. Néanmoins, ces méthodes sont souvent compliquées et demandent beaucoup de temps de calcul, ce qui peut être difficile à réaliser dans des applications réelles. L'objectif de cette thèse est de développer des SGE simples mais efficaces basées sur l'optimisation en temps réel pour un VE et un camion à traction hybride parallèle alimentés par des batteries et des SC (système de stockage hybride). Les complexités du système étudié sont réduites en utilisant la représentation macroscopique énergétique (REM). La REM permet de réaliser des modèles réduits pour la gestion de l'énergie au niveau de la supervision. La théorie du contrôle optimal est ensuite appliquée à ces modèles réduits pour réaliser des SGE en temps réel. Ces stratégies sont basées sur des réductions de modèle appropriées, mais elles sont systématiques et performantes. Les performances des SGE proposées sont vérifiées en simulation par comparaison avec l’optimum théorique (programmation dynamique). De plus, les capacités en temps réel des SGE développée, Electric and hybrid vehicles are among the keys to solve the problems of global warming and exhausted fossil fuel resources in transportation sector. Due to the limits of energy sources and energy converters in terms of power and energy, hybridizations are of interest for future electrified vehicles. Two typical hybridizations are studied in this thesis: • hybrid energy storage subsystem combining batteries and supercapacitors (SCs); and • hybrid traction subsystem combining internal combustion engine and electric drive. Such combined energy sources and converters must be handled by energy management strategies (EMSs). In which, optimization-based methods are of interest due to their high performance. Nonetheless, these methods are often complicated and computation consuming which can be difficult to be realized in real-world applications. The objective of this thesis is to develop simple but effective real-time optimization-based EMSs for an electric car and a parallel hybrid truck supplied by batteries and SCs. The complexities of the studied system are tackled by using Energetic Macroscopic Representation (EMR) which helps to conduct reduced models for energy management at the supervisory level. Optimal control theory is then applied to these reduced models to accomplish real-time EMSs. These strategies are simple due to the suitable model reductions but systematic and high-performance due to the optimization-based methods. The performances of the proposed strategies are verified via simulations by comparing with off-line optimal benchmark deduced by dynamic programming. Moreover, real-time capabilities of these novel EMSs are validated via experiments by using reduced-scale power hardware-in-the-loop simulation. The results confirm the advantages of the proposed strategies developed by the unified approach in the thesis.

Vehicles with hybrid drive systems are characterized by their driving dynamics, their energy efficiency and their environment-friendliness especially. Dependent on the electrical power and the drive train structure these hybrid drives are grouped into different classes. Designations such as micro-hybrid, mild- hybrid, full-hybrid, serial-hybrid, serial/parallel-hybrid or power-split-hybrid reflect the large variance of these different drive train possibilities. In hybrid drive systems electronically controlled converters take an important role. With such a converter also the energy exchange between electrical power system and electrical machine is regulated. The reduction of the vehicle fuel consumption here is of special interest. Today's hybrid vehicles use for the control mainly information from the present driving conditions, taking into account the actual electrical power system-charge as well as the power demand of the driver. With such a control already considerable fuel reductions are reached. But additionally superimposed control and information systems promise substantial potential for more fuel reduction. With these systems an outstanding energy-saving and anticipatory way of driving could be realized. The aim is to find the best operating point in each case for the combustion engine and to adapt the charge state of the electrical power system to the respective driving situation.

Vehicles with hybrid drive systems are characterized by their driving dynamics, their energy efficiency and their environment-friendliness especially. Dependent on the electrical power and the drive train structure these hybrid drives are grouped into different classes. Designations such as micro-hybrid, mild- hybrid, full-hybrid, serial-hybrid, serial/parallel-hybrid or power-split-hybrid reflect the large variance of these different drive train possibilities. In hybrid drive systems electronically controlled converters take an important role. With such a converter also the energy exchange between electrical power system and electrical machine is regulated. The reduction of the vehicle fuel consumption here is of special interest. Today's hybrid vehicles use for the control mainly information from the present driving conditions, taking into account the actual electrical power system-charge as well as the power demand of the driver. With such a control already considerable fuel reductions are reached. But additionally superimposed control and information systems promise substantial potential for more fuel reduction. With these systems an outstanding energy-saving and anticipatory way of driving could be realized. The aim is to find the best operating point in each case for the combustion engine and to adapt the charge state of the electrical power system to the respective driving situation.

In this paper, the thermal impact of using different impregnation materials on high-performance liquid-cooled electric machines is studied. In this regard, varnish, Epoxylite, and a silicone-based thermally conductive material are considered. To study thermal effects of using different impregnation materials in theory, an advanced lumped-parameter thermal model of the studied electric machines is developed. In addition to the simulation studies, three identical induction machines using the aforementioned materials are manufactured and evaluated. Experimental tests are carried out at a wide range of current magnitudes and cooling conditions. A good agreement between the temperature measurements and corresponding simulation results is observed. It is demonstrated that using innovative thermally conductive materials in the stator slots and the end winding bodies of liquid-cooled electric machines results in a significant reduction in the winding hot spot temperature. Additionally, the influence of the critical parameters on the impregnation material performance, e. g., impregnation goodness and slot fill factor, is studied., Updated from Submitted to Published. QC 20140715

This paper presents an advanced lumped parameter (LP) thermal model for a permanent-magnet assisted synchronous reluctance machine (PMaSRM) developed for propulsion in a hybrid electric vehicle. Particular focus is put on the stator winding and a thermal model is proposed that divides the stator slot into a number of elliptical copper and impregnation layers. The model is enabled by the derivation of an approximate analytical expression for the thermal resistance of an elliptical cylinder with constant thickness. The approach is attractive due to its simplicity and the fact that it closely models the actual temperature distribution for common slot geometries. Additionally, an analysis, using results from a proposed simplified thermal finite element model representing only one slot of the stator and its corresponding end winding, is presented in which the number of layers and the proper connection between the parts of the LP thermal model representing the end winding and the active part of winding is determined. The presented thermal model is evaluated experimentally on a PMaSRM equipped with a water cooling jacket, and a good correspondence between the predicted and measured temperatures is obtained., QC 20150629

This paper considers a permanent magnet assisted synchronous reluctance (PMSynRel) machine for an integrated charger application for use in a plug-in hybrid electric vehicle (PHEV). The integrated charger functionality means that the machine is also used when the battery is charged from the electrical grid. A finite element model (FEM) is presented from which a transient model of the complete system is derived. The resulting model can be used for simulating and tuning the algorithms needed to synchronize the machine to the electrical grid and controlling the charging process., QC 20120119

The free-piston energy converter (FPEC) is used for a series hybrid electric vehicle scheme, which may have the advantages of high efficiency, compact structure, and reliable operation. The linear generator is an important part in the FPEC, and a tubular longitudinal flux permanent-magnet (PM) linear generator scheme is investigated in this paper. The electromagnetic and thermal properties of the generator are analyzed with commercial software Flux 2D. The generator is optimized from the aspects of material selection and structure optimization. Rare-earth PM material VACODYM 655HR is selected for the permanent magnets, and low-performance low-loss material M235-35A is chosen for the stator lamination. The pole number and machine size are optimized, and the optimum scheme with efficiency of 0.935 and specific power of 1.49 kW/kg is obtained, which meets the requirements of FPEC application., QC 20100525

A Free Piston Energy Converter (FPEC) is a combination of a linear combustion engine and a linear electrical machine. This type of converter has many potential advantages like high efficiency, low fuel consumption and low emissions, which make it suitable for a series hybrid vehicle. However, the generated power pulsates due to the reciprocating motion of the translator. This paper presents a comparative study on how different generator force profiles affect the electric power pulsations produced by the FPEC. In addition, the influence of these profiles on translator motion and the needed power converter current is investigated. A dynamic free piston model is used for the investigation. Results show that the generator force profile has a major impact on the power pulsation amplitude and peak current demand. Thus the chosen force profile will affect dimensioning of power converter, electrical machine and energy storage. Furthermore, loading the translator heavily in the beginning or end of the stroke seems to affect the peak translator velocity more than evenly distributed load profiles., QC 20101116

USDOT Grant 69A3551747114, National Transportation Library (NTL) Curation Note: As this dataset is preserved in a repository outside U.S. DOT control, as allowed by the U.S. DOT’s Public Access Plan (https://doi.org/10.21949/1503647) Section 7.4.2 Data, the NTL staff has performed NO additional curation actions on this dataset. The current level of dataset documentation is the responsibility of the dataset creator. NTL staff last accessed this dataset at its repository URL on 2023-07-27. If, in the future, you have trouble accessing this dataset at the host repository, please email NTLDataCurator@dot.gov describing your problem. NTL staff will do its best to assist you at that time., Past research has shown on-road emissions patterns unique to HEVs, indicating the need to account for them in emissions models. The main objective of this work is to outline a framework for development of new HEV emissions models based on current knowledge of CV emissions. The premise is that accurate knowledge of the instantaneous (1 Hz) power split between the HEV combustion and electric propulsion sources can be used to modify existing CV emission models for HEV emission predictions that are currently lacking in regulatory models. The HEV power split metric, instantaneous hybridization factor (IHF), was developed and quantified with on-road data collected from a 2010 Toyota Camry HEV operating on a fixed route in hilly Vermont over all seasons. IHF is the second-by-second ratio of electric system power to total system power and accounts for energy storage in the high voltage battery. IHF ranges from -1 to +1 and varies widely with vehicle speed and VSP. Different road types on the driving route were associated with different proportions of binned IHF activity, which represent the three key HEV operating states defined in this study: electric-drive only (EDO), power recovery and electric-drive assist. A more detailed analysis of IHF relationships to tailpipe emissions and road grade is found in a recently published article (Ref 1)., The total size of the described zip file is 65.6 MB. The .csv, Comma Separated Value, file is a simple format that is designed for a database table and supported by many applications. The .csv file is often used for moving tabular data between two different computer programs, due to its open format. Any text editor or spreadsheet program will open .csv files. PDFs are used to display text and images and can be opened with any PDF reader or editor.