Luis Le Moyne

Simple method of estimating consumption of internal combustion engine for hybrid application

This article presents two simple methods to evaluate the fuel consumption of internal combustion engines. Furthermore, it points out the link between piston volume, engine size and fuel consumption as it gives the possibility to visualize the chosen working points inside an internal combustion engine operation points map. This leads to the fact that this approach is a very helpful tool for the design of hybrid systems including internal combustion engines. The two presented methods, one very simple, one more elaborated, are interesting as first approach of internal combustion engine sizing and to evaluate the consumption of internal combustion engine. The results for six pure internal combustion engines on two different driving cycles have been compared to literature data showing extremely satisfying accuracy. An application on a series hybrid vehicle underlines the potential of fuel savings due to hybrid architecture.

Characterisation of a commercial automotive lithium ion battery using extended Kalman filter

This paper presents a extented Kalman filter based on a dynamic model of a commercial lithium ion battery pack in automotive applications, and experimental data are collected using the Noao. This vehicle is an electric track with range extender, which has been developed and produced by the association Pôle de Performance de Nevers Magny-Cours (PPNMC). This model has been developed with MATLAB/Simulink to investigate the output characteristics of lithium-ion batteries. It incorporates I-V performance of the battery, battery capacity fading, temperature effect on battery performance, and the battery temperature rise. This estimation technique is used in order to estimate some parameters, which cannot be measured directly by physical sensors such as SOC and SOH and to compensate for uncertainties in the model parameters and the measurements. The proposed model is validated by comparing simulation results with experimental data collected through battery testbed of Noao vehicle.

An energy and power based approach toward design of power split for urban hybrid vehicle

This work presents a novel method of analyzing real and artificial urban driving cycles with regard to power and energy needs. The results can be used to facilitate the design of the power split between primary and secondary power sources for hybrid vehicles in urban applications. Based on the analysis of different real and artificial driving cycles three key values are defined that allow predefining the size of the primary and secondary power source.

Dynamic Modeling and Driving Cycle Prediction for a Racing Series Hybrid Car

This paper presents Noao, a plug-in series hybrid racing car equipped with an engine/generator set as range extender. To determine the velocity profile, i.e., performance of the car and its power profile, a dynamic model for this car is developed using pedal position as input. This value is easy to measure, representative for race cycles, and presents a novelty. The model is validated with the results from experiments. An analysis based on the map of Magny-Cours racing circuit and drivers pedal action on certain zones of the circuit is formulated and is used as a prediction tool to determine drivers inputs on other racing circuits and generate driving schedules. The results obtained from this analysis are essential to predict energy consumption of the system, estimate driving range, and inspect battery state-of-charge evolution of the car during races. Moreover, the generated driving cycle provides an optimum compromise between drivetime and energy consumption of the system.

Sizing of ICE and Lithium-ion battery for series hybrid vehicle over life cycle with battery aging

This paper presents a method to evaluate the volume and weight of the internal combustion engine (ICE) and lithium-ion battery for a series hybrid vehicle that allows to minimize the mean consumption over system life. Individual driving cycles of the car over a total distance of 100 000 km are simulated. The ICE and battery dimensions are approximated; the fuel consumption is evaluated using a general approach. Lithium-ion battery is described including capacity fading and the energy split between ICE and battery system is evaluated using an heuristic approach. Results show a decrease of mean fuel consumption down to 5.1 L/100km.

Artificial driving cycles for the evaluation of energetic needs of electric vehicles

This article presents a novel method to simulate artificial driving cycles that have the same significant characteristics as measured driving cycles. The driving cycles are based on only two different easily accessible parameters namely mean velocity and mean positive acceleration as well as their standard variations. Those parameters allow to adapt the driving cycles to different cycle types (urban, extra urban, highway), length and duration. Other than know drive cycle simulators, the approach is based on normal distribution of velocities and accelerations, thus needing to analyze only few cycles for the initialization.

Novel Classification of Control Strategies for Hybrid Electric Vehicles

Hybrid Electric Vehicles (HEV) only show their fuel consumption potential if the energy control provides high system efficiency. Until now control strategies were classified rule based or optimization based. For implementation it is much more interesting if they can be used in real time and if their result is close to optimum solution. Thirteen different control approaches for energy management which have already been applied in HEVs are studied based on an extensive literature review. They include rule based deterministic and Fuzzy Logic based approaches, as well as transient optimization based approaches such as Equivalent Consumption Minimization Strategy (ECMS) and global optimization based approaches like dynamic programming, game theory or genetic algorithm. Finally a novel classification with regard to needs of application is provided.

Experimental Study of Lithium-Ion Battery Thermal Behaviour for Electric and Hybrid Electric Vehicles

An experimental study of lithium-ion battery thermal behaviour for automotive applications is presented. Experiments are conducted for a pack of three battery cells which encounter a series of different discharge and cooling conditions. Results show the different temperature distribution on different locations of the battery cell surface with the highest temperature increase near the positive and negative electrode. The temperature increases sharply if the state of charge (SOC) is too small (less then 20%). Higher discharge rate contributes to higher temperature increase and bigger maximum and minimum temperature difference. Higher cooling air velocity helps to decrease the overall temperature and create better cell surface temperature distribution. Battery utilisation under real vehicle driving conditions is simulated using NEDC and Artemis rural driving cycle with different cooling strategies. Various information collected throughout this project are important in understanding the battery thermal behaviour and help in the design of better cooling systems and strategies for a better used of lithium-ion batteries in automotive applications.

Vaporization Characteristics of Ethanol Droplets: Influence of the Environment Humidity

The study of the gasification of a droplet via vaporization, which involves heat, mass and momentum transfer processes in gas and liquid phases, and their coupling at the droplet interface, is necessary for better understanding and modeling of complex spray and mixture formation issues. A detailed description of the vaporization of an isolated droplet has been realized in this experimental study aimed at investigating the impact of the water vapor contained in the surrounding gas on the evaporation of an ethanol droplet. The experimental set-up consists of a heated chamber with a cross quartz fibers configuration as droplet support. An ethanol droplet is located at the intersection of the cross with a controlled initial diameter (300–550μm). Ambient temperature is varied from 350 to 850 K. The real impact of the water concentration on the vaporization rate of an ethanol droplet in a large range of temperature is examined, showing that the vaporization of an ethanol droplet is accompanied by the simultaneous condensation of water vapour on the droplet surface and thus the temporal evolution of the droplet squared diameter exhibits an unsteady behaviour. The histories of the instantaneous vaporisation rates calculated from the d2 (t) curves confirms this non-stationary aspect of the phenomenon.Copyright