Convertisseur à ponts en H cascadés pour chaîne de traction de véhicule électrique : modélisation, performances et dimensionnement

Reducing greenhouse gas (GHG) emissions is now, more than ever, an imperative. Individual vehicles are deeply rooted in our society and our urban infrastructures, making the development of alternatives to thermal cars essential. Electric vehicles (EVs) stand out for their low GHG emissions over their lifetime, despite a high initial carbon debt due to battery manufacturing. In 2024, EVs will represent 19% of sales in Europe. The challenges associated with the diffusion of these new technologies to the general public require constant improvement, particularly in autonomy and consumption. . The work presented in this thesis is part of the PIA ADEME IBIS project. The main goal of this project is the development of a new powertrain architecture for electric vehicles based on a modular multilevel converter. This thesis is particularly interested in the modeling and study of the energy performances of this new system in comparison with existing structures. Simulations of vehicle driving cycles are carried out in order to evaluate the consumption of architectures in realistic conditions. The questions of sizing and control of the structure are also addressed to seek a compromise between reduction of consumption and quality of waveforms.The presentation of electric vehicle technologies, whose powertrain is made up of a three-phase inverter connecting the electric machine to the battery, illustrates the constraints of their design. Multilevel converters then present prospects for new modular traction chain structures combining energy storage and power electronics. In this sense, the thesis focuses on a battery converter system with cascaded H-bridges, exploiting a high degree of modularity to benefit from less switching control.After having defined and justified the use of the Energetic Macroscopic Representation (EMR), the subsystems are modeled with particular attention to the traction chain: machine, semiconductors and batteries. The models are validated experimentally. The strength of the models built using EMR makes it possible to study the influence of parameters without modifying the representation, thus seeking an optimal configuration of the structure based on performance and quality criteria.The models are simulated to compare the cascaded H-bridges (CHB) converter powertrain structure with conventional topologies, including an IGBT inverter and a SiC MOSFET inverter. The quality indicators used demonstrate excellent performance at high-speed for CHB inverter. Simulations of realistic driving cycles reveal that SiC and CHB converters significantly improve consumption at low speeds, particularly advantageous for urban cycles. On the other hand, at high speed, consumption is essentially due to the forward motion of the vehicle, which reduces potential gains.Exploring the possible configurations of the cascaded structure shows that the optimal consumption configuration is around 10 cells per module, or 12 modules, with a voltage per level between 30 and 40 V. This configuration is a compromise influenced by the range of available transistors and power quality. The latter is important for recharging the vehicle. Although reducing the number of levels improves losses, it may require modulation strategies to compensate for degraded quality at low speeds.This work is intended to be pioneering in the system study of CHB modular multilevel converters for electric vehicles. A wide field of perspectives for varied disciples is offered by this structure.