Nassim Rayane BENNACER defended his PhD on April. 10th, 2026.
Place : amphitheatre 6 Marie Curie (Lyon 1), on the campus of la Doua (1 rue J. B. Lamarck, 69100 Villeurbanne)
Development of a power electronics converter 48 V/1000 V for Piezoelectric-based valve driving applications
Jury :
Rapporteurs :
Mme. CLAVEL Edith, Professeure des Universités, Université Grenoble Alpes
M. DESPESSE Ghislain, Directeur de recherche, CEA Grenoble
Examinateurs :
Mme. BAHRI Imen, Maître de Conférences, Université Paris-Saclay
M. FREY David, Maitre de Conférences, Université Grenoble Alpes
M. JOUBERT Charles, Professeur des Universités, Université Claude Bernard Lyon 1
Encadrement :
M. MARTIN Christian, Professeur des Universités, Université Claude Bernard Lyon 1, Directeur de thèse
M. PACE Loris, Maître de Conférences, École Centrale de Lyon, co-encadrant
Abstract :
Nowadays, most off-road vehicles rely on internal combustion engines coupled with hydraulic transmissions, mainly due to their high power density. In order to improve controllability while reducing noise and vibrations, the P4Hydro project proposes the integration of fast piezoelectric actuators (with a response time of approximately 1 ms) into the hydraulic system. However, driving such actuators requires power electronics capable of delivering high voltages to supply capacitive loads.
This PhD work focuses on the development of a power conversion architecture designed to supply several piezoelectric actuators at 1000 V from a 48 V battery source. The proposed architecture relies on a high step-up DC/DC converter (48 V / 1000 V), followed by DC/AC converters dedicated to the individual control of each actuator with actuation times adjusted to 1 ms. The two conversion stages (DC/DC and DC/AC) are first validated separately and then integrated in order to demonstrate the operation of the complete conversion architecture.
Keywords: Piezoelectric actuators, DC/AC piezo-driver converter, DC–DC step-up (boost) converter, high-gain DC/DC converter, hydraulic transmission, off-road vehicles.