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Theses
Modélisation et stabilité d'un régulateur hybride de courant - Application aux convertisseurs pour pile à combustible
Modélisation et stabilité d'un régulateur hybride de courant - Application aux convertisseurs pour pile à combustible
Abstract : This thesis discusses the control of static converter interfaces between fuel cells and associated electrical loads.
After establishing the voltage-current characteristic of the fuel cells to justify the use of static converters, an
analysis is carried out on continuous-continuous conversion structures. Details are given on the basic boost
converter structure and the paralleled operation of several such converters. This last one is a satisfied solution for
high current/low voltage supply such as the fuel cells. Two cases are then considered to realise the inductances
of these converters. Firstly, when inductances are independent of each other. Secondly when inductances are
realised in the same magnetic core.
A hybrid current regulator is then proposed for the control of continuous-continuous converters when subject to
supply voltage fluctuations and of operating voltage range typical of a PEM fuel cell. The regulator operates at
fixed frequency and includes the properties of three control modes, sliding control mode for its robustness and
the turn-off and turn-on current mode controls allowing proper operation of the system for any value of the duty
cycle. Stability of the system using averaged models in low and high frequencies is presented. As the averaged
model cannot allow the study of the exact cycle described by the trajectory of the system, a mathematical model
based on the Floquet multipliers is derived. It allows highlighting the robustness of the regulator when the
inductance and the voltage supply of the converter vary in a large range.
After establishing the voltage-current characteristic of the fuel cells to justify the use of static converters, an
analysis is carried out on continuous-continuous conversion structures. Details are given on the basic boost
converter structure and the paralleled operation of several such converters. This last one is a satisfied solution for
high current/low voltage supply such as the fuel cells. Two cases are then considered to realise the inductances
of these converters. Firstly, when inductances are independent of each other. Secondly when inductances are
realised in the same magnetic core.
A hybrid current regulator is then proposed for the control of continuous-continuous converters when subject to
supply voltage fluctuations and of operating voltage range typical of a PEM fuel cell. The regulator operates at
fixed frequency and includes the properties of three control modes, sliding control mode for its robustness and
the turn-off and turn-on current mode controls allowing proper operation of the system for any value of the duty
cycle. Stability of the system using averaged models in low and high frequencies is presented. As the averaged
model cannot allow the study of the exact cycle described by the trajectory of the system, a mathematical model
based on the Floquet multipliers is derived. It allows highlighting the robustness of the regulator when the
inductance and the voltage supply of the converter vary in a large range.
Cited literature [38 references]
https://tel.archives-ouvertes.fr/tel-00083112
Contributor : Christine Pierson <>
Submitted on : Thursday, June 29, 2006 - 3:17:51 PM
Last modification on : Thursday, January 18, 2018 - 3:06:04 PM
Long-term archiving on: : Monday, April 5, 2010 - 9:54:51 PM
Contributor : Christine Pierson <>
Submitted on : Thursday, June 29, 2006 - 3:17:51 PM
Last modification on : Thursday, January 18, 2018 - 3:06:04 PM
Long-term archiving on: : Monday, April 5, 2010 - 9:54:51 PM