Algebraic observer design for PEM fuel cell system

© 20xx IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.In this paper, the concept of the algebraic observer is applied to Proton Exchange Membrane Fuel Cell (PEMFC) system. The aim of the proposed observer is to reconstruct the oxygen excess ratio through estimation of their relevant states in real time from the measurement of the supply manifold air pressure. A robust differentiation method is adopted to estimate in finite-time the time derivative of the supply manifold air pressure. Then, the relevant states are reconstructed based on the output-state inversion model. The objective is to minimize the use of extra sensors in order to reduce the costs and enhance the system accuracy. The performance of the proposed observer is analyzed through simulations considering measurement noise and different stack-current variations. The results show that the algebraic observer estimates in finite time and robustly the oxygen-excess ratio.Peer ReviewedPostprint (author's final draft

A Predictive power control of Doubly Fed Induction Generator for Wave Energy Converter in Irregular Waves

International audienceIn last decades, renewable energy resources are considered as an alternative energy resource to the world's excessive energy demand. An extremely abundant and promising source of energy exists in oceans. Currently, there are several wave energy converters to harness this energy. Some of them, as in tidal applications, use the Doubly-fed induction generator. This paper deals then with a predictive power control of this generator based Wave Energy Converter under irregular wave climate which is modeled as time series elevation from using Bretschneider spectra. In the proposed control approach, the predicted output power was calculated using a linearized state-space model. The DFIG-based WEC power tracking performances further illustrates the dynamic features of the proposed predictive power control approach

Ocean Wave Converters: State of the Art and Current Status

International audienceSolutions to today energy challenges need to be explored through alternative, renewable and clean energy sources to enable a diverse energy resource plan. An extremely abundant and promising source of energy exists in oceans. Ocean energy exists in many forms. Among these forms, significant opportunities and benefits have been identified in the area of ocean wave energy extraction, i.e., harnessing the wave motions and converting them into electrical energy. Regarding this emerging and promising area of research, this paper presents ocean wave energy fundamentals and then reviews the fundamental concepts and the main projects around the world. It also reports issues regarding electrical generator topologies associated to wave energy converters

Nonlinear adaptive sliding mode control of a powertrain supplying fuel cell hybrid vehicle

International audienceThis paper presents an adaptive sliding mode based switching scheme for controlling DC-DC hybrid powertrain for propulsion of a Fuel Cell / Supercapacitor hybrid vehicle. After modeling the powertrain, a new approach to determine a nonlinear sliding surface ensuring stability of the DC/DC Boost converter is discussed. This was achieved without introducing the equivalent control aspect after transforming the instantaneous model of the Boost in a suitable form. The presented technique is also applied for trajectories tracking in the entire powertrain, which includes a dc/dc Boost converter associated to Fuel Cell stack and another Bidirectionnel dc/dc converter associated to the supercapacitor bank, which are both working in parallel to provide electricity propelling the vehicle. The control scheme is tested with driving cycle example through simulation

Nonlinear observer design for PEM fuel-cell systems using first-order sliding mode techniques

This paper presents a nonlinear observer design for Proton Exchange Membrane Fuel-Cell (PEMFC) systems. The aim of the proposed observer is to reconstruct the oxygen excess ratio through the estimation of their relevant states in real time from the measurement of the supply manifold air pressure. A First-Order Sliding Mode (FOSM) differentiation method is adopted to estimate, in finite time, the time derivative of the supply manifold air pressure. By means of the output-state inversion model, the relevant states are reconstructed. The objective of the proposed appproach is to minimize the use of additional sensors in order to reduce the costs and enhance the system accuracy. The performance of the proposed observer is analyzed through simulations considering measurement noise and different stack-current variations. The results show that the nonlinear observer properly estimates in finite time and robustly the oxygen excess ratio.Peer ReviewedPostprint (author's final draft

Air flow regulation in fuel cells: an efficient design of hybrid fuzzy-PID control

This paper presents a hybrid fuzzy-PID controller for air flow supply on a Proton Exchange Membrane fuel cell (PEMFC) system. The control objective is to adjust the oxygen excess ratio at a given setpoint in order to prevent oxygen starvation and damage of the fuel-cell stack. The proposed control scheme combines a fuzzy logic controller (FLC) and classical PID controller with a view to benefit the advantages of both controllers. The results show that the proposed technique performs significantly better than the classical PID controller and the FLC in terms of several key performances indices such as the Integral Squared Error (ISE), the Integral Absolute Error (IAE) and the Integral Time-weighted Absolute Error (ITAE) for the closed-loop control system.Peer ReviewedPostprint (author's final draft

Robust fuzzy sliding mode control for air supply on PEM fuel cell system

In this paper, an adaptive fuzzy sliding mode controller is employed for air supply on proton exchange membrane fuel cell (PEMFC) systems. The control objective is to adjust the oxygen excess ratio at a given set point in order to prevent oxygen starvation and damage to the fuel-cell stack. The proposed control scheme consists of two parts: a sliding mode controller (SMC) and fuzzy logic controller (FLC) with an adjustable gain factor. The SMC is used to calculate the equivalent control law and the FLC is used to approximate the control hitting law. The performance of the proposed control strategy is analysed through simulations for different load variations. The results indicated that the adaptive fuzzy sliding mode controller (AFSMC) is excellent in terms of stability and several key performance indices such as the integral squared error (ISE), the integral absolute error (IAE) and the integral time-weighted absolute error (ITAE), as well as the settling and rise times for the closed-loop control system.Peer ReviewedPostprint (author's final draft

Algebraic observer-based output-feedback controller design for a PEM fuel cell air-supply subsystem

© 20xx IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.In this paper, an algebraic-observer-based output-feedback controller is proposed for a Proton Exchange Membrane Fuel Cell (PEMFC) air-supply subsystem, based on both algebraic differentiation and sliding-mode control approaches. The goal of the design is to regulate the Oxygen Excess Ratio (OER) towards its optimal setpoint value in the PEMFC air-supply subsystem. Hence, an algebraic estimation approach is used to reconstruct the OER based on a robust differentiation method. The proposed observer is known by its finite-time convergence and low computational time compared to other observers presented in the literature. Then, a twisting controller is designed to control the OER by manipulating the compressor motor voltage. The parameters of the twisting controller have been calculated by means of an off-line tuning procedure. The performance of the proposed algebraic-observer-based output-feedback controller is analyzed through simulations for different stack-current changes, for parameter uncertainties and for noise rejection. Results show that the proposed approach properly estimates and regulates the OER in finite-time.Peer ReviewedPostprint (author's final draft

Integral Sliding Mode Control for Trajectory Tracking of Wheeled Mobile Robot in Presence of Uncertainties

Wheeled mobile robots present a typical case of complex systems with nonholonomic constraints. In the past few years, the dominance of these systems has been a very active research field. In this paper, a new method based on an integral sliding mode control for the trajectory tracking of wheeled mobile robots is proposed. The controller is designed to solve the reaching phase problem with the elimination of matched disturbances and minimize the unmatched one. We distinguish two parts in the suggested controller: a high-level controller to stabilize the nominal system and a discontinuous controller to assess the trajectory tracking in the presence of disturbances. This controller is robust during the entire motion. The effectiveness of the proposed controller is demonstrated through simulation studies for the unicycle with matched and unmatched disturbances

Predictive Power Control of Doubly-Fed Induction Generator for Wave Energy Converters

International audienceSolutions to today energy challenges need to be explored through alternative, renewable and clean energy sources to enable a diverse energy resource plan. An extremely abundant and promising source of energy exists in oceans. There are several wave energy converters to harness this energy. Some of them, as in tidal applications, use the Doublyfed induction generator (DFIG). This paper deals then with a model-based predictive power control of a DFIG-based Wave Energy Converter (WEC). In the proposed control approach, the predicted output power was calculated using a DFIG linearized state-space model. The DFIG-based WEC power tracking performances further illustrates the dynamic features of the proposed predictive power control approach