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

Rapid Prototyping of PEM Fuel Cell Bi-Polar Plates using 3D Printing and Thermal Spray Deposition

This article presents the results of exploratory research on novel methods for the fabrication of functional, metallic, gas flow, bi polar plates (BPP) for use in proton exchange membrane fuel cells (PEMFC). Low cost, high speed, additive manufacturing methods that combine 3D printing (3DP) and thermal spray (TS) technologies are described. Functional flow plates were manufactured by creating 3DP patterns and then depositing, and releasing, dense metals with TS methods. The new method yields dense metal plates, with interesting options for material choices and complex designs.Mechanical Engineerin

Transformasi Pekan Parit Raja: kajian terhadap kesejahteraan hidup masyarakat

Isu utama yang dibangkitkan dalam kajian ini adalah mengenai isu kesejahteraan hidup masyarakat ekoran transformasi yang berlaku di Pekan Parit Raja dan kesannya. Transformasi pembangunan yang berlaku di pekan kecil pada asasnya menunjukkan pencapaian positif dalam pelbagai sudut mencakupi perkembangan ekonomi, perindustrian, prasarana dan perumahan. Namun turut memberi kesan kepada persekitaran fizikal. Kesan daripada keadaan itu turut membawa ke arah kemerosotan serta memberi tekanan yang kuat terhadap kesejahteraan hidup masyarakat setempat. Objektif kajian ini ialah (i) meninjau perkembangan pembangunan di Pekan Parit Raja, (ii) mengenalpasti perubahan sosio ekonomi penduduk setempat, (iii) mengenalpasti keperluan penduduk setempat mengikut perkembangan semasa dan (iv) membentuk indeks penunjuk kesejahteraan hidup bagi masyarakat Pekan Parit Raja. Skop kajian tertumpu di Pekan Parit Raja dengan tumpuan terhadap transformasi pembangunan yang dialami dari segi perkembangan fizikal, sosial dan ekonomi. Responden yang terpilih terdiri daripada wakil Pihak Berkuasa Tempatan, wakil komuniti dan masyarakat setempat. Kajian dijalankan berdasarkan kepada pengumpulan data primer dan sekunder. Sejumlah 367 responden telah dipilih secara persampelan rawak bersrata. Data yang dikumpul telah dianalisis menggunakan program SPSS. Analisis kajian mendapati perubahan ruang ekonomi yang berlaku di Pekan Parit Raja adalah sangat ketara. Hasil kajian menunjukkan keluasan had pembangunan di Pekan Parit Raja telah meningkat sebanyak 2.51% antara tahun 1998 sehingga tahun 2003 dan tertinggi berbanding lima (5) bandar utama lain. Faktor pembangunan sosio ekonomi yang positif menyebabkan unjuran penduduk dijangka mencapai sehingga 9.9% sehingga tahun 2020. Sebanyak 53.8% responden telah berjaya meningkatkan pendapatan sehingga hampir sekali ganda dalam tempoh 20 tahun. Sebahagian besar responden pula berkemampuan dari segi pemilikan perumahan dan kereta masing-masing dengan peningkatan sehingga 86.6% dan 98.0% pada sekitar tahun 2010. Ianya sangat berbeza dengan 20 tahun lepas. Walau bagaimanapun, 72.5% responden menyatakan beberapa keperluan perlu ditambah atau diperbaiki dengan jalan raya merupakan keperluan utama. Pada masa yang sama, 75.7% responden menyatakan jenis keperluan yang paling penting perlu disediakan adalah perpustakaan awam. Dapatan keseluruhan kajian akhirnya telah membentuk indeks penunjuk kesejahteraan hidup dari aspek ekonomi, kualiti perumahan, keharmonian sosial dan alam sekitar kesan transformasi pembangunan ke atas kesejahteraan hidup masyarakat setempat. Beberapa cadangan telah dikemukakan agar pembangunan yang membawa perubahan kepada sosio ekonomi dan persekitaran seharusnya mengambil kira kesejahteraan hidup masyarakat dan kelestarian alam sekitar untuk mencapai kualiti hidup yang lebih baik di masa akan datang

Parameter estimation algorithm of H-100 PEM fuel cell

Best Oral Communication Award for Young Authors, atorgat pel comitè científic HYCELTEC 2019Polymer electrolyte membrane fuel cells (PEMFCs) have been recognized as one of the most promising eneygy conversion devices for commercial application due to their specific advantages, such as low operation temperature, zero pollutant emission, and high efficiency, etc. Since PEMFC is a highly nonlinear system and some parameters are related to the operation condition, most existing models are difficult to accurately predict the PEMFC characteristics. Thus, it is necessary to exploit parameter estimation methods for PEMFC to online determine the unknown model parameters by using easily measurable data to obtain concrete models. Most of the parameter estimations schemes for PEMFC have been designed based on intelligent optimization techniques. However, optimization methods cannot address the estimation problem online since they focus exclusively on offline searching procedure, which introduces heavy computational costs in the practical implementation and thus cannot be used in the real-time applications. Therefore, this paper aims to exploit real-time adaptive parameter estimation methods for a nonlinear parametric PEMFC system.Peer ReviewedAward-winningPostprint (author's final draft

Load profile effect on durability of proton exchange membrane fuel cells

Proton Exchange Membrane Fuel Cells (PEMFC) are a promising technology for substitution of hydrocarbon powerdrives and battery based electrical supply systems. However, below-required durability is still an important factor that hinders its widespread use, thus, novel operating approaches are required to surpass this shortcoming. The present abstract presents a line of research directed towards the of analysis and definition of load profile characteristics in order to design controllers and operation strategies that optimize cell efficiency and durability. Degradation of the catalyst layer, commonly composed of platinum supported on carbon (Pt/C), mainly due to platinum loss by oxidation/dissolution and the resulting reduction of Electrochemical Active Surface Area (ECSA), is the main issue reducing the durability of PEMFC.Peer ReviewedPostprint (author's final draft

Experimental evaluation into novel, low cost, modular PEMFC stack

Attribution-NonCommercial-NoDerivs 3.0 Unported (CC BY-NC-ND 3.0)The Polymer Electrolyte Membrane Fuel Cell (PEMFC), despite being regarded as an ideal replacement to the internal combustion engine, is still not an economically attractive pri-mover due to a number of key challenges that have yet to be fully resolved; some of which include degradation to cell components resulting in inadequate lifetimes, specialised and costly manufacturing processes and poor gravimetric/volumetric energy densities. This paper presents a novel stack concept which removes the conventional bi polar plate (BPP), a component that is responsible for up to 80% of total stack weight and 90+% of stack volume in some designs. The removal of said component not only improves the volumetric and gravimetric energy density of the PEMFC stack but drastically reduces the cost of the stack by removing all costly manufacturing processes associated with PEMFC component machining while the functionality of the traditional BPP is still retained by the unique stack design. The stack architecture is first presented and then the characterisation of the PEMFC is shown over a wide range of operating scenarios. The experimental studies suggest that the performance of the new design is comparable to that of traditional stacks but at significantly less cost price.Final Published versio

Nonlinear observation in fuel cell systems: a comparison between disturbance estimation and High-Order Sliding-Mode techniques

© . This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/This paper compares two Nonlinear Distributed Parameter Observers (NDPO) for the observation of a Proton Exchange Membrane Fuel Cell (PEMFC). Both NDPOs are based on the discretisation of distributed parameters models and they are used to estimate the state profile of gas concentrations in the anode and cathode gas channels of the PEMFC, giving detailed information about the internal conditions of the system. The reaction and water transport flow rates from the membrane to the channels are uncertainties of the observation problem and they are estimated throughout all the length of the PEMFC without the use of additional sensors. The first observation approach is a Nonlinear Disturbance Observer (NDOB) for the estimation of the disturbances in the NDPO. In the second approach, a novel implementation of a High-Order Sliding-Mode (HOSM) observer is developed to estimate the true value of the states as well as the reaction terms. The proposed observers are tested and compared through a simulation example at different operating points and their performance and robustness is analysed over a given case study, the New European Driving Cycle.Peer ReviewedPostprint (author's final draft

Nonlinear predictive control for durability enhancement and efficiency improvement in a fuel cell power system

© . This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/In this work, a nonlinear model predictive control (NMPC) strategy is proposed to improve the efficiency and enhance the durability of a proton exchange membrane fuel cell (PEMFC) power system. The PEMFC controller is based on a distributed parameters model that describes the nonlinear dynamics of the system, considering spatial variations along the gas channels. Parasitic power from different system auxiliaries is considered, including the main parasitic losses which are those of the compressor. A nonlinear observer is implemented, based on the discretised model of the PEMFC, to estimate the internal states. This information is included in the cost function of the controller to enhance the durability of the system by means of avoiding local starvation and inappropriate water vapour concentrations. Simulation results are presented to show the performance of the proposed controller over a given case study in an automotive application (New European Driving Cycle). With the aim of representing the most relevant phenomena that affects the PEMFC voltage, the simulation model includes a two-phase water model and the effects of liquid water on the catalyst active area. The control model is a simplified version that does not consider two-phase water dynamics.Peer ReviewedPostprint (author's final draft

Ion exchange membranes based upon crosslinked sulfonated polyethersulfone for electrochemical applications

Synthesis and characterization of new ion exchange membranes made from chlorosulfonated polyethersul- fone (SO2Cl-PES) crosslinked by polyaminated crosslinking reagents have been performed. Two examples are described: one crosslinked by hexane diamine, the other by amino-polyethersulfone (NH2-PES). Sulfonated polyether sulfone (S-PES) and NH2-PES have similar chemical structures that allow compatibility. Surpris- ingly enough, better results were obtained using amino-polyethersulfone. The best results have been obtained using SO2Cl-PES with 1.3 SO2Cl group per monomer unit crosslinked by 0.2 equivalent of NH2-PES. The membranes, less brittle than pristine SPES and insoluble in solvents such as DMAc, were characterized by TGA, DMA, DSC, ionic conductivity, transport numbers, and water swelling. The results showed that these membranes presented very promising performances for use in Proton Exchange Membrane Fuel Cells