Applied mathematical software and a web-based interactive handbook for thermal engineering: Problems and solutions

A new area in information technology (IT) for power engineering, interactive Internet handbooks for thermal and power engineering, is considered. The already available handbooks are posted at http://twt.mpei.ac.ru/pvhb, http://twt.mpei.ac.ru/tthb, http://twt.mpei.ac.ru/gdhb, http://www.thermophysics.ru, and www.edata-center.com.     

Using genetic algorithm and TOPSIS technique for multiobjective reactive power compensation

A new approach to solve the multiobjective reactive power compensation (RPC) problem is presented. It is based on the combination of genetic algorithm (GA) and the ?-dominance concept. The algorithm maintains a finite-sized archive of nondominated solutions (Pareto solution) which gets iteratively updated in the presence of new solutions based on the concept of ?-dominance. The use of ?-dominance makes the algorithms practical by allowing a decision maker (DM) able to control the resolution of the Pareto set approximation according to his needs. The proposed approach is suitable to RPC problem where the objective functions may be ill-defined and having nonconvex Pareto-optimal front. It gives a reasonable freedom in choosing compensation devices from the available commercial devices. It may save computing time in cases of small archive.     

Determination of piezoelectric parameters from the measured natural frequencies of a piezoelectric circular plate

Due to the complexity of electro-elastic coupling characteristics in piezoelectric materials, some elastic, dielectric and piezoelectric parameters are difficult to measure. Usually, these parameters are determined by assuming that all other parameters remain constant during the measurement. However, the interactive effect between material properties makes this assumption not always true. In this study, the measured natural frequencies of the specified circular piezoelectric plate are used to extract these parameters simultaneously. In other words, all these parameters are determined with consideration of the interactive electro-elastic coupling effect.

The analytic model of a free-free circular piezoceramic plate was derived and solved to establish the relationship between natural frequencies and their material parameters. In order to cover most of the parameters, the out-of-plane (non-symmetric transverse) and in-plane (symmetric extensional) modes are considered.

The genetic algorithm is employed to determine most of the elastic, dielectric and piezoelectric parameters from a least square error between the calculated and measured natural frequencies. The numerical results derived from the parameters proposed in this work reveal that they coincide well with the measured data. In other words, the proposed method for extracting piezoelectric parameters is both feasible and effective.     

Analytical formula of induced electric fields in a spherical conductor by an ELF dipole magnetic field source

An analytical formula of induced electric field E in a spherical conductor by an ELF dipole magnetic field source is mathematically derived in vector form based on the equivalent mutlipole moment method with reexpansion technique (RE‐EMMM), where M _‖ and are parallel and perpendicular components of M , respectively. The validity of the formula is confirmed in the following three ways: (i) the derivation of the formula from the Sarvas equation with the reciprocity theorem derived by Eaton; (ii) the convergence of the formula to that of homogeneous magnetic field when M _‖ is located at the infinite distance; (iii) comparison of the analytical solutions with numerical solutions by RE‐EMMM. Furthermore, a formula for the trajectory, which satisfies E = 0 , is derived for the field by M _‖. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 166(3): 8– 17, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20739     

Hyundai,UTC Fuel Cells collaborating on all-weather FCV

Korea’s Hyundai Motor Co and Connecticut-based UTC Fuel Cells have agreed to collaborate on the development of a new automotive fuel cell power plant that can operate in freezing conditions, then integrate it into a Hyundai sports utility vehicle (SUV). The problem of starting a fuel cell once the water in the system has frozen remains one of the key hurdles in the development of automotive fuel cells.This is a short news story only. Visit www.re-focus.net for the latest renewable energy industry news.     

Ineos Chlor launches bipolar plate system

UK-based Ineos Chlor has commercially launched PEMcoat FCP, which it claims gives greatly improved metal plate performance in hydrogen PEM and DMFC stack technologies for high power density, long-lifetime stacks.Visit www.re-focus.net for the latest renewable energy news     

Comparative Assessment of PV Plant Performance Models Considering Climate Effects

The climate conditions can affect the accuracy of photovoltaic (PV) system performance models that can be used for monitoring and diagnostic purposes. In this paper, an improved energetic physical model has been considered to estimate the power production of PV systems. Specifically, in this model, special attention has been devoted to the modeling of optical losses (IAM losses) and to the inverter efficiency under low-power conditions.

A comparative analysis of the proposed model applied to two PV plants installed respectively in the north of Denmark (Aalborg) and in the south of Italy (Agrigento) has been performed. The different ambient, operating and installation conditions allow to understand how these factors impact the precision and effectiveness of such model. The experimental results show that the proposed model allows us to have a good estimation of AC power in terms of Relative Mean Bias Error, normalized Root-Mean-Square Error, and the Correlation Coefficient. Further in order to have the possibility to analyze and compare the performance of the studied PV plants with others, the efficiency of the systems has been estimated by both Performance Ratio and Corrected Performance Ratio.     

Testing protocol for composite bipolar plates

The US Fuel Cell Council has released details of its new ‘testing protocol’ for composite bipolar plates– the first of several protocols it has under development, and one of the first open technical collaborations in the industry.Visit www.re-focus.net for the latest renewable energy news     

Nickel alloy catalyst for cheap, ‘green’ hydrogen

Scientists at the University of Wisconsin at Madison in the US have developed a hydrogen-producing catalyst that uses cheaper materials and yields fewer contaminants than current processes, while extracting hydrogen from common renewable plant sources.This is a short news story only. Visit www.re-focus.net for the latest renewable energy industry news     

Palcan receives Voller order for stacks

Vancouver-based Palcan Fuel Cells has received confirmation of an order for 100 fuel cell stacks from Voller Energy in the UK. The 120 We PEM stacks will be delivered over the next 12 months.This is a short news story only. Visit www.re-focus.net for the latest renewable energy industry news.     

FCE,PPL complete DFC installation for Coast Guard,new certifications

Connecticut-based FuelCell Energy and its US distribution partner, PPL EnergyPlus in Massachusetts, have completed the installation of a Direct FuelCell^® (DFC^®) power plant at one of the largest US Coast Guard air stations on the East Coast.Visit www.re-focus.net for the latest renewable energy industry news     

IdaTech installs propane fuel cell system for off-grid field tests

Bend, Oregon-based IdaTech has installed a 3.6 kWe propane-fueled fuel cell system in the Cascade mountain range, near the company’s facility, for field testing and evaluation in an off-grid telecom application. The project was awarded to IdaTech as an additional funding grant provided by the Propane Education and Research Council (PERC) to accelerate the development of LPG fuel cell systems.This is a short news story only. Visit www.re-focus.net for the latest renewable energy industry news.     

EU roadmap towards sustainable H2 economy

The European Commission has launched its European Hydrogen & Fuel Cells Technology Partnership, maintaining the momentum of the long-term vision it unveiled at a special conference in Brussels in June [FCB, July]. The Partnership, which will be steered by an Advisory Council, will now devise a Hydrogen Research Strategic Agenda.Visit www.re-focus.net for the latest renewable energy news     

Global downsizes fuel cell division

Calgary-based Global Thermoelectric has reduced its fuel cell division workforce by approximately one-third, or 47 employees, to reduce annual R&D expenditure by approximately C$5m (US$3.7m). The announcement is consistent with the company’s strategy to focus on core technology development while maintaining prototype system capability.Visit www.re-focus.net for the latest renewable energy industry news     

Shell Hydrogen,Vandenborre developing home H2 refueling

Dutch-based Shell Hydrogen has signed a development, marketing and sales agency agreement with Vandenborre Technologies, the Belgian manufacturer of electrolysis-based hydrogen generators recently acquired by Toronto-based Stuart Energy Systems. The agreement gives Shell Hydrogen access to Vandenborre’s electrolyzer-based hydrogen home refueling products.This is a short news story only. Visit www.re-focus.net for the latest renewable energy industry news.     

FCE to acquire Global,synergies in high-temp fuel cells

Connecticut-based FuelCell Energy, the acknowledged leader in commercializing molten carbonate fuel cells for stationary power, has entered into a definitive agreement to acquire Canadian solid oxide fuel cell developer Global Thermoelectric. Global has terminated its combination agreement with California-based Quantum Technologies.This is a short news story only. Visit www.re-focus.net for the latest renewable energy industry news     

and filter design for polytopic continuous‐time Markov jump linear systems with uncertain transition rates

This paper addresses the problems of and full‐order filter design for continuous‐time Markov jump linear systems subject to uncertainties. Different from the available methods in the literature, the main novelty of the proposed approach is the possibility of computing bounds to the and norms of the augmented system composed by the uncertain Markov jump linear system plus the robust filter through Lyapunov matrices depending polynomially on the uncertainties affecting independently the matrices of each operation mode and the transition rate matrix. By means of a suitable representation of the uncertainties, the proposed filter design conditions are expressed in terms of linear matrix inequality relaxations associated with searches on scalar parameters. As an additional flexibility, the conditions can be used to synthesize filters with partial, complete, or null Markov mode availability. Numerical experiments illustrate that the proposed approach is more general and can be less conservative than the available methods. Copyright © 2014 John Wiley & Sons, Ltd.     

Quantum fluctuation in affine optimal control systems

Quantum mechanical wave functions are shown to approximate optimal feedback laws of affine control systems, when we set the absolute values of the terminal wave functions positive and with no singular dependence on a control constant H_R, which is similar in position to the action constant introduced by Planck to explain quantum phenomena. Calculation of the wave functions makes use of the path integral representation that we approximate at stationary phase. The phases of the wave functions approximate in H_R→0 to Hamilton–Jacobi value functions, because quantum mechanical fluctuation vanishes in the limit. It is simple to take the terminal absolute value function that meets the condition of having no singularity at H_R=0. The terminal absolute value function without any dependence on the constant H_R apparently satisfies the no‐singularity condition. Although we restrict ourselves to scalar systems, generalization to systems with higher dimensionality is straightforward. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 161(4): 29–37, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20521     

Wireless Power Transmission Model Using Coaxial Helical Solenoid Coils for Powering Utility Equipment

Mid-range low-power wireless power transmission systems using resonant–inductive coupling have recently been in use for powering a variety of household gadgets. A modified resonantly coupled system for a wireless power transmission system using coaxial helical solenoid coils is presented, using distributed parameters predominantly at high frequency. The proposed system is reduced using circuit transformations, and the operating power transfer efficiency under varying conditions of source and load are derived. The model is tested with an experiment consisting of a home lighting utility load for the resonant frequency of 1.2 MHz. The experimental results are in close agreement with the proposed analytical model for varying distances between the transmitter and receiver. A comparison of the operating power transfer efficiency of the proposed model with resonantly and inductively coupled models for varying distances between the transmitter and receiver is presented. Maximum power transfer efficiency by matching source and load resistances is simulated using the RF Toolbox (http://www.mathworks.in/products/rftoolbox) on the proposed, resonantly coupled, and inductively coupled models. The simultaneous conjugate-matching technique for increasing the power transfer efficiency to near 100% is also presented.