The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Coaxial magnetic gears with permanent magnets have a very simple structure and performance comparable to that of mechanical gears. The paper describes an analytical simplified approach for the analysis and design procedure. The mathematical model is one-dimensional: only the variation of electromagnetic quantities as function of angular position is considered and the permanent magnets are modeled...
The paper concerns the dimensioning of “zero” emission power-train architecture of an urban electrical mini-bus fed by a hybrid power unit based on hydrogen fuel-cells and a flywheel energy storage system. Performance numerical analyses are carried out by using fuel-cell experimental data and by modeling the mini-bus running along a L'Aquila city (Italy) urban drive cycle, experimentally tested in...
The behavior of a magnetic gear which employs rare earth magnets is analyzed; the magnetic gear allows the power to be transmitted by transforming speed and torque. An analytical simplified approach for the analysis of the considered magnetic gear is used in this paper. The approach can be suitable for design aims. The mathematical model is one-dimensional: only the variation of electromagnetic quantities...
This paper presents the design and application of hybrid power train for city bus with zero greenhouse emissions and high work efficiency. The vehicle system configuration is based on two separately electric driven wheels powered by an hybrid unit composed by a hydrogen fuel cell and flywheel energy storage system. Numerical models were built to simulate the powertrain components and to downsize the...
The performance and the reliability of the power transformers are critical parameters for the electric power production, transmission and utilization. In the last years diagnostic techniques have been widely utilized to improve the safety and to reduce the maintenance costs of power transformers. The Bticino group had recently acquired the plant in Castellalto, Italy, from the Zucchini EMM, that is...
Today the application of PEM (Polymer Electrolyte Membrane) fuel cell stack in the automotive field is a topic on central interest. Unfortunately, a PEM fuel cell stack cannot directly supply variable speed drives because of their non-linear behaviour in dynamic conditions. This paper is mostly concerned with the sizing of the supply system, PEM fuel cell-supercapacitor-battery pack, of an electric...
The electrical voltage fluctuations and their negative effects on industrial and domestic apparatuses represent one of the most interesting topics of research in the field of Power Quality. Early studies investigated the behavior of different types of lamps in presence of voltage amplitude modulations and the design of light flicker meters. In realistic conditions, the observed voltage fluctuations...
Today the application of PEM (polymer electrolyte membrane) fuel cell stack in the automotive field is a topic on central interest. Unfortunately, a PEM fuel cell stacks cannot directly supply variable speed drives because of their non-linear behaviour in dynamic conditions. This paper is mostly concerned with the performance evaluation of the PEM fuel cell-supercapacitor system during repetitions...
Today the application of PEM (polymer electrolyte membrane) fuel cell stack in the automotive field is a topic on central interest. Unfortunately, a PEM fuel cell stack cannot directly supply variable speed drives because of their non-linear behaviour in dynamic conditions. This paper is mostly concerned with the performance evaluation of the PEM fuel cell-supercapacitor system during repetitions...
The measurement of both electric power and energy, especially in non sinusoidal conditions, is today a still open research problem in the metrology community. Harmonic distortion, noise, transients, over-voltages and voltage dips have increased the difficulty in achieving accurate measurements. Besides, many of non-active power component definitions that have been proposed cannot be implemented in...
Speaking of linear machines, the waveform of the electromagnetic quantities is not sinusoidal, i.e. currents are not sinusoidal in time and magnetic field distributions are not sinusoidal in space, because of the asymmetry of both iron magnetic structure and windings. The performance of linear machines can be studied by means of one-dimensional or two- dimensional mathematical models. In both cases...
The adoption of fuel cells for industrial applications, transportations and home power generation has widely increased during recent years. The performance evaluation of a fuel cell system requires both static and dynamic model, especially for the automotive applications which involve step variations of electric load. Besides, current step variations abruptly change the fuel cell voltage causing a...
The adoption of fuel cells for industrial applications, transportations and home power generation has widely increased during recent years. The performance evaluation of a fuel cell system requires both static and dynamic model, especially for the automotive applications which involve step variations of electric load. Besides, current step variations abruptly change the fuel cell voltage causing a...
The voltage fluctuations of the electrical power supply can generate many undesirable effects on both industrial and domestic apparatuses. The aim of this paper is the evaluation of the effects of the low-frequency voltage amplitude modulation on induction motors. An experimental analysis has been applied to a three phase, 7.5 kW induction motor with the adoption of an ad hoc system for the EMC low-frequency...
A modified one-dimensional mathematical model based on the space-vectors theory is used to analyse the performance of permanent magnet linear synchronous motors with starting and dumping sheet. The end-effects are taken into account by assuming that the length of the iron core is infinite and the length of the armature winding is finite. The resulting differential equation set allows both steady state...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.