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.
In the present paper, a comparison among different types of urban mass transport systems, which can be implemented for medium-sized cities, is reported. For each mobility system, advantages and disadvantages, in terms of transport capacity and environmental impact, are highlighted. Then the focus is pointed on the trolley-bus solution. A real case study of deployment of this type of mobility system,...
In this manuscript, we propose to compare two novel sensorless strategies control of doubly fed induction generator (DFIG) based on the output electrical power, and rotor and stator current with stator voltage measurement. The performances of the proposed sensorless strategies are compared. The developed control strategy was tested for different operating modes: real wind speed with balanced and unbalanced...
The decrease of fossil energy and increase of available renewable energy places the Electric Vehicle (EV) into a new point of view as a modern transport system for individual mobility. Whether you live in a town or on the countryside different energy sources within EVs offer a wide range of usability. Anyway the resulting energy being used by the engine is electrical energy [1], [2].
Much of the energy generated today is produced by centralized power plants using fossil fuels, hydropower or nuclear power, with energy being transmitted and distributed over long distances to the consumers. The electricity networks of the future will have to accommodate large scale distributed generation including renewable energy sources and residential micro-generation. Therefore solutions must...
Electronic components performances are influenced by many factors such as working conditions, load requirements, devices technologies, package types, ambient temperature, etc. In this paper a study of the temperature influence on components parameters in Distributed Maximum Power Point Tracking (DMPPT) converters is made. In photovoltaic systems a crucial task is represented by converters energetic...
In this study novel solutions are presented for challenge subjects such as the weighting of wind energy parameters and classifying of meteorological data that should be consider in the installation of wind turbines. For this purpose, the relationships between the meteorological parameters and wind turbines are explored with an intuitive k-Nearest Neighbor algorithm. Thus, the effects of meteorological...
In this paper, a control method for a Wind Energy Conversion System (WECS) utilizing a Squirrel Cage Induction Generator (SCIG) is presented. Aims of the control are both maximum wind power harvesting and minimization of the SCIG power loss, thus achieving maximum power production on any wind speed. The SCIG is connected to the utility grid through two back-to-back converters. The first converter...
With the increasing nominal power of wind energy converters, an optimized management, a higher level of efficiency and reduced costs are needed. In search of suitable generator systems for wind turbines in the MW class, the permanent-magnet synchronous machine as a generator moves to the focus of current discussions. The Rotor and its blades are able to oscillate due to various dynamic loads a wind...
Massive utilization of fossil fuels presents serious environmental threats. In this context, today the development of renewable energies is an urgent issue. Due to the stochastic nature of renewable energy sources an energy storage is needed in renewable energy generation systems. Hydrogen-based energy storage system or hydrogen buffer can help to stabilize unregulated renewable energy generation...
High voltage switch unit on a base of isolated gate bipolar transistors (IGBT) with operating voltage of 4.5 kV and capability of pulse width control is developed and investigated. The start-stop circuit of IGBT gates control lets the switch to be open for near unlimited periods of time up to be continually open at constant nanosecond delay time.
Real-time simulation of Power Electronic Converters (PECs) allows a first realistic validation of their digital controllers and avoids experimental constrains (cost, damage risks, reliability …). However, to increase the realism of validation, the real-time model has to reach a high level of accuracy. This objective is balanced by, among others, the computational time ensured by the used digital technology...
Stand-alone power systems are a challenging option to supply remote equipments in many applications. They include renewable energy generators whose intermittent power supply requires an appropriate energy storage component to balance the power mismatch between the generation and the demand. Batteries are the obvious choice for this purpose. However, the irregular fluctuations and hard transients would...
In this paper a new Z-source frequency converter with silicon carbide (SiC) components is presented. Both, the motor side and the line side converter, contain SiC-VJFETs using the reverse-conducting capability for freewheeling. The application of SiC transistors with their low switching losses, allows high switching frequencies (up to 125 kHz), so the volume of the DC-link and filter components is...
This paper presents a three-phase integrated inverter suitable for stand-alone and grid-connected applications. Furthermore, the utilization of the special features of the tri-state coupled with the new space vector modulation allows the converter to present an attractive degree of freedom for the designing of the controllers. Additionally, the control is derived through dq0 transformation, all the...
This paper studies the performance of a Wind Energy Conversion System (WECS) with an induction generator under various start-up control techniques. The capability of self-excitation of the induction generator using three control techniques is examined. The generator is connected to the power grid by means of a fully controlled frequency converter which consists of a pulse-width modulation (PWM) rectifier,...
Research of grid connected wind turbines has gained great interest in the recent years. This led to introduce guidelines and regulations regarding the connection of large wind farms to the electrical network. One of such guidelines is low voltage ride-through capability (LVRT). In this paper, a survey on recent LVRT solutions for permanent magnet synchronous generators (PMSG) is carried out along...
The influence has been studied of the absorbing layers to the efficiency of solar drying chamber. Proposed solar drying chamber walls are composed of translucent coating from outside and absorbing layers are placed its inside. A technique is used for calculating the effective value of transparent wall's transmittance and investigated average system efficiency with effective value of wall transmittance...
Collection schemes based on DC technologies appear as a possible alternative to present layouts of offshore wind farms to reduce the installation and operational costs. Within these internal DC collection schemes, series connection can be particularly attractive when a sufficiently high number of units are cascaded in order to reach a voltage level suitable for direct HVDC transmission. Power electronics...
The sources of non-self connection to the grid and non-linear loads produces high harmonic currents. This paper presents a study of a harmonic compensation system and reactive disturbances using a photovoltaic generator. The system consists of a voltage inverter which acts as an active filter and a photovoltaic generator parallel as a source of electrical energy. The main simulation and principal...
This paper deals with a simulation modeling of a mechatronic system as multi-body system with an active damping element. Modeled mechatronic system is based on a mechanical multi-body model with flexible parts, model of actuator, sensor and a control system. A development process of the active damping model and the control system is presented in this paper. This development process of mechatronic...
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.