Search results for "Dc converter"

Power losses comparison between Silicon Carbide and Silicon devices for an isolated DC-DC converter

2021

In recent years, new efficient power devices have been implemented. Silicon Carbide has replaced silicon as regards the production and the utilization of many devices, such as MOSFETs, diodes, IGBTs and many others. SiC devices are characterized by a low reverse recovery charge, high carrier saturation velocity, by which it is possible to work at high frequency, and high breakdown voltage. Thanks to the great thermal conductivity and the wide bandgap, these devices can operate at high temperature and reach high voltages and currents. What is important to stress is the fact that power losses in SiC devices are lower than the silicon ones. These are the reasons why these devices are utilized …

NON-LINEAR INDUCTOR CONTRIBUTION TO HARMONIC SPECTRUM IN POWER CONVERTERS

The paper investigates the harmonic content in DC/DC power converters where the inductor is operated in the non-linear region. This operation is often exploited to use lighter and cheaper inductors; as a drawback, an increasing number of harmonics is noticeable. A theoretical analysis is proposed. It is based on a polynomial model of the inductor used in a boost converter. Results are given by the spectra of the output voltage performed on a circuit prototype.

Nonlinear Modeling of DC/DC Converters Using the Hammerstein's Approach

2007

This paper deals with the modelling of highly nonlinear switching power-electronics converters using black-box identification methods. The duty cycle and the output voltage are chosen, respectively, as the input and the output of the model. A nonlinear Hammerstein-type mathematical model, consisting of a static nonlinearity and a linear time-invariant model, is considered in order to cope with the well-known limitations of the more common small-signal models, i.e. the entity of the variations of the variables around a well-defined steady-state operating point and the incorrect reproduction of the steady-state behavior corresponding to input step variations from the above steady-state operat…

Power Maximization of a PV-Wind HRES via DC-link Voltage Boosting

2009

This paper describes a method for the optimization of a Hybrid Renewable Energy System applied to a low power Photovoltaic-Wind plant. This approach exploits the DC link with a voltage higher than the correspondent value of the batteries, thanks to a suitable DC/DC converter. The goodness of the methodology is firstly proved by means of a novel graphical technique and then verified through numerical simulations. The results are discussed and show that, adopting the proposed technique, a significant increase of the generated power and of the annual energy produced can be achieved.

A Temperature Dependent Non-Linear Inductor Model for a DC/DC Boost Converter

2018

This paper is focused on the use of non-linear inductors in DC/DC switching converters, as well as their behaviour due to changes in current and temperature. The model of an inductor is set up on the basis of experimental data, which are automatically acquired by a virtual instrument; from those data, a polynomial curve describing the inductance variations is obtained. The analysis of the converter, performed by including the proposed model, is validated by experimental tests.

Characterization of inductors in partial saturation for SMPS applications

2017

The exploitation of partially saturated inductors in Switching Mode Power Supply (SMPS) is a key strategy for reducing the size of SMPS and increasing their power density [1]. However an accurate characterization and modellization of each inductor is needed for a correct design and control of the SMPS [2]. Most of inductors' datasheets only indicate the nominal inductance at low current. Anyway, when the inductor is subjected to a higher current, the value of the inductance is lessened. Moreover, inductance meters often actuate their measurements at no or moderate DC bias. In this work we describe the realization of an automated test bench (Fig. 1) for characterizing an inductor under varia…

Design and control of an innovative electronic load for the photovoltaic module characterization

2016

The paper proposes a new electronic load setup for a fast, low-cost and standard-compliant characterization of a photovoltaic module. The approach is based on the use of a DC-DC converter, exploiting its ability to emulate a resistor. In particular, a Buck-Boost converter topology is employed. The model is implemented in the Simulink/SimPower System environment. A commercial PV Conergy E215P photovoltaic module is used in order to evaluate the performances of the proposed electronic load and to validate the proposed approach.

A New Model for Sigma-Delta Modulator Oriented to Digitally Controlled DC/DC Converter

2007

Recent research activities have shown the feasibility and advantages of using digital controller ICs specifically developed for high-frequency switching converters, highlighting a challenging future trend in Switched-mode power supplies (SMPS) applications. Up to a few years ago, the application of digital control for SMPS was impractical due to the high cost and low performance of DSP and microcontroller systems, even if the advantages that digital controllers offer were well known, such as immunity to analog component variations and ability to implement sophisticated control schemes and system diagnostics. Digital controller ICs potentially offer other advantages from the integrated desig…

Power management of a battery/supercapacitor system for E-mobility applications

2019

Hybrid Energy Storage Systems (HESS) have been very popular in recent years in different applications, from electric vehicles (EVs) to smart grids and renewable energies, due to the growing need to accumulate electricity. The concept of hybridization arises from the requirement of both high energy and specific power. The battery/supercapacitor (SC) system offers great advantages in a DC bus, giving the opportunity to provide high amounts of power to the loads. In this paper, a system composed of two bidirectional DC-DC converters, one connected to a battery pack and one to a stack of supercapacitors, is presented for a DC bus in electrical mobility (E-Mobility) applications. The proposed co…

A Model of DC-DC Converter with Switched-Capacitor Structure for Electric Vehicle Applications

2022

In this paper, a DC-DC converter with an innovative topology for automotive applications is proposed. The goal of the presented power converter is the electrical storage system management of an electric vehicle (EV). The presented converter is specifically compliant with a 400 V battery, which represents the high-voltage primary source of the system. This topology is also able to act as a bidirectional power converter, so that in this case, the output section is an active stage, which is able to provide power as, for example, in the case of a low-voltage battery or a supercapacitor. The proposed topology can behave either in step-down or in step-up mode, presenting in both cases a high gain…