I. Martínez de Alegría

Analysis of the technology currently used in Offshore Wind energy systems

This paper gives an overview to the foundations, the Offshore Wind Turbines (OWTs) and the collection and transmission systems of Offshore Wind Farms (OWFs). Although for some of the components of their Electric Systems (ESs) there are different technical possibilities under consideration, under certain conditions of sea depth and distance from shore there are already tested industrial solutions available. However, the technology is not mature yet and decisions adopted today could condition the future expansion of operating OWFs or the development of the already planned Offshore Wind Power Plants (OWPPs). This paper presents the information gathered from about 93% of the currently operating OWFs. Moreover, OWPPs under construction have also been considered to confirm the conclusions presented and to detect current technological trends.

High power high voltage DC/DC converter for MVDC distribution applications

Smart grids and distributed power will play a big role in the future power grid. In the future many DC grids will coexist with the traditional AC grids. This paper presents an efficient and low cost alternative for unidirectional or asymmetric interconnection of DC grids using MVDC transmission lines using High Frequency Transformers.

Market forecasts, feasibility studies and regulatory framework for offshore wind energy integration

This paper gives an overview of several aspects of Offshore Wind Power (OWP) integration. During last year the wind market has exceed forecasts despite of the global crisis, with the offshore market offering very good numbers. Moreover, some projections presented in the paper show that OWP installed during the next five years will probably overcome European Wind Energy Association (EWEA)s forecasts. Logically, investors of OWP projects demand accurate viability plans, which in turn ask for rigorous cost analysis and revenue forecasts considering the whole life cycle of the installation. However, the electricity price in an open market is expected to show certain volatility in the presence of large amount of Renewable Energy Supplies for Electricity (RESE), which makes governmental supporting schemes essential. The European Commission (EC) has established a new regulatory framework called to play a key role in promoting and sustaining RESE and Member States have specified those support schemes in their National Renewable Energy Action Plans (NREAPs).

FPGA solution for matrix converter double sided space vector modulation algorithm

Matrix Converters (MCs) present several advantages, but yet several barriers must be overcome, such as MC modulation and control technique complexity. This article proposes a multiplatform environment that allows the implementation of the Double Sided Space Vector Modulation (DS-SVM) algorithm in a last-generation Field Programmable Gate Array (FPGA) device. The traditional digital control architecture, based on a SP and some additional devices, is improved by means of a last generation FPGA where the main processor (PowerPC), internal memory, communication interfaces, I/O capabilities and a hardware core that executes the DS-SVM have been connected using on-chip buses. The methodology begins by defining the DS-SVM in a Matlab-Simulink environment. The PowerPC delivers 680 MIPS, but it is not a good candidate to execute the DS-SVM algorithm because it is not possible to achieve the modulation frequency that is necessary for an MC. A new configurable hardware circuit that implements the whole DS-SVM algorithm is proposed. This solution achieves modulation frequencies over 100 kHz. This hardware core is connected to one of the PowerPC buses and the processor can configure it or get feedback information at any time. As the processor is liberated from the very time-consuming DS-SVM computation, it can execute many higher level tasks.

Two-phase liquid cooling for electric vehicle IGBT power module thermal management

The main goal of this work is to show the advantages of two-phase cooling technology for thermal management of high power electronics modules, with a SKIM909GD066 motor inverter as the test device for thermal/fluid analysis. Dissipated power, heat transfer coefficient and fluid temperature are set in a 3-D FEM (Finite Element Method) based thermal model to simulate two-phase cooling of IGBTs at the motor inverter. A comparison of two-phase cooling with single-phase cooling is made to address the advantages of the two-phase solution.