A New Current Control Strategy for Three-Phase Rectifiers

International audienc

Dynamic Behavior of the Doubly Fed Induction Generator During Three-Phase Voltage Dips

International audienceThe use of doubly fed induction generators (DFIGs) in large wind turbines has become quite common over the last few years. These machines provide variable speed and are driven with a power converter which is sized for a small percentage of the turbine-rated power. A drawback of the DFIG is that it is very sensitive to grid disturbances, especially to voltage dips. However, the operation of the machine in these situations has only been studied in the literature by means of simulations. This paper develops a theoretical analysis of the dynamic behavior of the induction machine during three-phase voltage dips. The proposed analysis contributes to understanding the causes of the problem and represents a very useful tool to improve the existing solutions and propose new alternatives. Experimental results are in good agreement with those obtained theoretically and validate the proposed analysis

Power adaptor device for domestic DC microgrids based on commercial MPPT inverters

This paper presents a power adaptor device, referred to as smart panel device, allowing the connection of additional energy sources and storage elements to a domestic photovoltaic (PV) grid-connected system. The adaptor output port is designed to behave as a power source/sink, thus enabling its hot-swap parallel connection to renewable power sources without modifying their maximum power point (MPP). Moreover, the adaptor device features a power characteristic with a single controllable MPP and allows the control of the injected power within the operating range of the dc–ac grid-connected inverter. The work presents the design principles of such device by describing the operation of a sliding- mode controlled quadratic-boost converter. The proper operation of the device is experimentally verified for several scenarios in a small PV-based microgrid system including a fuel-cell stack, a 1-kW three-phase wind turbine, a battery charger–discharger, and commercial grid-connected PV invertersPeer ReviewedPostprint (published version

Power adaptor device for domestic DC microgrids based on commercial MPPT inverters

This paper presents a power adaptor device, referred to as smart panel device, allowing the connection of additional energy sources and storage elements to a domestic photovoltaic (PV) grid-connected system. The adaptor output port is designed to behave as a power source/sink, thus enabling its hot-swap parallel connection to renewable power sources without modifying their maximum power point (MPP). Moreover, the adaptor device features a power characteristic with a single controllable MPP and allows the control of the injected power within the operating range of the dc–ac grid-connected inverter. The work presents the design principles of such device by describing the operation of a sliding- mode controlled quadratic-boost converter. The proper operation of the device is experimentally verified for several scenarios in a small PV-based microgrid system including a fuel-cell stack, a 1-kW three-phase wind turbine, a battery charger–discharger, and commercial grid-connected PV invertersPeer Reviewe

A null space algorithm for mixed finite element approximation of Darcy's equation

SIGLEAvailable from British Library Document Supply Centre-DSC:8715.1804(2001-006) / BLDSC - British Library Document Supply CentreGBUnited Kingdo