1,721,117 research outputs found
Ferrule-top micromachined devices: A universal platform for optomechanical sensing
Full text linkIannuzzi, D. [Promotor
Applications of Fiber-top Technology for Material Property Characterization at Nanoscale
Full text linkIannuzzi, D. [Promotor
Divide et Impera: Multi-lockin instrument for surface force measurements and applications to Casimir force experiments
Full text linkGriessen, R.P. [Promotor]Iannuzzi, D. [Copromotor
Hunting for Chameleons, a Possible Candidate for Dark Energy
Full text linkIannuzzi, D. [Promotor]Mulders, P.J.G. [Promotor
Spectroscopy at the nanometer scale: Towards nanoscale chemical and physical surface characterization
Full text linkIannuzzi, D. [Promotor]Ariese, F. [Copromotor]Mank, A.J.G. [Copromotor
Ultrafast charging station for electrical vehicles: Dynamic modelling, design and control strategy
No full textThe paper deals with mathematical modelling and the control system for UltraFast Charging Stations (UFCS) based on DC micro-grid concept and Energy Storage System Integration to feed new Electrical Vehicles (EVs) at 800V DC in order to reach the EVs power requirement for charge-time less than 10 min. The UFCS integrates a battery energy storage system (BESS) to reduce the peak power of AC main grid, decoupling the dynamics of the DC charging station from the AC grid by means of its dedicated control system. Designing procedure and Control Strategy, based on Load Levelling power management, are dealt with numerical simulation results in Matlab-Simulink software, presented in order to verify UFCS performance and the charging station's dynamics
Power Control Strategy of a Delta-Connected Photovoltaic Cascaded H-Bridge Converter for Low Voltage Distribution Networks in Energy Community
No full textThe paper deals with the power control of a delta connected Cascaded H-Bridge (CHB) converter equipped with photovoltaic (PV) modules. A hierarchical architecture of energy management is proposed: A 'Module level' controller performs a Maximum Power Point Tracking (MPPT) algorithm to achieve the optimal utilization of each PV module; a 'Leg level' controller manages the power flow control within the modules of a single CHB phase leg, and a 'System' level controller manages the active power flow between the three CHB phases and the reactive power generation towards the grid. The active power control is aimed at the compensation of the mismatches between the different PV-powered modules, which may come from partial shadowing phenomena. A power unbalance compensation between cascaded modules is implemented through the Pulse Width Modulation (PWM) algorithm, while the unbalance compensation between the phases is implemented through the phase currents control. To compensate the active power unbalance due to PV module mismatches, the obtained effect is equivalent to the injection of a zero sequence current. A reactive power control has been implemented to perform a power factor (PF) correction, too. A set of numerical simulations validate the effectiveness of the algorithm, which can simultaneously achieve the desired active power generation from all the PV panels and the desired PF control towards the grid
Experimental Validation of a Semi-Two-Stage Traction System Based on the NPC Multi-Source Inverter for Fuel Cell Rail Vehicles
No full textHydrogen trains have been increasingly considered as an alternative to diesel-powered trains on long-range medium-traffic routes, for which electrification lacks economic attractiveness. In fact, very long autonomies can be reached by hydrogen fuel cell plants with a single refueling. In fuel cell systems, a high-power dc/dc converter must be included to boost the voltage of the fuel cell, which can vary significantly from no load to full load condition. In this paper, a semi-two-stage traction system for hydrogen-powered rail vehicles is investigated and tested. The architecture employs an NPC multi-source inverter as main traction converter to provide an additional connection between the fuel cells and the traction motors. With the coordinated control of the two power converters, the boost converter can be partly bypassed during operation, and its peak power rating and round-trip energy losses reduced. Experimental tests on a lab prototype show significant reductions in the peak current and round-trip energy processed by the dc/dc converter, with expected benefits in terms of weight and volume of its passive filters and heatsinks
Semi-Two-Stage Traction System based on the NPC Multisource Inverter for Tram Vehicles with Onboard Supercapacitors
No full textThis paper proposes an innovative semi-two-stage topology for the traction system of trams equipped with supercapacitors, with the aim to downsize the onboard dc/dc converters. The configuration is obtained through a non-conventional connection of a half-bridge chopper and 3L Neutral Point Clamped (NPC) inverter to the dc sources and ac traction motors. By means of a proper modulation strategy, the NPC converter works as a Multi-Source Inverter and can independently control the power absorbed or supplied by the catenary and supercapacitors. Due to limitations in the power-processing domain of the NPC circuit, a chopper must be also included in the traction circuit. However, it processes only a fraction of the total power of the supercapacitors. The proposed solution is compared against a traditional two-stage architecture, where a dc/dc converter processes the entire power of the capacitors and a 2L Voltage Source Inverter drives the traction motors. Extensive numerical analyses testify that the envisioned architecture shows encouraging performance and can yield a significant reduction of the dc/dc converter ratings, losses, volume, and weight
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