UPCommons - E-prints UPC Universitat Politècnica de Catalunya
E-prints UPC cobreix dues finalitats: per una banda, és el dipòsit institucional de la UPC que recull els articles de revista, les comunicacions de congrés i els reports de recerca generats en les activitats de recerca del personal docent i investigador de la universitat; per l'altra, és una eina que permet accelerar la producció científica, allotjant versions de documents prèvies a la publicació en una revista o a les actes d’un congrés.
Implementation of grid-connected to/from off-grid transference for micro-grid inverters - Heredero Peris, Daniel; Chillón Antón, Cristian; Pages Gimenez, Marc; Gross, Gabriel Igor; Montesinos Miracle, Daniel
This paper presents the transfer of a microgrid
converter from/to on-grid to/from off-grid when the converter
is working in two different modes. In the first transfer presented
method, the converter operates as a Current Source Inverter
(CSI) when on-grid and as a Voltage Source Inverter (VSI) when
off-grid. In the second transfer method, the converter is operated
as a VSI both, when operated on-grid and off-grid. The two
methods are implemented successfully in a real platform but the
later offers some advantage.
Induction heating of liquids with an L-LC resonant tank - Quirós Jacobo, Francisco Javier; Martín Segura, Guillermo; Heredero Peris, Daniel; Montesinos Miracle, Daniel
Induction heating (IH) systems are used in many applications because they
present many advantages compared other heating methods like quicker heating or
faster start-up. This paper studies the application of IH systems for liquid heating
using an L-LC resonant tank.
Design, management and comissioning of a utility connected microgrid based on IEC 61850 - Ruiz Alvarez, A.; Colet Subirachs, A.; Gomis Bellmunt, Oriol; Fernández Mola, José María; Alvarez Cuevas, F.; López Mestre, Joaquim; Sudrià Andreu, Antoni
This paper presents an approach to microgrid
automation. The microgrid is composed of three different nodes connected to the public electric grid, which are hardware
emulated with back-to-back converters. The microgrid is a flexible and weather independent test bed for testing different
control algorithms. The intelligence of the automation system is split in three hierarchical layers: the RMU layer, the iNode
layer and the iSocket layer. Communications among iNode and iSockets are according IEC 61850 standard.
The aims of the project is to comission a set of technologies and acquire experience in microgrid automation, IEC 61850
communications and power control algorithms in DER systems.
Control of a utility connected microgrid - Colet Subirachs, A.; Ruiz Alvarez, A.; Gomis Bellmunt, Oriol; Alvarez Cuevas, F.; Sudrià Andreu, Antoni
This paper describes the control algorithm of a utility connected microgrid, based on independent control of active and reactive power (PQ control) and working in centralized
operation mode. The microgrid under investigation is composed of three configurable units: a generation unit, a storage unit and a load. These units are interfaced with the microgrid through a
Voltage Source Converter (VSC) and are controlled by the nodes of the communication system by means of IEC 61850. A set of
tests have been conducted to evaluate the microgrid behavior.
A sensorless stable V/f control method for a five-phase PMSM - Sala Pérez, Pau; Galcerán Arellano, Samuel; Montesinos Miracle, Daniel
This paper presents a sensorless and stable control method for a five-phase permanent magnet synchronous motor (PMSM). At first, a model of a five-phase PMSM is presented. After that a stability study has been performed by the analysis of the eigenvalues of the state transition matrix of the linearized PMSM model about an operating point. The results show that the machine speed response is unstable for input frequencies below the machine rated frequency. Finally, an open-loop V/f stabilization algorithm which ensures the stability of the system over a wide range of speed is presented.
Modeling and validation of a flywheel energy storage lab-setup - Diaz Gonzalez, Francisco; Sumper, Andreas; Gomis Bellmunt, Oriol; Villafafila Robles, Roberto
This work deals with the modeling, control and experimental validation of a flywheel test bench which is part of IREC’s lab-scale microgrid. The storage device has been
designed as a proof of concept. It is based on a low-speed rotating disk mechanically coupled to a Permanent Magnet Synchronous
Machine. The electrical power is exchanged with the external grid by means of a set of back-to-back power converters. These
power electronics control the speed of the machine, and thus the active power absorbed or injected by the device, and also
regulate the reactive power at the point of common coupling with the external grid. Vector...
Passive and Active Methods of Islanding for PV systems - Skocil, Tomas; Gomis Bellmunt, Oriol; Montesinos Miracle, Daniel; Galcerán Arellano, Samuel; Rull Duran, Joan
This paper presents a review of some techniques for islanding detection, especially by using inverter based DG applications and it also focuses on several islanding detection methods for a single- phase current-control voltage inverter working with a PV system connected into the grid. It is deliberated a single-phase inverter with maximum power of 5 kW. Islanding detection methods are investigated, simulated and evaluated in MATLAB / SIMULINK.
Requirements for EV charge stations with photovoltaic generation and storage - Cairó, Ignasi; Sumper, Andreas
With the increase in electric mobility, public and private charge facilities will be required to provide solutions adjusted to the actual needs and requirements. A new
methodology for dimensioning charge stations for electric vehicles (EVs) is presented in this paper. Such proposal is based on the Markov chains, and uses as output rates, the capabilities of the charge station in providing energy from the sun through
photovoltaic generation, stored energy in local batteries and also as a back-up the power grid. A numerical result is also presented for a better understanding of the process.
Multichannel high-power high-frequency converters for induction heating - Martín Segura, Guillermo; Sala Pérez, Pau; Montesinos Miracle, Daniel; Ferrater Simón, Coia; López Mestre, Joaquim
This paper studies a converter structure based on the connection of basic topologies to form
a multichannel converter for induction heating applications. The aim of using basic topologies
is to provide a reduction of design time, the cost derived from higher volume production, stock
components and installation and maintenance work. First, the aim of the paper is introduced,
afterwards the topology is discussed and then implemented
Grid-connected to/from off-grid transference for micro-grid inverters - Heredero Peris, Daniel; Chillón Antón, Cristian; Pages Gimenez, Marc; Gross, Gabriel; Montesinos Miracle, Daniel
This paper compares two methods for controlling the on-line transference from connected to stand-alone
mode and vice versa in converters for micro-grids. The first proposes a method where the converter
changes from CSI (Current Source Inverter) in grid-connected mode to VSI (Voltage Source Inverter) in
off-grid. In the second method, the inverter always works as a non-ideal voltage source, acting as VSI,
using AC droop control strategy.
Multilevel modular DC/DC converter for regenerative braking using supercapacitors - Massot Campos, Miquel; Montesinos Miracle, Daniel; Bergas Jané, Joan Gabriel; Rufer, Alfred
Regenerative braking is presented in many electric traction applications such as electric and hybrid vehicles, lifts and
railway. The regenerated energy can be stored for future use, increasing the efficiency of the system. This paper outlines the benefits of the MMC (modular multilevel converter) in front of the cascaded or series connection of converters to achieve high voltage from low voltage storage elements such as supercapacitors. The paper compares three different solutions and shows that the MMC can benefit from weight and volume reduction of the output inductance when shifted switching modulation strategy is used. Using this modulation strategy, not only...
Dimensioning electric charging posts for PEV - Cairó, Ignasi; Cruz, Miguel; Sumper, Andreas
This paper represents a new analysis method for the estimation of the required charging infrastructure for the electric vehicles (EV’s). The study is based on a real metropolitan area, taking real data from transport habits, and a prediction of certain degree of penetration of EV’s. To cope with this analysis, is the application of powerful tools, used for example in telecommunication systems such as Markov chains, and applied here into EV’s necessities and charging stations infrastructures. This theory is applied in a real example to provide more insight on how can be applied in real circumstances.
Energy management system of hybrid microgrid with energy storage - Marzband, Mousa; Sumper, Andreas; Chindris, Mircea; Tomoiaga, Bogdan
The economic scheduling of the generation units is playing a significant role in the energy management of the hybrid stand alone microgrid. Energy storage is an increasingly important part of the renewable energy sector because of the need to store power during peak production times for use in off-peak periods. This paper describes an energy
management system (EMS) for an islanded microgrid (MG) comprising wind energy conversion system (WECS),photovoltaic (PV), energy storage (ES) system, and microturbine (MT) for calculating the battery charging price (BCP) factor. To reach this objective, firstly the battery system has been modeled using the presented equations then...