References of "Hadji-Minaglou, Jean-Régis 50001922"
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See detailExperimental studies on the development of a solar hybrid module with an aluminum microchannel evaporator
Rullof, Johannes UL; Lambers, Klaus Jürgen; Dick, Christian et al

in Proceedings of 2016 International Energy and Sustainability Conference (IESC 2016) (2016)

In recent years, the possibility to combine photovoltaics (PV) and solar thermal collectors into one hybrid module (PVT-module) has been increasingly investigated. PVT-modules produce thermal and ... [more ▼]

In recent years, the possibility to combine photovoltaics (PV) and solar thermal collectors into one hybrid module (PVT-module) has been increasingly investigated. PVT-modules produce thermal and electrical energy at the same time. As the efficiency of a photovoltaic module decreases with temperature, the temperature of the heat transfer media is often limited to about 30 °C and the PVT-module is combined with a heat pump, which increases the temperature on the “warm side”. This paper deals with a PVT-module, which combines a microchannel based evaporator of a CO2 (R744) heat pump with a PV panel (PVT-direct). The PVT-direct overall system is reduced to the refrigerant circuit due to the direct refrigerant expansion in the PVT-module. A conventional PVT heat pump system has an additional glycol-water circuit. Since a pump and an additional heat exchanger for the secondary cycle were omitted, the system has increased efficiency. Due to lower module temperatures, the increase of the photovoltaic efficiency is a further advantage of the PVT-direct-module. To prove the feasibility of the PVT-direct heat pump system, the Cologne Institute for Renewable Energy (CIRE) is developing and modeling a test facility for this purpose within the research project “PVT-direkt”. Furthermore, a functional PVT-direct-module with a microchannel based evaporator was designed and built. Much importance has been given to experimental studies under laboratory conditions in order to investigate (1) the adjustment of the functionality and layout of the PVT-direct-module for characterizing the joining of brazed joints in aluminum microchannel evaporators and (2) the influence of the backside aluminum plate of the PVT-direct-module regarding leakage currents and parasitic capacitances. The overall results obtained in these experimental studies are analyzed in this paper. [less ▲]

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See detailA new Single-phase PLL based on the input voltage magnitude estimation
Kobou Ngani, Patrick UL; Hadji-Minaglou, Jean-Régis UL; Marso, Michel UL et al

Scientific Conference (2015, December 17)

Many automatic control applications such as wide scale power grid management and local power conditioning rely on the fast and accurate detection of the voltage signal phase and amplitude. These ... [more ▼]

Many automatic control applications such as wide scale power grid management and local power conditioning rely on the fast and accurate detection of the voltage signal phase and amplitude. These information are almost all the time given by the Phase –locked Loop (PLL) systems and can be single-phase or three-phase and have many different structures. Many single-phase PLLs core structure are based on the regulation to zero of the voltage direct component in the rotating d-q frame obtained through the Park-transform. Their accuracy and dynamic rely on how quick and accurate the second voltage’s component in the static α-β frame is estimated. This paper presents a new single-phase PLL structure, also based on the same core structure as described before, but implementing a novel voltage β-component generation. A brief review of some single-phase PLLs is made, then the proposed novel PLL structure is detailed and its performance is compared with that of the other PLL’s taking into consideration the following signal disturbances: amplitude variations, phase step variation and frequency fluctuations as well as harmonic distortion. [less ▲]

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See detailPhase-error correction by single-phase phase-locked loops based on transfer delay
Kobou Ngani, Patrick UL; Hadji-Minaglou, Jean-Régis UL; Marso, Michel UL et al

in Journal of Electrical & Electronic Systems (2015, November 04)

Comparative studies of different single-phase phase-locked loops (PLL) algorithms have been made. They show that the PLL based on sample delay (dPLL), presents the lowest computational load and is as ... [more ▼]

Comparative studies of different single-phase phase-locked loops (PLL) algorithms have been made. They show that the PLL based on sample delay (dPLL), presents the lowest computational load and is as robust as the three-phase synchronous reference frame PLL dqPLL by input signal amplitude and phase variations. Its weakness appears when the input signal frequency differs from its rated frequency: It depicts a steady error on the calculated signal phase-angle. After a brief review of the dqPLL which constitutes debase structure of the dPLL, the following work will present three methods that improve the phase detection accuracy of dPLL. It is shown that the modifications brought in the original structure do not influence the robustness and stability of the algorithm but reduce the phase angle offset error by input signal frequency variation. This is corroborated by tests including not only the fundamental input voltage disturbance like amplitude, phase and frequency variation but also harmonic voltage distortion. [less ▲]

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See detailDistributed Harmonic Compensation for Power Quality in Smart Grids
Kobou Ngani, Patrick UL; Hadji-Minaglou, Jean-Régis UL; Marso, Michel UL et al

in Cahier Scientifique - Revue Technique Luxembourgeoise (2014)

It is now well known that the quality of electric power is a key factor for the electricity service. It defines how good the characteristics (amplitude and frequency) of the supplied power meet the rated ... [more ▼]

It is now well known that the quality of electric power is a key factor for the electricity service. It defines how good the characteristics (amplitude and frequency) of the supplied power meet the rated ones. Voltage dip (or sag) and swell, short and long interruptions, voltage spike, under and over voltage, harmonic distortion, voltage unbalance are the common power quality problems. Among these last, the harmonics issue is getting more and more important over the last decades and this trend will surely continue its race. This is essentially due to the widespread use of electronic components in electric equipment: it changes the nature of the electric loads from linear to non-linear and makes them, on the one hand, responsible for the harmonics generation in the power grid but very sensitive to the power quality problems on the other hand. [less ▲]

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See detailDecentralized Power Supply for Small and Medium User Facilities
Hadji-Minaglou, Jean-Régis UL; Hoben, Ralf UL; Peters, Bernhard UL

Patent (2014)

The world-wide energy consumption has almost doubled since 1980 despite efforts towards energy saving and efficiency. This trend is supposed to continue for the decades to come so that major energy crises ... [more ▼]

The world-wide energy consumption has almost doubled since 1980 despite efforts towards energy saving and efficiency. This trend is supposed to continue for the decades to come so that major energy crises with electricity cuts and shortage of petrol or gas are anticipated. Furthermore, an ever increasing consumption of fossil fuels significantly contributes to further emissions of greenhouse gases and consequently to global warming in conjunction with catastrophic climate changes. These impacts are reduced to a large extent through utilisation of renewable energy sources for and within decentralised user facilities. The present invention relates to a method of communicating operation modes between a user facility control unit at a user facility and a utility grid control unit of a utility grid. In particular, it relates to a decentralised method of communicating operation modes between a user facility control unit at a user facility with renewable energy supply and a utility grid control unit of a utility grid. [less ▲]

Detailed reference viewed: 100 (2 UL)
See detailMethods and Means for Harmonics Compensation in Electrical Power Generation
Hadji-Minaglou, Jean-Régis UL

Patent (2014)

Feeding more and more multiple non-linear and unsymmetrical power consumers (TV, Computers etc…) cause serious disturbances for the grid quality in terms of voltage harmonics and distortion power in ... [more ▼]

Feeding more and more multiple non-linear and unsymmetrical power consumers (TV, Computers etc…) cause serious disturbances for the grid quality in terms of voltage harmonics and distortion power in particular in decentralised low power supplies like solar photovoltaic (PV) in households. The use of inverter-fed power devices with modern high speed micro-controllers and an intelligent management of the different powers to be generated can help improving the power quality under any operating conditions. The invention provides a compensation algorithm implemented in a micro-controller combining the use of Finite Impulse Response (FIR) filters to extract the different harmonics from the original voltage signal and applies a Phase Locked Loop (PLL) to every extracted harmonic signal, which is finally compensated via a Proportional-Integral (PI) controller. All the PI controllers outputs are superposed in the final voltage source in such a way that they don’t conflict with each other, leading to a stable voltage source generation with a total harmonic distortion (THD) smaller than the limit of 8% requested by the global European power quality norm EN50160. The active harmonics compensator is able to compensate individually the strongest harmonics due to the feedback effect on the voltage source of any kind of non-linear load at partial-load as well as overload operation. The compensation can be implemented on a self-sufficient single voltage generating power source running in stand-alone or grid-tied. It can also be shared and distributed on multiple voltage source inverters (VSI) of different powers connected on a utility grid. That allows an optimisation of the power production of each device, in particular supplied by variable renewable energy sources (solar PV, wind), taking into consideration its capacity currently available. [less ▲]

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See detailStructured Analysis of Arbitrary Island Grids
Jostock, Markus UL; Sachau, Jürgen UL; Hadji-Minaglou, Jean-Régis UL et al

Scientific Conference (2013, October 08)

This paper recapitulates an analytic control model for arbitrary island grids and presents findings on the dynamic behaviour of purely inverter driven island grids. Pole zero plots of different grid ... [more ▼]

This paper recapitulates an analytic control model for arbitrary island grids and presents findings on the dynamic behaviour of purely inverter driven island grids. Pole zero plots of different grid structures are presented and the influence of several inverter parameters on the grid stability is analysed. Findings show that for improved grid stability the inverter’s time constants should also relate to their rated power. Further it is shown how P-Q rotation in the droop control can improve the integration density of renewable power sources in the distribution grid. [less ▲]

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See detailAn Efficient Nonlinear Model-Predictive Eco-Cruise Control for Electric Vehicles
Schwickart, Tim Klemens UL; Voos, Holger UL; Hadji-Minaglou, Jean-Régis UL et al

in 11th IEEE International Conference on Industrial Informatics, Bochum, Germany, 29-31 July 2013 (2013, July)

A nonlinear problem formulation of an energy-saving model-predictive eco-cruise controller for electric vehicles is presented. With regard to the intended application in real-world tests, the model has to ... [more ▼]

A nonlinear problem formulation of an energy-saving model-predictive eco-cruise controller for electric vehicles is presented. With regard to the intended application in real-world tests, the model has to include the specific properties of a serial electric vehicle such as energy-recovery and a discontinuous accelerator input giving rise to a binary control variable. These specific features and the nonlinearity of the system dynamics make it a challenging task to formulate the optimisation problem in a way that allows a fast computation in real-time application. The challenges are addressed by using a model of the vehicle dynamics that is formulated in terms of the vehicle position instead of time and by considering the kinetic energy instead of the velocity. Furthermore, various constraints on the input and state variables are introduced for a realistic representation of the vehicle characteristics. A special focus is put on the treatment of a binary input variable in the optimisation. Here, in order to avoid a mixed-integer formulation of the problem, a continuous variable is introduced which is forced to take only discrete values by a penalty term. Finally, first simulation results underline the feasibility of this control approach. [less ▲]

Detailed reference viewed: 311 (39 UL)