Publications by Alfred Rufer | EPFL Graph Search

Chat with Graph Search

Ask any question about EPFL courses, lectures, exercises, research, news, etc. or try the example questions below.

DISCLAIMER: The Graph Chatbot is not programmed to provide explicit or categorical answers to your questions. Rather, it transforms your questions into API requests that are distributed across the various IT services officially administered by EPFL. Its purpose is solely to collect and recommend relevant references to content that you can explore to help you answer your questions.

Considering the need for a reliable and environmentally friendly energy storage solution for addressing renewable energy intermittency issue and following the developments on Isothermal Compressed Air Energy Storage (I-CAES) systems, a new finned piston co ...

A new electrically driven gas booster is described as an alternative to the classical air-driven gas boosters known for their poor energetic efficiency. These boosters are used in small scale Hydrogen storage facilities and in refueling stations for Hydrog ...

In the framework of Isothermal Compressed Air Energy Storage (CAES), a new finned piston compressor has been designed and realized at LEI laboratory in EPFL. This system comprises a series of concentric annuli’s fitting into each other compressing the air ...

Supercapacitors represent one of the newest innovations in the field of electrical energy storage, and will find their place in many applications where energy storage is needed, or can help to the smoothing of strong and short time power solicitations of a distribution network. Other system developments are going on, opening new fields in engineering sciences, based on new possibilities in the field of electrical energy storage. In comparison with classical capacitors, these new components allow a much more

Energy storage systems can be considered today as new means to adapt the variations of the power demand to the given level of power generation. In the context of the use of Renewable Energies or other distributed power generation, they can be used also as additional sources, or as energy buffers in the case of non-schedulable or stochastic generation, like wind- or photovoltaic power. This paper will describe different means of electrical energy storage, including systems where other energy transformations

In addition to the high-capacity storage facilities based on hydropower technologies, electrochemical solutions are today’s candidate for storage for renewable energy sources support. However, sustainability and limited life cycles of batteries are often i ...

Beside the high-capacity storage facilities based on hydro-power technologies, electrochemical solutions are the today's candidate for storage for renewable energy sources. However, limited life-cycles and sustainability of batteries are often inhibiting f ...

Multistage hydraulic systems and methods for converting the potential energy of a pressurized gas, particularly air, into mechanical work operating in motor, and for producing compressed gas from the mechanical work of the rotating shaft (A1.1 ) when rotat ...

This paper presents an alternative way for the current regulation of single-phase voltage-source dc-ac converters in direct-quadrature (dq) synchronous reference frames. In a dq reference frame, ac (time varying) quantities appear as dc (time invariant) on ...

A system dedicated to energy storage is presented. It allows energy storage from photovoltaic panels to a compressed air accumulator. This accumulator is controlled to enable compression and expansion modes under Maximum Efficiency Point Tracking (MEPT). A ...

This paper proposes a multivariable digital control design methodology for the voltage regulation of an islanded single distributed generation (DG) unit microgrid and its dedicated load. The controller design methodology is based on a family of spectral Mu ...

This paper presents an alternative way for controlling the current of single-phase voltage source dc-ac inverters in a dq synchronous reference frame. In a dq reference frame, ac (time varying) quantities appear as dc (time invariant) quantities allowing t ...

The paper is devoted to the problems arising from the ultrafast (≤ 10 min) charging of an electric vehicle (EV). An ultrafast charging station (UFCS) must provide high power output with minimal influence on the electricity transmission system, which can on ...

This article introduces the energetic macroscopic representation (EMR) as approach for the dynamic nonlinear modeling of a reciprocating air compressor. EMR has been introduced recently for research development in complex electromechanical systems. It is b ...

The Modular Multilevel Converter is very likely to operate in a grid-connected mode under asymmetric conditions. Such a converter features several unique characteristics, which make its analysis different from other types of power converters in similar cas ...

Large Physics experimentation as in particle accelerators or in nuclear fusion is often characterised by a strong and modulated power demand, incompatible with the power availability of the grid. Therefore, large facilities for short-term energy storage ha ...

This paper presents hybrid energy storage systems based on hydro-pneumatics and Supercapacitors with high potentials regarding life cycle and impacts on environment. These so called “Batteries with Oil-hydraulics and Pneumatics (BOP)” systems exploit the h ...

Single-phase active rectifiers exhibit an inherent strong second-order current harmonic on their DC-link. The latter is often undesirable from a load point of view and is therefore chosen to be eliminated. A common method is the use of a resonant passive L ...

The analytical solution for the sub-module voltage ripple equations of a Modular Multilevel Converter (MMC) is derived, based on the knowledge of the external voltage/current magnitudes and enhancing a concept previously presented in literature. In order t ...

Alfred Rufer

Chat with Graph Search

Design, modeling and experimental validation of a novel finned reciprocating compressor for Isothermal Compressed Air Energy Storage applications

Increasing the Energy Efficiency of Gas Boosters for Hydrogen Storage and for Refueling Stations

Thermo-Electric Analogy Method for Computing Transient Heat Transfer in a New Reciprocating Finned Piston Compressor

Key Developments for Supercapacitive Energy Storage: Power Electronic Converters, Systems and Control

Solutions for storage of electrical energy

A Hybrid Energy Storage System Based on Compressed Air and Super Capacitors With Maximum Efficiency Point Tracking (MEPT)

PWM-control of multi-level voltage-source inverters

Hybrid Energy Storage Systems based on Compressed Air and Supercapacitors with Maximum Efficiency Point Tracking

Multistage hydraulic gas compression/expansion systems and methods

Vector Control of Single-Phase Voltage-Source Converters Based on Fictive-Axis Emulation

Direct Connection of Supercapacitors to Photovoltaic Panels With On–Off Maximum Power Point Tracking

A Multivariable Design Methodology for Voltage Control of a Single-DG-Unit Microgrid

Vector Control of Single-Phase Voltage Source Converters based on Fictive Axis Emulation

Toward Ultrafast Charging of Electric Vehicles

Modeling of a Reciprocating Air Compressor using Energetic Macroscopic Representation

Operation of Modular Multilevel Converters Under Grid Asymmetries

A novel 60 MW Pulsed Power System based on Capacitive Energy Storage for Particle Accelerators

Principle of Hybrid Energy Storage Systems based on Hydro-pneumatics and Supercapacitors for Distributed Generation and Renewable Energy Sources Support

Dynamic Analysis and State Feedback Voltage Control of Single-Phase Active Rectifiers with DC-Link Resonant Filters

Accurate Voltage Ripple Estimation and Decoupled Current Control for Modular Multilevel Converters