Publications by Michail Vasiladiotis

Operation and Control of Single-to-Three-Phase Direct AC/AC Modular Multilevel Converters under Asymmetric Grid Conditions

Alfred Rufer, Nicolas Cherix, Michail Vasiladiotis

Single-to-three-phase direct AC/AC Modular Multilevel Converters have gained a significant interest in the field of railway interties. The use of such an MMC-based structure implies more advanced control techniques as well as design requirements, especiall ...

2015

Single-to-Three-Phase Direct AC/AC Modular Multilevel Converters with Integrated Split Battery Energy Storage for Railway Interties

Alfred Rufer, Nicolas Cherix, Michail Vasiladiotis

This paper presents a global hierarchized control method for railway interties based on the direct singleto-three-phase AC/AC Modular Multilevel Converter with integrated split battery energy storage. The power and voltage decoupling between the converter ...

2015

Impact of Grid Asymmetries on the Operation and Capacitive Energy Storage Design of Modular Multilevel Converters

Alfred Rufer, Nicolas Cherix, Michail Vasiladiotis

The grid-connected modular multilevel converter (MMC) is very likely to operate under asymmetric grid conditions. Such a converter features several unique characteristics, whichmake its analysis different from other types of power converters in similar cas ...

Institute of Electrical and Electronics Engineers2015

Analysis and Control of Modular Multilevel Converters with Integrated Battery Energy Storage

Alfred Rufer, Michail Vasiladiotis

Multilevel Converters and battery energy storage systems (BESS) are key components in present and future medium voltage networks, where an important integration of renewable energy sources takes place. The Modular Multilevel Converter (MMC) offers the capa ...

Ieee-Inst Electrical Electronics Engineers Inc2015

High-Order Vector Control of Grid-Connected Voltage Source Converters with LCL-Filters

Alfred Rufer, Behrooz Bahrani, Michail Vasiladiotis

This paper proposes a vector control strategy for LCL-filter-based grid-connected voltage source converters (VSCs). The proposed control strategy is inherently capable of attenuating the resonance phenomenon of such systems. This is an advantage over the e ...

Institute of Electrical and Electronics Engineers2014

Modular Converter Architecture for Medium Voltage Ultra Fast EV Charging Stations: Dual Half-Bridge-based Isolation Stage

Alfred Rufer, Behrooz Bahrani, Niklaus Burger, Michail Vasiladiotis

The concept of ultra fast charging of Electric Vehicles (EVs) is expected to contribute significantly to their widespread utilization in long-distance travels. Towards this direction, emerging power electronic topologies will be the key components of the d ...

2014

Modular Multilevel Converters with Integrated Split Battery Energy Storage

Michail Vasiladiotis

The electric power grid is undergoing significant changes and updates nowadays, especially on a production and transmission level. Initially, the move towards a distributed generation in contrast to the existing centralized one implies a significant integr ...

EPFL2014

Accurate Capacitor Voltage Ripple Estimation and Current Control Considerations for Grid-Connected Modular Multilevel Converters

Alfred Rufer, Nicolas Cherix, Michail Vasiladiotis

In this paper the analytical solution for the submodule 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 literatu ...

Ieee-Inst Electrical Electronics Engineers Inc2014

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

Alfred Rufer, Michail Vasiladiotis

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 ...

Ieee-Inst Electrical Electronics Engineers Inc2014

Operation of Modular Multilevel Converters Under Grid Asymmetries

Alfred Rufer, Daniel Siemaszko, Nicolas Cherix, Michail Vasiladiotis

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 ...

2013

Balancing Control Actions for Cascaded H-Bridge Converters with Integrated Battery Energy Storage

Alfred Rufer, Michail Vasiladiotis

This paper investigates the ways to handle active power components for control and balancing purposes in three-phase Cascaded H-Bridge converters with embedded battery energy storage systems. The split storage elements are interfaced to the converter modul ...

2013

Sizing of branch inductors parameters in modular multilevel converters: An analytical approach

Alfred Rufer, Nicolas Cherix, Michail Vasiladiotis

One of the key features of Modular Multilevel Converters is the existence of inductors inside the branches that constitute each of their phases. These inductors, which may be coupled or non-coupled, authorize a certain independency in the control of the br ...

2013

Fictive Axis Emulator-based State Feedback Vector Current Control for Single-Phase Voltage Source Converters

Alfred Rufer, Michail Vasiladiotis

This paper presents a vector current control method tailored for single-phase voltage source converters. In order to imitate the behavior of a three-phase system, the Fictive Axis Emulation (FAE) concept is employed. The latter is able to synthesize the ro ...

2013

Modular Converter Architecture for Medium Voltage Ultra Fast EV Charging Stations: Global System Considerations

Alfred Rufer, Antoine Béguin, Michail Vasiladiotis

Electric Vehicles (EVs) are expected to contribute significantly to the reduction of CO2 emissions and other types of pollution within the next years. However, the concept of their ultra fast charging still poses demanding requirements, both in terms of th ...

2012

Toward Ultrafast Charging of Electric Vehicles

Alfred Rufer, Massimiliano Capezzali, Stefano Grioni, Hans Björn Püttgen, Michail Vasiladiotis, Hardi Hõimoja

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 ...

2012

Power interfaces and storage selection for an ultrafast EV charging station

Alfred Rufer, Michail Vasiladiotis, Hardi Hõimoja

The paper is a summary of the research conducted so far on the ultrafast charging issues of electric vehicles with the main emphasis on the infrastructure. In order to estimate the load curve and peaks resulting from high charging rate, simulations are car ...

2012

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

Alfred Rufer, Nicolas Cherix, Michail Vasiladiotis

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 ...

2012

Functional Modeling and Energetic Macroscopic Representation of Modular Multilevel Converters

Alfred Rufer, Nicolas Cherix, Michail Vasiladiotis

A key feature of Modular Multilevel Converters (MMC) is the continuous and independent nature of the branch currents. Therefore, a decoupled control of the line and partial bus currents is possible, unlike for classical topologies. To this end, several con ...

2012

Power and DC Link Voltage Control Considerations for Indirect AC/AC Modular Multilevel Converters

Alfred Rufer, Stephan Kenzelmann, Nicolas Cherix, Michail Vasiladiotis

A highly interesting application field of the Modular Multilevel Converter is the interconnection of the European three-phase 50 Hz industrial grid with the single-phase 16 2/3 Hz railway supply. Contrary to existing technologies, the utilization of a bulk ...

Ieee2011

A Versatile DC-DC Converter for Energy Collection and Distribution using the Modular Multilevel Converter

Alfred Rufer, Stephan Kenzelmann, Michail Vasiladiotis, Drazen Dujic

The drawbacks of conventional Modular Multilevel Converters (MMC) are described in terms of short-circuits. The configuration of MMC-transformer-MMC proves to handle short-circuits at the input and output without the need for additional DC or AC circuit br ...

Ieee2011