Valorisez vos réalisations phares sur People@HES-SO Plus d'infos
PEOPLE@HES-SO – Annuaire et Répertoire des compétences
PEOPLE@HES-SO – Annuaire et Répertoire des compétences

PEOPLE@HES-SO
Annuaire et Répertoire des compétences

Aide
language
  • fr
  • en
  • de
  • fr
  • en
  • de
  • SWITCH edu-ID
  • Administration
« Retour
Siemaszko Daniel

Siemaszko Daniel

Professeur HES associé

Compétences principales

Électronique de puissance

Convertisseurs modulaires

Stockage énergétique intermédaire

Microréseaux hybrides AC/DC

  • Contact

  • Publications

  • Conférences

Contrat principal

Professeur HES associé

Bureau: B57a

Haute Ecole d'Ingénierie et de Gestion du Canton de Vaud
Route de Cheseaux 1, 1400 Yverdon-les-Bains, CH
HEIG-VD
Institut
IE - Institut des énergies
Aucune donnée à afficher pour cette section

2024

Continuous time simulation and system-level model of a MVDC distribution grid including SST and MMC-based AFE
Article scientifique ArODES

Daniel Siemaszko, Mauro Carpita

Electronics,  2024, 13, 11, 2193

Lien vers la publication

Résumé:

Medium-voltage DC (MVDC) technology has gained increasing attention in recent years. Power electronics devices dominate these grids. Accurate simulation of such a grid, with detailed models of switching semiconductors, can quickly became very time-consuming, according to the number of connected devices to be simulated. A simulation approach based on interactions on a continuous time model can be very interesting, especially for developing a system-level control model of such a modern MVDC distribution grid. The aim of this paper is to present all the steps required for obtaining a continuous time modelling of a +/−10 kV MVDC grid case study, including a solid-state transformer (SST)- and modular multilevel converter (MMC)-based active front end (AFE). An additional aim of this paper is to supply educational content about the use of the continuous time simulation approach, thanks to a detailed description of the various devices modelled into the presented MVDC grid. The results of a certain number of simulation scenarios are eventually presented.

2019

Small-scale modular multilevel converter for multi-terminal DC networks applications :
Chapitre de livre ArODES
system control validation

Elie Talon Louokdom, Serge Gavin, Daniel Siemaszko, Frédéric Biya-Motto, Bernard Essimbi Zobo, Mario Marchesoni, Mauro Carpita

Dans Grandi, Gabriele, Ruderman, Alex, Multilevel converters : analysis, modulation, topologies, and applications  (pp. 487-505). 2019,  Basel, Beijing, Wuhan, Barcelona, Belgrade : MDPI

Lien vers la publication

Résumé:

This paper presents the design and implementation of a digital control system for modular multilevel converters (MMC) and its use in a 5 kW small-scale prototype. To achieve higher system control reliability and multi-functionality, the proposed architecture has been built with an effective split of the control tasks between a master controller and six slave controllers, one for each of the six arms of the converter. The MMC prototype has been used for testing both converter and system-level controls in a reduced-scale laboratory set up of a Multi-Terminal DC transmission network (MTDC). The whole control has been tested to validate the proposed control strategies. The tests performed at system level allowed exploration of the advantages of using an MMC in a MTDC system.

2018

Small-scale modular multilevel converter for multi-terminal DC networks applications :
Article scientifique ArODES
system control validation

Elie Talon Louokdom, Serge Gavin, Daniel Siemaszko, Frédéric Biya-Motto, Bernard Essimbi Zobo, Mario Marchesoni, Mauro Carpita

Energies,  2018, 11, 7, 1690

Lien vers la publication

Résumé:

This paper presents the design and implementation of a digital control system for modular multilevel converters (MMC) and its use in a 5 kW small-scale prototype. To achieve higher system control reliability and multi-functionality, the proposed architecture has been built with an effective split of the control tasks between a master controller and six slave controllers, one for each of the six arms of the converter. The MMC prototype has been used for testing both converter and system-level controls in a reduced-scale laboratory set up of a Multi-Terminal DC transmission network (MTDC). The whole control has been tested to validate the proposed control strategies. The tests performed at system level allowed exploration of the advantages of using an MMC in a MTDC system.

2015

Fast sorting method for balancing capacitor voltages in modular multilevel converters
Article scientifique ArODES

Daniel Siemaszko

IEEE Transactions on Power Electronics,  30, 1, 463-470

Lien vers la publication

Résumé:

The modular multilevel converter (MMC) is attracting more and more interest in high-power and high-voltage applications. Highly redundant, each arm of the converter is made of a large number of identical submodules with inner storage capability allowing to reach very high voltage without dc-link capacitor. The control of such a converter represents a challenge when it comes to the implementation of an MMC with a large number of submodules, namely in distributing the control tasks and handling the communicated values in-between controllers and submodules. This paper presents the details of an innovative submodule selection method for the submodule capacitor's voltage balancing within one arm of an MMC. “The Tortoise and the Hare” sorting method shows very fast response, high reliability, and its implementation suits a large number of implemented submodules as for high-voltage dc applications. The proposed submodule capacitor's balancing method is validated on a three-phase 10-kVA prototype with five submodules per arm.

2011

Open-loop control of modular multilevel converters using estimation of stored energy
Article scientifique ArODES

Lennart Ängquist, Antonios Antonopoulos, Daniel Siemaszko, Kalle Ilves, Michail Vasiladiotis, Hans-Peter Nee

IEEE Transactions on Industry Applications,  47, 6, 2516-2524

Lien vers la publication

Résumé:

The internal control of a modular multilevel converter aims to equalize and stabilize the submodule capacitor voltages independent of the loading conditions. It has been shown that a submodule selection mechanism, included in the modulator, can provide voltage sharing inside the converter arm. Several procedures for controlling the total stored energy in each converter arm exist. A new approach is described in this paper. It is based on estimation of the stored energy in the arms by combining the converter electromotive force reference, the measured alternating output current, and the known direct voltage. No feedback controllers are used. Experimental verification on a three-phase 10 kVA prototype is presented along with the description of the new procedure.

Single-Phase Resonant $LC$ Circuit Using a Bank of Self-Switched Capacitors
Article scientifique ArODES

Daniel Siemaszko, Christian Rod, Alfred C. Rufer

IEEE Transactions on Industrial Electronics,  58, 9, 4175-4184

Lien vers la publication

Résumé:

This paper presents a preliminary work on the feeding of an ac dipole using a resonant circuit with a varying resonant frequency. A single-phase LC oscillator containing a variable capacitor is fed by a wideband amplifier or a voltage source inverter. For this purpose, a bank of switched capacitors of different values are connected to the main circuit through bidirectional switches. In order to allow zero-current and zero-voltage switchings, the devices are implemented with close-control driver circuits, allowing self-switching based on local polarity measurements. An innovative controller for maintaining the current in an oscillator and a regressive method for measuring alternating current with a limited number of samples are proposed and validated by experiment.

2009

Description and efficiency comparison of two 25 kVA DC/AC isolation modules
Article scientifique ArODES

Daniel Siemaszko, Frédéric Zurkinden, Lukas Fleischli, Irma Villar, Yales R. De Novaes, Alfred C. Rufer

EPE Journal,  19, 4, 17-24

Lien vers la publication

Résumé:

In the frame of the European project UNIFLEX-PM, two AC/AC converter topologies have been studied and implemented. Both converters, rated for 25 kVA, are isolated by a medium frequency power transformer. The first topology is based on a dual active bridge containing two additional voltage source inverters for the connection of both DC links to the interfaced grids. The second topology is based on a cycloconverter for the connection of the secondary side of the transformer to the grid without a DC link capacitor. Both topologies have an identical primary side so the efficiency study is focussed on the chain link from one DC link to a 25 kW output load. Experimental efficiencies are compared to theoretical expectations. Due to soft-switching operation in the dual active-bridge, the cycloconverter based solution shows a lower efficiency than in the symmetrical topology.

2025

Experimental insights into the MW Range dual active bridge with silicon carbide devices
Conférence ArODES

Stefanie Heinig, Daniel Siemaszko, Remo Baumann, Noemi Hubatka, Martin Klaeusler, Raul Ruiz, Ralph Burkart

International Power Electronics Conference (IPEC-Himeji 2022 - ECCE Asia)

Lien vers la conférence

Résumé:

Alongside the resonant topology of the Power Electronics Transformer, the Dual Active Bridge is one potential topology candidate for various LVDC and MVDC applications. For its study purpose, a 0.55 MW converter unit was built featuring the latest inhouse developed Medium Frequency Transformer operated by SiC LinPak semi-conductor devices. Main interest focusses on maximizing its efficiency in various operating points. The converter is experimentally demonstrated with two cells operated in back-to-back configuration.

2024

Enabling MVDC PV collection grids with modular solid state transformers
Conférence ArODES

Daniel Siemaszko, Marko Mogorovic

Proceedings of the 6th International Conference on DC Microgrids (ICDCM)

Lien vers la conférence

Résumé:

Solar energy is typically collected through AC grids because of strong reliability and availability of standard solutions. The introduction of Solid State Transformers may not only allow reducing footprint and losses, but also implement peak shaving capabilities and the injection to MVDC grids directly. This work proposes an innovative PV energy collecting strategy with modular isolated DC/DC converters.

2023

System modelling and reliability study of the tri-port SST featuring energy storage and distributed redundancy for data centers
Conférence ArODES

Daniel Siemaszko, Marko Mogorovic

Proceedings of 25th European Conference on Power Electronics and Applications (EPE'23 ECCE Europe)

Lien vers la conférence

Résumé:

DC powered Data Centers may profit from the proposed Tri-Port SST with UPS for linking MVDC distribution and LVDC bus to IT loads. The solution shows benefits in terms of reliability and efficiency and reduces the number of conversion stages. This work gives demonstrative figures and system level modelling details.

MVDC distribution concept for green data centers :
Conférence ArODES
achieving the sustainability roadmap with highest efficiency

Daniel Siemaszko, Stefanie Heinig, Chunming Yuan, Javier Iglesias, Marko Mogorovic

Proceedings of PCIM Europe 2023

Lien vers la conférence

Résumé:

This paper proposes a DC electric energy distribution scheme for data centers. Most state-of-the-art data centers use AC distribution at all voltage levels, from MV at the feeder substation down to the 380 VAC indoor distribution level for direct connection of IT racks. This paper provides a DC distribution scheme that is equivalent to state-of-the-art AC distribution systems in terms of specific and very stringent availability and reliability requirements. It features significant benefits in terms of efficiency and controllability and focuses specifically on the integration of solar power, fuel cells, and battery-based UPS, with the MV Solid State Transformer (“SST”) as the enabling technology. The proposed DC distribution scheme provides flexible solution for future green data centers committed to the 2030 Sustainability Roadmap – 100% supply from renewable energy sources at any hour.

2017

Use of data-mining for non-invasive signature recognition in micro-grids :
Conférence ArODES
A preliminary approach applied to residential areas with PV converters

Daniel Siemaszko, Michel Speiser

Proceedings of 19th European Conference on Power Electronics and Applications (EPE'17 ECCE Europe)

Lien vers la conférence

Résumé:

The future of distribution networks tends more and more to include computational power, embedded intelligence and smart metering on the high voltage level as well as the low voltage micro-grids. Several hardware solutions were developed to implement the so-called smart grids with measurement devices delivering data about the state of networks on various levels. This work introduces the use of a specific electric signature based on harmonic response of power converters in order to be able to get information in a non-invasive manner. A simulated residential grid with several loads and PV converters has been run real-time with 1 μs sampled data, for being able to retrieve information through data mining methods.

Use of modular multilevel converter in multi-terminal DC transmission network :
Conférence ArODES
reduced scale set-up and experimental results

Elie Talon Louokdom, Daniel Siemaszko, Serge Gavin, David Leu, Patrick Favre-Perrod, Mauro Carpita

Proceedings of 2017 19th European Conference on power Electronics and Applications (EPE'17 ECCE Europe), 11-14 September 2017, Warsaw, Poland

Lien vers la conférence

Résumé:

In the frame of a collaboration project within Swiss Competence Centre for Energy Research, a Multi Terminal DC pilot has been implemented. For the interaction with the medium voltage AC grid, a Modular Multilevel Converter has been designed for its features in low harmonic content, scalability, and flexibility. The control of converters in the MTDC network implements a non-dead band voltage control. The Energy buffering of the MMC converter will allow the converter to sustain either AC or DC grids. The operation of the MMC converter in an MTDC network containing three converter is verified experimentally in a reduced-scale pilot.

2016

Implementation and experimental set-up of a modular multilevel converter in a multi terminal DC/AC transmission network
Conférence ArODES

Daniel Siemaszko, Elie Talon Louokdom, Hervé Parisod, Jonathan Braun, Serge Gavin, Loïc Eggenschwiler, Patrick Favre-Perrod, Mauro Carpita

Proceedings of 2016 18th European Conference on Power Electronics and Applications (EPE'16 ECCE Europe), 5-9 September 2016, Karlsruhe, Germany

Lien vers la conférence

Résumé:

In this paper the realization of a Multi Terminal DC pilot is presented. For the interaction with the medium voltage AC grid, a Modular Multilevel Converter has been designed for its features in low harmonic content, scalability, and flexibility. The Energy buffering of the converter will allow the converter to sustain either AC or DC grids. The operation of the converter is simulated together with the first experimental results of the implementation.

Design and implementation of a multi-dsp based digital control system architecture for modular multilevel converters
Conférence ArODES

Elie Talon Louokdom, Serge Gavin, Daniel Siemaszko, Frédéric Biya-Motto, Bernard Essimbi Zobo, Mauro Carpita

Proceedings of 2016 IEEE International Power Electronics and Motion Control Conference (PEMC), 25-28 September 2016, Varna, Bulgaria

Lien vers la conférence

Résumé:

This paper presents the design and implementation of a digital control system for modular multilevel converters, based on digital signal processors. To achieve higher system control reliability and multi-functionality, the proposed architecture has been built with an effective split of the control tasks involved between a master controller and six slave controllers, one for each of the six arms of the converter. The master controller handles energy flow within the converter and user communication using Ethernet and universal serial bus. Each slave controller handles capacitors voltages balancing within the arm. Intercommunication between the different boards is achieved mainly through optical fiber and inter-integrated circuit bus. Experiments have been carried out to verify the effectiveness of this architecture.

2015

Conception of a modular multilevel converter in a multi-terminal DC/AC transmission network
Conférence ArODES

Daniel Siemaszko, Mauro Carpita, Patrick Favre-Perrod

Proceedings of 2015 17th European Conference on Power Electronics and Applications (EPE'15 ECCE-Europe), 8-10 September 2015, Geneva, Switzerland

Lien vers la conférence

Résumé:

In the frame of a collaboration project within Swiss Competence Centre for Energy Research in the Future Swiss Electrical Infrastructure section, a Multi Terminal DC pilot has been implemented for studying the interaction between an HVDC and a high voltage AC grid. For the interaction with the medium voltage AC grid, a Modular Multilevel Converter is being designed for its features in low harmonic content, scalability, and flexibility. The energy buffering of the converter will allow the converter to sustain either AC or DC grids. The operation of the converter is described in details and simulated.

Double-Frame current control with a multivariable PI controller and power compensation for weak unbalanced networks
Conférence ArODES

Daniel Siemaszko, Alfred Rufer

Proceedings of CAS - CERN Accelerator School : Power Converters

Lien vers la conférence

Résumé:

The handling of weak networks with asymmetric loads and disturbances im- plies the accurate handling of the second-harmonic component that appears in an unbalanced network. This paper proposes a classic vector control approach using a PI-based controller with superior decoupling capabilities for operation in weak networks with unbalanced phase voltages. A synchronization method for weak unbalanced networks is detailed, with dedicated dimensioning rules. The use of a double-frame controller allows a current symmetry or controlled imbalance to be forced for compensation of power oscillations by controlling the negative current sequence. This paper also serves as a useful reminder of the proper way to cancel the inherent coupling effect due to the transformation to the synchronous rotating reference frame, and of basic considerations of the relationship between switching frequency and control bandwidth.

2014

Modular resonant converter for 25kV-8A power supply: design, implementation and real time simulation
Conférence ArODES

Daniel Siemaszko, Louis de Mallac, Serge Pittet, Davide Aguglia

Proceedings of 16th European Conference on Power Electronics and Applications 2014

Lien vers la conférence

Résumé:

This paper describes the design of a 300kW modular resonant power converter for an application in particle accelerators. The aim of the power supply is to provide a so-called RF cavity with 25kV DC voltage and a current up to 8A. Modular approach is chosen for redundancy and availability. Each module is composed of a resonant tank with a step-up MF transformer with its secondary windings put is series for reaching higher voltages. Full gain is ensured in the full operation frequency range considering component value inaccuracies and ageing of capacitors. The design of the resonant tank is detailed with its dimensioning and integration issues. Hardware in the loop validation of two control methods is done on one 100kW module to prepare experimental validation of a single module before implementing the full system.

Design of a modular resonant converter for 25kV-8A DC power supply of RF cavities
Conférence ArODES

Daniel Siemaszko, Serge Pittet, Davide Aguglia, Louis de Mallac

Proceedings of the 2014 International Power Electronics Conference (IPEC-Hiroshima 2014 - ECCE ASIA)

Lien vers la conférence

Résumé:

This paper describes the design of an LCC resonant tank that is to be used in a 300kW modular power converter for an application in particle accelerators. The aim of the power supply is to provide a so-called RF cavity with 25kV DC and a current up to 8A. Modular approach is chosen for redundancy and availability. Each module is composed of a resonant tank with a step-up Medium Frequency Transformer with its secondary windings put is series. Full gain is ensured in the full operation frequency range considering component value inaccuracies and ageing of capacitors. The paper focusses on the design of the resonant tank and its implementation in a 100kW power module prototype.

2013

Operation of modular multilevel converters under grid asymmetries
Conférence ArODES

Michail Vasiladiotis, Nicolas Cherix, Daniel Siemaszko, Alfred Rufer

Proceedings of 39th Annual Conference of the IEEE Industrial Electronics Society (IECON 2013)

Lien vers la conférence

Résumé:

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 cases. The existence of three independent capacitive phase legs rather than a common DC-link capacitor requires special attention, in terms of stability and component dimensioning. This paper investigates the impact of unbalanced grid conditions on the operation of the Modular Multilevel Converter. The expressions for the branch energy variation are derived assuming that the grid-related quantities can be modeled by means of symmetrical components. Moreover, the effect of circulating current control for capacitive storage reduction as well as DC-link oscillation elimination is also studied. Finally, a control system is proposed and simulation results verify its discrete-time implementation.

Double frame control and power compensation for power converters connected to weak networks with disturbances
Conférence ArODES

Daniel Siemaszko

Proceedings of 15th European Conference on Power Electronics and Applications (EPE)

Lien vers la conférence

Résumé:

CERN is studying the implementation of high power active front ends, implying the operation of a voltage source inverters connected to a grid that can be considered as weak when compared to the converter nominal power. Proper synchronisation is a key point for current control stability. The handling of networks with asymmetric disturbances implies the accurate handling of the second harmonic component appearing under unbalanced networks by the proper decoupling of the positive and negative sequence of the network voltages and currents. The use of a double frame controller allow the full control of phase current symmetry or the compensation instantaneous active power oscillation.

Power compensation approach and double frame control for grid connected converters
Conférence ArODES

Daniel Siemaszko, Alfred, C. Rufer

Proceedings of IEEE 10th International Conference on Power Electronics and Drive Systems (PEDS)

Lien vers la conférence

Résumé:

The handling of weak networks with asymmetric disturbances implies the accurate handling of the second harmonic component appearing under unbalanced networks. This paper proposes a two-step approach using classic vector control for operating the current controller from the network disturbance. First, both voltage and current must be described in the positive and negative sequence with a proper decoupling. The use of a double frame controller for forcing current balance proves to drastically reduce the second harmonic component in the DC-link voltage. As a second step, a current reference computing method is proposed for fully compensating power oscillations on the DC side that is applicable for phase voltage dips up to 50%.

2012

Grid synchronization of power converters to weak unbalanced networks with disturbances
Conférence ArODES

Daniel Siemaszko

Proceedings of the 2012 Electrical Systems for Aircraft, Railway and Ship Propulsion

Lien vers la conférence

Résumé:

In the context of the multiplication of micro-grids or delocalized energy sources, one must face more and more disturbances coming especially from weaker isolated grids. The control of the active rectifier unit connecting the grid must be designed not only for surviving a voltage dip with some ride-through methods, but for actually controlling the currents during a network unbalance. This purpose is served with the accurate synchronization to the grid considering all its perturbations and allowing advanced dynamics for any type of disturbances. This paper presents the use of a performant PLL coming from renewable sources power converters oriented for drive applications.

Optimal automatic tuning of PID controllers applied to grid converters
Conférence ArODES

Konstantinos G. Papadopoulos, Daniel Siemaszko, Nikolaos I. Margaris

Proceedings of the 2012 Electrical Systems for Aircraft, Railway and Ship Propulsion

Lien vers la conférence

Résumé:

A systematic automatic tuning method for PID-type controllers in SISO systems is proposed. The method is inspired from the Magnitude Optimum design criterion and considers 1) the existence of a poor process model and 2) access to the output of the process and not to its states, as it frequently happens in many industry applications. For applying the method, an open-loop experiment of the process is carried out which serves for initializing the algorithm. The method proceeds by identifying on line the dominant time constants of the plant and the `parasitic' one of the closed-loop system. The potential of the proposed method is justified on the vector control loop of a grid power converter via simulation results.

Positive and negative sequence control for power converters under weak unbalanced networks
Conférence ArODES

Daniel Siemaszko

Proceedings of the 2012 Electrical Systems for Aircraft, Railway and Ship Propulsion

Lien vers la conférence

Résumé:

In the application field of AC/DC converters connected to utility networks, the DC-link voltage controller is generally too slow to compensate the second harmonic component caused by the unbalance of the phase voltages. Assuming the accurate description of the unbalance in the network voltages, namely by the accurate decomposition in the positive and negative sequence synchronous reference frame, the generated currents are also decoupled into two parts and separately controlled. For the proper cancellation of the oscillation in the power taken from the network, the unbalance in the voltages is taken into account in the calculation of the four current references. Results show that the DC-link voltage show no second harmonic component and is able to operate with weak networks under voltage unbalance.

2011

Impact of modularity and redundancy in optimising the reliability of power systems that include a large number of power converters
Conférence ArODES

Daniel Siemaszko, Serge Pittet

Microelectronics Reliability

Lien vers la conférence

Résumé:

CERN is working on a new particle accelerator that will require a very large number of power converters. In that view, the reliability of the whole powering will be a major issue. The use of a redundancy and modularity may help increasing the overall machine availability. However, the reliability of the redundancy system must be high enough to add a significant improvement when compared to simple module systems. This paper suggests a comparative study of several modular and redundant configurations for optimising power converters reliability and draws some conclusion from what has been achieved in the LHC previous experience.

Reliability models applied to a system of power converters in particle accelerators
Conférence ArODES

Daniel Siemaszko, Michel Speiser, Serge Pittet

Proceedings of the 2011 14th European Conference on Power Electronics and Applications

Lien vers la conférence

Résumé:

Several reliability models are studied when applied to a power system containing a large number of power converters. A methodology is proposed and illustrated in the case study of a novel linear particle accelerator designed for reaching high energies. The proposed methods result in the prediction of both reliability and availability of the considered system for optimisation purposes.

Failure tolerant operation and trimming principle in the CLIC main linac
Conférence ArODES

Daniel Siemaszko, Serge Pittet

Proceedings of the 2011 14th European Conference on Power Electronics and Applications

Lien vers la conférence

Résumé:

A powering strategy for a high number of magnets disposed in a radiated and confined area is presented for a particle accelerator application. One power converter supplies the main current in series connected magnets. Then, for adjusting each current individually, small active trimmers are implemented together which each magnet. The trimmers are only dissipative, implemented as MOSFETs operated in their linear region and controlled by analog PI controllers. The reliability of the whole powering system is ensured with failure tolerance that complies with beam physics. The steady state operation and dynamic response in case of failures are experimentally studied in a reduced scale prototype.

Klystron modulator technology challenges for the Compact Linear Collider (CLIC)
Conférence ArODES

D. Aguglia, C.A. Martins, M. Cerqueira Bastos, D. Nisbet, Daniel Siemaszko, E. Sklavounou, P. Viarouge

Proceedings of the 2011 IEEE Pulsed Power Conference

Lien vers la conférence

Résumé:

This paper presents the research and development challenges foreseen for the klystron modulators design for a new accelerator complex, the Compact Linear Collider (CLIC). This huge electron-positron accelerator needs roughly 300MW of average power for feeding the 1638 required klystron modulators. The main challenges for designing theses new pulsed klystron modulators are described. Considering the state of the art in several domain such as converters topologies, voltage measurements precision, pulse-to-pulse reproducibility, AC power quality issues, efficiency maximization, accelerator reliability & availability, this paper illustrates the most challenging future developments directions and the need for an international and coordinated R&D program.

2010

Inner control of modular multilevel converters :
Conférence ArODES
an approach using open-loop estimation of stored energy

Lennart Ängquist, Antonios Antonopoulos, Daniel Siemaszko, Kalle Ilves, Michail Vasiladiotis, Hans-Peter Nee

Proceedings of the 2010 International Power Electronics Conference - ECCE ASIA -

Lien vers la conférence

Résumé:

The inner control of a Modular Multilevel Converter (M2C) must be designed so that the submodule capacitor voltages are equalized and stable independent of the loading conditions. It has been shown that a submodule selection mechanism, included in the modulator, can provide voltage sharing inside the converter arm. Several procedures for controlling the total stored energy in each converter arm exist. A new approach is described in this paper. It is based on estimation of the arm energy from measured ac output current and dc voltage. No feedback controllers are used. Experimental verification on a 3-phase 10 kVA prototype is presented along with the description of the new procedure.

Evaluation of control and modulation methods for modular multilevel converters
Conférence ArODES

Daniel Siemaszko, Antonios Antonopoulos, Kalle Ilves, Michail Vasiladiotis, Lennart Ängquist, Hans-Peter Nee

Proceedings of the 2010 International Power Electronics Conference - ECCE ASIA -

Lien vers la conférence

Résumé:

The modular multilevel converter is a promising converter technology for various high-voltage high-power applications. Despite the apparent simplicity of the circuit, the inherent dynamics of the converter and the balancing of the sub-module capacitor voltages impose high requirements on the control system, which can be implemented in quite different ways. To illustrate this, and to provide a guidance for future research on the subject, this paper presents an evaluation of four different control and modulation methods. The investigation is based on experiments on a down-scaled 10 kVA converter having 10 submodules per phase leg. The main items to be investigated are dynamics within the sub-modules, arm voltages and circulating currents. It is found that the suggested open-loop control method provides the fastest arm-voltage response and that the balancing approach based on a sorting algorithm is substantially faster and less complicated to implement than the method using a dedicated voltage controller for each sub-module.

2009

Active self-switching methods for emerging monolithic bidirectional switches applied to diode-less converters
Conférence ArODES

Daniel Siemaszko, Alfred C. Rufer

Proceedings of the 2009 13th European Conference on Power Electronics and Applications

Lien vers la conférence

Résumé:

This paper presents a recently introduced switching principle for emerging monolithic bidirectional devices. Based on the hypothesis that those switches may overcome conventional diode type solutions in power converters, an active self-switching process becomes compulsory. Its principle relies on the measurement of both voltage and current polarity, in order to allow a natural switching as commonly used in matrix conversion. A self-switching method, implemented close to the switch, allows the detection of both short-circuits and open circuits. The accuracy of the presented system is experimented and validated in a 1kVA buck converter where the free-wheeling path is performed by a synthesised diode. The results that are discussed in this paper open a new perspective by introducing the principle of a so-called bidirectional diode as well as the commutation of sources of a similar nature.

Controlled resonant circuit with commutated capacitors using self-switching power devices
Conférence ArODES

Daniel Siemaszko, Christian Rod, Alfred C. Rufer

Proceedings of the 2009 IEEE International Symposium on Industrial Electronics

Lien vers la conférence

Résumé:

This paper presents a preliminary work on a resonant circuit, also called AC-dipole. The resonance frequency of the circuit is changed by the mean of a variable capacitor connecting an inductor. For this purpose, a bank of switched capacitors of different values are connected to the main circuit through bidirectional switches. An experimental validation of the principle is performed on a resonant circuit containing two precharged capacitors. The switches are implemented with close-control driver circuits, allowing zero-voltage and zero-current switching by the mean of both current and voltage polarity measurement. In order to maintain the magnitude of oscillations in the circuit, a regulating system is proposed with its simulation.

2007

New self-switching mechanisms for active bidirectional switches
Conférence ArODES

Daniel Siemaszko, Philippe Barrade, Yales Romulo De Novaes, Alfred C. Rufer

Proceedings of the 2007 European Conference on Power Electronics and Applications

Lien vers la conférence

Résumé:

The self-switching principle is a synthesis of synchronous type switching and switch inner protection mechanisms. Both switch ON and switch OFF are performed on the base of current and voltage measurement across the switch. Applied to an active bidirectional device, it may give complete autonomy to the switch. On the basis of those principles, the synthesis of an autonomous bidirectional free-wheeling path for an AC/AC buck converter is implemented with active switches. This paper introduces the current/voltage state representation in order to illustrate the experimental switching mechanisms. As a further application, the automatic triac is synthesized for a bipolar AC/DC half-bridge converter.

The active self-controlled free-wheeling management principle applied to reverse recovery losses reduction
Conférence ArODES

Daniel Siemaszko, Philippe Barrade, Alfred C. Rufer

Proceedings of the 2007 Power Conversion Conference

Lien vers la conférence

Résumé:

Several works suggest the imminent appearance of bidirectional active devices. The promised performances go in the direction of a reverse recovery effects reduction and efficiency improvement. Our purpose is the study of an active management for switches that cannot be spontaneous in commutation as a diode. Based on zero-crossing detection and protection circuits, new mechanisms are introduced. As an application, a free-wheeling path is performed using a bidirectional active switch. The principles are verified in two basic converters. For experimental results, a bidirectional switch is implemented using a combination of MOSFETs in direct and reverse conduction.

Réalisations

Médias et communication
Nous contacter
Suivez la HES-SO
linkedin instagram facebook twitter youtube rss
univ-unita.eu www.eua.be swissuniversities.ch
Mentions légales
© 2021 - HES-SO.

HES-SO Rectorat