A Novel Interactive Power Electronics Seminar(iPES)Developed at the Swiss Federal Institute of Technology(ETH)Zurich

Uwe Drofenik,Johann W. Kolar 전력전자학회 2002 JOURNAL OF POWER ELECTRONICS Vol.2 No.4

This paper introduces the Interactive Power Electronics Seminar - iPES - a new software package for teaching of fundamentals of power electronic circuits and systems iPES is constituted by HTML text with Java applets for interactive animation, circuit design and simulation and visualization of electromagnetic fields and thermal issues in power electronics. It does comprise an easy-to-use self-explaining graphical user interface The software does need Just a standard web-browser, i.e no installations are required iFES can be accessed Via the World Wide Web or from a CD-ROM in a stand-alone PC by students and professionals Due to the underlying software technology IPES IS very flexible and could be used for on-line learning and could easily be integrated into an e-learning platform<br/> The aim of this paper is to give an introduction to the iPES-project and to show the different areas covered. The e-learning software is available at no costs at www mes.ethz.ch in English, German, Japanese, Korean, Chinese and Spanish. The project is still under development and the web page is updated m about 4 weeks intervals.

A Comparison of Separated and Combined Winding Concepts for Bearingless Centrifugal Pumps

Klaus Ragg,Thomas Nussbaumer,Johann W. Kolar 전력전자학회 2009 JOURNAL OF POWER ELECTRONICS Vol.9 No.2

Bearingless centrifugal pump systems are employed in the semiconductor, pharmaceutical and medical industries due to their facility for pumping high purity fluids without particle contamination. Two types of forces have to be generated by the stator units, namely bearing forces for achieving magnetic levitation, and drive forces for producing the needed pump torque. The generation of these forces requires bearing and drive windings, which can be realized as separate bearing and drive coils or as identical, combined coils on the stator claws. In this paper, a detailed comparison between these two winding concepts is undertaken, whereby the copper losses, the power electronics losses, and the achievable pump output pressure are evaluated for both concepts. For each criterion a ratio of improvement is calculated analytically which allows evaluation of the performance of the two winding concepts for any given pump operating point and design. Finally, also practical features such as control complexity, cabling effort and manufacturability are discussed and measurements on prototype systems are carried out to validate the considerations.

Comparison of 2- and 3-level Active Filters with Enhanced Bridge-Leg Loss Distribution

Thiago B. Soeiro,Mario Schweizer,Jorgen Linner,Per Ranstad,Johann W. Kolar 전력전자학회 2011 ICPE(ISPE)논문집 Vol.2011 No.5

In this paper an efficiency comparison between 3-phase shunt active filters derived from the 2-level VSC, the 3-level NPC, Active NPC (A-NPC) and the T-type VSC is presented. In order to address the loss distribution issue of the 3-level topologies, while keeping the efficiency of the system high, a space vector modulation scheme incorporating a special clamping of the phase is proposed. It is shown that 3-level active filters can have their losses well distributed over the chip dies, leading to only a small difference in their operating temperatures. Additionally, a semiconductor area based comparison is used to further evaluate the studied active filter systems. Finally, experimental results obtained with a 12kVAr/48㎑ 3-level NPC based shunt active filter employing custom SiC power modules are presented in order to demonstrate the performance and feasibility of this solution.

Comparison of Electrostatic Precipitator Power Supplies with Low Effects on the Mains

Thiago B. Soeiro,Thomas Friedli,Jorgen Linner,Per Ranstad,Johann W. Kolar 전력전자학회 2011 ICPE(ISPE)논문집 Vol.2011 No.5

In this article, the distortions caused by the power supplies employed in Electrostatic Precipitators (ESP) are investigated, and means for improving the line power quality are proposed. Multi-pulse and PWM rectifier topologies and other concepts including hybrid systems and active filters are evaluated in order to identify suitable systems for ESP applications. A comparison of the studied systems rated to 60 ㎾ and fully designed employing commercial components is shown. The ESP systems efficiency, power density, current harmonic THD, among others features are used for the assessment. The loss calculations are extended to a variable chip area to allow a fair comparison between the studied systems. Finally, the VIENNA 6-switches rectifier and active filter concepts are chosen and experimental analyses are carried out, verifying the performance and feasibility of the proposed systems.

Switching Transient Shaping by Application of a Magnetically Coupled PCB Damping Layer

Michael Hartmann,Andreas Musing,Johann W. Kolar 전력전자학회 2009 JOURNAL OF POWER ELECTRONICS Vol.9 No.2

An increasing number of power electronic applications require high power density. Therefore, the switching frequency and switching speed have to be raised considerably. However, the very fast switching transients induce a strong voltageand current ringing. In this work, a novel damping concept is introduced where the parasitic wiring inductances are advantageously magnetically coupled with a damping layer for attenuating these unwanted oscillations. The proposed damping layer can be implemented using standard materials and printed circuit board manufacturing processes. The system behavior is analyzed in detail and design guidelines for a damping layer with optimized RC termination network are given. The effectiveness of the introduced layer is determined by layout parasitics which are calculated by application of the Partial Element Equivalent Circuit (PEEC) simulation method. Finally, simulations and measurements on a laboratory prototype demonstrate the good performance of the proposed damping approach.

Switching Transient Shaping of RF Power MOSFETs for a 2.5 ㎒, Three-Phase PFC

Michael HARTMANN,Andreas MUSING,Johann W. KOLAR 전력전자학회 2007 ICPE(ISPE)논문집 Vol.- No.-

To increase the power density of active rectifiers, the switching frequency and switching-speed have to be raised considerably. However, the very fast switching transients induce a strong voltage and current ringing. In this paper, a novel magnetically coupled damping layer is introduced for attenuating these unwanted oscillations. The proposed damping layer can be implemented using standard materials and printed circuit board manufacturing processes. The system behavior is analyzed in detail and design guidelines are given. The effectiveness of the introduced layer is determined by layout parasitics, which are calculated with the Partial Element Equivalent Circuit method and compared to impedance measurements. The performance of the damping layer is demonstrated by simulations and verified via measurements on a laboratory prototype.

New 40kV / 300kVA Quasi-2-Level Operated 5-Level Flying Capacitor SiC “Super-Switch” IPM

Piotr Czyz,Panteleimon Papamanolis,Thomas Guillod,Florian Krismer,Johann W. Kolar 전력전자학회 2019 ICPE(ISPE)논문집 Vol.2019 No.5

Emerging applications, e.g., traction systems and utility scale renewable energy systems, demand for Medium Voltage (MV) power electronic switches with blocking capabilities above 20kV, which cannot be provided with today’s 10kV or 15kV SiC power semiconductors. Therefore, this work investigates different concepts for the realization of a MV halfbridge, i.e., a series connection of 10kV SiC MOSFETs, a JFET Super Cascode arrangement, and Modular Multilevel Converter (MMCs) and Flying Capacitor Converter (FCCs) topologies. The FCC topology features several advantages such as reduced switching losses, reduced chip area, lower dv/dt of the switching transitions, and robust voltage balancing. Moreover, the volume of the flying capacitors can be reduced with Quasi-2-Level (Q2L) operation of the half-bridge, where the intermediate voltage levels are only used during very short time intervals, i.e., during the switching transitions. This paper analyzes the design, the switching behavior, and the voltage balancing of the Q2L-FCC bridge-leg and confirms its suitability as a versatile MV switch. Finally, the integration of a complete bridge-leg, including gate drivers, isolated cooling interfaces, measurements, and Q2L control into a 300kVA / 40kV SiC Super-Switch Intelligent Power Module (SiC-SS-IPM) is presented.

Advanced Cooling Concepts for Ultra-High-Speed Machines

A. Tuysuz,M. Steichen,C. Zwyssig,Johann W. Kolar 전력전자학회 2015 ICPE(ISPE)논문집 Vol.2015 No.6

High-speed electrical machines are gaining an increasing attention as they enable higher power densities in several applications such as micro-machining spindles and turbo compressors. This brings along an important challenge in thermal management due to the higher loss densities in the machine. Therefore, a careful thermal analysis is required along with the electromagnetic and mechanical analysis during the design phase of the machines. In this paper, five different forced cooling options for a slotless-type ultra-high-speed permanent-magnet machine are compared. Fast and sufficiently accurate thermal models are derived for analyzing these cooling concepts such that the cooling system design could be integrated in the machine optimization procedure, which would not be feasible when using computationally very intensive methods such as 3-D Finite-Element-Method (FEM) or Computational-Fluid-Dynamics (CFD). Measurements are carried out on the stator of an off-the-shelf 1 kW, 280 000 r/min machine to experimentally compare different cooling methods and to show the validity of the thermal models. A simplified case study shows that the power density can be more than doubled by the selection of a proper cooling system.

22kW EV Battery Charger Allowing Full Power Delivery in 3-Phase as well as 1-Phase Operation

Panteleimon Papamanolis,Florian Krismer,Johann W. Kolar 전력전자학회 2019 ICPE(ISPE)논문집 Vol.2019 No.5

A new universal front-end PFC rectifier topology of a battery charger for Electric Vehicles (EVs) is proposed, which allows fast charging at rated and/or full power level in case of 1-phase (USA) as well as 3-phase (Europe) mains supply. For a conventional 3-phase PFC rectifier, only 1/3 of the rated power would be available in case of 1-phase operation. The new topology is based on a two-level six-switch (2LB6) 3-phase PFC rectifier, which is extended with a diode bridge-leg and additional windings of the Common-Mode (CM) chokes of the EMI filter. The focus of the paper is on the analysis of the generated CM and Differential Mode (DM) EMI noise for both operating modes, i.e., 1-phase and 3-phase operation, resulting in guidelines for EMI filter design. The suggested topology modifications are also applied to a three-level T-type (Vienna) PFC rectifier structure. The theoretical considerations are verified with simulations. Finally, a 22kW prototype of the new universal PFC rectifier is designed using ƞ-ρ Pareto optimization, targeting an efficiency of 98.4 %, a power density of 6.8 kW/dm³, i.e., a volume of 3.24ddm³, and an EMI filter that ensures compliance with the CISPR class B EMI standard. Compared to a volume-optimized design of a conventional 3-phase topology of same power rating and efficiency, but limited 1-phase power transfer capability, the additional volume required for the proposed extension is less than 0.5dm3 (15%) and therefore clearly justified considering the enabled universal applicability of the converter system.

A Novel Interactive Power Electronics Seminar (iPES) Developed at the Swiss Federal Institute of Technology (ETH) Zurich

Drofenik, Uwe,Kolar, Johann W. The Korean Institute of Power Electronics 2002 JOURNAL OF POWER ELECTRONICS Vol.2 No.4

This paper introduces the Interactive Power Electronics Seminar - iPES - a new software package for teaching of fundamentals of power electronic circuits and systems. iPES is constituted by HTML text with Java applets for interactive animation, circuit design and simulation and visualization of electromagnetic fields and thermal issues in power electronics. It does comprise an easy-to-use self-explaining graphical user interface. The software does need just a standard web-browser, i.e. no installations are required. iPES can be accessed via the World Wide Web or from a CD-ROM in a stand-alone PC by students and professionals. Due to the underlying software technology iPES is very flexible and could be used for on-line learning and could easily be integrated into an e-learning platform. The aim of this paper Is to give an introduction to the iPES-project and to show the different areas covered. The e- learning software is available at no costs at $\underline{www.ipes.ethz.ch}$ in English, German, Japanese, Korean, Chinese and Spanish. The project is still under development and the web page is updated in about 4 weeks intervals.