D. Boroyevich

Survey on High-Temperature Packaging Materials for SiC-Based Power Electronics Modules

High temperature SiC devices need the materials for device packages also capable of working at higher temperature than those for Si devices. This paper presents a selection of materials that are potentially suitable for use in high temperature package assembly, including die attach, substrate, interconnections, encapsulation, case, heat spreader and heat sink. The temperature under consideration is up to 250degC, corresponding to the need of many applications, including automobiles and aircraft.

Reduction of high-frequency conduction losses using a planar litz structure

A new trend in power converters is to design planar magnetic components that aim for low profile. However, at high frequencies, ac losses induced in the planar inductor and transformer windings become significant due to the skin and proximity effects. A planar litz conductor can be constructed by dividing the wide planar conductor lengthwise into multiple strands and weaving these strands in much the same manner as one would use to construct a conventional round litz wire conductor. Each strand is then equally subjected to the magnetic fields in the winding window, thereby equalizing the flux linkage and improving the current distribution. Three-dimensional finite-element modeling was performed for simple models. The simulation results showed that the planar litz conductor can result in lower ac resistance than a solid conductor over a specific frequency range. The performance of the planar litz winding was also verified with measurements on two experimental prototypes.

A new distributed digital controller for the next generation of power electronics building blocks

The need for low-cost, high-reliability, modular, easy to use and maintain power electronics systems is fuelling the drive for standardized power electronics building blocks (PEBBs). Increased power density, user-friendly design, multifunctionality and increased reliability are the major issues that are being investigated. This paper proposes a new distributed digital control architecture for medium and high power PEBBs. The proposed architecture features high level of flexibility, modularity and paves the way towards future plug and play power converter systems.

High-Density Nanocrystalline Core Transformer for High-Power High-Frequency Resonant Converter

A high-density transformer using nanocrystalline core is developed for a 30 kW, 200 kHz resonant converter. Loss models are established for nanocrystalline cores through experimental characterization. The important parasitic models are also developed considering litz wire effects. Following a minimum size design procedure, several transformers with both nanocrystalline and ferrite cores are designed and prototyped. While all transformers meet the converter performance requirement during testing, using nanocrystalline core can achieve a significantly higher power density even at 200 kHz.

Comparison of prospective topologies for aircraft autotransformer-rectifier units

This paper explores the feasibility of employing 18-pulse autotransformer rectifier units (ATRUs) for more electric aircrafts, thus expanding the usage of these converters onto variable, high frequency applications. Particularly, the paper presents a detailed comparison of three 18-pulse ATRUs, based on input ac harmonic current distortion, output voltage regulation, common mode voltage, impact of impedance mismatch between rectifier paths and impact of input voltage harmonic distortion. The comparison is carried out for the full range of the input line frequency from 400 to 800 Hz. Key analyses and results obtained with Saber simulations are presented for validation of the presented work.

A High-Power-Density Converter

This article presents the development and experimental performance of a 10-kW high-power-density three-phase ac-dc-ac converter. The converter consists of a Vienna-type rectifier front end and a two-level voltage source inverter (VSΓ)To reduce the switching loss and achieve a high operating junction temperature, the SiC JFET and SiC Schottky diode are used. Design considerations for the phase-leg units, gate drivers, integrated input filter-combining electromagnetic interference (EMI) and boost inductor stages-and the system protection are described in full detail. Experiments are carried out under different operating conditions, and the results obtained verify the performance and feasibility of the proposed converter system.

Open modular power electronics building blocks for utility power system controller applications

This paper explores using modular power electronics building blocks (PEBBs) in building power electronics based controllers for utility systems applications. The analysis of the existing and proposed controller functions identifies three basic PEBB converter functions for power system controllers: bidirectional AC switch, bidirectional AC/DC voltage source converter, and DC/DC converter. An open system hierarchical architecture is proposed to standardize the analysis, characterization and construction of applications based on PEBBs. Case study results on PEBB based STATCOM are presented. This work will allow us to focus on optimizing only limited number of standard PEBB converters to reduce the system cost and improve reliability.

Experimental evaluation of IGBTs for characterizing and modeling conducted EMI emission in PWM inverters

As a step to achieve the objective of predicting electromagnetic interference (EMI) noise in IGBT PWM inverters, this paper proposes a new and practical EMI noise source modeling method. An equivalent Thevenin source in the frequency-domain, including the voltage source and source impedance, is employed to model the main EMI noise emission source - the IGBT switching. The modeling approach for both the differential mode (DM) and common mode (CM) noise source is studied. The methodology is verified experimentally using a simple, controlled testbed. The important issues on measurement repeatability and data processing are also investigated and discussed.

Definition and acquisition of CM and DM EMI noise for general-purpose adjustable speed motor drives

Separating conducted EMI noise into different modes, common mode (CM) and differential mode (DM), is important to the appropriate application of emission reduction techniques. While the CM/DM separation is well defined and understood for the single-phase or DC system, the same cannot be said for three-phase converter systems, common for general-purpose adjustable speed drives (ASD). Based on the study of CM and DM propagation characteristics of a three-phase diode-front converter, this paper identify different noise modes for different front-diode conducting patterns. The impact on EMI filter components by these noise modes is summarized. Finally, a time-domain based method is proposed to separate and acquire CM and DM noise components for the diode-front three-phase systems. Simulation and experimental verifications are presented.

Power electronics technology: present trends and future developments

The history of special issues of the P ROCEEDINGS OF THE IEEE on subjects concerning power electronics started in August 1967 with the Special Issue on “High Power Semiconductor Devices” (Guest Editors F. E. Gentry and R. A. York) with 26 papers, including one on a power integrated circuit. This was followed in April 1988 with the Special Issue on “Power Electronics” (Guest Editors R. G. Hoft and H. A. Owen) with 17 papers, highlighting many new and exciting applications throughout the whole power range. The Special Issue on “Power Electronics and Motion Control” of August 1994 (Guest Editor B. K. Bose), with 12 papers, reflected very much the topics of the time with the accent on the role of power electronics in drives and their control. We now proudly present you with the new special issue in this field for June 2001. With the appearance of this fourth special issue, composed of 16 papers, we have a chance to look back on a century of power electronics—some retrospection and evaluation may be in order. From its humble beginnings at the start of the 20th century, tied to the technology of mastering the conduction processes in gases and in vacuum, the electronic processing of electrical energy—or power electronics—has come a long way through several generations of technologies. In this process of continuous growth, it has for a long time been clear that the limiting aspect of all these technologies was the electronic switching components. The frequencies of operation and the switch transition times were in such a range that the rest of the circuit elements—capacitors, inductors, transformers—had near ideal behavior, especially during initial system conception. The focus was on getting better and better power switches. Every increase in switch performance led to a corresponding improvement in power electronics technology. In response to every major power semiconductor technology development, power electronics really took off. In particular, bipolar power transistors, thyristors, power MOSFETs, GTOs, IGBTs, and IGCTs really delivered their promises. Power electronics stretched from microwatts to approaching the gigawatt range, while frequencies now cover from power frequencies to the megahertz range. The