Professional Education Seminars

APEC 2004 features 21 professional education seminars with a broad range of topics. The conference committee has worked hard to make sure there is something of interest to all APEC attendees during each of the seminar time periods. As always, APEC seminars offer a practical mix of theory and application for the professional working in power electronics. Unlike other conferences that charge by the seminar, at APEC one low fee gains you access to any and all of the seminars, along with the notes for every seminar. Whether you want to review an important topic area, broaden your understanding of a neighboring discipline, or take advantage of the practical experiences of experts in the field, the APEC 2004 seminars are a must for every conference attendee.

Please note that the room assignments are tentative and subject to change. Please check with the registration desk at the conference for the latest information.

PROFESSIONAL EDUCATION SEMINARS

F. Marshall Miles
Belfuse Power, Oklahoma City, OK
South Ballroom A

This seminar presents a broad overview of the power industry for the non-technical professional. It is intended to provide a foundational understanding of the power industry necessary for today's project manager, commodity manager, sales person or anyone involved in the business of power conversion. While some technical concepts are presented, they are done so with the non-technical audience in mind.

The first part of the seminar is an introduction to power technology. This provides an acquaintance with types of power supplies, power supply functionality, and concepts of volts and amps. The history of power technology is briefly reviewed. With this basis, the discussion moves on to powering an electronic system. First, the historical requirements are reviewed. The newer requirements, such the proliferation of the number of voltages in a system and dealing with low voltages at high currents, are presented. This section concludes with an introduction to various power system architectures.

The third part of the seminar tries to help make sense of the bewildering array of power options. For example, power supplies are available as standards, modified standards and full custom. And in the power world, standard has its own meaning. The discussion will then move to comparing specifications, which never seem to lend themselves to an apples-to-apples comparison. This leads to interesting challenges in product compatibility and assuring product from more than one supplier are interchangeable enough for your application. This section concludes with a discussion of cost versus performance versus flexibility.

The fourth and last section of the seminar is an introduction to the power business, starting with the economics of the power supply industry. Sourcing strategies are presented. The cost, time and risk associated with a power supply development project are presented. The seminar concludes with a presentation of some industry resources that can be of help.

Marty Brown
Sierra Energy Management Systems, LLC, Phoenix, AZ
Avalon Room

This seminar is aimed at the novice switching power supply designer who seeks a further intuitive understanding of the design of switching power supplies. Information will be conveyed on the intuitive level with very few equations.

The content will include: how does a switching power supply differ from a linear power supply, descriptions of how basic switching power supplies work, what are topologies and how does one know which is the right one for the application, designing or selecting some of the key components, What are losses and how does one identify them, feedback compensation, and descriptions of the new developments within the power field.

The anticipated outcome of attending this seminar will be a greater appreciation of the operation of switching power supplies and a basic knowledge of their design. A list of literature will show the attendee how to get more information involving the design and understanding of switching power supplies.

Seminar Chair: Chris Reynolds
AVX Corporation, Myrtle Beach, SC

Participants: E. Patrick McCluskey, University of Maryland; Dimosthenis Katsis, U.S. Army Research Labs; John Flannery, Artesyn Technologies and Scott Strand, IBM..

South Ballroom B

In his introduction to the seminar, Chris Reynolds will briefly outline the motivation behind the various lead free imperatives, and the legislative requirements being imposed on the industry.

Drs. McCluskey and Katsis will outline the impact that the lead free legislation has on conventional electronic materials, chemistries and processes. They will then outline the state of research and development of new processes, and the projected impact on manufacturing quality and field reliability.

Dr. Flannery will outline the practical impact of lead free legislation on component availability, product design, and product manufacturing processes. He will also outline conflicts that the higher soldering temperatures create with specific component and substrate technologies. In addition, he will analyze the impact for both new designs, and for situations where existing designs may have to be converted to lead free.

Dr. Strand of IBM will represent the customer perspective. He will discuss what lead free means to them with respect to marketing impact, product differentiation, and commercial necessity. Also presented will be their expectations for the impact on product cost, cycle time, quality and reliability. For new products, the speaker will present a timetable for when all new development must be compatible to the legislation, and for existing products the speaker will discuss the circumstances under which products must be converted into a compatible design.

The seminar will conclude with open discussion, including the audience, on whether or not the power supply industry is ready to adopt lead-free manufacturing.

Douglas Hopkins
State University Of New York, Buffalo, NY
North Ballroom A

This seminar provides the power electronics designer with a comprehensive description of leading and next generation power packaging techniques for power supplies and drives with emphasis on high current applications. An update is given on lead-free soldering issues and how designs are impacted by component availability and compatibility. Recent results in reliability testing of high-current density solder interconnects is also given. Attributes, processes and design rules for packaging techniques, such as multi-layered heavy-copper FR-4, copper-on-ceramic, bus bar and molded interconnect, are presented. The material is co-presented from electrical, thermal and physical perspectives.

The designer will gain familiarity with nomenclature, electrical and material characteristics, and guidelines for mixed-use of several packaging techniques. Designers will gain sufficient information to consider and select alternate packaging techniques that optimally meet their needs. Several product reviews will demonstrate electrical/physical design and identify critical packaging issues. This is an essential course for the designers who must look at other packaging design approaches to further shrink their electronics.

David A. Torrey
Advanced Energy Conversion LLC, Ballston Spa, NY
Marina 1

This course is intended for those who work with either permanent magnet or induction motor drives and desire a better understanding of how they can be controlled. The presentation will be broken up into five parts that address the operation of these machines, and how they may be controlled. Part 1 provides an overview of the basic principles of how permanent magnet motors operate. Part 2 provides similar information for the induction machine. With a basic understanding of machine operation providing the motivation, Part 3 discusses the converters used to operate the machines at variable speed. Switch specification, snubber circuits and clamps and thermal issues are addressed. Part 4 revisits the control of permanent magnet motors, discussing issues such as system modeling, control loop design, and enhancements that can improve or extend performance of the drive. Part 5 revisits control of the induction machine, also addressing modeling, control design and enhancements.

Ray Ridley, Ridley Engineering, Roswell, GA and
Vatche Vorperian, Jet Propulsion Laboratory, Pasadena, CA
North Ballroom B

1. Original PWM Model - The PWM switch model became the standard for analysis of dc-dc converters in the late 1980s. Its simple and elegant form allowed a single circuit model to be used for all dc-dc converters, replacing more tedious and cumbersome methods of analysis. The PWM switch model also allowed the proper analysis of DCM converter operation that was previously impossible, giving substantial benefits over other analysis methods. The seminar will present a brief review of the PWM switch model, and examples of its application.

2. Extension to Current-Mode Control - Within a few years of publication of the switch model, its application was extended to cover current-mode control, while leaving the switch model itself unchanged. This allowed a single model to be used for both voltage-mode and current-mode control. Since the publication of the current-mode version, numerous other papers have been published with different approaches, and some of these will be reviewed in the seminar, and compared for the first time to the original model.

3. New Ripple Extension of the PWM Switch Model - A premise of the original switch model was the averaging of the switching ripple in the inductor. While this led to a powerful analytical tool for small-signal analysis, it did not allow the user to predict ripple currents and voltages. This seminar will present for the first time a new variation of the PWM switch model which accurately predicts current ripple in converters, including "zero-ripple" converters which have eluded accurate analytical predictions.

Attendees at this seminar will leave with a powerful set of tools which will cover their small-signal modeling needs in the area of PWM power conversion, presented by the researchers who did the original work. Numerous examples will be used to highlight the practical applications of the models.

John Miller
J-N-J Miller Design Services, PLC, Cedar, MI
Marina 4

The character of automotive propulsion systems is again going through evolutionary change as gasoline-electric hybrids and diesel technologies become more accepted and compete against ever more sophisticated ICE propulsion. Today's hybrid vehicle propulsion technology is seen as a bridging action by some until affordable fuel cell propulsion becomes available in the mass market. Other, more visionary companies view hybrid technologies as essential steps leading to fuel cell hybrids and the hydrogen economy. This seminar will acquaint the motor drive and power electronics system designer with the specifications, challenges and demands of designing traction power processing systems for vehicle propulsion. The seminar will be divided into three major subsections, each addressing key attributes of the propulsion system challenge: 1) Hybrid architecture choices and their impact on vehicle performance, 2) An update on energy storage systems and sizing criteria, and 3) Electrical and mechanical system matching methodology. Vehicle driveline architectures presented will range from series, through direct and indirect parallel, to power split and electric four wheel drive. Energy systems of choice include advanced batteries, ultra-capacitors and flywheel systems. The hypothesis posed by the author is that hybrid propulsion architectures that today cost from $66 to $93/kW do not fully meet vehicle performance and economy targets.

At the conclusion of the seminar, attendees will learn why hybridization is viewed as electric supercharging and will have acquired the knowledge to more fully appreciate the methodology of designing, modeling and simulation of hybrid propulsion systems at the vehicle level.

Robert V. White
Artesyn Technologies, Westminster, CO
South Ballroom A

One of the most dreaded tasks in the industry is writing a specification for a new power supply or dc-dc converter. For the equipment OEM, errors in a procurement specification often lead to delays in new product development. For the power supplier, errors in a datasheet lead to unhappy customers. Both of these can be very expensive for all concerned.

Writing a good specification or data sheet is complicated by several factors, starting with the need to fully describe the product in four different domains: electrical, mechanical, environmental and compliance. A common hindrance is the lack of widely accepted, common terminology and test procedures.

This seminar will give you the fundamentals needed to write a specification or data sheet that is useful to both power supplier and power user. The first part of the seminar discusses the basics of creating a specification. The first item is the importance of identifying the purpose and the audience of your creation. The discussion continues with the differences between a procurement specification and a data sheet, the pros and cons of different ways of presenting requirements and creating excellent documents using common word-processing, diagramming and spreadsheet programs.

The second part of the seminar describes how to structure the document for completeness and ease of use. The importance of specification elements such as a revision table, tables of contents and figures and referenced documents will be presented. Suggestions on structuring the electrical, mechanical, physical, environmental and procurement/business sections will be presented.

The third part gives a mid- to high-level look at the best ways to write specifications for electrical parameters, protection and housekeeping functions including signal interfaces, compliance to safety and EMI regulations and standards, environmental requirements and other items as time allows.

Rakesh Dhawan
Wavecrest Laboratories, Dulles, VA
Avalon Room

This seminar will cover the fundamentals of DSPs and what makes digital signal processors effective for power supply design.

For power supplies, which require real-time performance, DSPs are a great choice. DSPs offer a great deal more in terms of increased functionality, features, flexibility and reliability. DSP based design can offer reduced component cost in addition to modular and scalable designs.

DSP based power supply designs open the door to a host of new design opportunities such as enhanced fault tolerance, enhanced fault indication, real-time adaptability, and most of all upgrade-ability. However, the design methodology for the use of DSPs in power supplies introduces a significant complexity. Power supply and system grounds, RFI and EMI design considerations, Feedback and stability etc. pose new challenges. This seminar addresses some of those challenges.

The seminar discusses examples of DSP based power supply design for buck, boost, buck-boost, flyback, push-pull, half-bridge and full-bridge topologies. Texas Instrument's TMS320LF2402A DSP is used for these examples. The seminar also discusses some PSpice based simulation results for these designs. How such simulation results can be used for proper algorithm development.

Seminar Chair: Cristian Marin, Consultant

Participants: Walt Benecki, Industry Consultant, Elgin, IL and Frank Ferber, Celestica, Toronto, Ontario

South Ballroom B

Drawing from years of experience guiding clients in their move to China, Walt Benecki will give his perspectives on the economic and operational issues of moving power manufacturing to China. Specific case studies will be cited to illustrate both the opportunities and challenges that this transition can create for a power supplier, and also on the critical success factors in making a successful transition. Walt will focus specifically on the geographic move from domestic to Asia manufacturing.

Frank Ferber is involved in actively transitioning power companies with captive domestic manufacturing capacity to an outsourced business model in China. Frank will outline the opportunities and challenges created by such a change in business models, citing case studies and actual customer situations where applicable. He will focus specifically on the conceptual move from captive to outsourced manufacturing, and also on the critical success factors in making this transition.

The seminar will conclude with an interactive discussion on whether or not North American and European manufacturing can be competitive in the global marketplace.

R. David Middlebrook
California Institute Of Technology, Pasadena, CA
North Ballroom A

This intermediate level tutorial introduces the General Feedback Theorem (GFT), which is the culmination of design-oriented analysis approaches presented in five previous APEC Seminars.

Feedback systems are usually designed with the familiar single-loop block diagram in mind. Various nonidealities, such as unavoidable minor loops and direct forward transmission, make the single-loop block diagram progressively less useful, especially at higher frequencies.

The GFT defines a "natural" block diagram model that is identical in format to the single-loop model that is conventionally assumed, thus providing a desirable link between general feedback theory and a detailed circuit diagram analyzed in terms of factored pole-zero transfer functions.

The GFT is illustrated on a potentially unstable Darlington emitter/ source follower stage, and leads to design criteria that limit the maximum peaking regardless of the value of the load capacitance.

Another example is a two-stage feedback amplifier having various nonidealities, including loading interactions at all points, direct forward transmission, and two minor loops.

The GFT is computer friendly, and emphasis is on the numerical and graphical results obtained by use of an Intusoft ICAP/4 circuit simulator.

Mehrdad Ehsani
Texas A&M, College Station, TX
Marina 1

A new technology, for quick and low cost development of controllers for adjustable speed motor drives, is presented and demonstrated. The technique of using commercially available off line and real time simulation packages for motors and their drive converters is taught. This technology is used for hardware in the loop to develop actual controllers for the drive, before the construction of the actual drive or its load. The applications of this new design technology are in short development cycle products, high cost motor drives, critical mission motor drives, drives and loads not yet developed, such as in automotive traction, manufacturing, military, aerospace, and in research and education.

The course includes review of controls for dc, induction, brushless dc, and switched reluctance motor drives. Development of various motor drive models in MATLAB/Simulink™ is presented. Conversion of these off line models to real time simulation using RT-LAB™ is taught, including issues of high fidelity and real time sampling rate. Example cases are developed theoretically and demonstrated experimentally in real time. The course ends with audience applications clinic and hands on participation in class. This is an in depth course suitable for motor drives engineers of all levels and applications.

Rob Martinelli
Analytic Artistry, Temecula, CA
North Ballroom B

A systematic method is presented for building a SPICE model for a PWM converter that is capable of accurately representing the behavior of the converter in continuous and discontinuous conduction modes at frequencies up to one-half the switching frequency. The seminar describes five valuable analysis techniques for building accurate models: Averaging Circuits, Circuit Solvers, Equations Solvers, Time Delays, and separation of the dependent variable (ΔIL) from the independent variable (IL). The five techniques are then demonstrated through two examples: A forward converter with current mode control and a discontinuous mode flyback regulator.

The CD for the seminar will also include models for a flyback converter and a two phase push-pull converter with a current doubler output filter.

Dorin O. Neacsu
Consultant, Lexington, MA
Marina 4

More and more features are added to modern automobiles and almost all of them rely on a power electronics system. This tutorial analyzes the market of automotive low voltage power electronics systems used in body system control, chassis control, driver information systems, electronic power steering, powertrain systems, and safety/security systems.

The main focus is on understanding each application with all mechanical details necessary to define the specific requirements for the power and control system. The impact of converting from 14 V to 42 V automotive systems is outlined with examples based on the first systems to benefit from this conversion such as the electric power steering systems, electric brakes and engine cooling fans. Finally, auxiliary on-board sources of energy are analyzed.

This seminar will benefit all power electronics engineers regardless of their levels of experience. For both novice and experienced engineers, the challenges of modern automotive applications can represent an interesting topic.

Kevin Granlund, EMC; Ron Guly, HP; Jeff Layton, Dell;
Gary Fernandez, Cisco Systems and Ken Piper, Cisco Systems
South Ballroom A

In today's business environment, with ever decreasing development time, decreasing cost and increasing quality, an "Oops!" can be very expensive. Products introductions to the market are no longer ramps, they are step functions. A problem in a power supply is expensive not just for the cost of replacing or repairing the defective product but also in the cost of a large number of field replacements and lost opportunity for the OEM. This makes it most important that power supplies-and power suppliers-are properly qualified to minimize the chance that defective or inadequate product reaches the field.

In this seminar, four of the electronics industry's leading OEMs will speak on their leading edge practices for qualifying power supplies and power suppliers. Kevin Granlund of EMC and Ron Guly of HP will speak their company's processes for qualifying power supplies. Jeff Layton of Dell and Scott Wilson of Cisco Systems will speak on qualifying power suppliers. This is an unprecedented and unequaled opportunity to learn from the "best of the best" what it takes to succeed in today's demanding global markets. If you are either a power supplier or power consumer, this seminar is not to be missed.

Dragan Maksimovic and Regan Zane, University Of Colorado, Boulder, CO and
Aleksandar Prodic, University of Toronto, Toronto, Ontario
Avalon Room

The purpose of the seminar is to introduce practical digital controller design and implementation techniques for high-frequency switching power converters. Starting from standard analog controller architectures and design principles, sampling effects and basics of discrete-time analysis and modeling in time and frequency domains are introduced. Examples are used to illustrate simple digital compensator design techniques, as well as characterization, selection and implementation of A/D converters and digital modulators. Quantization effects and limit-cycling issues are also discussed. Three complete design examples are used to present practical design and implementation options, CAD tools, simulation techniques, and experiments: (1) a high-performance DSP controlled PFC, (2) an FPGA-based development system for a digitally-controlled ballast, and (3) a custom digital IC for a high-frequency switching power supply. The seminar will be presented at a basic to intermediate level. Knowledge of basic converter operation and standard analog controller design will be assumed.

Seminar Chair: Chris Stratas
Celestica, Toronto, Ontario

Participants: Cristian Marin, Consultant; Nick Antonacci, Delta Energy Systems and Ron Guly, HP

South Ballroom B

Cris Marin will open the seminar with an analysis from a theoretical and statistical point of view the impact that different levels of incoming inspection, in process inspection, test, burn-in, and highly accelerated stress screening can have on field reliability, and the level of defects passed on to a customer. This analysis will be based on typical process capabilities, inspection efficiencies, and test coverage, as well as customer requirements for a variety of different power technologies. If a problem is seen at any point within the factory, can it truly be contained?

In his discussion, Nick Antonacci will outline the practical approaches being used within power supplies today to meet customers' quality and reliability requirements. In addition, Nick will analyze the relative quality impacts caused by design issues, incoming parts, process defects, and workmanship, and the effectiveness of conventional screening techniques to contain these defects within the factory. Finally, Nick will discuss the relative costs involved in preventing, screening and containing quality issues at various points in the total fulfillment process.

In the third section of the seminar Ron Guly will discuss the requirements he demands as a power customer, and the typical ways in which suppliers are striving to meet those requirements today. Ron will illustrate examples of how defects found in the factory environment have been passed through to the field by way of incapable manufacturing processes, insufficient test processes, or incomplete closed loop quality programs that prevent suppliers from properly containing and correcting these issues. Finally Ron will extrapolate forward in time as complexities and densities increase, to discuss how suppliers must step up to improve quality performance under more demanding technical and market conditions.

The seminar will conclude with open discussion, including the audience, on whether or not field reliability goals can be achieved without factory stress screening?

F. Dong Tan
Northrup-Grumman Space Technology, Redondo Beach, CA
North Ballroom A

The forward converter remains an industrial workhorse in low-power dc-dc conversion. While previous discussions by the same author presented recent developments and performance comparison in advanced circuit topologies, current doublers, and synchronous rectifiers, this seminar focuses on practical design aspects of input and output filters, including some most-recent developments in the field.

This seminar is intended for entry- and intermediate-level design engineers who are facing increasingly tight EMI/EMC requirements, often coupled together with constant pressure for cost and schedule. A solid knowledge about practical filter design that ensures first-pass design success is increasingly appealing to engineers at all levels.

This seminar starts with an overview of basic one-stage and two-stage input filter configurations. It then introduces an important concept of power filter damping. Optimal single-resistor damping and non-dissipative damping techniques are then introduced. Two useful configurations for input filter design are then discussed and simple design steps are provided. These are applicable for many high-performance designs, including military and space applications. Practical output filter designs for capacitive and inductive loads are then discussed. The issue of potential instability introduced by interaction between an input filter and a switching regulator is discussed with practical design guidelines.

The coupled inductor, as a general technical means for ripple steering, is then introduced, enabling a designer to achieve zero ripple in both input and output. Practical limitations of this technique are also presented. Common-mode filter design is also discussed.

Peter Bardos
Artesyn Technologies, Youghal, Ireland
Marina 1

After a brief introduction to EMC concepts, the seminar will treat in some depth the EMI characteristics and behaviour of components, including that of PWBs. Throughout this seminar the emphasis will be on practical knowledge and understanding, not just on information, avoiding complicated mathematics.

Magnetic and electric fields, and their sources, victims and transmission paths in power supplies will be explored. The problems and solutions will be illustrated by real components and examples from actual power supply designs.

The characteristics and effects of invisible components and strays are also explored, and this will lead to a point-by-point method of laying out optimal PWBs that work first time.

The principles of EMC fault-finding, filter design and layout, and methods of calculating, measuring consistently, and characterising EMI are introduced.

This seminar will lead to an understanding of the engineering principles of EMC design, and provide practical solutions to EMC problems.

Dean Venable
AblePower Corporation, Westwood, MA
Marina 4

This is a seminar for people who actually have to stabilize feedback loops and want them to be "all that they can be". The approach is primarily graphical but equations will be presented for those who require them. Emphasis will be on the "big picture" and the goals, but enough detail will be included so that any attendee should be able to optimize a feedback loop at the conclusion of the seminar. Voltage mode and current mode control will be covered, for both buck-derived and boost-derived circuits. The concept of "K-Factor" for optimizing loop performance will be covered in detail. New material will be presented on modeling, optimizing, and testing digital feedback loops, and how PI and PID compensation in digital loops relate to analog feedback loop design.

Dan Jitaru
Delta Energy Systems, Tucson, AZ
North Ballroom B

The seminar will present a comprehensive overview of the rectification techniques for low and high voltage application. A full section is dedicated to the synchronized rectification a major step forward in the quest for higher efficiency. There will be presented different methods of drive and control for synchronized rectifiers. There will be presented driven and self-driven synchronized rectification methods applied to different topologies. The seminar will also show some future trends in improving the efficiency of the synchronized rectification.

Another key chapter is dedicated to high efficiency rectification wherein the limiting factor is the reverse recovery of the rectifiers. A focal point will be the soft commutation technology applied to the rectifiers with applications not only in high voltage but also in low voltage, using synchronized rectification and higher frequency of operation.

The presentation will be highlighted with design guidance, design example and experimental results.