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Table of contents
  1. APEC 2024 Breaks records, APEC Returns to Atlanta in 2025
  2. PSMA and CPSS Meet at APEC 2024
  3. PSMA Annual Meeting at APEC 2024
  4. Meet Your Directors (Ada Cheng)
  5. Welcome to PSMA
  6. IWIPP 2025 to be Held in Tuscaloosa, AL in 2025
  7. EnerHarv 2024 in Perugia, Italy
  8. Book Offers Further Instruction On Advanced Methods Of Circuit Analysis
  9. Ecodesign, Reuse, Repair, Prolonging Lifetime and New Technology – Is it the new paradox?
  10. Events of Interest – Mark Your Calendar
Contents | Next->

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Previous issues of update: Q2_2023 | Q3_2023 | Q4_2023

PSMA UPDATE is published and distributed via e-mail quarterly by the Power Sources Manufacturers Association. Send editorial information and comments to:

P.O. Box 418
Mendham, NJ 07945-0418


(973) 543-9660
Web Site:

Publisher: Fred Weber   Managing Editor: Kristin Colbert

Permission to reprint information and articles as published is granted: a courtesy line is appreciated.

Membership in PSMA is open to any organization or corporation involved in the power sources and supplies industry. For membership information, visit our website or contact us by fax, telephone or email.

If you or anyone in your company is interested in getting on the distribution list for future issues of PSMA UPDATE, please send e-mail to: Be sure to include your name and the name of your company.



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APEC 2024 Breaks Records for Registrations and Packs the House – Plans Now Underway for APEC 2025 in Atlanta Next March

A PEC 2024 was a record year. This year's event was benchmarked against APEC 2019, the last event before the COVID impact as well as the last time the event was held in California (Anaheim). We were expecting to approach that year's attendance of over 5,900. Our expectations were exceeded with registrations of over 6,100. In 2017, the last time APEC was held in Long Beach, we shared the Convention Center with another conference and exhibition. This year, we had the place to ourselves and used every square foot of this beautiful facility. A big thank you to Tim McDonald, APEC 2024 General Chair and the Organizing Committee for a job well done!

Now it's on to APEC 2025, March 9-13 at the Atlanta Convention Center at AmericasMart. This is first time for APEC to return to Atlanta since the event hosted fewer than 1,500 attendees at the Weston Peachtree Hotel back in 1997. Incoming General Chair, Tony O'Gorman, expects APEC 2025 to continue its record-breaking role as the "Premier Event in Applied Power Electronics™."

I recommend that you check the website in the weeks ahead ( and watch for announcements about the calls for Technical Session and Industry Session submissions as well as proposals for the Professional Education Seminars.

Technical Sessions
Prospective authors will be asked to submit a digest explaining the problem that will be addressed by the paper, the major results, and how this differs from the closest existing literature. Papers presented at APEC must be original material and not have been previously presented or published. The principal criteria in selecting digests will be the usefulness of the work to the practicing power electronic professional. Reviewers especially value evidence of completed experimental work.

Professional Education Seminars
Professional Education Seminars at APEC 2025 will address the need for in-depth discussion of important and complex power electronics topics. Seminars are three-and-a-half hours (including breaks) in length, can range from broad to narrow in scope, and can vary from introductory to advanced in technical level. Topics are to address the practical issues of the specification, design, manufacture and marketing of power electronic components, products, and systems.

Industry Sessions
The Industry Sessions run in parallel with the technical sessions and have proven to be very popular. Submissions are due by late August. Speakers are invited to make a presentation only and will not be submitting a formal paper. The target audience for these sessions differs from the engineers in typical technical sessions and may include system engineers/architects and business-oriented people such as purchasing agents, information technologists, regulatory agencies, and other people who support the power electronics industry.

Make your plans to be part of APEC 2025. Be sure to add this important event to your calendar and in your budget for next year. And do your part to make it an even better conference by volunteering to be on the peer-review panel in areas where you are qualified. See you in Atlanta.

Provided by Greg Evans,
APEC 2025 Publicity Co-Chair



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PSMA and China Power Supply Society Meet at APEC 2024

A fter not attending APEC since 2019 due to the COVID Pandemic, members of the China Power Supply Society (CPSS) met with members of PSMA at APEC 2024. Members of both organizations were happy to get together after a five year hiatus and quickly worked to reestablish existing relationship and forge new bonds. The two organizations met in the Seaview Rotunda at the Hyatt Regency Long Beach and enjoyed some light refreshments while networking and planning future endeavors. PSMA representatives included the PSMA Executive Committee, the PSMA Administrative Office and other interested PSMA Board Members. CPSS was represented by their Executive Committee and other relevant members.

The two organizations talked about plans for APEC 2024 conference and the upcoming annual CPSS conference to be held later this year. Many areas of synergy were identified, and CPSS was invited to get involved in PSMA's EnerHarv 2024 workshop to be held in Perugia, Italy in June of this year. All attendees were thankful for the opportunity to meet once again after a long break, and plans were made to meet at APEC 2025 in Atlanta, GA next year.

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PSMA Annual Meeting at APEC 2024

O ver 50 PSMA members and guests attended the PSMA Annual Meeting, held at the Hyatt Regency Hotel in Long Beach, CA. The buffet breakfast before the start of the meeting provided attendees an opportunity for networking and reconnecting with colleagues. Outgoing chair Fred Weber officially opened the meeting by welcoming all the attendees and asked each to briefly introduce themselves. Among those present were many of the recipients of the APEC Student Attendance Support provided for the twelfth straight year by IAS, PELS and PSMA.

Following the introductions the Chair's gavel was officially handed off by Fred Weber to Trifon Liakopoulos. Trifon thanked Fred for his service to PSMA and said he was looking forward to the challenge of leading PSMA for the next two years.

After the passing of the gavel the nominees for the open three-year terms to the PSMA Board of Directors were introduced. Votes were collected during the approval of the 2023 Annual Meeting minutes and the election results were announced after a break midway through the meeting. Three board members were reelected to serve a second term:

David Chen
Ajay Hari
Renee Yawger

In addition, Brian Zahnstecher was elected to fill the seat vacated by Tim McDonald who had served two consecutive terms and was not eligible for reelection. Tim has agreed to stay on as Treasurer for the foreseeable future.

Trifon then gave the Chair's Report highlighting the priorities of the incoming Executive Committee including creating a foundation for near- and long-term growth, reviewing and optimizing administrative procedures, supporting APEC, and strengthening our relationship with other organizations including iNEMI, IPC, PELS, EPSMA, ITEC, and CPSS.

As Trifon was concluding his remarks he asked outgoing Chair Fred Weber to present a new award created by the Executive Committee. Fred introduced the Joe Horzepa Lifetime Service Award. The Joe Horzepa Lifetime Service Award was named in honor of long time PSMA Executive Director Joe Horzepa and is intended to honor PSMA members who have served PSMA for at least 10 years and been nominated by a committee led by the PSMA President. The award consists of a large, nickel-plated award with plates to engrave up to 30 recipients which will be kept by the PSMA Administrative Office and updated each year. In addition, each award recipient will receive a smaller award suitable for displaying in their office. Fred said the intention is to present the first recipient of the Joe Horzepa Lifetime Service Award at APEC 2025 to coincide with PSMA's 40th anniversary.

Fred presented the two smaller award options to Joe Horzepa who was honored and flattered to have a lifetime service award named in his honor.

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Meet Your Directors

Four members of the Board of Directors are elected at the PSMA Annual Meeting held every year during the APEC conference. Each Director serves a three year term and is eligible to be reelected for one additional term.

In this issue we would like to introduce you to Ada Cheng.

Ada Cheng is a Technical Marketing Consultant with AdaClock since 2008. In addition, she has partnered with Anagenesis, to research and publish the "Power Supply in a Package (PSiP) and Power Supply on a Chip (PwrSoC) market reports. She has been involved with the PSMA since 2002 and joined the PSMA Board of Directors in 2019 and in 2023. Currently she is an active member of the Marketing, Energy Management, Energy Storage, Industry-Education, and Reliability committees.

One of her biggest contributions was challenging the PSMA committees to support APEC in some tangible way such as creating and running industry sessions, producing professional education seminars, suggesting key speakers for plenary, etc. As a result, the amount of industry participation in APEC has grown, and the conference has flourished while many other technical conferences have not. Lately she is leading the mentorship program at APEC, working on an energy efficiency strategies presentation, and co-chairing an industry session at APEC.

Furthermore, Ada was an invited member of the APEC conference committee from 2003 to 2015 primarily as the OEM Initiative Chair which developed the Industry Sessions.

Previously Ada was a corporate marketing manager at International Rectifier (now Infineon), a market analyst at Gartner Dataquest for analog ICs, and held various electrical engineering roles at Motorola Semiconductor Products Sector (now NXP Semiconductors and ON Semiconductors). Ada received her MBA from Arizona State University and her BSEE from Carnegie Mellon.


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Welcome to PSMA
   We are pleased to welcome six new member companies this quarter. If your company is interested in becoming a member you can learn about the benefits of membership by visiting our website

Eclipse Technologies
Ed Allen
200 S. Executive Drive, Suite 101
Brookfield, WI 53005

Eclipse Technologies is a manfacturer's rep firm doing business in Wisconsin and Illinois. Eclipse focuses on representing manufacturers who are technology leaders in their field. Leveraging one of the industry's broadest intellectual property technology portfolios Eclipse Technologies providers customers with complete system solutions focused on industrial, medical, security, military, communications, computing and automotive markets.


Elsis Electronic Systems, Inc.

Murat Burak Türk
Business Development Specialist
Ivedik Osb Mah. 1465. Cad. No: 43-45
06378 Ostim Yenimahalle
Ankara Türkiye 06378
Telephone: +905413714571

Elsis Electronic Systems, Inc. was established in 1971 in order to meet domestic needs and improve export opportunities. Elsis Electronic Systems, Inc. has designed and manufactured automatic voltage regulators, uninterruptible power supplies and various protection devices for use in laboratories, hospitals, factories, universities and the military.

Equipping its products with high performance, small sizes, high security and compliance with current regulations Elsis Electronic Systems, Inc. has taken its place among the leading companies in Türkiye with its innovations in power electronics. The staff of Elsis Electronic Systems, Inc. consists of experienced engineers, technicians and administrative personnel and the company is a leader in power electronics both nationally and internationally.


OPUS Solutions, Inc.

Kris Ponmalai
27111 Aliso Creek Rd
STE 145
Alisi Viejo, CA 92656
United States
Telephone: 9497357071

OPUS Solutions, Inc. is a developer and manufacturer of DC-DC power supplies, rugged computers and embedded controllers and systems for the Automotive, Medical and Industrial markets. OPUS Solutions is committed to providing customers with superior products of high quality that meet customer requirements and exceed expectations.

OPUS Solutions, Inc. focuses on the US and India as their primary markets. They are ISO 9001:2008 and AS9100D certified. OPUS Solutions, Inc. products include vehicle computers, vehicle power supplies, accessories and cables as well as custom products.


SiliConch Systems Private Limited
Vishnu Mohan Pusuluri
#591, 15th cross, 14th main
Sector 4, HSR Layout
Bangalore, Karnataka 560102
Telephone: 9880370534

SiliConch Systems Private Limited was founded in 2016 by a team of ex-Intel engineers and quickly established itself as a groundbreaking player in the semiconductor industry. Based in Bengaluru, this innovative company specializes in semiconductor product development, focusing on Intellectual Property (IP) and Fabless Integrated Circuit (IC) solutions.

SiliConch's core expertise lies in creating smarter, integrated solutions with high-performance and low-power analog mixed signal designs. These designs are pivotal in areas such as fast battery charging, power management, and high-speed data transfer, catering to a diverse range of products including smartphones, PCs, automotive, IoT, and accessories.


Tagore Technology
Amitava Das
601 W Campus Drive, Suite C1
Telephone: 8472876051


Tagore Technology is a fabless GaN semiconductor company. Tagore's product line include power GaN as well as RF GaN IC's. Tagore's RF GaN IC's are used in LMR/PMR as well as tactical radios. Tagore's power GaN products are used in various switching mode power supplies.

Tagore Technology was founded in January 2011 to pioneer Gallium Nitride-on-Silicon (GaN-on-Si) semiconductor technology for Radio Frequency (RF) and power management applications. Their advanced proprietary, technologies and devices significantly reduce complexity, size, weight and power consumption of system solutions at an aggressive price point - delivering dramatically improved power conversion Figure of Merit compared to Silicon solutions. They are a fabless semiconductor company with design centers in Arlington Heights, Illinois, USA and Kolkata, India. Their R&D team is dedicated to developing disruptive solutions leveraging wide bandgap technologies that help address RF and power design challenges for their customers and accelerate time-to-market for a wide range of applications from 5G cellular infrastructure to consumer, automotive and defense and security. They partner with leading semiconductor foundries and assembly houses to deliver products that offer premium quality and proven high reliability.


TRAFOLO Engineering
Juris Vencels
CEO, Simulations
Baznicas 5-2
Jaunolaine, Olaines nov.
Telephone: +371 24786762

TRAFOLO Engineering was founded in 2017 with the release of its first product, software for use in metallurgical and plasma physics. Their software products reflect many years of experience that was gained from dozens of industrial and research projects. TRAFOLO's goal is to make simple but capable simulation applications for various industrial products and processes involving electromagnetics and heat transfer.

TRAFOLO is a 3D finite element method (FEM) simulation software that focuses on coupled electromagnetics and heat transfer. TRAFOLO is a specialized simulation software for magnetics that helps R&D teams prototype virtually and eliminate critical design errors before the first physical prototype is built. While there are many FEM packages around, TRAFOLO provides a workflow that requires less training and is more efficient. Models and features that are relevant to the magnetic component design engineers are ordered and grouped which helps to automate the most time-consuming tasks.

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IWIPP 2025 - International Workshop on Integrated Power Packaging

Tuscaloosa, AL, USA in association with The University of Alabama

P SMA is excited to again be sponsoring the next edition of IWIPP which will be held April 8-10, 2025 at The University of Alabama in Tuscaloosa, AL USA. IWIPP is a growing and dynamic power technology workshop with excellent speakers and networking opportunities. The contents of IWIPP 2025 will include a set of keynote addresses from leading experts and a broad range of technical sessions.

The International Workshop on Integrated Power Packaging (IWIPP) brings together industry, academic and government researchers in the field of power electronics components, electrical insulating materials, and packaging technologies to facilitate and promote the development and commercialization of high-density and high-efficiency power converters. This multi-disciplinary workshop includes invited presentations, contributed papers, and a poster session.

Packaging and related technologies are the key to creating efficient and high-density power conversion systems and applications. Attendance at this important event will keep you and your colleagues on the cutting edge.

Additional information regarding the workshop can be found at the conference website: For questions and/or inquiries, contact:

Sponsored by:
Power Sources Manufacturers Association (PSMA)
IEEE Power Electronics Society (PELS)
IEEE Electronic Packaging Society (EPS)
IEEE Dielectrics and Electrical Insulation Society (DEIS)
European Center for Power Electronics (ECPE)

Organizing Committee:
Andy Lemmon, General Chair, Univ. Alabama
Nick Baker, Technical co-Chair, Univ. Alabama
Arthur Boutry, Technical co-Chair, Univ. Alabama
Yue Zhao, Financial Chair, Univ. Arkansas
Cyril Buttay, Publications Chair, INSA-Lyon
Ivana Kovacevic, Publicity co-Chair, ETH Zurich
Xiaoling Li, Publicity co-Chair, Univ. Arkansas
Jim Gafford, Sponsorship Chair, Univ. North Carolina Charlotte
Brian Narveson, PSMA Representative, Narveson Consulting

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The Third International Energy Harvesting Workshop, EnerHarv 2024 will be Held In Person in Perugia, Italy

E nerHarv 2024 will bring together experts from around the world working on all technical areas relevant to energy harvesting, power management and its IoT applications ( This non-profit workshop, organized and sponsored by the Power Sources Manufacturers Association (PSMA,, will be held at Hotel Giò Congress Center in majestic city of Perugia, Italy from June 26 to 28. The event shall be hosted by the Noise in Physical Systems (NiPS Lab), Dept. of Physics & Geology, University of Perugia (UNIPG,

This builds on the vision of EnerHarv to create a focal point for experts and users of energy harvesting and related technologies to share knowledge, best practices, roadmaps, experiences and provide opportunities for collaboration to increase the uptake of such technologies. The workshop is targeted at a broad audience from industry and academia working on materials and devices for energy harvesting and storage, low-power sensors and circuits, micro power management, and their applications in powering IoT devices for health and environmental monitoring, assisted living, and monitoring of equipment and buildings. It will comprise presentations (invite only), demos, poster, panels sessions and generous amounts of time for networking activities. NEW IN 2024: dedicated booklet (with professional reference, DOI, ISBN, etc.) of proceedings for optional opportunity to include supporting materials optional to those presented live at the workshop. There is an OPEN call for demonstrations and posters.

Keynotes Speakers
Prof. Luca Gammaitoni (Italy) University of Perugia Dr. Daniela Iacopino (Ireland) Tyndall Institute Joshua Wright (USA) Ambient Photonics

The event will be held jointly with the NiPS Summer School "Frontiers in Energy Harvesting", taking place from June 24 to 25 ( in Perugia at Hotel Giò. This is a fantastic opportunity for early-stage researchers and professionals to connect with the future of energy solutions.

Registration will open Mon, 12 Feb with special, early-bird rates and open call for posters and demos.

Roberto La Rosa, PhD
Ultra-low Power Applications Team Manager STMicroelectronics
Mike Hayes
Head of Group, ICT for Energy Efficiency
Tyndall National Institute
Francesco Cottone
Associate Professor
University of Perugia
Brian Zahnstecher

Thanks to all the sponsors that make it possible!

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Book Offers Further Instruction On Advanced Methods Of Circuit Analysis

The Fast Track to Determining Transfer Functions of Linear Circuits: The Student Guide, Christophe Basso, 267 numbered pages, 4 index pages, glossy soft cover, 8.5 × 11 inch, Faraday Press, ISBN 978-1-960405-19-7, 2023, $54.95.

Reviewed by Dennis Feucht, Innovatia Laboratories, Cayo, Belize

Author Christophe Basso has designed converter control ICs for ON Semiconductor in Toulouse, France and has written related books, such as Transfer Functions of Switching Converters: Fast Analytical Techniques at Work with Small-Signal Analysis,[1] which was previously reviewed in How2Power Today. This earlier work and the book under review here are compendiums of methods of passive and active circuit analysis that reduce the amount of mathematics that otherwise would be required when applying Kirchhoff's current and voltage laws (KCL, KVL) and Ohm's Law (ΩL).

Somewhat higher level than those basic circuit laws are the node-voltage and loop-current methods. Even higher-level laws are presented in undergraduate passive-circuits classes such as the maximum power-transfer theorem but they are few.

Whether you are fast or slow, the methods presented in this book are conceptually more abstract than basic circuit laws and are derived from them mathematically as theorems. They impose various conditions on the circuit that simplify the application of basic circuit laws and simplify analysis.

The history of development of higher "design-oriented" circuit theorems is shown in the figure (taken from reference[2]). Major advancements in this development tree are open-circuit time-constant (OCTC) methods for finding poles, leading to the Cochrun-Grabel method and the Extra-Element Theorem (EET) of R. D. Middlebrook that includes short-circuit time-constants (SCTCs). From these follow related theorems, the impedance EET and tabular nEET.

Figure. A historical development of higher (more abstract) circuit theorems and methods of the past.

Beyond the historical developments in circuit analysis depicted in the figure, there were other refinements and restatements of these theorems by Vatché Vorpérian.[3] And following his lead are Basso's books.

This book is a sequel to reference [1] in that it works out in some detail in chapters 5 through 7 the analyses of commonly-encountered circuits with one to three reactive elements. Before presenting these analyses, the first four chapters explain the techniques and the concepts supporting them with simpler examples.

The first chapter covers transfer functions, their poles and zeros from reactive elements connected across circuits as ports, their open- and short-circuit time-constants, and the normalized form of transfer functions as providing more insight into circuit poles and zeros than the canonical form. Port resistances with reactive elements removed (open) or other ports shorted provide time-constant resistances.

Circuits are illustrated in color, sometimes with pictures of test equipment as sources and component pictures as comprising a network (circuit). Active circuits start as op-amps, but on page 31, a simple common-emitter NPN BJT circuit is shown as an example, with a two-element hybrid-π model—a good place to start in incrementally modeling BJTs.

Chapter 2 introduces design-oriented methods. At frequency extremes of s = 0 Hz (or 0+ Hz for incremental circuits) and s → ∞, capacitance and inductance are either open-circuit or short-circuit. Circuits like the RC integrator and differentiator demonstrate how to determine the pole from the OCTC and the zero (for the differentiator) from the SCTC.

Expanding to second-order (two-reactance) circuits, the time-constants (TCs) are determined by the Cochrun-Grabel method (C-G) for poles as a triangular table. The EET expands the method to include zeros. Basso has his own nomenclature for designating the TCs, and it is equivalent to C-G, the EET, and the nomenclature used in reference [2].

Chapter 3 is about finding circuit zeros, the frequencies (or corresponding time-constants) where the output is zero. Basso's method of finding zeros is that of the EET—of adjusting sources to null the output. At first this might seem obfuscating, but in the method, it is quite simple. The procedures follow what was originally introduced by Middlebrook in the Extra-Element Theorem (EET) which produces both the poles and zeros of the circuit transfer function.

The latter part of chapter 3 works through the extended and rather complicated (though important) example of a BJT with external emitter resistance. Basso is careful to include numerous steps to not leave any reader behind. (This is also worked out in reference [2] under "General Single-Stage CE Gain" by following a different path in the construction of the formidable transfer function, applying the same circuit theorems.)

Chapter 4, "Generalized Transfer Functions," has an emphasis on SCTCs for finding zeros and higher-order coefficients in the denominator (poles) and numerator (zeros) polynomials. It completes the general procedure which is powerful in determining complicated yet exact transfer functions for even some of the most common circuits in designs, yet often is left without in-depth analysis in the electronics literature because of the extensive amount of algebra required.

Chapters 5 through 7 present many detailed circuit solutions beginning with first-order (one-reactance) circuits in chapter 5. These circuits have no resonance and are easier to derive. Basso also includes the time-domain step response that models what is seen while probing the circuit driven by a square-wave, and Bode plots are presented for frequency-response analysis. Everything is in living color.

Chapter 6 is more complicated, with non-minimum-phase circuits and resonances. Yet second-order circuits have second-degree (quadratic) equations and can be solved with the quadratic formula, thereby factoring the poles or zeros into the desired normalized form of transfer functions.

The third-order circuits of the last chapter pose the polynomial factoring problem. Although there is a method for solving cubic equations, it is not a simple formula like the quadratic equation, and the book resorts to simulation. It is often possible for real circuits with widely separated poles or zeros to approximate them as lower-degree polynomials, though approximations do not appear in the book; it is about exact derivations.

Appendix A summarizes the method discussed throughout the book

What does not appear in the book about transfer functions is a comparison of nodal versus OCTC time-constants. They are not the same and this can be a confusing topic when learning circuit dynamics. Another omitted topic is analysis of a generalized amplifier, with general input, output, and feedback impedances and a quasistatic Gm gain. When solved, the three time-constants have equivalent circuits that make analysis of the amplifier simpler.

Another high-level theorem is Miller's theorem, but less common is the frequency-dependent version of it. Finally but not least important is the high-frequency modeling of BJT and feedback amplifiers that reveals why spurious oscillations occur in circuits. These topics go somewhat beyond the range of what is covered in this book, which remains focused on transfer-function derivations.

This is another good book from Basso who patiently explains (in color) each procedure step-by-step, then applies it to various examples. It is somewhat like the old Schaum's Outline Series books which served the same role.

I recommend this book for anyone who has not yet mastered dynamic circuit analysis at the component level. The topic will not go away. Basso uses simulations to check the equations for agreement, but simulations do not give insight into the effects of circuit parameters on the behavior of the circuit. Mathematical analysis does.


1. Transfer Functions of Switching Converters: Fast Analytical Techniques at Work with Small-Signal Analysis by Christophe Basso, Faraday Press, 2021, reviewed in How2Power Today.

2. Circuit Dynamics: Design-Oriented Analysis, Dennis L. Feucht, Innovatia, 2013, page 1.

3. Fast Analytical Techniques for Electrical and Electronic Circuits, Vatché Vorpérian, Cambridge
University Press, 2002.

About The Author

Dennis Feucht has been involved in power electronics for 40 years, designing motor-drives and power converters. He has an instrument background from Tektronix, where he designed test and measurement equipment and did research in Tek Labs. He has lately been working on projects in theoretical magnetics and power converter research.

To read Dennis' reviews of other texts on power supply design, magnetics design and related topics, see How2Power's Power Electronics Book Reviews.


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Ecodesign, Reuse, Repair, Prolonging Lifetime and New Technology – Is it the new paradox?

T he European Ecodesign is well known for energy related issues such as energy efficiency and standby energy consumption, and many detailed articles have been written on this topic. As one of the key elements of the European Green Deal strategy there is another, less well known aspect to Ecodesign that's about reducing waste and granting consumers the 'Right to Repair' thus prolonging the lifetime of equipment. Clearly the time is right for 'Right to Repair' to be addressed, initially for consumer products that are the visible part of the iceberg, forming part of the much bigger problem of changing our way of working and dealing with the issue of prolonging the lifetime of equipment whilst developing a circular economy. Many business segments will be highly influenced by the new European Directives and will need to figure out new ways to deal with obsolescence.

So how will the power supply industry embrace this change and how could it contribute to prolonging the lifetime of equipments and to reduce waste?

New EU rules to make sustainable products the norm

As announced in the EU Circular Economy Action Plan, the Commission has proposed new rules to make almost all physical goods on the EU market more environmentally friendly, circular, and energy efficient throughout their whole lifecycle from the design phase through their daily use, repurposing, and end-of-life. As part of the Action Plan dated June 2023 the Environment Committee put forward a proposal to make products in the EU ready for those conditions by developing a strategy to prolong the lifetime of equipments and to protect consumers. An important part of this proposal is to set common rules promoting the repair of goods, advancing towards the objective of sustainable consumption under the European Green Deal (Figure 01).

Figure 01 – Green Deal policy framework around ESPR (green) and the
ESPR's relationship to the Ecodesign directive (blue). (Source:PRBX/Ecochain)

Developing a repair approach will reduce e-waste and reduce the environmental impact, resulting in significant savings for consumers and all of society. As part of that and similar to how it is for Ecodesign energy consumption labeling, France has proposed the use of a similar label bearing a reparability index to inform consumers about the possibility of repairing a product whilst consumers should have access to repair guidelines.

As proposed in the scope of the project, on December 4, 2023, the European Parliament and Council provisionally agreed an update to the 'ecodesign' rules, aiming to improve various aspects of products throughout their lifecycle to make them more durable, reliable, easier to reuse, upgrade, repair and recycle, use less resources and energy and water.

The proposal covers consumer goods and concerns defects that may occur in them, whether or not still under legal guarantee. The producer will have an obligation to repair goods for five to ten years after they were purchased. Goods for which reparability requirements currently exist include household products such as washing machines, washer-dryers, dishwashers, refrigeration appliances, electronic displays, welding equipment, vacuum cleaners, and servers and data storage. Mobile phones, cordless phones and tablets are also listed in the recent draft, and EV chargers have been considered in the latest discussions. All of these products use power supplies and manufacturers need to keep future legislation and regulations in mind and monitor their evolution.

Why the new Ecodesign rules will matter for the power industry

This introduction may appear to give the impression that it's mostly the consumer segment that will be the subject of future legislation but in fact, inspired by the Ecodesign workgroup a lot of activities are taking place within industry to prolong lifetime and this is where it becomes an interesting area for the power supplies industry.

Regarding consumer applications for power supplies, they are either built-in the equipment and part of the overall system, or external such as USB chargers, and the legislator is working on a classification of the level of reparability in making it environmentally and economically a good idea to repair instead of replace. This is part of the 2024 workgroup that is working in parallel with the industry to define reasonable classifications for the benefit of end users and the environment.

Considering the high levels of integration and current building practices, e.g., the use of sealed plastic products such as external adapters, these may not be classified as repairable but the manufacturers might still have the obligation to guarantee support and service for ten years. Also, for embedded power supplies to listed equipments power supplies, manufacturers will be obliged to guarantee the availability of spare parts during the service period.

At higher power levels, as for the energy consumption Ecodesign regulation, servers and data storage are already included in the proposition, and power supplies manufacturers are working in close cooperation with the European representatives to develop power solutions meeting the reparability needs, but also to guarantee longer life time in operation.

When considering the circular economy, up to 80% of a product's environmental impact can be determined at the design phase. When designing a power supply for a datacenter we always take into consideration energy efficiency, and power designers use the latest technologies such as Wide Bandgap Semiconductors in order to deliver the highest levels of performance. Regarding prolonging lifetime there is a lot of work going on to select components able to keep their original performance for more than ten years in operational conditions, but designers must also include reparability in the mechanical design, which could imply a modular concept easing maintenance, and when end of life arrives, recycling.

For many designers it will be a new way of working but for those used to developing power solutions for refurbishing and system modernization it's nothing really new and a lot of the best practices deployed in this industry are already meeting future Ecodesign regulations.

Before Ecodesign regulation, Reuse, Repair and Prolong Lifetime was already the norm in the railway industry!

Outside of what the Ecodesign is aiming for in consumer segments, many industrial applications require power supplies manufacturers to provide power solutions for refurbishing and systems modernization. Among many, the transport industry and especially the railway are the best examples to illustrate what might be applicable to other segments when it comes to Reuse, Repair and Prolonging Lifetime.

One good example is the French railway state-owned operator, 'Société National des Chemins de Fer (SNCF)', which in September 2023 announced that as part of its commitment to sustainability, SNCF Voyageurs and its Rolling Stock Division are committed to optimizing the use and lifespan of their trains at every stage of their life cycle: mid-life and end-of-life refurbishment to extend their service life and combat obsolescence, and recycling and reuse of spare parts, etc. To achieve that goal, the SNCF has announced the commencement of a major refurbishing project to restore and upgrade 104 high speed trains, 'Trains à Grande Vitesse (TGV)' to "combat obsolescence" (Figure 02).

Figure 02 – SNCF is renovating 104 TGVs with the aim of expanding the current fleet's lifespan. (Source: PRBX/SNCF)

These 104 eligible trainsets have been assessed during the 4th quarter of 2023 and 1st quarter of 2024. A number of criteria will be taken into account when deciding the fate of each trainset, including the condition of the structure of the train set, its metal components, the boiler, the bogies and the electrical installations including power supplies. Based on these criteria, the trainsets will be classified into three categories:

1. Those in perfect condition that will continue to be in service, but will undergo renovation to improve their comfort.
2. Those that require more extensive reliability and renovation work due to their advanced age.
3. Those that will be withdrawn from service due to obsolescence of parts (electronic components or state of the chassis). These written-off trainsets will be used as parts banks as they contain up to 3,000 potentially recoverable components that can be reused to repair other trainsets.

The SNCF refurbishing project very much illustrates within an industrial environment what Ecodesign Reuse, Repair and Prolong Lifetime is aiming for. Reusing parts to reduce waste and optimize resources has been part of the SNCF life cycle process for a long time as rather than buying new, checking and repairing 500,000 TGV spare parts every year represents a saving of half a billion euros a year.

Designing power supplies for refurbishing – New technology paradox

The variety of power supplies required by railway companies when refurbishing trains is very wide and covers from low power modules to high power converters up to hundreds of kilowatts (Figure 03). In a train, many power supplies are embedded within sub-assemblies e.g., LED lighting with built-in power supplies and drivers, but a number of systems require standalone power solutions meeting the latest legislative requirements.

Figure 03 – Power supplies required by railway companies when refurbishing trains is very large and going from
low power modules to high power converters up to hundreds of kilowatts. (Source : PRBX/Shutterstock/ECO LENS)

In general, refurbishing contractors are using referenced part numbers approved by the train manufacturers, and about 80% of the need is available as Commercial off-the-shelf (COTS) from certified power supplies manufacturers, complying with railways standards. However, when refurbishing and modernizing trains that might have been manufactured decades ago, 20% of the power supplies will require extra features, higher power density, lower energy consumption and many more things, often with the need to fit into an existing box that's specific to the application (Figure 04).

Figure 04 – PRBX 110VDC, 10kW Nickel-Cadmium battery charger for refurbishing when replacing Lead-Acid batteries in railway applications.
(Source: PRBX)

When refurbishing or modernizing, the railway industry is following the same pattern as the others, and with the increased demand for higher power density and lower power consumption, power designers are now investigating the implementation of Wide Bandgap (WBG) switching semiconductors, Gallium Nitride (GaN) and Silicon Carbide (SiC).

SiC diodes have been used in railway power supplies for decades, but power switching transistors are relatively new in railway applications. Considering that the lifetime of railway equipment could be greater than 20 years, reliability and supply chain sustainability are a must, and implementing a new technology requires a thorough technical evaluation and the need to ensure that the supply chain is able to guarantee product support for more than 20 years.

In the process of validating a new technology for highly demanding railway applications, the parallel, ongoing process to electrify other transportation and machinery applications is contributing to accelerate market adoption and confidence in WBG and especially SiC. A lot of research has been conducted by the automotive industry to validate WBG technology and the adoption of SiC and GaN in power-trains and battery chargers thus setting a ground base for other segments to adopt the technology.

In high power switching conversion many projects utilize SiC MOSFETs instead of IGBTs and it's worth mentioning the Fraunhofer Institute for Energy Economics and Energy System Technology's MUSiCel research project which by using innovative SiC wide-band-gap semiconductors managed to deliver 250 kW at a switching frequency of 50 kHz with an efficiency across the entire power range exceeding 98 % (at 100 kW, an efficiency of even 98.8% was measured!) (Figure 05). Originally the MUSiCel research project was aimed at the electrification of agricultural and construction machinery, although it can equally apply to railway high power conversion systems and there's no doubt that such research will contribute to the adoption of SiC in future designs.

Figure 05 – SiC 250 kW DC-DC converter developed as part of the Fraunhofer IEE project MUSiCel.
(Source: PRBX/Fraunhofer IEE)

The research of feasibility, reliability and benefits compared to previous technologies is very important, but for railway manufacturers it is crucial that long term supply chain sustainability is guaranteed for the lifetime of the final equipment. As it was for MOSFET technology, WBG semiconductors manufacturers have invested in volume manufacturing facilities or partnerships, but we also see a number of acquisitions e.g., Infineon acquiring GaN Systems, and Renesas acquiring Transphorm. The WBG supply chain for SiC and GaN is now entering a mature phase, thus securing a much needed long term components availability situation.

In conclusion:

To the question: Ecodesign, Reuse, Repair, Prolonging Lifetime and New Technology – Is it the new paradox? The answer is not "Yes" or "No" but as for the railway industry we have given as an example, industry as a whole will have to consider all those aspects when designing new products. The EU Ecodesign is setting a new way of working, and from higher energy efficiency to prolonging the lifetime of final equipments, power electronics will play an important role. One thing is for certain, it is a wonderful opportunity for power designers to explore new frontiers.

About The Author

Chief Marketing and Communications Officer for Powerbox, Patrick Le Fèvre is an experienced, senior marketer and degree-qualified engineer with a 40-year track record of success in power electronics. He has pioneered the marketing of new technologies such as digital power and technical initiatives to reduce energy consumption. Le Fèvre has written and presented numerous white papers and articles at the world's leading international power electronics conferences. These have been published over 450 times in media throughout the world. He is also involved in several environmental forums, sharing his expertise and knowledge of clean energy.


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