HOW2POWER TODAY

ISSUE: September 2022

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IN THIS ISSUE:

» Inverter With Modified PLL Control Transitions Seamlessly Between On- And Off-Grid Operation

» Designing An Open-Source Power Inverter (Part 7): Kilowatt Inverter Magnetics

» Focus On Magnetics:
Roshen’s Models Offer An Advanced Approach To Modeling Core Losses

» Book Review:
A Very Useful Reference For Power Supply Designers

» Industry Event: NSREC

» New Power Products

» More Industry Events

» Other Top Power News

The IEEE Energy Conversion Congress & Exposition (ECCE 2022) is now less than a month away. Although the conference is well established as it enters its 14th year, there are many aspects to this year’s program (October 9-13) that will make it new and exciting for those who make the trip to Huntington Place in downtown Detroit. For instance, this year the opportunities to learn about developments relating to electric vehicles will be heightened. For those who have not yet made plans to attend ECCE 2022, but are within driving distance, consider the free options available to working engineers. On Monday, October 10, you can attend the plenary talks in the morning (8:30- 11:15) and then visit the expo hall in the evening (4:00-7:30). You can also tour the expo hall on Tuesday, Oct 11, from 10:30 am to 5:00 pm. During both sessions, you’ll be able to view displays and demos from approximately 50 exhibitors showcasing the latest design tools, instruments, components and materials for development of power electronics, electric machines and their applications. But there’s a special treat this year in that you’ll see the latest EVs from GM, Ford and Stellantis, and have opportunities to speak with their engineers. Food and drinks will be served during both exhibition sessions. In addition to attracting engineers from industry, ECCE’s large conference program has always drawn many engineering students. This year, for the first time, ECCE will take advantage of their presence by hosting a job fair for students on Tuesday morning prior to the opening of the exhibition. Beyond these free options, there’s much more to the ECCE program, so if you attend, consider registering for the paid elements like the tutorials, technical and special sessions, and the local technical tours. See the website for more details, and while visiting the exhibition please stop by the How2Power.com booth (#219) and say hello!

HOW2POWER EXCLUSIVE DESIGN ARTICLES

Inverter With Modified PLL Control Transitions Seamlessly Between On- And Off-Grid Operation

by Basil Issac, Eram Power Electronics, Bangalore, India

The phase, amplitude and frequency of the utility grid are critical information for the operation of grid-connected inverters. In such applications, an accurate and fast detection of the phase angle of the utility voltage is essential to assure correct generation of the reference signals for synchronizing operation of the inverters with the grid. Another key element in these applications is the phase-locked loop (PLL) structure. In a grid-connected system, the purpose of the PLL is to synchronize the inverter voltage phase angle with the angle of the grid voltage, in order to obtain zero phase shift and frequency difference between the grid voltage and the inverter. In this article, an enhanced PLL-based control technique for a grid-connected inverter is introduced and simulated using MATLAB software. Read the article…

The technique presented here uses an
internal robust droop controller with
additional voltage feedback and an
external PLL configuration to synchronize
the inverter with the grid.

This saturation model plots the
fractional saturation (k_sat) curves for
various materials approximated
around k_sat = 0.5, a typical minimum
operating-point for power inductors.

Designing An Open-Source Power Inverter (Part 7): Kilowatt Inverter Magnetics

by Dennis Feucht, Innovatia Laboratories, Cayo, Belize

The last two parts of this series, described the design of circuitry for the inverter stage (INV401) of the 1.2-kW Volksinverter design. This part shows how to design the output inductor for this stage. Specifically, it is a coupled inductor having two identical windings, and forms an LC filter with an output capacitor. This coupled inductor rejects noise and prevents overcurrent of the output waveform. This design begins with a set of min and max constraints on the range of inductance values for this component. From there a saturation model derived by the author enables us to identify the most suitable core material based on cost and size. Core material selection then leads to details of core size selection and winding design including number of turns, wire size and wire bundling, number of layers and wire length. Read the article…

FOCUS ON MAGNETICS       
Sponsored by Payton Planar Magnetics
A monthly column presenting information on power magnetics design, products, or related technology

Roshen’s Models Offer An Advanced Approach To Modeling Core Losses

by Alfonso Martínez, AutoPlanar, Madrid, Spain

Because of the vicissitudes of my professional life, I have ended up in a curious position where my duties include finding, understanding, implementing, and comparing models for magnetic components. And along this path I came across the work of Waseem Roshen. What did he model, you may wonder? Core losses like Steinmetz? Winding losses like Dowell? Well, both, which made it really easy for me to admire him. Since this article was intended to be about core losses, we will save his work on winding losses for another occasion and focus here on explaining how Roshen models the three sources of core losses—hysteresis, classical eddy current and excess eddy current losses. We’ll also discuss how these models compare with Steinmetz-derived models. Read the full article…

BOOK REVIEW

A Very Useful Reference For Power Supply Designers

Switching Power Supply Design, A Concise Practical Handbook, Lazar Rozenblat, ISBN 9798757654942, paperback and Kindle format, 109 pages, 2021, $9.99.

Reviewed by Kevin Parmenter, Contributor, How2Power.com

When I review technical books, I typically ask myself whether the work in question is something I would use routinely as an engineer. Switching Power Supply Design, A Concise Practical Handbook is just that. Its everyday usefulness lies as much in what it is not as in what it is: It is neither a cookbook, an instructional text nor an academic work to teach theoretical topics to students. As its title implies, this is a concise and practical handbook. Read the full story…

INDUSTRY EVENT

NSREC Notes: Exhibitors Showcase Latest Reference Designs Along With Progress In Rad-Tolerant And Rad-Hard Power Components

by David G. Morrison, Editor, How2Power.com

After two years of virtual conferencing, the Nuclear & Space Radiation Effects Conference (NSREC 2022) returned to in-person, holding its conference and exhibition July 18-22 in Provo, Utah. The industrial exhibits hosted 49 companies occupying a total of 55 booths with manufacturers of rad-hard power semiconductors and power modules well represented as usual. Among the power product sightings in this year’s exhibition, power IC vendors continued to showcase their power management reference designs for the latest space-grade FPGAs as well as eval boards for rad-hard or rad-tolerant power semiconductors and ICs. And while power IC makers were busy the past few years introducing new power supply controllers and voltage regulators, at this year’s NSREC, their news was more in the way of updates on the status of those previously introduced parts or parts still in development. Nevertheless, some IC and module suppliers did share information on new power supply controllers, point-of-load regulators (POLs) and isolated dc-dc converters.

Read the full story…

  — POWER PRODUCTS IN 3 IMAGES OR LESS

MORE INDUSTRY EVENTS

Wide-Bandgap Experts Will Gather Again At WiPDA

The organizing committee for the 9th Annual IEEE/PMSA Workshop on Wide Bandgap Power Devices and Applications (WiPDA) is looking forward to returning to an in-person event from November 7–9, 2022 at the Sonesta Redondo Beach and Marina in Redondo Beach, California. The workshop is sponsored by the IEEE Power Electronics Society (PELS), the Power Supply Manufacturer’s Association (PMSA), and the IEEE Electron Devices Society (EDS) and provides engineers and scientists with opportunities to share their expertise in wide bandgap (WBG) semiconductor technology. WiPDA provides a forum for device scientists, circuit designers, and application engineers from the Power Electronics and Electron Devices societies to share technology updates, research findings, experience and potential applications.

Read the full story…

PCIM Asia 2022 Moves To October

In light of recent developments concerning the pandemic in Shanghai, PCIM Asia will now be held from October 26–28, 2022 in Hall E1 at the Shanghai New International Expo Centre. The show will continue to provide a platform for exchanging ideas, showcasing technologies and expanding business networks.

For more details…

OTHER TOP POWER NEWS

A white paper by Ron Demcko and Slavomir Pala of Kyocera-AVX discusses the use of aluminum electrolytic capacitors to improve power quality in BLDC motor controllers and drives.  

Power America’s annual Wide Bandgap Devices and Applications Short Course, which will be held virtually on October 25 to 27, will enable SiC and GaN power electronics professionals to incorporate this technology into products and systems and fully utilize its benefits.

Those wishing to register for RADECS 2022 have until Monday September 19, 2022. The conference will be held October 3-7 in Venice.