EEWeb Pulse - Issue 31, 2012

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Interview with Michael Hoff; More on Software Clock Handling; Measurement Uncertainty and CISPR 11; RTZ - Return to Zero Comic

Transcript of EEWeb Pulse - Issue 31, 2012



Issue 31 January 31, 2012

Michael HoffA123 SystemsElectrical Engineering Community

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TA B L E O F C O N T E N T SMichael HoffA123 SYSTEMSInterview with Michael Hoff - Director of Applications Engineering

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Featured Products More on Software Clock HandlingA look at global clock recovery, distributed clock synchronization and event synchronization.


Measurement Uncertainty and CISPR 11BY RYAN URNESS WITH LS RESEARCHConsidering measurement uncertainty in the fourth edition of CISPR 11.

RTZ - Return to Zero Comic

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MichaelHoff A123 SystemsHow did you get into electronics/engineering and when did you start? I got started in electronics when I was in elementary school working on my toy train set. It started as a single loop, then I expanded it over time to have multiple loops with switches, switchbacks, elevated sections, mountains, tunnels and towns. I wired a control panel for town and street lighting and track control. After nearly electrocuting myself more than once, I knew that this field was for me. But seriously, the ability to enable motion, vision and action with electrical power, even way back then, gripped my imagination with thoughts, dreams and ideas that I can still remember now. Before seventh grade, I took out every book in the local library on electronics to slowly try to understand things like the difference between current and voltage, a relay from a tube, and an NPN from a PNP To my parents chagrin, I . took apart every broken appliance we had in the house to see how the electronics worked. Going into college, I briefly considered mechanical engineering, but in the end, I was hooked by the idea and mysteries of harnessing the mathematical properties of those tiny electrons. Can you tell us about your work history/journey to becoming the Director of Applications Engineering at A123 Systems, Inc.? I was the second engineer hired at American Power Conversion back in the 1980s just before the PC boom took hold of the world. Along with the rest of the company, I learned what it takes to grow from a startup company under leaking roofs and under-sized warehouses to a multi-billion dollar industry player with multiple global factories and engineering centers. I morphed from a junior engineering assistant to lead the advanced product research center of the largest division there.Michael Hoff - Director of Applications Engineering; Energy Solutions Group



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INTERVIEWIn that capacity, I directed our team to investigate alternative energy storage media like advanced leadacid, NiMH, lithium ion, fuel cells, flywheels, capacitors and even plasma toroids. When I stumbled on A123 with another possible battery technology, I took a visit to see if they had the capabilities that they promised. One of the APC founders and I asked them some hard questions, and we were satisfied that they had the best battery we had ever seen. Soon after, Dave Vieau, A123s CEO, asked me to help them build their systems capability because they only had cell and electrochemical design expertise in-house at the time. I joined A123 more than five years ago to launch the systems engineering group, design several products and product lines, build the safety and compliance group, and now head the applications engineering teamthe AE team. In this latter role, we take the customers needs and desires and turn them into a product concept complete with estimated costs, budget, resources and timelines from contract to fulfillment. The exposure to all kinds of markets, applications, geographies and customers makes the job very interesting. For example, we might be designing and building a small 4-cell pack for a roving robot, while at the same time imagineering a large grid-based farm of battery containers containing half a million cells. Do you have any tricks up your sleeve? I love to tell young engineers about the conundrum faced by both an engineer and a scientist in a long corridor. They are asked to split the distance with each step in order to reach the prize at the other end of the corridor. The brilliant scientist quickly realizes that the objective will never be achievable because his velocity converges to zero. But the engineer, after mulling on it for a moment (like engineers like to do), decided that for all practical purposes, she can get close enough to reach out and grab the prize and take it home. I use this principle to accomplish things that most people would give up on before they even attempt it. I consider the most important things first, and worry about the details when I have to. What has been your favorite project? My favorite projects are ones where I have broad involvement. At many large companies, engineers involvement is compartmentalized according to their job title. This can limit their exposure to, and passion for, projects to which they contribute. As the lead engineer on the Smart-UPS 400 project at APC I was involved with all aspects of the project. I conceived the physical shape, and designed the circuits, PCB, magnetics, ASICs and mechanical hardware. Then, after building and programming the production test fixtures, and releasing it to production, I travelled to Europe to announce it at a sales show in Hanover, Germany. At A123, I also contribute in multiple aspects of the programs in which Im involved. Here engineers are expected to contribute in multiple disciplines of the design, not just those defined by their job titles. The opportunity to gain this broad experience not only benefits the company, but the individual as well. The ownership and pride that one feels at A123 from contributing to a products success is second to none. Thats the beauty of this place: When you rise to the challenge, you are rewarded with even more challenges! Do you have any note-worthy engineering experiences? I have my hands in four released patents, and three more in the works. I have spoken at four major conferences and written several papers for the public. I have released multiple products from UPS to battery packs, but one of the proudest moments in my career occurred recently when a young studentnot sure where he wanted to end uphappened to intern for me. After his time here, he wrote and thanked me for my time and said that because of his intern experience with me he was going to settle down and target an engineering degree for his college years. What are you currently working on? Currently my team and I have just finished imagineering a roughly 10MW, 4MWh energy storage system that will be used to enable the installation of a large wind farm on a small island power grid. Because the wind farm could produce a large percentage of the islands power needs in one quick


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INTERVIEWwind gust, one can imagine how a blustery day would affect the power quality for all the nearby customers. Their line voltage would swing rapidly in one direction or another as the wind stops and starts, and the small islands traditional fuel-based power generators would try in vain to control their output in response to the rapidly fluctuating power influxes. An A123 energy storage system can absorb the power influxes and gradually transition the turbines power on or off the grid to allow the traditional fossilbased generation time to respond to the changing needs. The energy storage system acts like a big shock absorber on the grid system to keep it from bouncing around like a big network of interconnected springs. Without our system, our customers would not be able to install the wind turbine on the island to save their rate payers millions of dollars and protect the environment by minimizing vast quantities of wasted carbon in the atmosphere. What are your main goals and responsibilities as the Director of Applications Engineering? Even though we are a mediumsized company, in many ways we still act like a small one. As director of my department, I strive to meet our customer expectations and schedules, but more often than not I end up drawing one-line diagrams, simple mechanical layouts, filling out the spreadsheets, writing specifications, and reviewing the same from the rest of the team. That often means working late hours with the team and getting in early to do the rest of the stuff that has to get done. My goal as a manager has always been to make everyone know they are a vital part of the team, and to make the team look like it contains more people than it really does. such prototypes to test on its famed formidable wall of power. We designed the circuits, mechanics, and firmware, and basically printed the prototypes in our fast prototyping