eeweb pulse - issue 33, 2012

8/3/2019 EEWeb Pulse - Issue 33, 2012

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Issue February 14, 2012

Dermot O’SheaTaoglas

Electrical Engineering Community

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TA B L E O F C O N T E N T S

Dermot O’Shea 4Taoglas Limited

Navagating the Antenna Challenges 8of Miniaturized TelematicsBYDERMOT O’SHEA

Featured Products 10

Switching FETs and Dead TimeBYPAUL CLARKE WITH EBM-PAPST

Transistors to Turbines 15BYBILLIE JOHNSON WITH WOWE

RTZ - Return to Zero Comic 20

How Taoglas faced the challenges of implementing their high performance antenna system intoa miniature device.

Interview with Dermot O’Shea - Joint Managing Director

Paul Clarke explains why we shouldn’t fear “dead time” when switching FETs.

The story of how one outreach volunteer helped install a wind turbine on a middle school

campus and the positive impact it had on its curriculum.

11



I N T E RV I E W

TaoglasLimited

How did you get intoelectronics/engineering andwhen did you start?I began by studying physicsand mathematics at University College Dublin, and went on to getgraduate degrees in a wide rangeof disciplines from Dublin BusinessSchool, Griffith College Dublin and

Waterford Institute of Technology.My degrees are in the areas of enterprise development, businessstudies, computing and computerhardware design.

After completion of my studies and working in the logistics industry,I decided to travel the world for alittle bit, then came back here toIreland to work in the electronicsindustry. I later went to Taiwan andmet another Irish guy there namedRonan Quinlan. We were of similarminds in terms of wanting to set upour own business, and he had someexperience with electroceramicmaterials, an area that was justtaking off. Electroceramic patchantennas are a very efficient materialfor GPS antennas. In Taiwan there

were some very unique ceramicmaterials that were revolutionary forefficient antennas.

Dermot

O’SheaDermot O’Shea - Joint Managing Director

We have a number of antennasmade of ceramic that have uniqueproperties;

The PA25a and the PA700 aremultiband PCB surface mounted3G and 4G antenna solutions that

provide very high efficienciesto customers requiring highperformance from an embeddedantenna without the need to designa custom solution.

Another antenna, the “Athena”combines a GPS ceramic patch



I N T E RV I E W

antenna, low noise amplifier (LNA),and Front-End SAW filter in one SMTbody, eliminating the requirementfor cables and connectors. It isanother ceramic antenna that isused by M2M manufacturers inautomotive, telematics, trackingand remote monitoring.

I wasn’t really an expert when itcame to antennas; we didn’t really learn about them in university. Butdespite that, we decided to gointo the antenna business with thegoal of providing wireless antennasolutions for mobile and remote

devices that use Global PositioningSystem (GPS) and Global Systemfor Mobile communications (GSM)frequencies to communicate. Westarted the company in 2004, andsince then I’ve become muchmore knowledgeable with regardto antenna technology and havelearned mostly all of what I know now while in the industry.

How many products do youhave today?

We have over 1,000 part numbersin our system now. Every day we dosomething different for a customer,and we are growing progressively larger with our product totalsincreasing all the time. Right now,

we have about 90 products on ourcurrent project list, and averageabout 10 to 15 customer projectsper week. From each of thoseprojects also comes a new productnumber, so we are continuing tosteadily grow.

We not only make GPS antennas— we also supply a range of cellularexternal, embedded and basestation antenna solutions.

Can you tell us more aboutyour antenna designs?

With our product developments, we’re always looking to do somethingbetter. So we’re constantly trying toincorporate different topologies andnew materials. Like I mentionedbefore, ceramics is something that

we began with, and is a technology which is very strong at the moment.Some of our leading antennas aredeveloped with customized raw electroceramic materials inside formore proficient use.

For custom designs, nearly half

the time we spend during thedevelopment process is towardsconducting research. We look atand think about things like how much space we have, the targetperformance for the device,certification required, what typesof antenna topologies we have and

what designs would suit them.

Right now we’re working onan active 4G antenna. We havealready developed 3Gs, but weare constantly looking to improveour designs. And like I said before,those designs are primarily formobile and remote devices thatuse GPS and GSM frequencies tocommunicate.

Compared to when youstarted Taoglas Limited, whatare your capabilities today

regarding characterizationand testing?Today we have an office in Ireland,Taiwan and the United States,each of which contains a lab

with characterization and testingcapabilities. We are now trying toexpand to Mexico, in an effort toattract customers from the Latin

American market. We already havesome basic equipment there, but inthe other three locations we havefull test chambers. This allows us tonot only perform all of the necessary antenna testing, but also the activedevice over the air (OTA) testing.

When we started, we really had noneof these capabilities. But as we’vedeveloped and sold more products,our ability to have these sorts of commodities has increased. Youknow, we’re very much focused onsales and resultant positive change.The equipment we own, we paid for

ourselves. All of the start up funding was used for product development. We work really hard to do everything we can with what we have, and areconstantly trying to improve ourproducts and efficiency.

Are your customers typicallyvery explicit with theircustom design speci cationsregarding things like gain,sensitivity and direction?

As you can imagine, it really dependson the design and the customer. Themore specific designs are usually for higher device performance, ora customer requires a specific speclike gain in a certain direction.

When the design is up to us, we doour best to educate our customersabout the product so they can be ascomfortable as possible with what

they should expect. We’re doing better to convincecustomers to discuss their productdesigns with us first, because if wecan talk to a particular customer atthe beginning of the design, we canbetter determine if we’re the right fitto develop that specific product.



I N T E RV I E W

Do you ever help customersdesign certain antennaswithout manufacturing it forthem? That’s not really part of our business.But we do give our customers all of the product options, and sometimesthe best solution is for us to notdevelop the product after assisting

with the design.

Generally though, when we designantennas for customers, we aren’tonly planning to provide them

with the one antenna as a one off project. We are seeking to forge

partnerships and want to be theantenna provider of choice for allthe requirements of the customer.This not only benefits our own salesand processes but it means thecustomer can avail of unrivalledsupport and our resources fordesign and development are at theirdisposal.

Do you integrate impedancematching circuitry in yourantenna designs, or providedirection for users on what touse on their system?

Again, it depends on the customerand design. We provide guidancefor customers on how to performspecific integrations themselves,and provide information on whatto use on their system. Many customers specifically requestthese sorts of services, and we are

glad to perform them.

Do you perform simulationswith your antennas, or is yourtesting all done in the lab?Simulation is the first stage. Theeffectiveness of antenna simulationhas definitely improved to become

very powerful. The next stage is

prototyping, followed by the laband chamber optimization. We try to start the more traditional way and move on to the lab and testefficiency, which leads to what

we call the active device stage.This stage involves more concretetesting, for example connecting theantenna to the device inside the

For custom designs,nearly half the time

we spend duringthe developmentprocess is towards

conducting research.

chamber and make a call from thebase station simulator to see how the sensivity is in the “pure” un-noisy environment. The reason forthis testing is because no matterhow well the antenna is designed,the active device will always alter itin some way.

These simulation and testingmethods have not only been very successful for us, but have worked

very well for our customers too.

During the simulation process,what kinds of modi cationsare you able to make with theantennas?The simulation process is only amodel and can not be used when

you have a cable and connectorfor example. So you are modifyingthe radiating element seeking the

best return loss and efficiency andlooking at the effects of the devicePCB and battery for example. We

would never go ahead to make anantenna from simulation only, it isonly a guideline and a design tool.

Where do you see TaoglasLimited heading in the nextfew years?

We really want to increase andimprove our services. There is alarge demand for our services,and we can help our customersovercome the challenges they face

when designing these devices.Many of them are under a lot of pressure and don’t have enoughtime to overcome these issuesthemselves, and we can really be of some major assistance.

We recently announced that weare a Sprint M2M CollaborationCenter Partner and a Verizon LTEInnovation Centre partner. Sprint’scollaboration center is a roll-up-

your-sleeves workshop where

partners and enterprises work side-by-side to develop commercially

viable offerings based on M2Mtechnology as well as prepareM2M devices for certification on theSprint Network. We help Sprint’sM2M customers prepare for overthe air (OTA) transmit and receivesensitivity (TRP/TIS) and antennaperformance testing. With Verizon

we are providing 4G antenna and

RF testing and design expertiseto Verizon’s M2M LTE devicemanufacturers. ■



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P R O J E C T

avigatingthe AntennaChallengesof MiniaturizedTelematics Devices

By Dermot O’Shea

Delphi is a global supplier of electronics and technologiesfor automotive and commercial

vehicles. The company deliversreal-world innovations that makeautomotive products smarter andsafer as well as more powerful andefficient.

When Delphi was looking to make anew miniaturized telematics device,it needed an antenna partner that

would not only deliver the bestcellular and GPS performance,but would also help to get product

certification and network approvalsfirst time. Some miniature wirelessdevices are installed underneaththe glove compartment of a carin front of the passenger’s kneeand need to be small enough tofit compactly into the diagnosticsport in the vehicle. Delphi’s new

wireless device had two challenges;

it was less than half the size of a cellphone, but required AT&T networkcertification, which is based on a

cell phone-sized products. Addedto this, the device had stackedPCB boards, which act as a largecapacitor and bring down antennaperformance and efficiency.

Delphi needed an antenna providerfor the small telematics device thatcould meet the challenges anddeliver high antenna efficiency inthese harsh conditions. Delphichose Taoglas the M2M antenna

provider, because of its antennaexpertise, understanding of U.S.network certification processesand because Taoglas could designan antenna and optimize the wholesystem for TIS and TRP testing(receive and transmit sensitivity).“We had integrated antennas insimilar cellular miniaturized wireless

devices before so, we were familiar with the territory,” said DermotO’Shea, director, Taoglas. “This

device however, presented us witha new challenge.” Taoglas workedclosely with the Delphi engineeringteam to figure out the requirementsfor the device and then custom-builta quad-band cellular antenna, thePCS.01 and a custom-tuned GPSactive patch antenna module, the

AP.25H.07.0040A.dn.

“It was difficult to get highperformance inside the device

because it was so small,”commented O’Shea. “When you getdown to that size, the small groundplane leads to efficiency challenges.In order to ensure top antennaperformance, we collaborated withthe Delphi team to optimize the

whole device as a send and receivesystem to minimize the loss from

N

http://www.delphi.com/

http://www.taoglas.com/


http://www.delphi.com/



P R O J E C T

an RF aspect. Devices of this kindpresent an added challenge withtacked boards, which have a hugeimpact on the antenna. It’s probably the most difficult environment toplace an antenna when you considerall the M2M products in the markettoday.”

The PCS.01 was successfully integrated into the telematics

wireless device and passed AT&Tnetwork certification first time. “It

was a fantastic project to work on,”said O’Shea “It presented us withmany challenges, but we met them

head-on and engineered a top-classantenna. Bring on the next antennachallenge.” ■

Figure 1: Toaglas GSM Antenna design.










F E AT U R E D P R O D U C T S

USB 16-bit 5MHz OscilloscopeSaelig Company, Inc. has introduced PS4262, a 2 channel, 5 MHz 16-bit-resolution oscilloscope that includes a built-in low-distortion signalgenerator. PS4262 is a full-featured oscilloscope, with a function/arbitrary

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Digital Thermometers with SPI/3-WireThe MAX31722/MAX31723 digital thermometers and thermostats with

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For applications that require greater temperature resolution, the user can adjust the readout resolution from 9 to 12bits. This is particularly useful in applications where thermal runaway conditions must be detected quickly. Thethermostat has a dedicated open-drain output (active-low TOUT). Two thermostat operating modes, comparatorand interrupt, control thermostat operation based on user-defined nonvolatile trip points (THIGH and TLOW). Bothdevices feature a 1.7V to 3.7V supply rail. For more information, please click here .

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I was looking through some old notes this week andstumbled upon the day I learned about dead time.

No, this is not that fatal moment we all try to ignore;it’s a period of time where switching FETs on and off ineither a Half or Full bridge is critical. So what is it, and

why is the switching of FETs so important?

When digital meets analogue circuits, it is always fungetting the results you want and Half and Full bridges areno exception. Although I’ll be looking at these particularcircuits, it’s fair to say the same ideas will also be usefulfor switching any device, such as turning a FET on andoff, with accurate timing and control.

Below, I have set out the basics of one side of a bridge,but with some components removed so we can look atthe key features alone. (Figure 1)

The circuit works by generating a square wave from theHI and LO outputs in the opposite phase. This, in theory,means that only one device is on at a time and that point‘A’ will go between 0 volts and +V. You will see that thereare two resistors connected to the gates of the FETs.These are specified by the datasheet as required. They

limit the current that flows between the driver IC and theFETs gate. The gate in these devices contains a smallcapacitor that is just part of the function of the FET. So

when the gate voltage ( Vgs ) swings between 0 and, say 15 volts, this capacitor needs to charge up. Then it needsto discharge when the gate goes back to 0 volts. Thedriver ICs can switch rather high instantaneous currents,

Figure 1: Driver IC Circuit

A

I

4R7HI

LO

COM

0 Volts

4R7

+ V

Switching FETs

& Dead Time

Paul Clarke Electronics Design Engineer



T E C H N I C A L A RT I C L E

but the resistor is there to limit this. I’ve also added zenordiodes, which is good practice as this protects the gate

voltage from going over the switching level (in this case15 volts) or generating a negative voltage below -0.5.Lastly, I have added an inductor (I) which is not really a fitted device, but will represent the PCB inductancebetween the bottom FET and the 0 volt reference of thedriver IC (in this example the driver side is connectedseparately to the bottom of the FET, but is not alwaysavailable in ICs of this type).

So what we should see if nothing is connected at ‘A’ isonly a transition of voltage and no current passing fromtop to bottom. However, we have two RC circuits formedby the capacitor in the FETs and the series resistors thatare affecting the gates of the FETs. What we see is one

device slowly switching on as the other slowly switchesoff. At a mid point, the FETs are both partly switched onand current will flow. In the circuit I was testing at thetime, I had 400Vdc across the bridge and was getting 30amps through the FETs for around 1nS—not good. Thiscauses more issues than simply a large current surgeand EMC. The large current in the PCB and my invisibleinductor causes a voltage to appear at the source of thebottom FET. This lifts the COM connection, and in thisdevice has the effect of starting to switch the FET off again (Vgs reduces). You will also notice ringing noise inthe circuit as the inductance starts to resonate.

Figure 2: New FET gate circuit

to 22R. Then to get a really quick switch off time I use abypass diode that allows the driver IC to quickly groundthe gate of the FET. In some cases you may still want asmall resistor, for example, 1R in series with this diodeif the gate currents are large, but the diode alone willnormally do the job. In my circuit this reduced the currentto less than 1 amp at the crossover and was acceptableat the time.

22R

The old way of fixing this is to generate some deadtime when the devices are both switched off enough,preventing large current surges. This was done by changing the circuit that feeds the FET. First, we wantto slow down the charging of the FET when switching iton by increasing the resistance—in this case from 4R7

Dead Time

This period of time, as I said, is called the “dead time”and allows for the reduction of this short circuit effect thathappens in these circuits. However, times have evolvedand dead time control is now built into driver ICs andeven microcontrollers. It would not be too hard to seethat in the above circuit, if the HI and LO signals have ashort pause between transitions allowing control of thetiming of the gates and the switching of the FETs.

Dead time is not symmetrical, and this can be seen in

modern dead time control devices. The circuit above will have different current surges when going from highto low and low to high. So the new devices use a pre andpost-timer that can be separately configured. Below youcan see a typical timing arrangement for this taken froma Microchip controller.

It’s easy to see the original signal (PWM Generator) thatfeeds the dead time control circuit. With a time set to zero,

Figure 3: Dead Time




the high and low sides switch together. Then adjustingthese pre and post-times allows for asymmetric dead

times.This allows for more efficient control and will allow youto reduce losses in circuit designs. You are also reducingnoise that can affect your EMC results. Dead time andcontrolling FET gate switching can make significantimprovements and modern devices are allowingincreasingly better control.

Figure 4: Pre and Post Timing

PWM Generator

PWMxHy

PWMxLy

PWMxHy

PWMxLy

Time selected by DTSxA bit (A or B) Time selected by DTSxl bit (A or B)

Non-zerodead time

Dead time = 0

About the Author

Paul Clarke is a digital electronics engineer with strongsoftware skills in assembly and C for embeddedsystems. At ebm-papst, he develops embeddedelectronics for thermal management control solutionsfor the air movement industry. He is responsible for theentire development cycle, from working with customerson requirement specifications to circuit and PCB design,developing the software, release of drawings, andproduction support. ■

EEWebElectrical Engineering Community

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6A Digital Synchronous Step-Down DC/DC Converterwith Auto Compensation

ZL2101The ZL2101 is a 6A digital converter with auto compensation andintegrated power management that combines an integratedsynchronous step-down DC/DC converter with key powermanagement functions in a small package, resulting in a flexibleand integrated solution.

The ZL2101 can provide an output voltage from 0.54V to 5.5V(with margin) from an input voltage between 4.5V and 14V.Internal low r DS(ON) synchronous power MOSFETs enable theZL2101 to deliver continuous loads up to 6A wi th high efficiency.An internal Schottky bootstrap diode reduces discretecomponent count. The ZL2101 also supports phase spreading toreduce system input capacitance.

Power management features such as digital soft-start delay andramp, sequencing, tracking, and margining can be configured bysimple pin-strapping or through an on-chip serial port. TheZL2101 uses the PMBus™ protocol for communication with ahost controller and the Digital-DC bus for interoperabilitybetween other Zilker Labs devices.

Features• Integrated MOSFET Switches

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Applications• Telecom, Networking, Storage equipment

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Related Literature• AN2010 “Thermal and Layout Guidelines for Digital-DC™

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FIGURE 1. ZL2101 EFFICIENCY

40

50

60

70

80

90

100

IOUT (A)

E F F I C I E N C Y ( % )

0.0 1.0 2.0 3.0 4.0 5.0 6.0

VIN = 12Vf SW = 200kHzL = 6µH

VOUT = 3.3V

January 23, 2012

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Introduction

Many tech companies sponsor outreach initiativesranging from robotics programs to science andengineering fairs to one-time field trips. Motives forsuch sponsorships vary as widely as the examples of outreach. Companies may be leveraging the PR value of such programs, utilizing a tax break, or have a genuineinterest in planting seeds for the future tech workforce.Kids—our next generation of scientists and engineers—can reap the benefits.

Sometimes the volunteer efforts of individual engineers,technicians and other STEM (Science, Technology,Engineering, and Math) proponents can be just as

valuable at a grassroots level as a sweeping corporateendorsement. And, for the volunteer, opportunities existto dive into the depths of technical content or simply leadstudents through a few basics.

This story traces how my involvement in a middle schoolmath program led to the installation of a residential windturbine on the school’s campus and the integration of technically rich renewable energy education into itscurriculum.

Background

I spend my days nestled in a cubicle laying out million-gate ASICs for ON Semiconductor. I love the visual aspectof my job in getting to see what the IO, memories, IP androadways of a chip will look like before it is manufactured,but it’s good for me to think outside of the cubicle. It’seven better to get outside of it once in a while. My favoritehobby loosely tied to my engineering career is coachinga middle school math club, MATHCOUNTS® , at thePocatello Community Charter School (PCCS).

My job as an engineer established an immediatecredibility with the students, parents and educatorsat PCCS when I first began working with their

MATHCOUNTS club 11 years ago. Unfortunately, I soonfound out I had the classroom management skills of abrick. I didn’t have a handle on different learning stylesor the intricacies of leading project-based explorations.

When I think I’ve got a grasp of what works with kids,I have conversations with their teachers that have merevamping lessons and teaching strategies. To apply aterm from our industry, this school is on the “bleedingedge” of educational reform. Like engineers are always

Transitorsto Turbines:

Billie Johnson Physical Design Engineer

Outreach with Substance

V cc

V out

V in

V cc

V out

V in

V cc

V out

V in

http://www.mathcounts.org/

http://www.mathcounts.org/




improving flows, methodologies and design techniques,teachers are continuously improving teaching methodsbased on research regarding the best possible practices.PCCS follows an Expeditionary Learning curriculummodel. My math club has become much more successfulas I familiarized myself with Expeditionary Learning andincorporated more real-world examples in our practices.

The Allure of Wind Power

A few years ago, just as we were wrapping up ourMATHCOUNTS season, the Women of Wind Energy (WoWE) sponsored an ad in an IEEE newsletter forscholarships to an annual WINDPOWER conference. Inthe same week, the nearby Idaho National Laboratory (INL) helped install a wind turbine on a high schoolcampus in southern Idaho. Both of these piqued my interest and prompted some hearty internet research.I uncovered a Department of Energy initiative called

Wind for Schools and learned that a few of the flagshipmembers of WoWE had ties to this program. The moreI learned about the program and WoWE’s commitmentto wind energy education, the more clear it became thatPCCS was a perfect candidate and that I had an entirenetwork out there that could help.

The program was running in six states at the time andprovided a model for installing a residential wind turbine(2.7kW) and sensor on school campuses. Web-based software is included, which allows students to see whattheir own turbine is doing and cprovides a comparisonto turbines at other schools across the country. I wrote afew grants, made a few phone calls, and (fast-forward 18months ) PCCS was the first entity in the city of Pocatello,Idaho to tackle the permitting process needed to installa residential wind turbine. They also have a 1.1kW solarpanel to make two authentic real-world projects to draw upon for loads of math and science investigations.

Installation Process

The PCCS student council was invited to help assemblethe turbine and see all that happens on installation day.The kids attached the blades to the rotor, transportedthe entire blade assembly to the base of the tower, andthreaded the bolts of the tower’s base. An engineeringstudent from Boise State University (BSU), who receivedscholarship funding also through the Wind for Schoolsprogram, was on site guiding the kids through everythingalong with engineers from BSU and INL.

Figure 1: Students assemble a wind turbine at Pocatello Community Charter School

http://elschools.org/

http://www.womenofwindenergy.org/

http://www.windpoweringamerica.gov/schools_wfs_project.asp

http://wind-for-schools.caesenergy.org/wind-for-schools/Welcome.html

http://wind-for-schools.caesenergy.org/wind-for-schools/Welcome.html

http://www.windpoweringamerica.gov/schools_wfs_project.asp

http://www.womenofwindenergy.org/

http://elschools.org/




The entire process was captured in a slideshow andis available on YouTube. The students who helped

with the installation are now in high school, but each year that the middle school classes embark upon theirrenewable energy expedition, teachers show the videoto demonstrate how their wind turbine came to be.

The staff and administration at the school deserve allof the credit for leveraging education opportunitiesavailable with an on-site wind turbine. They haveassembled the content and developed hands-onprojects that augment their school’s renewable energy nicely. Part of their course work has the students buildtheir own miniature wind turbines and test them with box fans. I have an opportunity each year to listen to the kidsexplain their blade designs and configurations when

they present their experiments and findings. It’s easy toimagine many of these young people working alongsideme in a decade or so.

ON Semiconductor Associations

I used to be able to kick off each MATHCOUNTS seasontalking about how chips I’ve worked on are in cell phones,printers, medical devices, and top-secret military andaerospace applications. Cell phones are “so yesterday”,and I’ve found that just hearing about applications isn’tgood enough anymore for these kids. They expect to seeand experience it.

While my main goal is to enhance their performance andcomprehension in our math club, I naturally like to giveas many plugs as I can for a career in engineering. It’sdifficult to get them excited about electrical engineeringthrough ASICs alone because they just aren’t flashy –all of the excitement happens beneath the lid. Circuit

boards are nebulous and confusing for 6-8th graders, butthe wind turbine in their backyard and the solar panel onthe front of their school offer great visuals and a segue

way for what my company and I do.

All students at the school, from kindergarten through 8thgrade, understand basic information about wind energy and solar power. They know how wind is created, how sunlight is converted to electricity, the main parts of aturbine, and how the turbine utilizes wind to createelectricity. The 7th and 8th graders tackle a more in-depthstudy on renewable energy, so they have an even morerobust foundation of knowledge. Now, instead of kickingoff MATHCOUNTS season just talking, I ask them totell me what they know about their school’s turbine and

wind energy. After they have exuberantly and beautifully

covered just about everything, they enjoy hearing abouthow the factory in their own community designs andmanufactures chips that appear throughout the processof harnessing renewable energies.

I use illustrations (1) to demonstrate where ONSemiconductor technology can be found in a gridsystem, including their own school’s smart meter. Iexplain that the inverter is actually contained withinthe nacelle of their turbine, but that most systems havea standalone one. My personal cool factor gets a littleboost when they learn that ON Semiconductor develops

power management components that control, convert,protect and monitor the supply of power in systems justlike theirs.

My most humorous and enlightening experience came when explaining the RF sensors atop the turbine thatcommunicate wind speeds and energy data. Naturally,

Figure 2: Students build miniature wind turbines

http://www.youtube.com/watch?v=ODTl3ST-_WI

http://www.youtube.com/watch?v=ODTl3ST-_WI




one of the kids asked what “RF” stands for. I attempteda little side-splitting engineer humor and replied, “RealFast.” Of course, since none of them knew it was really “Radio Frequency”, there was no laughter amidst my pre-teen audience (I know a few of them will use thatline in one of their classes later in life and score a few extra points with their professor). It’s normal for a littlechatter to surface while they work their weekly problems,and shortly after that I overheard one of the kids tell hisbuddy, “Yeah, whatever. I’m already done because I’mRF. That’s ‘Real Fast,’ which obviously you are not.” Itcracks me up when they engage in math smack talk, butit’s even better when they articulate technical puns at thisage.

Conclusion

Many companies, including mine, are committed toeducational outreach initiatives. It can be tricky, both at thecorporate and personal levels, to support opportunitiesthat have the most bang for the buck, so to speak. Whenoutreach addresses teaching standards, it is even more

valuable in the eyes of teachers and administrators.

Experiences like field trips or robotics programs areindisputably valuable, but when all kids get to see and

understand examples of engineering every day ontheir campus, they have an authentic ownership andinvestment in learning about their wind turbine.

Our wind turbine project has led to one child excitedly

telling me about how her family was stuck at a railroadcrossing when utility scale wind turbine blades wentthrough town. She seized upon this captive audienceand informed the car load about how the cranes will

work with them when they arrive at the construction site. Another boy talked about his family’s frustration during around of weekend disc golf when the wind kept divertingtheir discs, but he knew it meant good things for hisschool’s net metering.

Wind energy in particular is visually captivating, new to the mainstream scene, and popular. Also, at its mostrudimentary level, its mechanical work-to-electricalenergy concepts are the same for a classroom kit or autility scale turbine. It has been a great vessel for mathand science education. I encourage you to explore any outreach opportunities through your company or in yourcommunity. It’s fun, good for our profession, and greatfor the soul.

Grid-connected Systems

Wind Turbine

Inverter

Meter

AC

Figure 3: ON Semiconductor technologies in wind energy systems




Acknowledgements

The Wind for Schools program and Idaho’s Wind Application Center representatives at Boise StateUniversity were instrumental throughout permitting and

construction. The Idaho National Laboratory (INL) andthe Center for Advanced Energy Studies (CAES) createdand hosted a database to allow turbine data sharing forall Wind for Schools projects nationwide. Membersof the Women of Wind Energy from across the country contributed wind turbine calendars, children’s books,educational materials and consultation. With increasingcuts to education funding, this project would not havebeen possible without the monetary and labor donationsof local and state businesses, parents, teachers, andmembers of the Pocatello community. The wind turbinekits used at the Pocatello Community Charter School

were purchased through KidWind® and are available to

anyone who wants to play with the power of the wind.

References

(1) http://www.windpoweringamerica.gov/pdfs/small_ wind/small_wind_guide.pdf.

About the Author

Billie Johnson is a Physical Design Engineer at ONSemiconductor. Her work experience spans test, design,technical marketing and layout, and she holds a B.S. inEngineering and an MBA from Idaho State University inPocatello, Idaho. She has participated in numerous K-12math and engineering outreach programs throughout hercareer including MATHCOUNTS ®,FIRST®LEGO®League (FLL®) , Wind for Schools and Introduce a Girlto Engineering Day. ■

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http://www.kidwind.org/

http://www.windpoweringamerica.gov/pdfs/small_wind/small_wind_guide.pdf






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