Saturday, October 13, 2012

Porsche Club Autocross #2

Our Porsche club held the second autocross event at the Santa Maria airport track on October 6, 2012.  You can find the details about the track and the first event here.  I didn't bring my 914 down because it's a long haul on the trailer and I didn't know if there was a plug available for a top-off charge between sessions.  I found out while I was there that there is a plug at the aerial firefighting station and perhaps I could get a plug at the Jet Center, so I'll think about it for next time.

The track had a different layout this time, with a full lap followed by a half-second lap which crossed over the return run to the finishing straight.  With two cars on the track on each run, we joked that the crossing point was sponsored by Vintage Auto Body.  Luckily, there were no accidents, but several cars forgot to make the turn on the second lap and were red flagged.

Here's a shot of the pit area, I think there were 40 - 50 cars in attendance, a lot of Porsches but also VWs, Subarus, Corvettes and others

There were 3 groups and while your car was not running you were assigned cone or flagging duty.  Each group got 4 runs in the morning, and 3 runs in the afternoon as we were running out of time.  This is the starting grid.

This is the very far end of the track with the big 180.  This was my position as background-checked-and-certified-airport-TSA-security-for-the-day.  I wanted to take a picture of my badge but didn't want to risk ending up in Guantanamo Bay.

Here's video of the most aggressive car making this turn, a bright red Turbo.

There were a blue and yellow 914, had to get a video of the blue one.

We had some spectators from the Jet Center and aerial firefighting station.

Saturday, September 29, 2012

EVCCON 2012 Day 3

After the drag racing, autocrossing, dynamometer testing and socializing, attendees were a bit thin in the seats first thing on Saturday morning!

We kicked off with a roundtable discussion about electric boats with Anne Kloppenborg, Bill Denning, Jack and Jeff Southern.

Anne has completed a 1970s Glastron crusing/speed boat conversion project, in the Netherlands.  It's great for both meandering around Amsterdam's harbor and canals and water skiing.  He used Lithium batteries obviously and kept the Volvo-Penta stern drive via a custom-machined adapter plate.  He's done extensive testing on energy usage at different speeds and at city speed he is pulling 1.3KW and can cruise for 20 hours on his battery pack, and in open water, peak power output is when he comes up on plane and then when on plane drops down to 41 KW.  At top speed, it's pulling 86 KW, so a little more speed takes a great deal of additional power.  Boats have a different driving style than cars, as they tend to go at slow speed to get out of the marina, then at constant high speed for extended periods of time, then slow again when you get to your destination.  This may have a detrimental effect on EV-targeted motors unless sufficient cooling is implemented and a water-cooled motor would be natural in this application.  Anne is now working on converting a 1950s Ray Wright Delta speedboat from a British company that made Spitfires in WW II.  It's very small and fast!

Bill then spoke about a 40' boat project he's starting, making it out of Magnesium Oxide board, which is cheap and 4 times the strength of concrete..  He wants to do The Great Loop.

Jeff Southern then spoke about his history converting a dozen 5hp outboard motors to electric drive.  Jack wants to convert an Aristocraft 14' speedboat and Jeff went to visit their factory outside Atlanta.  Going with an electric boat will help as more and more restrictions are being placed on gas motor noise and pollution on lakes.  Anne said that the Amsterdam is forcing tour companies to switch their boats from diesel over to electric.  Jack and Anne believe that boat pricing is such that you can successfully put an electric drivetrain in a boat and make it still in the price range that people would expect, and the effective  fuel cost is significantly lower.

Dave Hrivnak asked about the effects of salt water on electrical equipment and electrical safety issues with all of that water around.  Nobody had any experience with salt water effects, but Anne said he got zapped when a wave came over his boat and he touched a wire that hadn't been properly mounted.  Jack said that electrical safety on the water is a big issue and more effort needs to be put into waterproof packaging the components.  Anne said one of his sub-packs got completely submerged in fresh water and there were no issues.  Jeff said that he has seen no corrosion in an extensive fresh water environment.  Jeff said electric boats work well in very cold temperatures when gasoline engines have a hard time starting.

George Hamstra from NetGain made an announcement about a new product, under development for 5 years.  He has partnered with a large AC motor manufacturer, which supplies motors to along others Kia, Hyundai and Mercedes and trains, to bring 3 AC motors into the NetGain family.  First is a 15KW-30KW 9,000 rpm air-cooled motor targeted to outboard motors.  Next is a 30-60KW 9,000 rpm and 50-100KW 12,000 rpm liquid cooled motors.  The controller they're partnering with the motors is a called ICPU which includes charger and J1772 plug and CANBus data connection.  Pricing will be targeted at the same price as a current motor and controller.  George had the unit under a black blanket so I will take a picture and put it here when the session is over.  Update: Here they are, the motor is smaller than my WarP 9, and the controller is mounted on a huge finned heatsink.  Not much detail yet, nothing on their web site.

Next up was a panel discussion on Driving the EV Business, with Jack, Sebastien Bourgois from Evnetics, George Hamstra from NetGain and Michael Bream from EV West.

George kicked off with a "presentation more dangerous than high voltage because it's about money, so use your common sense."  The keys to success are hard work, dedication, knowledge (why we are all here at the show), drive, attitude, timing, luck (and making your own luck).  The dirty work is inventory, AP, AR, balance sheet, customers (questions, phone calls and problems) and product documentation.  You will need to do quarterly reports for potential business partners and banks.  Steps to success are choosing the right business to be in (cost of startup), choosing a lawyer (and ask for his law school transcript), choose an accountant, choose a bank (check their lending limits and approval process), choose your employees (your most important asset).  The Fear of Zeros is anxiety builds as the dollar amounts grow substantially, but you need to get over it and at large amounts the bank becomes your partner and wants you to succeed.  If you're successful, you will accelerate so be ready for the ride and never drop the ball.  To get rich, work for your own company, as your security, benefits and salary are up to you.  The secret is to build the business with the intention of selling it off.  You can then either retire and live the good life or start another company and do it all over again.

George then brought Jack, Sebastien and Michael into the discussion.  Jack talked the Players and the rest of the population.  Players are the innovators and serial entrepreneurs who are addicted to this kind of work.   Find something you really like to do, aligned with a higher purpose, goal or mission.  Do it a lot until you get good at it, and then people will pay you for it.  Michael suggested finding a mentor, and the SCORE program can provide some valuable free advisors.  Sebastien says that being the boss takes a great toll on you personally and he has to work twice as hard as everyone around him.  Mark said he didn't have a business background, but he learned bookkeeping so he would understand what a good bookkeeper should be doing.  Jack said he hired an accountant right from the start who did all reporting correctly which helped him in the end when he sold his business.  Jack suggests that you plow all of your money back into the company in employee salary, R&D, capital expenses, etc. as this will reduce your taxable profits.  George is concerned with his monthly outgoing money and projected monthly incoming money.  The accountant will keep track of the details.  Jack was concerned with daily cash balance, and he paid all of his bills on the day they were received, not 30 days later since that money belongs to somebody else.  Some companies try to stretch their payables but that's a mistake.

Anne asked about how the panel handled bank and investor cash infusions.  Michael said his first inflow was with a bank, and he built a personal relationship with the president of his bank.  Sebastien took over a solar company with no clients and some debt, so he had to put in a tremendous amount of work for 3 to 5 years to get the company moving and then banks become interested.  Jack said he started a business for $80 and sold it 11 years later for $38 million, without putting any more of his money into it.  He stressed that it all comes down to selling, not matter how much innovation and hard work you do, it's all about taking in money from customers who want to give you money.

A question came up about feeling that weekends were getting in the way of running the business and Jack said he hates showering because it takes up valuable time.  The board agreed that people with the drive succeed when they put in the effort.  Jack likes to bring good people into his team and let them work hard and experience the excitement and process, and pay them well.  Leaders exploit their skills and then hire people into the team to bring in missing skills until all pieces of the puzzle are in place.  A point was made that a 1 - 15 person company can be mangaged by one person at the top, but anything above that requires layers of management and you have to be ready for the growth.  Jack talked about plateaus, you get to a point and support that, then jump to the next one.

Andrew McClary told us about his experiences in the world of television and how it led to his new startup of a consumer-oriented hot rod electric conversion shop which will be supported by his video skills.

George said if you fail one time and quit, that's sad.  Jack believes he can objectively analyze his failures and use that information for the next thing.

A question came up about product liability and George says he has Product Liability Insurance.  Jack says he had to have insurance in certain circumstances, but avoids it when possible as it attracts lawsuits and lawwers.

We then headed down to the park for the public car show.  Just a few pictures as I took a bunch of most of the same cars last year.  A lot of interested people showed up to check out the cars and ask questions.  Dave Hrivnak, with the blue Tesla Roadster, gave an interview to a young woman from college radio station, and then gave her a ride.  She came back with the expected EV grin!  I can't find a link to the interview, so if you find it, let me know.

We then drove in a police escorted parade through town back to the hotel, where we posed the cars and took some group pictures.

And a little video of the celebration!

After a short nap, we then headed back to the Show Me Center for the banquet and awards.  I forgot to take pictures!  At about midnight I stumbled back to the hotel to get some much needed sleep before leaving for the airport in the morning.

One thing to note is Jack did not announce EVCCON 2013!  He discussed this in the video he released after the show, saying he took a loss on the show again and isn't sure if it's worth the time and effort, and if it should stay in the same format or change.  Richard wants people to call him and give him support to run it again.  Keep watching EVTV to see how things firm up.

Friday, September 28, 2012

EVCCON 2012 Day 2

After sleeping through my alarm for 30 minutes, I arrived at the Show Me Center just as Wayne Alexander was starting his session on EV conversions as a business.

He regaled us with pictures and descriptions of a half-done Mazda project he took over.  Literally everything was wrong, so he showed us how he fixed everything and rebuilt it back to a working car.  Then he moved to a Jeep project that had been worked on for 17 months and abandoned.  The work was so bad it was actually dangerous, with the possibility of fire and shorting of the battery pack conductors to the drive shaft.  He showed us his method of mounting non-electronic automatic transmissions to the motor.  He likes to mount the controller, contactor and associated electrical parts on a thick sheet of Lexan and mount it above the motor under the front hood.  He makes his battery boxes out of 1/8" steel.  He suggests that you work on every car that comes across your path, don't be afraid to try new things, but try to standardize on a small set of components that you know and trust.  Simplicity is best, as it leads to fast builds and working EVs.  He stressed that we have to do conversions well because one bad car will taint our whole industry.

Next up was David Kerzel on charging port issues for J1772.

He started by talking about electrical safety, as there is a perception that gasoline is safer than electricity, but there were 250,000 gasoline car fires and a handful of electrics.  The J1772 standard brings together a common connector and an electrical safety protocol.  The connector has a well-thought-out design, with no exposed wiring, ground mates first, the proximity switch engages and then the 3-stage safety protocol happens to ensure the car is ready to be charged, then power starts flowing.
  • J1772 Level 1 is normally 12 amps at 120V.  You can normally get 6 hours per mile of charging time.
  • J1772 Level 2 is normally 23 amps at 240V, giving 27 miles per hour of charge.  A few 80 amp charging stations exist which will give about 93 miles per hour of charge.
  • J1772 Level 3 is a completely different beast.  It is high-current DC power rather than AC power.  It bypasses the charger in the car and dumps power directly into the battery pack, matching voltages as necessary.  Nissan Leafs are equipped with CHAdeMo, which handles 500V DC at 125 amps.  SAE is working on a J1772 standard, which adds two large posts for DC onto the bottom of a Level 1/2 connector.    It is expected to handle 600V DC at 200 amps.  The safety protocol has not been determined yet.  This system has been accepted by GM, Chrysler, Ford, Toyota, Honda, Nissan and Tesla.  No production cars use this yet.
Why are EVSEs (Electric Vehicle Service Equipment, what most people call a charging station) so expensive?  First, is safety, as the connectors and wires must pass strict rules.  Then the units have to be robust to handle years of charging, weather, vandalism, etc.

The Tesla Supercharger network was just announced this week.  Tesla says it is a 90 KW/hour system, taking 20 minutes to charge for a 3 hour drive, but David's calculations show a 20 minute charge will actually take a Tesla Model S about 80 miles.  With all 6 charging bays in operation, that will pull over 500,000 watts of power, as much as my company installs on the roof of a Costco store.  David wonders if the charging will always be free and doubts the $250,000 construction cost quoted by Tesla.

David says when you find a public EVSE, check it over for damage and try to notify someone if it needs attention.  What do you do when a non-electric car is parked in the spot?    Be polite and move your car when done charging and coil up the cable nicely.

David worked through different adapter cable scenarios.  It's important to remember that J1772 connectors are not rated to plug and unplug when energized!  There are several EVSE open source projects on the Internet using Arduino controllers.  David sells his 4th generation EVSE controller and display unit as a kit.  Data connections are important for commercial customers as they want to know how much power and how many cars are being charged, as it's essentially an advertising cost to the business.  If you buy a fully-assembled EVSE it must be UL listed, but if you buy it as a kit, your electrical inspector must approve it, following National Electrical Code Section 625.

David discussed his future plans which include GFI integrated into his products, adding soft current limit, timers and communications to cell phone for commands, settings and statistics.

Next up was Steve Woodruff, talking about his Prius plug-in kit and finding parts to build your EV.

Steve competed in the 2009 X-Prize competition with a heavily modified Prius.  His primary business is to recycle parts from damaged Priuses (Prii?).  He built a stretch Prius plug-in limo.  He supplies repaired Prius touchscreens, shift levers, cables, battery cells or packs, and sells his own supplemental plug-in battery pack.

His tip is to buy the whole wrecked vehicle, as all of the parts can eventually be salvaged.  You can get leads on cars through insurance company auctions, Copart auctions and Mannheim auctions.  Always bid assuming there is more damage than you can see.  You need to be registered as a vehicle dealer and your buyer fee will be $495 and 90c / mile shipping.  If the car has a Certificate of Destruction or Junk title the car cannot be rebuilt, only sold for parts.

A Prius has a 1.5 liter Atkinson cycle engine, which means all 4 cycles of the engine are completed in one turn of the crankshaft rather than the standard two.  There are two large generators in the drivetrain and an AC motor.  It has a continually variable transmission that merges the power from the engine and motor.  He prefers to work on the Generation 2 Prius model although Generation 3s are on the road today.

The Prius doesn't have a power steering pump, belt-driven AC compressor or alternator and no starter motor.  This is a big difference between traditional engines.  There are 28 Nickel-Metal-Hydride cells in the pack which are built into a slab.

There are a couple of other Prius plug-in conversion shops around.  Steve has 22 conversions on the road.  A Prius requires about 1 KWH to move 3 miles so a large 10KWH plug-in upgrade will allow for 30 miles under electric power, then reverts to normal Prius mode.  Steve has also rebuilt several Prius built-in battery packs and has only had one come back with a repeat failure, and Steve stood behind it with a warranty.  It costs about 1/3 of a new pack, so customers are willing to take the chance.  He matches the voltage of the replacement cells with the state of the existing pack to avoid bottom balancing issues.

The key to making a plug-in pack work is that the Toyota software has been hacked to allow for the car to go to at higher speeds in electric mode than was originally designed.

Keegan Han from CALB batteries was supposed to be a speaker, but his parents arrived from China and cancelled his appearance.

Next up was Rich Rudman from Manzanita Micro, maker of chargers and motor controllers.

Rich has a long history in the EV world with chargers, controllers and battery management systens.  His first electric car was a Ford Fiesta drag racer.  The first charger was the PFC-20 which could take 120V or 240V AC.  The PFC-50 came next which would take in up to 50A, giving 10KW of power.  Then the PFC-75 came with up to 20KW of power.  These chargers must be run in a cool environment or they will overheat and derate the output.  New models are coming out with a new enclosure and dial-wheel voltage adjustment.  A new meter shows input voltage, current, KW and power factor.  Additionally they will directly support J1772 protocols.

The Zilla controller is legendary and has gone through a lot of turbulence of owners.  Rich now owns the Zilla product and has brought it back into production.  He is building the current version now and has several enhancements planned for early next year.  The Zilla 1K unit is a compact water-cooled unit running 1000A.  The Zilla 2K unit handles 2000A.  They also have a limited edition Zilla 4K unit.  The Hairball unit moves all of the input signaling out of the main controller box to avoid costly failures.

They offered a BMS system staring in 2008.  He feels strongly that BMSs are required and top-balancing is the only solution to pack setup.  This is in violent disagreement with Jack.  He also said that all Lithium battery manufacturers require a BMS or the warranty is void.  He showed a screenshot of his display which gives a good view of the behavior of each battery, whether he is regulating the top charge or not.  The question came up about running a small wire to each cell, and Rich said it's an issue but solvable with circuit-board solutions, properly bundling wires, etc. and they have not had any failures that weren't traced to installer error.

There was a lively discussion about dissipation of energy during charging shunting phase and throttling back the charger.

A quick break for lunch and we're back for Tom Brunka and his session on The Helwig Carbon Brush in your Series DC EV Motor.  Tom's was the blockbuster session last year, with lots of great information about motor brush compounds and construction and the direct effect they have on your performance and range.  Jack did extensive testing of the split Red Top brush design and Tim found his range was extended by more than 10% just by swapping brushes.

Tom gave us a video tour of his factory.  They manufacture not only brushes but brush holders and constant force springs.  There are 3 different grades of materials
  • Electro-Graphite: High end, used in EVs
  • Metal Graphite: up to 48V DC
  • Graphite: up to 90V DC
Within these types, there are many grades, with different levels of resistivity, strength, hardness, friction and filming, leading to different brushes designed for different applications.  Brushes are sized based on current density.
  • H38: Up to 80A per square inch, long life for street EV usage
  • H49: Up to 100A per square inch, untreated for racing
  • H60 Up to 80A per square inch, street EV usage
  • K254: Below 80A per square inch
The film is an important part of motor operation.  It builds up on the commutator and acts as a dry lubricant allowing the brushes to glide over smoothly.  It should be a nice dark brown color without arcing indications.  Resistance comes into play as it affects the temperature that the brush runs at.  Tamping material can be copper or graphite and bonds the shunt wire to the brush.

Brush wear factors include mechanical friction, electrical arcing, spring force, humidity (helps to create and maintain the film) and commutator wear.  The target spring force for most electric motors is 4 psi at the brush face, in an EV the minimum should be 8 psi due to bouncing and vibration.  You can add one-half to one more bend on the brush spring to gain a bit more brush force.  A sign of not enough brush force is marks on the face of the brush.  Better contact means better electricity transfer and efficiency and therefore less heat.

Arcing has many sources, including the advance/retard of the motor timing, contact area, roundness of the commutator leading to the brush bouncing right off, spring force and heat soak.  

Helwig suggests seating the brush to 80% before using it in a normal application.  This can result in running the motor on a 12V battery in neutral at 3000 rpm for several days.  H49 seats quickest in 6-15 hours, H60 seats in 6-7 days, H38 seats in 17 days!  They suggest beveling each commutator bar at 45 degrees, then lathe cut it round, then polish with 80 grit and 150 grit garnet paper only.

They suggest using a Grounding Brush Kit due to inducing of current into the bearings and the driveshaft.  One customer read 20A being drained off after installing one of these kits.

As the brushes wear, they turn to dust and can lodge inside the motor, starting a frame leak.  Blowing the motor out 4 times per year is a good rule of thumb.  It's also a safety precaution to add an active blower to your motor, which helps with cooling and cleaning out brush dust.

Never use silicone spray, grease or sealer in the vicinity of a DC motor, as it will contaminate and attack the brushes due to the conversion to Silicon Carbide.

Acetone is the preferred cleaning solution, but make sure it's completely removed as it's highly flammable.

New developments on the horizon include new manufacturing processes and grades of brushes to meet the needs of the market.  They are looking at larger shunt wires, tamping materials, higher current handling by adding silver (but expensive) and new brush holder designs.

A question came up about overheating EV motors due to the nature of driving.  Tom suggested adding blowers to keep the motor and brushes cool, they must be below 400F.  As a science experiment you can drill a hole in a brush and epoxy in a thermocouple to directly measure brush temperature.

There should be an ink stamped part number on the side of each brush for easy identification if you're repairing or upgrading a motor.

Tom says they use a fish scale as a crude way to measuring spring pressure in the field.

The last speaker for the day is John Hardy from the UK.  He has contributed videos to EVTV and is speaking on battery testing.

John has a varied background as an engineer, car accident analyst and commercial pilot.

Why do we test batteries?  There is little data, so it was a job that needed doing and he wanted to do an electric car conversion and wanted to make sure he picked the right batteries and charged and discharged them properly.

The conventional wisdom held that batteries drift apart in voltage in a pack and you need a BMS, so he wanted to use science to see if that is actually true.  There is a lot of data out there about Lead Acid cells, strings and batteries.  They self-discharge just by sitting there, called the Peukert Effect.  Many people seem to think that these principles carry over to other battery chemistries.  Lithium Iron Phosphate batteries do not self-discharge, but there is little additional data or analysis.

John built a test rig with a charger, a load and a series of Headway LiFePO4 round cells, and used an Arduino controller to manage his test processes.  His voltage measurement tool consumes 0.2 ma which has a non-trivial effect on the pack, so he added an OpAmp to isolate the metering from the pack.  He used a language called "Processing" and a cloud data service called Pachube and CSV files into Dropbox to collect and store the data.  He then pulls the data and graphs it.

After months of 3C charge and discharge cycles, his results indicate he saw almost no variation between cells at the end of the discharge cycle from his bottom balancing variation, but a small amount of variation around 6 mV between cells during the constant voltage phase of the charge cycle.  By removing the constant voltage charging phase, the cells had nearly zero variance throughout the charge and discharge cycles.  He then added a "top-up" charge after 5 minutes of rest after the constant current charging phase with a tiny variance, then a "double-top-up" charge, with a slightly larger variance, of about 3 mV.  At a lower charging rate of 1C, the pattern remained the same.

The bottom line is there was 10 mv, or 0.3% discernable drift between cells, no matter what the charging cycle or charge and discharge rates.  This is as close to zero as is measurable.  So John has shown that there is no risk of Lithium cell drift in a pack.  As long as the cells are bottom balanced at the time of installation, they will behave beautifully through their lifecycle.  He did have one cell fail around cycle 575, so this needs to be taken into account to detect a failed cell in a pack.

He is going to do another test with CALB cells to see if they also hold up to this profile.

We all packed up and headed over to the airport for 1/4 mile drag racing, autocrossing and dynamometer testing!

This is Jack's hanger at the airport, where the food, drinks and portable dynamometer machine were housed.  Normally there are two DC3 aircraft parked here, along with Jack's collection of MGs you can see below.

Here's a closeup of the portable dynamometer.  Jack paid for it, and it was free to anyone to use for 2 or 3 runs.

The cars started to get staged outside, in preparation for SCCA-sanctioned 1/4 mile drag racing, starting with the weigh-in.

Ron Adamowicz, with his last pennies, brought his unbelievable dragster to the event.  Now the hood is off here, so it's hard to picture, but this is the size and shape of a Funny Car.

It has two 11" DC motors, 2 lithium battery backs and two Evnetics Shiva motor controllers.  I mentioned earlier that each Shiva can pour 3000 Amps and 1.2 million watts of power into a motor.  Now just imagine that Ron's car has *two* of them.  That's 2.4 million watts of power.  Boggles the mind.  Check out his two runs in the drag racing video below.

Here is Fred Behning's gorgeous completed-just-in-time-to-put-on-the-trailer MG TD.  He won the trophy for Best Paint at the awards ceremony.

Alex Smith's Wrightspeed lookalike looked insanely fast but was held back by its lead-acid batteries, same as my 914.  With a lithium pack, this car could beat the Teslas.

Doug Ingraham's RX7 looked fast.

Holding the torch for the 914 brigade was Mark Emon with a crazy 56 200AH lithium cells.  After finishing his build at home, he drove it 2 blocks then put it into the truck and drove to the show.  He spent arrival day in Jack's shop finishing up details like replacing his coolant pump and hooking up the charger wiring.

Next up was Kevin Heath's RX8.  Kevin picked up 3 trophies at the award ceremony for this fantastic car, with a battery pack made from A123 lithium pouch cells.

We got to watch John Allan build this Celica via videos he would record then send to Jack for inclusion in an EVTV episode.

This is Norbert Kedzierski's Boxster.  His company, Red Point Engineering, among other cool things makes electric conversion kits for Boxsters.  It is his daughter's 7th birthday today and she didn't seem to mind spending time with the electric cars.

This is Stella Kostolina's and Zachary Vex's Tesla Roadster Performance machine.  It's black on black on black and looks amazing and goes even better.  Stella and Zachary are making a reality TV show called Electric Trippers which follows their journey as they drive around the country, meet interesting people and try to find places to plug in.

Here is Jack's Porsche 550 Spyder replica.  It used to be owned by Duane Ball, but Jack bought it when Duane decided to go ahead with his Porsche 904 replica project.

Here's the race start position.  The helicopter is not for emergency flights to the hospital!

I got most of the cars racing on the drag strip.

Fred let me take his MG TD for a couple of runs, here is the video:

These are my two run slips.  The first run was good, with a 19.489 quarter-mile time, at 62.5 mph.

The second run was worse, as in my enthusiasm I knocked the throttle linkage off the pedal when shifting into 3rd gear.  I had to reach down and push it back into place, hampering my time to 23.555 seconds and 49.3 mph...

The autocross track was open and most cars headed over after doing a couple of drag strip runs.  Here's a video of Charlie and Tamera in the Opel GT.

As the sun set, most people brought their cars over to the dynamometer test rig.  Here's Charlie's run in the Opel GT.

And his graph shows he's making 104 horsepower, which is excellent for such a light car.

Then Mark's 914 with the enormous battery pack was on the ramp.

Then Caleb Lander got his 1974 Super Beetle up on the ramp.

It has a relatively small lithium pack but made a brave 39 horsepower.

Then things got very interesting when the Evnetics team got Sebastien's 911 ready for testing.  The first two runs actually had a controller shutdown because the 12V power bus voltage was too high.  They solved the problem by turning on the headlights!

And turned in an amazing 356 horsepower!

Next was Stella and Zachary's Tesla.

That's 256 horsepower.

Last up for the day was Jack in the Speedster, a sleeper of a car with a large pack and surprising power.

That's 160 horsepower, folks.  About twice what most of the original cars left the factory with.

After things wrapped up here, a group of us went to a local bar and enjoyed ourselves thoroughly.  Got to bed about 2 AM...

Thursday, September 27, 2012

EVCCON 2012 Day 1

EVCCON 2012 Day 1 kicked off  at the ShowMe Center (having outgrown Jack's airplane hanger last year) with a quick tour of the electric cars on display and the vendor booth area.  There are about 40 cars already here this morning, some returning from last year and some great new ones this year.

Here is Fred Behning's MG TD that he completed only days before putting on the trailer for the show.

Sebastien Bourgeois and the Evnetics team brought the chocolate milk-colored 911 again, but it's been heavily modified with two matching Soliton 1 controllers and a new clutch.

A newcomer this year was Zachary Vex's Chevette dragster.

Yes, that is an Evnetics Shiva controller!

Here is the booth area:

This is the Evnetics booth, a small group of very smart people who among other cool things make electric motor controllers.

The Soliton 1 and Soliton Jr are available and are market leaders.  The Shiva on the left side, is under development and will be able to handle 1.2 Million Watts of power.  To put this in perspective, this is more power than can be made by solar panels on the roof of TWO Costco stores!  That's 1600 horsepower, and 3000 amps into your motor.

This is John Hardy.  He wrote a book about converting cars to electric drive called ICE-Free.

This is David Kerzel from Modular EV Power.  He makes a lot of great equipment to get power into your electric car, following the J1772 charging standard.

NetGain Motors has a couple of booths, showing their WarP line of motors and a new line of NetGain Controls motor controllers.

This is AutoBeYours, which specializes in finding crashed Priuses and Leafs and fixing them up, rebuilding battery packs or selling the parts.

This is Red Point Engineering who has designed kits to convert Porsche Boxters to electric drive.

Jack kicked off the conference with his keynote speech.

In fine Jack style, he highlighted a point from his video last week that the end of the world just happened - On September 6, 2012, China opened an oil trading market, in Chinese RMB, and Russia signed up to sell them all of the oil they want.  The US Dollar, and its perceived strength, is no longer the world currency.

This of course led him into his belief that electric cars are the transportation solution for the future.  He paralleled the development curve and innovation of computers to electric cars, and innovation can only be done by two guys in a garage, but you need a large organization to scale past the building of the first product.   Most innovation is driven by people who want to do something for fun.  As their work progresses, they gain the interest of others, and provide the foundation  for further development.

Even with Tesla, Nissan Leaf and Chevy Volt in the market, we are still millimeters along the early adopter phase.  Early Adopters are 2.5% of the market, which is 375,000 cars in the US market.  We are currently 1/10th of that number.

Geoge Hamstra from NetGain Motors did the keynote speech called "Brushed, Series Wound DC Motor Enhancements, a Continual Process", following up on his speech from last year.

George made his fortune in the early days of PCs and retired.  He then got bored and decided to drag race electric cars.  When he kept blowing up motors, he got into the design of motors and now heads NetGain, arguably the most popular motor for electric conversions today.  He partners with Warfield as his manufacturer, giving them his specs.

George I think stunned the audience by saying it was costing his whole EV motor profit for 2012 to bring his team to this show but he wanted to come as we are a large part of his existing and future customer base.  He's subsidizing EV motor work by the higher cost he charges to OEMs.

He said his goal is to make the finest motors at an affordable price.  He has been on a constant, incremental improvement program since taking the helm.  He has to balance any improvements with the cost of engineering and resulting impact on the motor's price.  He also has several OEM customers who need long-term stability.  He has to commit to a large number of motors for any design change, so he has to ensure that there will be sufficient demand or he's stuck with a shelf full of motors.

Last year he added 29 improvements and wants to continue this with things like increasing the size of the terminal studs from 3/8" to 1/2", increasing the diameter of the drive shaft to 1.125", improved brush compounds and an improved fan design.  With all of these changes, he only increased his price by $50 in the last 3 years.  There is a non-trivial, well-defined process of evaluation, agreement, CAD file updates, prototypes, testing and production.  He's been thinking about a major improvement of liquid cooling for 5 years but doesn't have a feasible design yet.

He only ships about 900 motors per year to all EV dealers and conversion shops, so he needs to increase his market.  He's moving into outboard boat motors, with a line called D-Sea, converted to electric drive.  He wants our group to step up and become boat converters too.  He's working on further improvements with bands over the balancing putty, better tooling for commutator construction, new brush compounds, modified drive-end shafts and forced air cover bands on the 11" motors.

He said that the commutators are spun-tested in the factory to 10,000 rpm and the bearings are rated to 14,000 rpm, but he doesn't want anyone to get hurt by over-revving them.  Brushed DC series-wound motors drop off in power at 4000 to 5000 rpm, with a sweet spot of 2000 - 4000 rpm due to cooling, so don't run the motor too slow or too fast.  A dual-motor BMW made it to the top of Pike's Peak (more later) but George was surprised it made it.

When you change brushed, be sure to blow out as much carbon dust as possible.  Brushes that are treated well can go 100,000 miles or 3000 - 4000 hours of operation.

George wrapped up by half-disclosing a new motor model he has under a black sheet that has water cooling, but he can't talk about it anymore until the manufacturer's rep shows up in the next day or so.

John Metric was the next speaker, talking about making high performance cars from stock EV parts.

John is heavily involved in the electric drag racing world, with a converted Pontiac Fiero called DC Plasma, which did a world record 155 mph in a standing one mile run.  He is President of the National Electric Drag Racing Association (NEDRA).  His car does 0-60 in 2.3 seconds and 1500 ft-lbs of torque, using stock WarP 9 motors and some interesting direct gearing.  He got interested in electric racing from seeing electric snowmobile racing in northern Alberta.  His work with electric furnaces helped him jump into this world.

He first did a battery and capacitor analysis to determine which was the best for his purposes.  He quickly came to the realization that LiFePO4 batteries were his best power/weight ratio.  Range is not important in this use scenario! This led to dollars per second analysis, which led him to a design with Enerland battery packs made from A123 pouch cells.  They are common in the Radio Controlled car and airplane world.  752 of these cells gives him 800 horsepower.

He measures and collects amp, voltage, temperature, pedal position, RPM and torque data from every run, so he can perform extensive analysis, and he does so in great detail.  He uses roughly 33% of the pack capacity in one run.  The second run on a charge tends to be better due to the temperature increase from the first run.  He showed us several graphs including a PVI chart measuring Power / Voltage / Current of different pack configurations.  He then showed G-Force data, showing the effect of different gear ratios vs MPH at the end of the quarter mile.  He showed us several charts as he added a second Zilla 2K controller and made incremental improvements in the battery pack, controller, motor and drivetrain.  He wrapped up by showing some of his runs on video.

After lunch, Michael Bream and Matt Hauber spoke about their 2012 Pike's Peak Hill Climb effort in a converted 1995 BMW M3.

Matt spent 6 months working for Jack and then moved to San Diego and launched his own career in the EV world.  He met up with Michael and they launched EV West.  They were going to bring the car to the show, but most of the differential was in a Ziploc bag.

They ran 11:58, 4th place in the Electric Class behind 3 purpose-built racing cars.  Most impressively they beat every vintage car in the event.  This car has the flexibility to be a daily driver too.

Why do they race?  Racing has given us nearly every improvement in automotive technology over the years, it gives great exposure to the EV world to the public, increases communications with vendors and assigns performance numbers to the cars which can be directly compared to other cars.

They went to Pikes peak because of the history and the challenge.  It's a great venue for electrics because it's only 12.5 miles, huge torque helps with the grade and 156 turns, and the thin atmosphere doesn't negatively affect electric motors.  They were worried about crashing, falling down a cliff or into the woods and it was the first true test of the car.

Why did they choose the BMW?  It's codename E36.  It has great stock performance, the front clip comes right off aiding in construction, strong driveline, lots of aftermarket parts, previous experience with earlier BMWs, good selling price for the pulled engine, and the car is popular among home racers and fans.

How did they convert it?  Extensive race prep, safety compliance, chassis and drivetrain updates and tuning had to be done.  They had to go with a PowerGlide racing transmission because the dual 11" motors were shredding clutches.

They were going to have Boris Said drive the car, but the race was postponed by 30 days due to wildfires and Boris had a conflict, so Michael drove the car himself.  During the race they had a generator / charger fire in the pits!  Overheating in the race suit was an unexpected problem.

Lessons learned after the race: run data loggers in the car, they had 60% more battery pack than was needed, experienced 30-35% voltage sag, melted batteries actually survived!

How much did it cost to convert and run the race?  $2,500 in car, $8,000 prep, $16,000 batteries, $10,000 drivetrain, $9,500 electronics, $2,000 travel and testing.

Next up for them is more racing, car shows, BMW club, autocrossing, kits for EV conversiona and building a Class 1 Baja 1000 race vehicle, with hot-swap, slide-out battery packs.

I asked them to play the video of the run to the top, but they didn't have it on their laptop.  You can find it on YouTube.

After a quick snack, Sebastien Bourgeois from Evnetics / ReBirth Auto was up, to discuss operating a small conversion shop.

Sebastien talked about the Shiva controller and its performance in the Pikes Peak run.  He apologized for not delivering on his promise of a charger, but says plans are in place and going well for a state-of-the-art compact, robust, water-cooled, broadly-adjustable input and output, 50/60 Hz, J1772-directly-supported, maybe-DC-input programmable charger, in the range of 5KW - 30KW.

Evnetics is a small company with no outside funding, and must rely on developing products that the market will like and buy.  Those of us considering starting up a small conversion business must face the same decisions.  Everything is new and exciting and has never been done before in that way.  It takes a lot of time and effort to educate your customers and provide the value of your expertise.  He scaled back his conversion business to focus on the component development, and wants to work with small auto repair shops to become conversion experts.  He was asked about development of a DC/DC converter and whether they were going to make an integrated charger & DC/DC converter, and he confirmed both.  The charger will be a blank-sheet design, breaking with a lot of ideas carried forward from the past.  He has developed an AC controller platform and is looking for the market in order to make it a product.

Next up was Brian Bohm from NetGain Controls and EV Source on breaking the power flow in high-current systems.

Ryan stressed that electrical safety is boring, but is critical to the success of your overall project, components and life.  There are many aspects to correctly designing your circuits and choosing the proper fuses.  He drew a schematic with the fuse placed on the output of the + of your battery pack., between the pack and the contactor.  The fusing must be sized so a direct short to ground will not damage the wire before the fuse blows.  If you have current draw just less than the fuse rating, you must size the wire to handle it.  All devices in all branches of the circuit should be fuse protected to their maximum current draw.

Fuses are obviously rated for maximum amps, but they have different compositions which gives different maximum voltage limits, and temporary overcurrent time limits so they don't blow instantly on a tiny spike which would otherwise be tolerated by the circuit.  The wires in the circuit are generally not modeled, but the internal resistance of the battery pack is.  In LiFePO4 batteries, we are looking at milli-ohms of resistance.  You need to choose a fuse with a sufficient short-circuit current calculation, which can be on the order of 3000A.  Photovoltaic fuses are rated at 20,000A which make them good candidates.  Large, expensive fuses are rated for up to 500,000 amps and are suitable as the main battery pack fuse.  Keeping the + and - conductors in your pack close together or even twisted together will decrease the inductance and make your fuse's job easier to blow properly and protect your wiring  Consult the fuse's chart to determine how long it will take your fuse to blow at a certain rating and a certain overcurrent.

Ryan then moved on to contactors.  Contactors are generally heavy-duty relays, which are automated on/off switches.  Contactors are rated to be able to break a very-high current circuit.  Contactors have a failure mode where the switch contacts weld together and continue to conduct when the solenoid is desperately trying to separate them.  This leads to wire overheating and melting, and destruction of downstream devices. Contactors depend on the gauge of the attached conductors to transmit away heat from internal resistance and help avoid welding.

Jack asked which kind of fuse to use in several common EV scenarios.  Ryan stated you have to start at the load and work backwards, taking the conductor size into account.  Car wire lengths are very short, much shorter than industrial equipment or building installations.

Ryan wrapped up by saying that neatness of the installation is actually part of the National Electrical Code.  A mess of wires is inherently unsafe.  Always use insulated tools, take off glasses, rings and watches and wear appropriate personal protection equipment such as safety glasses, leather gloves, etc.

Finally Ryan discussed how to reduce cost and complexity in the EV conversion world.  He discussed integrating what have been traditionally discrete components such as charger and controller.  Both need switches, cooling and logic boards.  With some inspiration from Jack, he's introducing the Pulsar.  It has:
  • Native J1772 charging with up to 90 - 260V at 100A AC service, 3-phase power capability?
  • DC fast charging with up to 300A at 370V, which is an astounding 111 KW
  • Integrated 50A DC/DC converter
  • 500A motor controller with all four motor connections.  Higher power systems will come later.
  • Can drive an external controller if 500A is not enough right now
  • Integrated contactors 
  • Can charge an external device such as another EV
  • CANBus data connection that can be accessed via the OBD II connector
  • Can also be configured via a smartphone.  
Price is $3000 - $4000.  Holy crap!  This is very cool!  It folds multiple devices into one and costs much less than the sum of the parts.  They want to release it by November 15.  Jack has it posted at the EVTV store, with some additional details.

We are now preparing to move the cars out to the lawn to take a group picture.  After that we're getting a BBQ dinner and live band inside the Show Me center due to scattered showers in the area.  Pictures later if anything embarrassing happens.