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.
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.
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