Dr Automotive Design and Tools

La Fiat, appena sbarcata di nuovo sul mercato americano acquistando la Chrysler, ha un potenziale di innovazione per l'auto simile a quello della Apple per i computer e la telefonia mobile. Lo scrive il settimanale americano Time nel numero di questa settimana. Secondo Time, l'ad Sergio Marchionne "ha sfruttato Apple come un modello", concentrandosi sul modo in cui Jobs ha trasformato l'azienda in "una icona globale del cool".
(Fonte: www.time.com - 18/6/2009)

Since Subaru announced the world's first mass production lithium ion battery powered plug in electric vehicle would go on sale next month, a few motoring publications have got their hands on one if only very briefly. Edmunds took it for a spin but the contributor obviously is not up to speed technically on Evs as he kept referring to the cars constantly variable transmission (CVT). As with all Evs the Stella has a single speed reduction gearbox for maximum energy efficiency to the wheels and because the 47 Kw (63 hp) BLDC electric motor has 170 Nm (125 ft/lb) from zero rpm.

Caradvice.com.au took an early prototype for a spin in February and the Stella EV has some interesting features. The gear lever the Edmunds writer was confusing with a CVT is actually use to adjust the level of brake regeneration the driver prefers. With the 'transmission' lever in D the car drives with mild regen. Putting the lever into L engages heavy brake regeneration and the Subaru EV can be driven in city traffic almost completely without using the friction brakes at all.

There are a couple of unfamiliar gauges in the instrument cluster. Replacing the fuel gauge is a battery charge gauge with increments in km. Interestingly it is not a linear scale as while 'full' is 80 km, 2/3rds full equals 30 km range. The second new gauge shows how much power the motor is drawing or returning to the batteries.




The Stella Ev tops out at a max speed of 100 kph (60 mph) which Subaru say helps keep to energy consumption in check and the batteries cool. Seeing as around 100 kph is expressway speed in most countries it seems a reasonable limit for an urban commuter car. The Stella body shell isn't the most aerodynamic we've ever seen and as aero load increases as the square root of speed (i.e. double your speed and you quadruple the wind resistance) the shape of the car, no doubt, has a lot to do with the imposed speed limit.

Range from the small 9.2 kWh battery pack of 90 km (55 miles) is quite impressive when you keep in mind that much like the Chevy Volt, not all the battery capacity is used. In the Volt only 8 kWh of the 16 kWh capacity is actually usable.

It is believed Hitachi Maxell are the suppliers of the high performance Lithium Ion batteries found in the Subaru Stella EV. The battery will accept an 80% charge in as little as 15 minutes or take 4 hours to charge with a 240 volt outlet. Perhaps the best part of owning an EV is how much they cost to run. To 'fill' the Stella will cost less than $1.00 @ $0.10 kWh. The additional weight of the battery only ads 120 kg to the car compared with the ICE version and curb weight is still in the 'lightweight' range of around 1000 kg.

Ten points to Subaru for being first to launch a production li-ion battery powered EV while other car companies, noticeably Toyota, who even in their 3rd generation Hybrid still don't sell either a plug-in or lithium ion batteries.

While some headlines have focused on the relatively expensive purchase price of these new Evs due to the very new technology in the batteries, if you add up your fuel costs with an ICE powered car over the life of the vehicle, in many cases you will have paid more to fuel the car than you did to purchase the car in the first place.


Plug-in Stella specifications:
Dimensions (Length x Width x Height): 3395mm ×1475 ×1660
Curb weight: 1060 kg
Passenger seating: Four
Maximum speed: 100km/h
Per-charge driving distance: 80km
Electric motor: Permanent magnet synchronous motor
Max. power output: 40kW
Max. torque: 150Nm
Drive-train: Front-wheel drive
Battery type: Lithium-ion batteries
Total voltage: 346V
Total energy capacity: 9.2kWh

Northrop Grumman Corporation have successfully load tested the most powerful electric motor ever tested by the U.S. Navy and the world’s first 36.5 megawatt (49,000 horsepower) high temperature superconductor (HTS) ship propulsion motor, double the Navy’s power rating test record.

Incorporating coils of HTS wire that are able to carry 150 times the power of similar-sized copper wire, the motor is less than half the size of conventional motors. It will help make new ships more fuel-efficient and free up space for additional war fighting capability.

This system was designed and built under a contract from the Office of Naval Research to demonstrate the efficacy of HTS motors as the primary propulsion technology for future Navy all-electric ships and submarines. Naval Sea Systems Command (NAVSEA) funded and led the successful testing of the motor.

The Navy has invested more than $100 million in the development of HTS technology, paving the way not only for use in Navy ships but also in commercial vessels, such as cruise liners and liquefied natural gas (LNG) tankers, which can also take advantage of the space and efficiency benefits of HTS motors.

Technical Background

Load testing demonstrates how a motor performs under the stresses and operating conditions it undergoes when powering a vessel at sea. This final development stage of the motor provides engineers and ship propulsion integrators with vital information regarding design options and the operating characteristics of the new superconductor motors.

Significantly, the HTS motors being developed by American Superconductor involve no major changes in fundamental motor technology. The machines operate in the same manner as conventional motors, gaining their substantial advantages by replacing copper rotor coils with HTS rotor coils. The rotors of HTS motors run "cold," so they avoid the thermal stresses experienced by conventional machines during normal operation. The inability to achieve proper thermal management has been a key impediment in developing power dense, high torque motors required for naval and commercial marine applications. Stresses caused by heat in other advanced, high power motors often necessitates costly motor repair and refurbishment.



The 36.5-MW (49,000 horsepower) HTS motor does 120 rpm and produces 2.9 million Newton-meters of torque. The motor is being specifically designed to provide propulsion power for the next generation of Navy warships. A motor of this scale also has direct commercial application in large cruise ships and merchant vessels.

As an example, two 44-MW conventional motors are used to propel the famous Queen Elizabeth 2 cruise ship. These motors each weigh over 400 metric tons; the 36.5-MW HTS motor will weigh approximately 75 metric tons.

Chrysler ha reso nota la decisione di far ripartire a partire dal 29 giugno la
produzione in sette impianti attualmente fermi a causa della grave contrazione della domanda. Lunedì 15 giugno Chrysler aveva riavviato la produzione della Dodge Viper nell'impianto di Detroit a Conner Avenue. Gli impianti in cui la produzione sarà riavviata alla fine del mese sono quelli noti con i nomi di "Sterling Heights Assembly Plant", a Sterling Heights, in Michigan, dove si producono i modelli Chrysler Sebring e Dodge Avenger; di "Warren Truck Assembly Plant", a Warren, sempre in Michigan, dove si producono i Dodge Ram e i Dodge Dakota; di "St. Louis North Assembly Plant", a Fenton, nel Missouri (modello Dodge Ram); di "Toledo Supplier Park", a Toledo, in Ohio (modelli Jeep Wrangler e Jeep Wangler Unlimited); di "Brampton Assembly Plant", a Brampton, in Ontario, Canada (modelli Chrysler 300, Dodge Charger e Challenger); di "Windsor Assembly Plant", a Windsor, sempre in Ontario (modelli prodotti Chrysler Town & Country e Dodge Grand Caravan); e di "Toluca Assembly Plant", a Toluca, in Messico (modelli prodotti Dodge Journey e Chrysler PT Cruiser). Nel comunicato diffuso dalla società americana, si legge anche che a operare saranno anche le divisioni "Powertrain e Stamping" che riforniscono questi impianti di assemblaggio. Da segnalare che proprio lo scorso lunedì, 15 giugno, Chrysler aveva riavviato la linea di produzione della Dodge Viper, nell'impianto di assemblaggio di Conner Avenue,a Detroit, per la prima volta dal 30 aprile scorso, quando andò in amministrazione controllata. Tutti gli impianti di Chrysler Group saranno comunque chiusi - continua il comunicato - in occasione della pausa estiva che durerà due settimane, relativa alle settimane del 13 luglio e del 20 luglio. La ripresa della produzione in altri impianti di assemblaggio di Chrysler Group sarà resa nota più tardi.
(Fonte: www.ilsole24ore.com - 17/6/2009)

In our series of articles where we take a look at the worlds biggest electric vehicles in an effort to dispel the myth that EVs have to be low powered vehicles we've already looked at a 3650 hp dump truck, a 24,460 hp Bullet train and a 140,000 hp ship this week we'll look at Diesel electric hybrid locomotive.

Although the V12 Diesel in the GE Evolution Hybrid Locomotive is 'only' 4,400-horsepower, on a typical fully loaded coal train, for example, pulling 100 coal hoppers with 10,000 tons that stretched 2 kilometers (enough to keep a 1 GW coal fired power plant fueled for a single day), up to 5 such locomotive would be used giving a combined output of 22,000 hp with close to half a million newton meter (489,000 Nm) of starting torque from it's AC electric traction motors.

What sets the GE hybrid locomotive apart from the rest is while standard diesel electric locos burn off brake energy as heat through a large roof mounted resistor bank called a rheostat, the hybrid captures the energy dissipated during braking and store it in a series of large batteries. This stored energy can allow operators to draw an additional 2,000 horsepower when needed while reducing fuel consumption by as much as 15 percent and emissions by as much as 50 percent compared to most of the freight locomotives in use today.




The energy dissipated in braking a 207-ton locomotive during the course of one year is enough to power 160 households for that year. In fuel savings the recycling of energy through regenerative braking saves approximately 1 million gallons of fuel over its lifetime or approximately $2.50 million at $2.50 per gallon.

For the man who has everything, a swiss company called Code-X have developed a boat for maximum exclusivity that uses renewable energy combined with two Formula One spec motors. It's not your average speed boat that requires a low loader semi trailer to be transported on land, while any boat the comes standard with 2 x 710 hp Ilmore V10s is very impressive. Code-X combines those with 2 x electric motors and a deck lined with solar panels.

No specs are provided at all for the EV power system so we have no way of judging if they are anymore than novelty value but solar electric pleasure craft is something we are sure to see more of in the future.


Engines:
2 x electric engines
2 x Ilmor marine combustion engines MV10-710
Configuration : 90 degree V 10
Horsepower : 2 x 710 HP
Torque : 882 Nm @ 4800 rpm
Full throttle rpm range: 5400 - 6300
Capacity: 2 x 8.3 liters
Performance: 90 kn


Source of Energy:
Fossil fuel (2 tanks)
Solar-power

CODE-X

The chairman of automotive components giant Bosch says it will take more than a decade for Electric Vehicles to even “make a noticeable mark” on the world car market and the the internal combustion engine is likely to be "unchallenged in the next 20 years”.

Speaking at an automotive seminar at the company’s Boxberg research center near Stuttgart, Bosch chairman Dr Bernd Bohr says the company estimates that by 2015 electric car sales will account for just 500,000 units annually, from a car production total around 100 million units.

Improved and downsized turbo petrol and diesel engines, their efficiency boosted by as much as 50 percent over today’s designs, will remain the main motive power for cars for at least 20 years, and probably beyond, Bosch believes. They could only possibly be referring to potential fuel efficiency improvements as opposed to energy efficiency which is fairly fixed for an internal combustion engine.

However, Dr Bohyr does believes that electrically powered vehicles will eventually dominate based on simple efficiency grounds. For the oil equivalent of one kilowatt hour of power, today’s internal combustion engine delivers 1.5 to 2.5 km of range, he says, a figure that improves to about 3.2km in a diesel hybrid. Under the same conditions, an electric motor delivers about 6.5km of range.

The major hurdle for electric cars remains the weight and cost of their batteries, says Dr Bohr. Bosch is “working hard” to develop the lithium ion variety it believes has the best development potential for cars, through a recently-arranged joint venture with Samsung.

At present, says Dr Bohr, a li-ion battery that can propel a 1000 kg car for the 200-km range most buyers say they need weighs 250kg and costs around 17,000 Euros, far too much. Bohr is “very confident” that by 2015 it can cut weight by around 30 per cent and cost to by nearly half, figures it believes are approach acceptability for production cars.

Of course Bosch are pushing their own barrow here as they make both diesel and petrol direct injection systems that stand to benefit from a continuation of ICE dominance, they are not a Li-ion battery company.

Their biggest cash cow, ABS and ESP may also be under threat by the move to EVs as computer controlled independent wheel motors will make the use of electro-hydraulics to actively control vehicle dynamic safety systems obsolete.

BOSCH