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Is the Fisker Karma series hybrid or parallel?

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I think the Karma turned out to be at least in part a parallel hybrid.

Not so sure about that - I think someone may have mis-reported things.

10 Questions for the Karma’s Henrik Fisker Earth2Tech
Earth2Tech: The Fisker Karma will be a series hybrid like the Volt. Why did the company choose this technology as opposed to a parallel hybrid or an all-electric car? Henrik Fisker: We chose the plug-in hybrid technology because it brings you the best of both the gasoline engine and the pure electric. When you plug in our car everyday you then can go 50 miles on pure electric. The big difference to a normal hybrid is that the Karma will stay in pure electric and, therefore, zero emissions for the first 50 miles. The advantage over a pure electric car is that, just like a gasoline car, we have no range limitation. After having passed the 50 miles on pure electric, you can fill the car up at a gas station and go as far as you want, which is the ultimate freedom, which cars are about.
This was the article that may have gotten it wrong:
Fisker Reveals Production Version of Luxury Electric Car : Gas 2.0
As opposed to a plug-in hybrid like the much touted Chevy Volt, instead of a series hybrid sytem the Karma uses a parallel hybrid system — meaning it uses gas and electric power at high speeds in parallel using a common mechanical drivetrain.
Further evidence that it is in fact series not parallel:
Fisker Karma plug-in hybrid car to be unveiled at Detroit Auto Show
The sleek, low-slung Fisker Karma is a series (as opposed to parallel) hybrid, which means that only the electric motor is connected to the drive wheels. The gasoline engine only serves to drive the generator which charges the battery. The Karma is said by the manufacturer to have a top speed of 200 kph (125 mph) and a standing-start 0-100 kph (0-60 mph) of 5.8 seconds. Not bad for a car that is nearly 5 metres long and weighs over 2 tons.
From Fisker:
http://karma.fiskerautomotive.com/pages/karma
The Karma uses Q-DRIVE plug-in hybrid technology, developed exclusively for Fisker Automotive by Quantum Technologies. A fully-charged Karma burns no fuel for the first 50 miles. Venture further and the gasoline engine turns a generator to charge the lithium ion battery. Once the 50-mile electric range has been exceeded, the car operates as a normal hybrid vehicle.
The above seems slightly ambiguous. It says the gasoline engine turns a generator, but also says it acts as a "normal" hybrid. What does "normal" mean? I imagine some took that to mean parallel, but that is possibly a wrong interpretation.
 
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I am fairly sure Karma & Sunset are "Series" hybrids.

Detroit 2009: Fisker Karma S hardtop convertible unleashed - AutoblogGreen
Q-DRIVE®: POWERFUL TECHNOLOGY Exclusive to Fisker Automotive, Q-DRIVE® provides the best combination of power, efficiency and low emissions. The system is comprised of two 201hp electric motors powered by an advanced lithium-ion technology battery pack. A generator attached to a 260hp turbocharged 2.0-liter Ecotec® direct injection (D1) gasoline engine provides extended range capabilities.
Q-DRIVE® features two operating modes: Stealth Mode and Sport Mode. In electric-only Stealth Mode, drivers can travel emission free for up to 50 miles on a full charge from any 110-, 220- or 240-volt electric outlet. A total range of up to 300 miles is estimated in Sport Mode, which utilizes the efficient Ecotec® gasoline engine to turn a generator that powers two electric motors on the rear differential. A fully charged Karma can achieve an annual average of more than 100 miles per gallon.
My guess is that "Stealth" mode is slightly power limited due to battery pack output limits. If you enable "Sport" mode then the gas motor turns on sooner to supplement current from the pack with generator current to get full power from the dual eMotors. But I still don't think there is a mechanical linkage from the gas engine to the differential. (Please feel free to prove me wrong. I am trying to read between the lines here).
 
I agree TEG, I believe the parallel came only from a lack of understanding about the "Sport Mode".

This quote from from Fisker's website.

The Karma

The Karma's Q DRIVE configuration consists of a small gasoline engine that turns the generator, which charges the lithium ion battery pack, powering the electric motor and turning the rear wheels.

Stealth Mode
0-60 in 7.5 seconds (0-100 km/h 7.5 seconds) Top speed 95 mph (153 km/h)
Sport Mode
0-60 in 5.8 seconds (0-100 km/h 5.8 seconds) Top speed 125 mph (200 km/h)
Two Driving Modes: The driver will be able to select between two modes of driving. The first mode is Stealth Drive, which is the quiet economy mode for optimal relaxed and efficient driving. By flipping the second paddle behind the steering wheel, the car will switch to Sport Drive, which will access the full power of the vehicle.

Stealth mode is limited due to the maximum power available from the battery pack alone. With the engine generator unit running full electric power is available for maximum performance.
 
[ mods - can you consider moving all related posts to this topic? ]

As far as I know the Fisker Karma (and Sunset) are series hybrids where the gas engine only ever drives a generator and has no mechanical connection directly to the wheels.

There seems to be a long running rumor/mis-interpretation that it is, or can temporarily switch to "parallel" hybrid mode. I think this was started because Fisker touted their "sport" mode as offering full performance when the gas engine is running. This may not be a mechanical linkage, but rather more current available than the battery pack can supply on its' own. The Fisker cars have two large eMotors totalling around 400hp max, so they would need more current than even Tesla's much larger battery pack could supply. For this reason, I think they need gas engine spooled up to provide full eMotor power, but it is still "series" if it has to have all gas engine HP come through the generator.

Here are some articles that claimed (probably incorrectly) they are "parallel" hybrids:

24Nov2008:
Sympatico / MSN Autos (EN): Good Karma: Fisker picks GM Turbo engine to power its luxury plug-in hybrid
Because the Karma is a plug-in parallel hybrid
02Dec2008:
Fisker Reveals Production Version of Luxury Electric Car : Gas 2.0
The production Fisker Karma will have an all-electric range of 50 miles (80km), after which the gasoline engine kicks in and charges a lithium ion battery pack which in turn powers the car as a normal parallel hybrid.
...
As opposed to a plug-in hybrid like the much touted Chevy Volt, instead of a series hybrid sytem the Karma uses a parallel hybrid system — meaning it uses gas and electric power at high speeds in parallel using a common mechanical drivetrain.
11Dec2008:
Fisker Electric Plugin Car gets 100mpg: The Karma , really.. | The Karma Report.com
Yes I am not making it up, Fisker Automotive has designed a beautiful electric parallel hybrid plug in 4 door sports car.
Karma the Car. Fiskers New 4 Seater Electric Plugin Vehicle | Green Car Magazine
Fisker Automotive has designed a beautiful electric parallel hybrid plug in 4 door sports car
Fisker Karma Production Version Revealed - Gearlog
According to Gas 2.0, all else -- including Karma's parallel hybrid propulsion system -- remains as planned.
 
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Thanks, Doug. That is about as direct as we could have hoped to get this clarified.

Remaining question is if the "stealth" mode is performance limited because the battery pack can't output the full 300kW by itself (so it needs the ICE generator to be going at the same time)?

They seemed to have designed the Karma with the idea that you will use the ICE some of the time. (In other words, it is NOT just a low speed short range commuter car with range extender for emergencies... They don't want a "limp home" mode when the pack is low).

Volt on the other hand is more optimized for battery only operation, and may be more limited when you have run the pack down. (Volt never had aspirations to be a performance car anyways).

As with all PHEVs you will need to plug it in frequently if you want to maximize efficiency. Some small minority of owners might only ever "gas it up" and find that it is less efficient than a Prius that way.