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Electric Hybrid

Patrick14

Member
Good Morning!
Is anyone working on a hybrid propulsion System? For example Siemens Electric Motor downrated to 130kw, "small" 40 kWh battery and a Rotax, Limbach, Jaribu or similar to feed the battery
 
As I understand it (and someone correct me if I'm wrong) in hybrid autos, energy that is normally dissipated through braking, coasting down hills, etc. is converted to electrical energy for the batteries. Those opportunities generally wouldn't be available in an aircraft.

Now if someone could figure out how to convert the energy lost due to skin friction to electrical energy, we might be on to something.
 
a serial hybrid just means that the electrical power for the propulsion is made available by a second, in this case fuel burning piston, engine. The fuel engine could be much smaller and could run on cheap fuel in its most economic range .The Electric motor with its high torque could drive a large diameter slow turning propeller. 130 kW Motor, 40kwh buffer battery and a 120hp gasoline engine should do. As AVGAS prices are astronomically high over here and availability is uncertain for the future, i would highly appreciate this more efficient system, even if it would be more complex, expensive and heavier than the lycoming. Unfortunately its out of my first time builder capabilities. Did anyone try already?
Patrick

Ps please excuse the typos...
 
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Shocking...

Vie Gehts Patrick,
Two years ago I replaced the aging 2180CC VW engine in my Sonerai IIL with a new 1835CC VW (blueprinted specifically for aircraft). The engine builder had removed it from his Q2 in lieu of electric power.
His choice of power? The Electraflyer installation: http://www.electraflyer.com/index.php

I think EP is a viable alternative in the RV12 or maybe a new RV design yet to be engineered... Pipistrel is already flying an approved LSA down under....

Check this out: http://electro.aero/index.php/en/ne...alian-flight-of-electric-light-sport-aircraft

Tcheus!
Smokey
 
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Unfortunately electric power does not meet LSA parameters in the U.S.....

YET!
 
Welcome to VAF

Patrick, welcome aboard the good ship VAF:D

Good Morning!
Is anyone working on a hybrid propulsion System? For example Siemens Electric Motor downrated to 130kw, "small" 40 kWh battery and a Rotax, Limbach, Jaribu or similar to feed the battery

Why use an engine that is designed to directly power a propeller in this situation?

What you are proposing looks like this;

Aircraft engine->generator/alternator->battery->speed control->electric motor->propeller

You are adding weight, cost, complexity, and probably loss of efficiency throughout the system.

I would think it would make more sense to use a engine/generator package that is designed from the ground up to be such. Think Honda eu200i for example------light, cheap, light, hugely successful track record, runs for hours on very little gas. Obviously this particular generator is not enough to run the plane on its own, but I only cite it as an example of what seems to me to be a much better choice instead of the OP suggested setup.
 
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Hybrid

check out purepowerm.com

If this works out, it sure isn't a bad idea to have 10-15 min of flying time available in case of an engine stoppage, and have extra power on takeoff when needed....

Kurt
 
Hallo SmokeyRay,

thanks for the link. Sounds promissing. I think pure electric would unfortunetly not fit to the current design of the RV7 i am going to build. Batteries would be too heavy for 2hrs of flight at 100hp.:(

Hi Kurt,
thanks for the link! I never heard of them before. Sounds similar to what Thielert did a couple of years ago. Most probably a Mercedez Benz 4 cylinder diesel engine adjusted for aircraft use. I have contacted them to find out if:
a) it is aerobatic/inverted capable
b) recommended inflight adjustable propeller
c) pricing

Does anyone know somebody with experience on this system?
 
Hi Mike,

thank you for the quick reply!
Of course a system build for this purpose would be best. I just don´t know one yet.
I would need an engine -generator combo with at least 70 kw (~100hp) contious output to stay in the air and on top very slowy recharge the accumulators. e.g. Electric motor with 120kw at 10 minutes Take Off and Climb means 20 kWh of energy. 10 minutes generator at 70kw means 11kwh so after climb i would be 9kwh away from full. If an RV 7 stays during cruise in the air with 90hp (~55% of 160hp) it would take approximately 2hrs to recharge, which perfectly fits to my mission profile. Taking into consideration the losses for controller, charger, motor, heat and so on, 75kW continous would be more suitable and inverted capability would be perfect but not absolutely needed as the 15min aerobatics could be done pure electric.
 
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Lightweight, hi power, electric motors are fairly available. What I can't seem to find is a lightweight 125Kw generator. If someone can crack that nut the hybrid drivetrain will likely be a lot more feasible.

DEM
 
Gen

Go to the junk yard and get a motor out of a wreaked Prius engine and gen combo.
Bob
 
Silent!

Patrick,
I neglected to mention that one of my neighbors bought a Silent 2 Electro powered sailplane from your neck of the woods last year. He flies it regularly and I have to say, very impressive. The powerplant engineering is worth a look...
Cost, efficiency, sound, and tech-savvy. I like it...:)

http://www.alisport.com/?product=silent-2-electro-2

V/R
Smokey
 
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