[Cad] [motors, power ee, & evs] (Siemens) Electric aircraft: World-record (50kg:260 kW contiunuous) electric motor makes first flight. also, electric dirigibles from 1885?!

Tue Jul 12 20:27:44 EDT 2016

The approach is to have a closed shell around the stator such that the oil
does not enter the airgap. This increases the airgap by a portion of a
millimeter. This will have some variable effect based on the type of magnet
and the machine design.

Usually something akin to a transformer oil is good to use. I have used
synthetic transformer oils to good effect. Just don't light your engine on
fire...

--damon

On Tue, Jul 12, 2016 at 5:16 PM, nk <nkirkby.nk at gmail.com> wrote:

> Damon,
> direct oil cooling on the motors you worked on - is the rotor floating in
> oil and making viscous losses in the air gap?
> or oil mist?
>
> Nkirkby
> On Jul 12, 2016 2:43 PM, "damon vanderlind" <damonvl at gmail.com> wrote:
>
>> Sorry 'bout that.
>>
>> GA: general aviation
>>
>> Cheating: just a matter of price. If it's really expensive to use these
>> materials maybe you don't want them for your electric aircraft. Like, why
>> aren't airliners 100% titanium? It's a great material, but expensive to buy
>> and machine
>>
>> 4 kW: just to point out you can do OK with avoiding the rare materials. I
>> worked on some 120 kW 32 kg motors (~4 kW/kg), that also did 1000 N*m
>> torque, without using anything particularly exotic. They were also direct
>> oil cooled, which the Siemens motors are.
>>
>> On Tue, Jul 12, 2016 at 11:39 AM, Nancy Ouyang <nancy.ouyang at gmail.com>
>> wrote:
>>
>>> wtf is GA
>>> why is it cheating to use crazy materials / power for first-in-class
>>> motor, &
>>> are you giving the example of 4 kw to contrast with their 5.2 kw
>>> techiniques, or to ...?
>>>
>>> if people write lengthier emails, it will help silly me understand what
>>> you are talking about <3
>>>
>>>
>>> ~~~
>>> my personal blog <http://www.orangenarwhals.com>, orangenarwhals
>>>
>>> On Tue, Jul 12, 2016 at 2:33 PM, damon vanderlind <damonvl at gmail.com>
>>> wrote:
>>>
>>>> The batteries aren't that bad... people just need to stop caring if
>>>> they can fly 500 miles.
>>>>
>>>> Siemens kind of cheats for their motors, though I think they are very
>>>> nice. They use hyperco 50 steel and really high switching frequencies. For
>>>> now, it prices the devices outside of GA even.  4 kw/kg can be built very
>>>> cheap, without rare materials and 1000 hours of wire edm time.
>>>>
>>>> Cheers
>>>> --damon
>>>>
>>>> On Tue, Jul 12, 2016 at 7:16 AM, Josh Vekhter <vekhterjr at gmail.com>
>>>> wrote:
>>>>
>>>>> Hmm, perhaps electric planes would actually be a reasonable
>>>>> application of that crazy aluminum galium thang the Marines are working on?
>>>>>
>>>>> Certianly makes more sense on an infrastructure level than fuel cell
>>>>> cars.
>>>>>
>>>>> Energy density of the fuel is supposed to be very good, idk anything
>>>>> about how much a 100 kw hydrogen fuel cell would weigh.
>>>>>
>>>>> Could always make hindenburg 2.0 :P.  Fuel could generate lift!
>>>>> On Jul 12, 2016 8:05 AM, "Lochie Ferrier" <lochieferrier at gmail.com>
>>>>> wrote:
>>>>>
>>>>>> Regardless of motor advances, batteries will still be primary issue
>>>>>> due to the mass fraction they need to take up. Even with a major
>>>>>> improvement in aero (co-flow airfoil
>>>>>> <http://www6.miami.edu/acfdlab/publications/AIAA-2015-0772.pdf>, or
>>>>>> BLI <http://web.mit.edu/drela/Public/N+3/Uranga2014_compressed.pdf>),
>>>>>> the L/D is still nowhere near what it needs to be for airliners, which are
>>>>>> majority of aviation emissions. This is where the whole Musk
>>>>>> electric jet <https://en.wikipedia.org/wiki/Musk_electric_jet> thing
>>>>>> gets very dodgy, or just beyond what we think is possible atm. To go cross
>>>>>> country at 600 Wh/kg, you need a L/D of 30, for something that is *supersonic.
>>>>>> *Play around with the numbers
>>>>>> <http://web.mit.edu/lochie/www/erange/main.html>, and you'll
>>>>>> hopefully see what I mean.
>>>>>>
>>>>>> There's very little way of getting around the fact that batteries are
>>>>>> approximately 100x heavier than kerosene on energy basis.
>>>>>>
>>>>>> On Tue, 12 Jul 2016 at 18:46 Nancy Ouyang <nancy.ouyang at gmail.com>
>>>>>> wrote:
>>>>>>
>>>>>>> sweet pdf, though lol loweffort response :p yes ofc batteries
>>>>>>>
>>>>>>> I believe the PDF is 2012 (why oh why don't people put date writtens
>>>>>>> or at least year written in their documents)
>>>>>>>
>>>>>>> The few electric motors available toda*y for aircraft propulsion *have
>>>>>>>> a power output of *less than 100 kW*. Large electric motors are
>>>>>>>> also used in trains, ships and submarines, but here the mass is less
>>>>>>>> important. Today it seems to be possible to build electric motors having a *specific
>>>>>>>> mass of about 2 to 4 kW/kg*. This compares favorably with the
>>>>>>>> specific mass of larger turboshaft and turbofan engines at cruise power
>>>>>>>> (see Figure 13 and Figure 14). *Future developments* may extend
>>>>>>>> the range of electric motors to values of *up to 8 kW/kg*, but
>>>>>>>> there is a strong need for the development of lightweight electric motors,
>>>>>>>> specifically designed for application in aircraft.
>>>>>>>>
>>>>>>>
>>>>>>> so this gives context to why siemen's motor is cool.
>>>>>>>
>>>>>>> 260 kW / 50 kg =* 5.2 @ 260 kW* or roughly *orange* circle:
>>>>>>>
>>>>>>> [image: Inline image 1]
>>>>>>> pg 12
>>>>>>>
>>>>>>> *does anyone know what the comparable previous weight would be
>>>>>>> before this motor? *this one is 50kg &  if this is a lot less than
>>>>>>> before, it's just another notch in reducing weight to make weightspace for
>>>>>>> battery packs perhaps.
>>>>>>>
>>>>>>>
>>>>>>> Range sensitivities Equation 11 shows that in order to achieve
>>>>>>>> maximum range for a given aircraft mass A lightweight aircraft is more
>>>>>>>> sensible to a change in mass than a heavy aircraft.
>>>>>>>
>>>>>>>
>>>>>>> I love their *"let's think through how we'd make this work" thought
>>>>>>> experiment* section:
>>>>>>>
>>>>>>> Applying this simulation model to a specific aircraft allows
>>>>>>>> determining the possible performance and the technology improvements
>>>>>>>> required to achieve the desired results
>>>>>>>
>>>>>>>
>>>>>>> The range of the original aircraft with 32 passengers is about 1200
>>>>>>>> km. With a reduced payload of 28 passengers the maximum range is
>>>>>>>> approximately 2200 km
>>>>>>>
>>>>>>>
>>>>>>> Using current (2012) technology this aircraft would reach a range of
>>>>>>>> 202 km. The flight time would be about 40 minutes. Cruise speed would be
>>>>>>>> about 300 km/h. If an additional reserve of 30 minutes for holding at the
>>>>>>>> destination airport would have to be considered, the practical range would
>>>>>>>> drop to 50 km.
>>>>>>>
>>>>>>>
>>>>>>> The next modification would reduce the empty mass of the aircraft by
>>>>>>>> 20%. This would require introducing extreme lightweight design features
>>>>>>>
>>>>>>>
>>>>>>> This step improves the battery technology by doubling the mass
>>>>>>>> specific energy * E . *Such an improvement is quite well possible
>>>>>>>> with future development of Li-S battery systems within the next 15 years*.
>>>>>>>> This modification would double the range to 711 km so that it at least
>>>>>>>> comes into the order of the kerosene based aircraft. Nevertheless, there is
>>>>>>>> still a factor of 3 in range missing. In order to achieve the range of the
>>>>>>>> original aircraft, the battery technology would have to be improved by this
>>>>>>>> factor, i.e. a factor of 6 compared to todays (2012) technology.
>>>>>>>
>>>>>>>
>>>>>>> Furthermore new infrastructure to replace and recharge the batteries
>>>>>>>> on each airport would be required to make such an aircraft feasible
>>>>>>>
>>>>>>>
>>>>>>> Comparing the payload-range characteristics of the baseline
>>>>>>>> turboprop aircraft and the battery powered electric aircraft shows that
>>>>>>>> trading payload for fuel respectively battery has a very beneficial effect
>>>>>>>> in case of kerosene because of its high specific energy
>>>>>>>
>>>>>>>
>>>>>>>> If, on the other hand, the final extremely modified aircraft
>>>>>>>> 328-LBME2 would be equipped with a current turbo-prop engine, its fuel
>>>>>>>> consumption would be as low as 1.5 liters per passenger per 100 km, which
>>>>>>>> is about half that of the baseline aircraft.
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> (This last stat is mostly due to how light and dragless the author's
>>>>>>> thought-experiment is, I think.)
>>>>>>>
>>>>>>> Thanks,
>>>>>>> --Nancy
>>>>>>>
>>>>>>> ~~~
>>>>>>> my personal blog <http://www.orangenarwhals.com>, orangenarwhals
>>>>>>>
>>>>>>> On Tue, Jul 12, 2016 at 2:48 AM, Lochie Ferrier <
>>>>>>> lochieferrier at gmail.com> wrote:
>>>>>>>
>>>>>>>> The batteries though. The batteries are what makes it super hard
>>>>>>>> <http://www.mh-aerotools.de/company/paper_14/MP-AVT-209-09.pdf>.
>>>>>>>>
>>>>>>>> On Tue, 12 Jul 2016 at 16:31 Nancy Ouyang <nancy.ouyang at gmail.com>
>>>>>>>> wrote:
>>>>>>>>
>>>>>>>>> www.siemens.com/press/electric-aircraft
>>>>>>>>>
>>>>>>>>> *"This is the first time that an electric aircraft in
>>>>>>>>>> the quarter-megawatt performance class has flown."*
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> https://www.youtube.com/watch?v=fiu8TFnXYFY
>>>>>>>>>
>>>>>>>>> In a big leap for the electrification of aviation, an Extra
>>>>>>>>>> Aircraft aerobatic plane performed its maiden flight with an electric
>>>>>>>>>> powertrain. The crucial component was a world record motor from Siemens.
>>>>>>>>>> Weighing a mere 50 kilograms, the motor has an output of 260 kilowatts,
>>>>>>>>>> resulting in an unparalleled power-to-weight ratio.
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Datasheet:
>>>>>>>>> http://www.siemens.com/press/pool/de/feature/2015/corporate/2015-03-electromotor/factsheet-erstflug-weltrekordmotor-d.pdf
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> https://transportevolved.com/2016/07/08/siemens-showcases-brand-new-electric-motor-thats-super-light-super-powerful-and-perfect-for-electric-airplanes/
>>>>>>>>>
>>>>>>>>>> Of course, electric motors have long been used in model planes,
>>>>>>>>>> but their use outside the 1:14th scale aeromodelling arena has
>>>>>>>>>> been somewhat limited due to the mechanics of making a sufficiently large,
>>>>>>>>>> powerful, & lightweight electric motor. And while we’ve seen some very
>>>>>>>>>> successful electric planes take to the sky, most have been custom-made,
>>>>>>>>>> super-lightweight affairs which while impressive, have yet to make their
>>>>>>>>>> mark on a wider scale.
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Many of the benefits of electric motive power for aircraft are
>>>>>>>>>> ones that any EV driver will be familiar with: quieter, lower maintenance,
>>>>>>>>>> greater efficiency. Benefits that are shared with the community too in this
>>>>>>>>>> case – as with increasing air travel areas around airports have become
>>>>>>>>>> increasingly polluted – both by noise and by noxious residues from burning
>>>>>>>>>> fossil fuels.
>>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>> But there are also other benefits that are deeply exciting for
>>>>>>>>>> aeronautical engineers and pilots.
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>> Unlike fossil fuel powered engines, electric motors really don’t
>>>>>>>>>> care which way is up. They operate the same upside-down as they do the
>>>>>>>>>> right way up — they don’t stall and fuss with fuelling issues when you turn
>>>>>>>>>> them over. They also perform the same at 40,000 feet as they do at 4 feet.
>>>>>>>>>> Traditional engines require complex mixture and timing adjustments to keep
>>>>>>>>>> them performing well in the thin atmosphere in which they spend much of
>>>>>>>>>> their lives.
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> about the airplane,
>>>>>>>>>
>>>>>>>>>> Based on a thoroughly modern, but not deeply exceptional
>>>>>>>>>> structure – with a mixture of a steel fuselage and carbon fibre wings, the
>>>>>>>>>> Extra is itself a popular aerobatic model
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>> The Extra 330LE, which weighs nearly 1,000 kilograms, serves as a
>>>>>>>>>> flying test bed for the new propulsion system. As an aerobatic airplane,
>>>>>>>>>> it's particularly well suited for taking the components to their limits,
>>>>>>>>>> testing them and enhancing their design.
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> the future
>>>>>>>>>
>>>>>>>>>> Electric drives are scalable, and Siemens and Airbus will be
>>>>>>>>>> using the record-setting motor as a basis for developing regional airliners
>>>>>>>>>> powered by hybrid-electric propulsion systems. "By 2030, we expect to see
>>>>>>>>>> initial aircraft with up to 100 passengers and a range of around 1,000
>>>>>>>>>> kilometers," explained Anton.
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> I love this anecdote about intelligent analysis tools in CAD. (*hi
>>>>>>>>> cad-discuss, that's why you're cc'd :]* )
>>>>>>>>>
>>>>>>>>> The end-shield for the motor, for example, was analyzed using a *software
>>>>>>>>>> package* that divided the component into over 100,000 elements,
>>>>>>>>>> each of which was individually further stress-analyzed and subject to*
>>>>>>>>>> iterative improvement loops.* Eventually, the custom software
>>>>>>>>>> spat out a filigree structure that weighs 4.9kg instead of the 10.5kg from
>>>>>>>>>> the previous design.
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> more about the motor
>>>>>>>>> http://phys.org/news/2015-04-world-record-electric-motor-aircraft.html
>>>>>>>>>
>>>>>>>>> Siemens researchers have developed a new type of electric motor
>>>>>>>>>> that, with a weight of just 50 kilograms, delivers a* continuous
>>>>>>>>>> output of about 260 kilowatts – five times more than comparable drive
>>>>>>>>>> systems.* The motor has been *specially designed* for use in
>>>>>>>>>> aircraft. Thanks to its record-setting power-to-weight ratio, larger
>>>>>>>>>> aircraft with *takeoff weights of up to two tons* will now be
>>>>>>>>>> able to* use electric drives for the first time.*
>>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>> New simulation techniques and sophisticated lightweight
>>>>>>>>>> construction enabled the drive system to achieve a unique
>>>>>>>>>> weight-to-performance ratio of five kilowatts (kW) per kilogram (kg). *The
>>>>>>>>>> electric motors of comparable strength that are used in industrial
>>>>>>>>>> applications deliver less than one kW per kg. The performance of the drive
>>>>>>>>>> systems used in electric vehicles is about two kW per kg.* Since
>>>>>>>>>> the new motor delivers its record-setting performance at rotational speeds
>>>>>>>>>> of just* 2,500 revolutions per minute, it can drive propellers
>>>>>>>>>> directly, without the use of a transmission.*
>>>>>>>>>>
>>>>>>>>>> In the next step, the Siemens researchers will boost output
>>>>>>>>>> further. "We're convinced that the use of hybrid-electric drives in
>>>>>>>>>> regional airliners with 50 to 100 passengers is a real medium-term
>>>>>>>>>> possibility," said Anton.
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> this might be what the motor looks like? not sure
>>>>>>>>> https://youtu.be/j3cNLsN-eCM?t=31s
>>>>>>>>> [image: Inline image 1]
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> about the Siemens and electric dirigibles (?!)
>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Siemens current motor is sufficient to power a small 4-seater
>>>>>>>>>> aircraft by itself. Indeed, it would be “quite racy” suggest Siemens in
>>>>>>>>>> that application. And Siemens is keen to point out that the motor is *nearing
>>>>>>>>>> the power requirements for small regional airliners. *Of course
>>>>>>>>>> if anyone would know about aeronautical electric motors it really ought to
>>>>>>>>>> be Siemens, given that it was its electric motor that (back in 1881) powered
>>>>>>>>>> the *first electric dirigible*
>>>>>>>>>> <https://archive.org/details/lesballonsdirig00tissgoog>*.*
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Also check out this amazing scan of an* 1885 book about electric
>>>>>>>>> dirigibles*. (archive.org's ebook software is on-point!)
>>>>>>>>> https://archive.org/details/lesballonsdirig00tissgoog
>>>>>>>>>
>>>>>>>>>> Dirigibles: application of electricity to air navigation
>>>>>>>>>
>>>>>>>>> by Gaston Tissandier
>>>>>>>>>> Published 1885
>>>>>>>>>> Book digitized by Google from the library of the University of
>>>>>>>>>> Michigan and uploaded to the Internet Archive by user tpb.
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Thanks,
>>>>>>>>> --Nancy
>>>>>>>>>
>>>>>>>>>    -
>>>>>>>>>
>>>>>>>>>
>>>>>>>
>>>>
>>>
>>
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