20hp Electric Motor

[irm750]

I have been watching the development of electric paramotors with interest for some time but after many false starts and promises of imminent product launches it seems to have gone quiet on that front lately.

I'm seriously thinking about building my own, how hard can it be?

I have seen this motor and thought I'd share it on here to canvas any opinions or experience that you may have. It's only $300 and at 20hp allegedly has the equivalent power to a 100cc engine. I know that there are loads of other bits required to make a working paramotor but it looks to me like a good starting point?

http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=14427

Best regards,

Ian

[Guest]

Hi Ian,

I too have looked into this very motor.

Its the battery drain rate on full chat thats the problem.

It is CLOSE to doable though

SW

[alan_k]

Hi Ian,

That sounds like a good price for an electric motor

Have a look at http://www.agnimotors.com/home/index.ph ... &Itemid=60 for some interesting performance graphs. The motor weighs 11Kg

Cheers,

Alan

[mark77a]

Another (OK may need to be used in multiples)..

http://www.alebproducts.com/proddetail. ... d=brush008

Anybody have any news about what's going on at parajet and their electric paramotor ?

[Heard they have it upto 25Min at a weight of 19Kg .. which is VERY interesting]

[outkast]

big problem with electric motors is you are always working with diminshing returns, the more you use it the less power it has, unlike a petrol motor wich gives you the same output no matter how long you are flying.

electric motored paramotors will only be viable once the battery technology is suficant at a reasonable price and thats a while yet

[mark77a]

Yes - if you want to be up for hours, and do XC: like long range cars nothing beats the energy concentration and low costs, of petrol.

But, if like me, a 25min 'power on' is ok (and especially if lighter and a bit quieter) , then electrics are a fascinating option which can only get better.

[pete_b]

Horses for courses

There is a use for every thing, its just different people that use different things

[Guest]

I love the idea of an electric Paramotor and cant wait for battery technology to reach its potential and deliver an hour + of 'power' time.

SW

[eparaglider]

Hello, I working on electric paramotor project, and I have new items available in store for e-paramotor project: Electrical Motors (outrunner 15kWt to 25kWt, ESCs 350A to 450A for electric paramotor or hang glider projects: http://eparaglider.com/electric-paramot ... -for-sale/

At this time I working on RC store: http://epowerhobby.com

Business located in USA.

[Satti]

Hi all, 

For some strange reason this thread regarding Electric has gone dead ?? Anyone knows why ?

Currently there at least 5-6 paramotors of different capacities being sold on the internet. 

btw I have decided to go electric and this is the motor and ESC ( Electronic Speed Controller) that I intend to purchase off a mob called FREERCHOBBY.com in China

MP 15470 30kw 60kg Thrust Sensorless Motor for Drone /Paramotor – Dongguan Freerchobby Co.,Ltd 

FRC 500A 28S HV ESC brushless speed controller with USB program cable – Dongguan Freerchobby Co.,Ltd

There are of course more powerful choices of thrust up to 90 kg, however I am only 70kgs

My intention is to fly at least twice a month ( fingers crossed ) and no dreams of thermalling and cross country. I would be really happy if I can stay aloft for half an hour or more and land safely.

I haven't yet ordered  and paid for the stuff yet, and before I commit myself, I thought to ask around for some honest opinions. Please do share with your thoughts and I don't mind some harsh critique either.

happy and safe flying all you can post here or share with me on facebook Satti El Musafir

cheers guys

 

[Ganbatte]

I think the limited excitement behind electrics boils down to battery technology being just barely good enough right now. Openppg is close to shipping its batch 2 of the SP140 and hopes to make it a stocked item; if it were stocked today, I'd order one today, though with the small batteries only. 53# and 30 minutes nominal is just barely within the envelope of acceptable for some usage, but instant on/off and near zero maintenance are attractive, and that time/weight is competitive with lightly fueled gas motors now. Sadly, capacitors will have to improve about 10X to compete with lithium, but then offer near infinite service life and charge times limited by one's electrical outlet. If electrics got to dual motors with coaxial shafts, then varying the speed of  counterrotating props could replace or supplement weight shift... another interesting concept! But sadly not imminent.

[Blackburn Mark]

8 hours ago, Ganbatte said:

boils down to battery technology being just barely good enough

Ill second that
For all the advantages, it just doesn't add up to anything useful for the average pilot at this time.

Some of the excitement seems to come from novice or pre-flight "pilots" who get lured by the tech but fail to grasp the practicality of a 20min flight time. (not interested in claims of an hour+ flights if in reality means tickling the throttle in ideal temperature's and conditions... We all know there is OFTEN a gap twixt claim and reality when it comes to the sales blurb)

I would say that in practice, the bulk of desire settles into 2 hour flights with plenty of reserve (I get 4hrs + a reasonable reserve and I do use it reasonably often)... No real consideration for what is doing the pushing once airborne, as long as it is reliable and doing its job.... After all, for most, we want to explore the world from the air and shiny gear/posh tech is second to that  
 
 

[Ganbatte]

Well yes and no; new technologies find a niche, then propagate outwards from that first toehold on the market. Witness early cell phones that cost $1 a minute for talk time, and now.

A nominal 30 minutes (maybe 20 real world) is enough for short range putter-abouts, and launch/land practice. Also sufficient for people who use just enough power to find a thermal, then get back home. Electrics have the virtue of running only when you want them to; no issue with restarting in flight; just throttle up when you want power, release to turn off. And the negligible maintenance aspect is unique, compared to our cranky 2-strokes. No landlord issues for apartment dwellers looking for a place to store their fuel-dependent devices, either.

[Blackburn Mark]

4 minutes ago, Ganbatte said:

(maybe 20 real world) is enough for short range putter-abouts

That's the problem, no amount sales spiel is going to butter over that debilitating fact.
The whole world is waiting for hover boards and better batteries so its not like the issue isn't front and center for all to see.
When batteries have four times the current energy density, are affordable and are safe at that, Joe Average PPG pilot will have a battery option that somewhat competes with his "cranky 2-stroke"... maybe not the four strokes though  

We are in the "niche" right now... The take-up is very poor and until batteries improve, I cant see that changing.
Your phone comparison is more a cost/scale progression.
Electric PPG's don't have that problem, all the stars are already lined up but the one.
We simply piggyback on the already existent MASSIVE demand for batterie's and motors... Our problem is a technology one and the technology isn't quite there yet and when it is, it will be debilitatingly expensive for the first 5~10 years and that is if Joe Public is allowed to own such batteries.

[alan_k]

There is a shed load of research and development going into alternative battery technologies atm.

I am sure the greater energy density will come, but don't hold your breath (for longer than 20 minutes ).

[Bob27]

12 hours ago, alan_k said:

don't hold your breath (for longer than 20 minutes

You don't need to wait. The Exomo, Paracell, and OpenPPG SP140 can all handle a realistic 40+ minutes with some reserve and in perfect conditions over an hour. Or if you want to wait, I am currently helping another company who is developing a new foot launch E-PPG that is looking to have a peak flight times around 75+ minutes.

[Blackburn Mark]

6 hours ago, Bob27 said:

You don't need to wait.

I think Alan was being hyperbolic... Pretty sure 75 mins is still a little short for most of us.
I'm sticking with my "two hours plus reserve" before it starts making a dent in the market.
The current prices for such items are not much incentive either ($7320) plus the instability of small scale would be a concern for long term after sales care.
 
I'm sure things will improve on the battery front at some point but its pretty brave and risky for manufacturers and buyers at this point  

 

[Bob27]

You definitely have a point. At this point I don't believe electric is for most people, but I think it's perfect for a few people. 

The sacrifice that comes with electric is a much more limited flight time, it requires ~4 hours to charge back up, and it doesn't go well with water(we are also trying to fix this)

But, electric has a ton of benefits include a much quieter cruise, silent and more efficient glide, operating cost as low as 55 cents per hour, no mixing fuel, no maintenance, no vibration, very linear throttle control, no oily messes, the paramotor will last longer, and a lot more. 

I imagine electric being perfect for people coming from paragliding that won't use very much flight time and don't like the loud engine noise, those who are not mechanically inclined or have time to do all the maintenance on a gas paramotor, people who fly in more noise sensitive areas, those who can go fly once a week on the way home from work but only have 45 minutes anyway, or those who live on a property where they often fly shorter flights from their house. So for me personally, electric would be perfect.

[Blackburn Mark]

1 hour ago, Bob27 said:

quieter cruise, silent and more efficient glide, operating cost as low as 55 cents per hour, no mixing fuel, no maintenance, no vibration, very linear throttle control, no oily messes, the paramotor will last longer, and a lot more. 

That's a list of ancillary properties and some of those are a stretch.
Mosfets don't last forever and are a pretty nasty job to replace, The prop is never going to allow us to fly without ear protection anyway, maintenance I will tentatively grant (depends on how hard you are pushing those mosfets)  Vibration (or lack of) would be a winner,  not sure where the more "efficient" glide comes from, especially if you have low cogging motor ~ freewheeling prop against a clutch-less IC motor.

The big one for me would be the convenience of flicking a switch and being ready to go... Its a small thing but if there is one thing that get on my tits, its prepping for launch... In free-flight, its bad enough but with power you can times that by four... with electric, maybe two or three  

I don't mean to dampen anyone's enthusiasm too much, I am somewhat responding to the question as to why this thread died... We are waiting for the tech to catch up! 

[Bob27]

1 hour ago, Blackburn Mark said:

Mosfets don't last forever and are a pretty nasty job to replace

They don't need to. If an electric lasts twice as long as the best gas paramotors, they only need to last 100 hours. That's not hard as long as you get a quality motor with reasonable phase currents and a good motor controller.

1 hour ago, Blackburn Mark said:

prop is never going to allow us to fly without ear protection anyway

Prop noise is primarily based off tip speed. So if you can get a 140cm high pitch 3-blade spinning at a low rpm you can significantly reduce prop noise for a given thrust. It will increase torque, but we could possibly bring the noise low enough that with say a 10kw power limit it would be quiet enough that hearing protection would not be needed.

 

2 hours ago, Blackburn Mark said:

 

2 hours ago, Blackburn Mark said:

not sure where the more "efficient" glide comes from, especially if you have low cogging motor ~ freewheeling prop against a clutch-less IC motor.

Most motor controllers have a capabilities such that they go into a regenerative breaking mode such that when the throttle is not applied the motor will come to a stop rather than freewheeling. This would allow for a glide more efficient than any paramotor engine with a clutch.

[Blackburn Mark]

Ok... Ill play
 

9 minutes ago, Bob27 said:

they only need to last 100 hours. That's not hard

50 two hour flights, I get the feeling Mosters do quite a bit better than that... Baileys, even more so... That's if we compare a mosfet referb with a head/piston swap, not an unfair comparison, both well and truly ground you and cost hard cash  
An over-engineered ESP may last for decades of hammering but my experience with off the shelf ESP's is hit and miss even when I have vastly under run them, they can die.
Its hard to speak to the problem with such a small sample size but controller issues are often "hot" topics when i have followed experiments with electric flight.
Ill grant you that there will be less need for tinkering and no need to run the classic bead through a cracked Moster exhaust but that can be done between flights  
 

11 minutes ago, Bob27 said:

So if you can get a 140cm high pitch 3-blade spinning at a low rpm you can significantly reduce prop noise for a given thrust.

That would take some doing... I would think higher pitch/broader chord would give away some aerodynamic efficiency and static thrust for a given diameter.
These are things that could be done with an ordinary IC powered paramotor but we don't see it... why is that?
The Atom 80 seems way quieter than its prop.

I suspect a lot of paramotor prop noise is caused by it cutting through all the turbulent air caused by the frame, head legs etc... Common with pushers apparently.
Torque would only increase as a fraction of and in proportion to the loss of efficiency (not much in terms of frame torque but unlikely to be insignificant in terms of flight time)... Or are you talking about the motors need for "more torque"?

If i had a brushless with enough torque to spin a high pitch prop, I would slap a 160cm two blade on it instead... Probably be quite (ish), more efficient and give another 10% static thrust

 

[Ganbatte]

I suspect that if we got merely 2:1 energy density vs current batteries, the SP140 would start flying off the shelf (no pun intended).

Even if electrics appealed to only 10% of the market, that'd be a lot. Get a few extra batteries and they'd be perfect for schools; not necessarily all their stock, but one electric in the stable.

Biggest operating cost right now is amortization of the batteries, which is largely a function of their cost.

[Bob27]

1 hour ago, Ganbatte said:

I suspect that if we got merely 2:1 energy density vs current batteries, the SP140 would start flying off the shelf (no pun intended).

They already are. All 40 units of batch one where pre-ordered months ago and they haven't even shipped yet. There are now at least a dozen people waiting to preorder the batch two sp140 and for everyone who pre-ordered there is at least one more person that has the money ready, but is waiting to to buy when they are in stock

 

1 hour ago, Blackburn Mark said:

50 two hour flights

Meant to say 1,000 hours. Apparently one zero is a big difference. That being said the Average gas PPG only lasts 500 hours with engine rebuilds an proper maintenance, so even if the electric components are good for 1,000 hours it would be a big improvement.

 

1 hour ago, Blackburn Mark said:

 

4 hours ago, Bob27 said:

So if you can get a 140cm high pitch 3-blade spinning at a low rpm you can significantly reduce prop noise for a given thrust.

That would take some doing... I would think higher pitch/broader chord would give away some aerodynamic efficiency and static thrust for a given diameter.
These are things that could be done with an ordinary IC powered paramotor but we don't see it... why is that?

It doesn't give away almost any efficiency for an ICE paramotor but for an electric it's actually more efficient as the winding in the lower KV motors tends to be about 3-5% more efficient. 

Now these could be done with an ordinary ICE paramotor. As mentioned before the biggest reason it's not done is that in increases torque (by about 30%), it often requires a bigger prop which may not fit in a standard paramotor frame, and other than noise there isn't really any advantage for an ICE paramotor.

 

2 hours ago, Blackburn Mark said:

I suspect a lot of paramotor prop noise is caused by it cutting through all the turbulent air caused by the frame, head legs etc... Common with pushers apparently.

a tiny portion of noise will come from this, but it's not that much. About 80 percentage of all propeller noise comes from the tip, so if you really want to reduce noise you must prioritize this. The only way to reduce this noise is to reduce the speed that the tip of the prop is traveling.

[Ganbatte]

Actually, prop noise has been addressed by the gyrocopter people by bending the tip of the prop 90 degrees (making it reach back further from the netting, if you used it on a paramotor). That breaks the tip vortex and greatly reduces noise. No such props I know of for ppg, and the ones for gyros are crazy expensive, but the design/test work has been done.

If the sp140 were a stocked item, I'd have one en route as we speak. But I'm not willing to wait until fall.

 

[Bob27]

This is true, modified tips can significantly reduce propeller noise and slightly improve efficiency. I have personally modified the tips of propellers on radio control helicopters, drone, and airplanes and have had success with reducing noise. I would love to see propeller manufactures like helix and e-props at least test some new tips of various angles and shapes, but I can see a few reasons why they may not be practical for PPG use.