Search found 96 matches

by avandalen
Mar 04 2011 4:59pm
Forum: Motor Technology
Topic: Hub motor tuning
Replies: 4
Views: 1441

Re: Hub motor tuning

Miles, thanks for the Motor Excellence link. I have requested the factory for information! :D
by avandalen
Mar 03 2011 2:45pm
Forum: Motor Technology
Topic: Front wheel hub motor
Replies: 2
Views: 912

Re: Front wheel hub motor

Hi Dlogic, Can I help you with my solution? For my solar bike I will use the hub motor Q-F-85SX, 250W 1.7kg max. 82% efficiency. The ebike itself should weight about 14kg totally. I simulated this hub motor in Excel as mid drive motor, it has no benefits… See all here: http://www.avdweb.nl/ Albert...
by avandalen
Mar 03 2011 12:03pm
Forum: Motor Technology
Topic: Hub motor tuning
Replies: 4
Views: 1441

Hub motor tuning

I tried to make an overview of all parameters that are available to tune a hub motor. The goal is to increase the efficiency and power of a hub motor. Formulas are derived to show the relationships. The challenge is to build an efficient (> 90% ) and light (< 2kg ) hub motor. http://www.avdweb.nl/so...
by avandalen
Feb 21 2011 1:55pm
Forum: E-Bike Build Threads / Photos & Video
Topic: My solar bike
Replies: 56
Views: 9693

Re: My solar bike

Hi Avandalen, When you say "the PV panel voltage is much lower"do you mean no-load? If it's the case, this is bad... If the no-load voltage drop so hard, it means that you are really far away to extract anything from your cells. At shadow the voltage is much lower, it depends on how many groups of ...
by avandalen
Feb 09 2011 5:32am
Forum: E-Bike Build Threads / Photos & Video
Topic: My solar bike
Replies: 56
Views: 9693

Re: My solar bike

mmm :-/ What kind of battery chemistry are you intending to use? I fear that the battery won't like it at all. Do you use a BMS? if it's the case I do think it will go crazy because of the voltage's difference between cells. If not, you will more than probably have shitty performances and short cel...
by avandalen
Feb 08 2011 2:28pm
Forum: E-Bike Build Threads / Photos & Video
Topic: My solar bike
Replies: 56
Views: 9693

Re: My solar bike

This means that you don't want to recharge them during the trip? Gruß, H. Hi The panels are loaded during the trip (and discharged) and the MPPT charger switching between the two panels goes automatically, say every 5 minutes.The panels are loaded during the trip (and discharged) and the MPPT ch...
by avandalen
Feb 07 2011 10:55am
Forum: E-Bike Build Threads / Photos & Video
Topic: My solar bike
Replies: 56
Views: 9693

Re: My solar bike

dodjob wrote:Hi Avandalen,
Most of the MPPT I know, are only bucks (drop down).
Gruß,
H.
Hi
My solution is to split the battery into two batteries of 18V in series. The two 18V batteries are charged alternately (with a relays) . Thus I can use a MPPT ~ 30V to 18V.

Albert
by avandalen
Feb 07 2011 7:47am
Forum: E-Bike Build Threads / Photos & Video
Topic: My solar bike
Replies: 56
Views: 9693

Re: My solar bike

:-) For instance the MPPT charger we are using are accepting up to 100V Uopen for the little 250SMR. Hope this helps! Gruß, H. Hi dodjob, I'm definitely use a MPPT. In total there are 60 solar cells in series for about 30V input or less (depends on the shade). The battery is 36V. What for MPPT d...
by avandalen
Jan 28 2011 11:29am
Forum: Battery Technology
Topic: Rechargeable battery comparison table WIKI
Replies: 0
Views: 356

Rechargeable battery comparison table WIKI

Who can help complete this battery-comparison-table wiki table?

Image

It is a public wiki for everyone to use.

http://www.avdweb.nl/mediawiki/index.ph ... ison-table
by avandalen
Jan 24 2011 5:49am
Forum: E-Bike Build Threads / Photos & Video
Topic: My solar bike
Replies: 56
Views: 9693

Re: My solar bike

Hi Albert, I have just fragile raw cells and will make my own panels. I want to build them tough enough to handle dings from small rocks on the road. For one application, I'd like to make one tough and strong enough to walk or sit on if possible, which is one reason some curve is required...for far...
by avandalen
Jan 23 2011 5:03am
Forum: E-Bike Build Threads / Photos & Video
Topic: My solar bike
Replies: 56
Views: 9693

Re: My solar bike

Hi John, What do you mean, I don't understand, the varnish is on top of the epoxy? Have you made your own PV panel? Thanks for the tip, I shall consider a clear marine varnish also. I am currently testing encapsulations. As you can see at my site, batteries are really needed! I use the bike only fo...
by avandalen
Jan 22 2011 5:07pm
Forum: E-Bike Build Threads / Photos & Video
Topic: My solar bike
Replies: 56
Views: 9693

Re: My solar bike

I have calculated the PV panels air drag. The result of the calculation is an air drag of 3W at 20km/h. See here: http://www.avdweb.nl/solar-bike/solar-panels.html The drag calculation is correct for a flat plate that is absolutely edge-on to the apparent wind at all times, but pitch it by just a d...
by avandalen
Jan 22 2011 5:04pm
Forum: E-Bike Build Threads / Photos & Video
Topic: My solar bike
Replies: 56
Views: 9693

Re: My solar bike

Doesn't seem very practical if it sits in the garage over 300 days a year. Is this just a project to see what you can make? Hi GrayKard The solar panels can be dismounted quickly so I can use the bike also when there is no sun. As a practical test try riding the bike around with some thin plywood t...
by avandalen
Jan 22 2011 10:59am
Forum: E-Bike Build Threads / Photos & Video
Topic: My solar bike
Replies: 56
Views: 9693

Re: My solar bike

Hi there! First, Happy new year! :-) Your panels weight only 1.1Kg/piece (!!) Daaamn!! I have two 120W monocristallin panel at home and they weight 16Kg... both O_o' Don't you need a frame for them or a protection in order to avoid any damage? (yes I'm very surprised of the weight :-) ) Did you mak...
by avandalen
Jan 01 2011 9:01am
Forum: E-Bike Build Threads / Photos & Video
Topic: My solar bike
Replies: 56
Views: 9693

Re: My solar bike

140 watts of what voltage? No way even 12v. The real problem I see with the setup in the OP is if the plan is to generate useful electricity while riding, it needs to be at very low speed. Otherwise the increased wind resistance is likely to offset the power generated by the panels. That's why my s...
by avandalen
Dec 30 2010 4:13pm
Forum: E-Bike Build Threads / Photos & Video
Topic: My solar bike
Replies: 56
Views: 9693

Re: My solar bike

vanilla ice wrote:Make it a shade, with the support coming up from behind the seat post. That would be nice on hot sunny days. How heavy are those panels?
Thanks, that is a good option! The goal is a panel weight of about 2 kg total, it is definitely not cheap...
by avandalen
Dec 30 2010 3:58pm
Forum: E-Bike Build Threads / Photos & Video
Topic: My solar bike
Replies: 56
Views: 9693

Re: My solar bike

GrayKard wrote:The panel placement looks a bit awkward to me. Hard to ride it on a crowded sidewalk. I think trailer mounting would be a more viable option but still wouldn't be sporty.

Gary
Yes, I can't ride it on a crowded sidewalk...
Gary, can you look at the added articles at my site?
by avandalen
Dec 30 2010 3:57pm
Forum: E-Bike Build Threads / Photos & Video
Topic: My solar bike
Replies: 56
Views: 9693

Re: My solar bike

Hi, Even if the manufacturer claim 21% efficiency you won't get more than 17% in the best case (with Mppt and at lunch time in the summer). I'm curious to know how much surface are you aiming ton mount on your bike? I have a 120W mono-crystalline panel (with "only" 16% efficiency) at home and it we...
by avandalen
Oct 11 2010 12:59pm
Forum: E-Bike Build Threads / Photos & Video
Topic: My solar bike
Replies: 56
Views: 9693

Re: My solar bike

Dear dodjob, In the mean time I have finished the solar panel article on http://www.avdweb.nl. The solar panels will produce between about 100 W and 140 W at cloudless summer days. This should be enough for only the assistance at hills. Dear GrayKard, The most people have the same opinion about the ...
by avandalen
Oct 02 2010 10:53am
Forum: E-Bike Build Threads / Photos & Video
Topic: My solar bike
Replies: 56
Views: 9693

My solar bike

The goal of this project is making a solarbike that at sunny summer days receives enough solar power to allow cycling longer distances and cycling hills with sufficient assistance. Instead of the common ebikes, which are heavy, de solarbike must be lightweight and sportive. It may not cost substanti...