Hi Michael,
I forgot to mention that an existing light 3-wheeled vehicle is used, so there is no need to design or modify that - preferably the motor simply bolts to the existing transmission with an adapter plate. If a Forklift/pump motor is used the adapter plate is just mechanical mounting/aligning and to seal the transmission, if a golf cart or similar motor is used, there should be a pilot bearing in the adapter plate as well since I do not believe that the original transmission of the 3-wheeler has a bearing where the motor attaches, but I would need to find out. Controller is most likely going to be a "Cursit" of 48V 250-300A but since I am aware that hot temp causes throttle back of the controller, I might recommend to opt for a 450A controller so that even when hot there still is a healthy amount of juice available to manouvre in traffic. Batteries will be Lithium, most likely LiFePO4 with BMS. There are range requirements so I think it will be a rather large pack, possibly even upgrade the voltage to get the range if tests show it is not enough. discharge requirements are quite relaxed so I am not too worried about stress, but due to requirement for longevity, the BMS will need to keep the pack well within safe margins. Charging will be more taxing due to the desire of fast-charge. Concluding - I am mostly looking for recommendations / experience if a golf car style motor can be trusted to run say 10 years in daily use, probably about 200k mi before it needs a complete overhaul - brush replacement can be done at intermediate intervals. Or can only a pump/forklift motor be trusted to run this long without trouble? Thanks! Cor van de Water Chief Scientist Proxim Wireless Corporation http://www.proxim.com <http://www.proxim.com> Email: [email protected] Private: http://www.cvandewater.info <http://www.cvandewater.infom> Skype: cor_van_de_water Tel: +1 408 383 7626 ________________________________ From: Michael Ross [mailto:[email protected]] Sent: Friday, June 06, 2014 7:34 AM To: Cor van de Water; Electric Vehicle Discussion List Subject: Re: [EVDL] recommendation for light EV components You could go with ebike/RC components and save a lot of $. Kelly Controllers, ebike hub motors all around (if you aver automotive wheels for bicycling gear). You probably only need a couple HP per person. There is a big uptick in the power needed if you design for 40mph continuous v 25 or 30mph continuous and short 40mph peaks. The tricky part is taking off from a stop which is where a pedal assist is a savings. If the land is flat that is a plus. All the components are smaller, lighter, cheaper if you don't supersize. 48V packs, I got a 20AH pack off of Alibaba for $450 - including BMS, charger, and a bag. So far very good for a year. These are LFP laptop cell sized ones with welded straps for connections. Reliable. Slightly smaller than the size of a group 24 battery. On Fri, Jun 6, 2014 at 4:43 AM, Cor van de Water via EV <[email protected]> wrote: I am assisting someone to design a light 3-wheel EV that should be able to run city speeds, no more than 40 MPH is needed and the weight will probably be under 1000 lbs (plus occupants). Not very aerodynamic but that should not be a problem at these speeds. I have some idea of what components can be used - battery pack should be Lithium to allow a good range and the voltage can be selected to match the performance of the motor/controller. At a minimum (to maintain constant speed) I am estimating about 3kW of power is needed, for (leisure) acceleration and hill climbing I am estimating about 10kW peak power. Since price is an important design criterium, my inclination is to see if one of the kits to give Golfcarts higher performance would be sufficient - most likely that or a similar DC motor setup will be used for this design. This means probably a battery pack of between 48 and 72 Volts. If necessary field weakening to get the motor the higher performance needed for acceleration (like a kick-down) while normal operation on the nominal voltage will give the more steady-state performance at lower current. Any other recommendation for affordable yet durable motor and controller? It is expected that the vehicle must be capable to run 200k mi without frequent overhaul. Thanks for any advice, Cor van de Water Chief Scientist Proxim Wireless Corporation http://www.proxim.com <http://www.proxim.com> Email: [email protected] Private: http://www.cvandewater.info <http://www.cvandewater.infom> Skype: cor_van_de_water Tel: +1 408 383 7626 <tel:%2B1%20408%20383%207626> -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20140606/6396 4d70/attachment.htm> _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA) -- Put this question to yourself: should I use everyone else to attain happiness, or should I help others gain happiness? Dalai Lama Tell me what it is you plan to do With your one wild and precious life? Mary Oliver, "The summer day." To invent, you need a good imagination and a pile of junk. Thomas A. Edison <http://www.brainyquote.com/quotes/quotes/t/thomasaed125362.html> A public-opinion poll is no substitute for thought. Warren Buffet Michael E. Ross (919) 550-2430 Land (919) 576-0824 <https://www.google.com/voice/b/0?pli=1#phones> Google Phone (919) 631-1451 Cell (919) 513-0418 Desk [email protected] <mailto:[email protected]> -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20140606/14287136/attachment.htm> _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA)
