Hello Marco, My first EV had a GE-11 inch motor rated at 32 hp at 6000 rpm. The battery pack was a 180 volt 300 ah lead battery which made the EV weigh 7850 lbs. It had a 3 speed manual transmission with a 1st gear ratio of 3.5:1, 2nd gear ratio at 2.5:1 and 3rd gear at 1.0:1.
The differential gear is at 5.57:1. The overall ratio in 1st gear x 5.57 is about 19:1, the 2nd gear is about 13:1, and the 3rd gear becomes 5.57:1. Maximum range at 50% SOC is about 39 miles at level driving. Here in Montana, my driving is either up grade up to 42 degree which the motor ampere could get up to 600 amps and battery 200 battery ampere at speeds up to 70 mph for about 5 miles going to work every day. These batteries lasted me about 10 years. A master mechanic that works with me, said you should try a hydro drive which is use on large land movers. They are like four torque converters gang together. Each torque converter has a ratio of 1.8:1 at start up and ends at 1.0:1 at stall. Something like a variable gear transmission. Four torque converters would equal to 1.8 x 1.8 x 1.8 x 1.8 times the differential ratio of 5.57 would equal to about 58:1 overall ratio!! Most of my driving is now at a lower speed of 25 to 10 mph city driving, therefore the motor and torque converter lock up should match the motor sweet spot which is the point where the maximum hp and maximum torque of the motor becomes. The GE-11 or WarP-11 sweet spot is at about 1800 rpm, the WarP-9 sweet spot is at about 3300 rpm. I try the WarP-9, but the start out ampere at about 1 to 25 mph was too high going up to 600 motor amperes even at a 19:1 overall ratio. The maximum continuous motor ampere should be limited to 200 motor amperes which is about 75 battery amperes. So I than tried the hydro drive, but with only one torque converter which is a 12 inch diameter which was the largest one that I could get into a transmission bell housing. This torque converter was design for very large vehicles like a bus. It has a very low rpm lock up and full lock up at 1700 rpm which about matches the sweet spot of the motor. I had TCI.com built up a GM TH-400 automatic transmission to a manual mode which uses a manual valve body, with eliminates the governor and any exterior control systems such as a computer controller and/or vacuum control modulator. Now my start out motor ampere going up a 30 degree hill at 25 mph is now held to 200 motor ampere at 75 battery ampere on dry pavement. Push through a foot of snow, I still can hold 200 motor ampere at 75 battery ampere at 15 mph. I have increase my range of my EV by about 25% using 250 AH batteries in a EV that now weighs about 6800 lbs. The shifting technique I use is when the motor becomes 1800 rpm and the motor ampere is at 200 amperes, shift into the next gear. The motor ampere is still at 200 amperes while the motor rpm drops a bit. Bring up the motor rpm back up to 1800 rpm and shift again and etc for each gear change. Roland ----- Original Message ----- From: Ing. Marco Gaxiola<mailto:[email protected]> To: 'Electric Vehicle Discussion List'<mailto:[email protected]> Sent: Thursday, January 16, 2014 8:11 AM Subject: [EVDL] Electric Tractor for a Farm... I have a customer request who wants me to convert a Tractor into all electric for a special purpose; All the process involved in the tractor daily's job, it's performed by a factory 95CV motor (93.7HP) on the tractor. And would like to know if someone has made such a similar conversion that could give me some advice and recommendations that if this can be done, I'm sure can be done, better said; that is this could result in a positive, costs competitive Vs actual way. Is this not a crazy thing?. I've read in past threads about a small mower/lawn tractor, but this proposal may be in some way bigger and will involve a big battery pack, and system at all. Actually I haven't thought about the batteries, range and chargers, I've focused only in the motor issue. Thinking of the size of the electric motor, should I consider to put one that keeps HP close to the original max 93.7HP offered from factory? (I know that most of the times on conventional ICE vehicles, that Max HP rate is rarely used. Also; this tractor motor its small, but the continuous work at high RPMs and high gearboxes reduction it has is what makes it very strong, Slow but strong). So, based on my experience and looking at some different EV conversions I think this proposal could be a non impossible and a great challenge. And, if technical issues and financial availability is achieved could result in benefit of this customer. My idea it's based on replacing the 95CV ICE motor for one or two Warp9 or ImPulse9 motor (or paralleled DC motors) which will bring some about 60HP at continuous RPM, and if math on gearbox relation from original ICE motor (HPs Vs RPM) doesn't match perfectly, I could take advantage or the III speed reducing extra gear the tractor has. (those vehicles usually has 4 conventional gears, plus 3 more for extra torque/force, they only use I and II gear for actual purpose for that extra) https://lh3.googleusercontent.com/-tO04DDqsn-8/Usw-FY-cA1I/AAAAAAAAIuo/P1CmL<https://lh3.googleusercontent.com/-tO04DDqsn-8/Usw-FY-cA1I/AAAAAAAAIuo/P1CmL> eUgLA4/w623-h564-no/Electric+Tractor.jpg Case iii tractor jx95: <http://www.caseih.com/es_es/Productos/Tractores/Documents/JX/9C0003EOO.pdf<http://www.caseih.com/es_es/Productos/Tractores/Documents/JX/9C0003EOO.pdf>> http://www.caseih.com/es_es/Productos/Tractores/Documents/JX/9C0003EOO.pdf<http://www.caseih.com/es_es/Productos/Tractores/Documents/JX/9C0003EOO.pdf> (Specs on page 11) Various pictures: <https://plus.google.com/photos/109469848356360136281/albums/595599239036604<https://plus.google.com/photos/109469848356360136281/albums/595599239036604> 5665> https://plus.google.com/photos/109469848356360136281/albums/5955992390366045<https://plus.google.com/photos/109469848356360136281/albums/5955992390366045> 665 Ing. Marco Gaxiola Futuro Inteligente - CEO/Director <https://www.facebook.com/EvMarch<https://www.facebook.com/EvMarch>> https://www.facebook.com/EvMarch<https://www.facebook.com/EvMarch> --- Este mensaje no contiene virus ni malware porque la protección de avast! Antivirus está activa. http://www.avast.com<http://www.avast.com/> -------------- next part -------------- An HTML attachment was scrubbed... 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