Sunday, February 28, 2016

Estimates of acceleration rates in different gears at maximum power and at continuous rated power.

The first set of data is based on maximum power output.  The actual transmission is not rated to take the full torque of the motor.

Blue on the left is an input, red on the right is the output, orange in the middle requires some sort of logic to be applied.

3200lbbest current guess
288VNissan Leaf pack
394VNissan Leaf pack
300Nmfrom chart in previous post
(MUST limit to prevent transmission failure)
221ft-lbunit conversion
160Nmfrom chart
118ft-lbunit conversion
3000rpmfrom chart in previous post
6500rpmlimited to redline on dashboard
126hp
67hp
94kWunit conversion
50kWunit conversion
327A
128A



4.24

3.781st16.03
2.122nd8.99
1.363rd5.77
1.034th4.37
0.845th3.56
25.1inYokohama Avid Ascend 195/65 R15 BlueEarth
78.85in
804827Yokohama says 827 accounting or deformation
12.19inBack calculated from rev/mile Yokohama spec.





TorqueHPLimiting force


1st1st1st1st
motorfind power maxground speedground force lbground force lbactual
rev/min94 kWmphlblblbsec
000.03490-34900.0
500162.334902094034900.1
1000314.534901047034900.2
1500476.83490698034900.3
2000639.13490523534900.4
25007911.33490418834900.5
30009413.63490349034900.6
350011015.83490299129910.7
400012618.13490261826180.8
450014120.43490232723270.9
500015722.63490209420941.1
550017324.93490190419041.3
600018827.23490174517451.5
650020429.43490161116111.7

The graph below looks like we could have a lot of fun from 0-30mph if the transmission holds :)



The data has been run based on continuous ratings, not peak capability.


Weight3200lbbest current guess
Voltage min.288VNissan Leaf pack
Voltage max.394VNissan Leaf pack
Torque max. 30sec160Nmfrom chart (MUST limit to prevent transmission failure)
Torque max. 30sec118ft-lbunit conversion
Torque continuous max.160Nmfrom chart
Torque continuous max.118ft-lbunit conversion
Motor knee speed3000rpmfrom chart
Motor max. speed6500rpmfrom chart
HP max.67hp
HP continuous max.67hp
Power max.50kWunit conversion
Power continuous max.50kWunit conversion
Amps max.175A
Amps continuous max.128A




Diferential4.24

Gear ratio3.781st16.03
Gear ratio2.122nd8.99
Gear ratio1.363rd5.77
Gear ratio1.034th4.37
Gear ratio0.845th3.56
Tire diameter25.1inYokohama Avid Ascend 195/65 R15 BlueEarth
Tire circumference78.85in
Tire rev/mile804827Yokohama says 827 accounting or deformatio
Tire radius12.19inBack calculated from rev/mile Yokohama spec.





TorqueHPLimiting force

find power max1st1st1st1st
motor
ground speedground force lbground force lbactual
rev/min50mphlblblbsec
000.01861-18610.0
50082.318611116818610.2
1000174.51861558418610.4
1500256.81861372318610.5
2000349.11861279218610.7
25004211.31861223418610.9
30005013.61861186118611.1
35005915.81861159515951.3
40006718.11861139613961.5
45007520.41861124112411.8
50008422.61861111711172.1
55009224.91861101510152.4
600010127.218619319312.7
650010929.418618598593.1

Even at continuous level power ratings 0-30 in 1st can be fun. What I infer from this data is that it can be left in 3rd gear all the time, or it can be placed in 2nd but if limited to 6500 rpm it will not be highway speed capable in 2nd. 



Yet to figure out:
  • Is it better to run second gear and not limit to 6500 rpm?
  • Is it better to run second gear in the city and change to 3rd for highway?
  • Is 3rd better all around as churning in the transmission will be less?
  • How much more efficient is running in 2nd at a lower amp draw than 3rd with a heavier foot?

1 comment:

  1. Anyone know how to actually post the excel files so others can see the equations and use them?

    ReplyDelete