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Old 07-08-2011, 08:32 AM   #83 (permalink)
bwilson4web
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Quote:
Originally Posted by dcb View Post
. . .
from seconds 335 to 355 you are indicating an increase in speed from maybe 43 mph to 49 mph. At the same time you are indicating the ICE wattage going from a peak of ~13.5kw down to ~10kw. The battery isn't doing anything terribly interesting either at that time, . . .
Correct as this is field data. I don't have the exact altitude data but the profile is consistent with driving north from a stoplight at:
  • latitude longitude :: altitude
  • 34.665634 -86.572073 :: 186m(*)
  • 34.674184 -86.574830 :: 180m
  • 34.678893 -86.576275 :: 180m
The 6m drop in altitude is enough to contribute the slight speed increase while the engine power is going lower.

The data shows:
  • 298-304 - traction battery supported launch from dead stopped
  • 304-318 - normal operation where MG1 is the generator and MG2 is the motor
  • 318-320 - transition from normal to energy recirculate mode
  • 320-end - MG2 is generating the power that flows to MG1 to provide counter torque for the ICE

Quote:
Originally Posted by dcb View Post
. . . conditioning efficiency of 70% prior to mechanical conversion? . . .
This reads like professor Raf Catthoor's efficiency number, 70%, which he states without showing how it was calculated or measured. Perhaps you can show how the 70% was calculated?

For efficiency, I prefer to use lab measured, ORNL/TM-2006/423, Appendix B, which gives a range of values from 55.5-92.7%. Given the fairly low power range, the efficiencies should be relatively high.

Bob Wilson

* - there are multiple stop lights along this route and any one of them could have been the starting point. It would be easier to re-run the test with a GPS track IF there were a serious question about the data.
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Last edited by bwilson4web; 07-08-2011 at 09:36 AM..
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