On Mon, Sep 30, 2002 at 01:27:46PM -0700, Victor Tikhonov wrote: > This is interesting data! > > Question 1: - the cliff position where constant torque turns into > constant power (4,400 RPM in your case) depends on the voltage. > What was the battery voltage during test? Looking at theoretical > curves for 5133 motor, sounds like the voltage was lower than 280VDC > during the test. http://www.metricmind.com/line_art/plot_all.gif
I was not driving, so I could not watch the voltmeter. System voltage more than likely did not drop below 300VDC. Unfortunetly I forgot to disable the rev limiter in the inverter, so at 4500RPM (slightly less on the plot) the inverter software began backing torque off to avoid overspeeding the transmission. I have a rather conservative RPM max of 5000 RPM due to my fear of bending the motor shaft again. Also I do not have a realistic number for the max RPM of the transmission, like many American cars redline on the ICE engine was 5500RPM. If I run the truck again I will set higher limits and come up with a good way for the dyno to measure motor RPM. The test also does not feature any shifts, since my clutch was non-functional (need to bleed the new slave cylinder). Since the dyno is an acceleration model, where the vehicle is just accelerating a large mass I'm not certain shifting would provide any more interesting info. > Question 2: Why the curves end at 5,700 RPM? The test stopped when the tech hit the stop button doing 60mph in 2nd, since we could not shift. We stopped as soon as HP began leveling off. I am assuming much of this is due to the inverter software limiting RPM. > For fun, you can temporarily put some extra batteries in the bed to > make system voltage 380V and test it on dyno. It will outperform > stock ICE engine. Not sure... the ACRX might make a more interesting testbed, since I would trust your adapter and Honda transmission more than the Ranger's. As I said, this was a very unscientific test. Mark -- "The greatest dangers to liberty lurk in insidious encroachment by men of zeal, well-meaning but without understanding." -- Justice Louis O. Brandeis, Olmstead vs. United States
