Guru
Joined: 15/07/2006
Location: AustraliaPosts: 640
| Posted: 11:29am 02 Aug 2008 |
oztules, lots of fun.
Problem appears to be not enough torque at the RPM. But when the RPM is increased by decreasing pitch, then the motor can accept more current, which results in greater output power.
We tested some other props, all varied in diameter, but smaller diameter than the original test. The results were just as much dissapointing. There was slightly more gain in thrust with the smaller props taking more amps at higher rpm, but nothing to get excited about.
I have no problem (in the right gear/speed) getting 500 amps at 150v to the motor in the Hilux, but could not get that amount of amps with any of the props. Voltage was no problem - 150v
The batteries cannot be the limiting factor, volts or available current. These Powersonic AGM are capable of delivering some 2000? amps.
Motor, not enough grunt. It has a peak of 75kw. We could not get that much.
The next test was done some time later by Foxcon. I was not there. 6 cheapy lead acids were connected (72v) direct to the motor and the thrust was similar to what we had acheived through the speed controller.
Then 12 of these cheapy lead acids were connected (144v) direct to the motor. The thrust pulled the scales to the end of the slide (200kg of force), and nearly blew the fellow over that was standing at the back to read the scales. He tryed to push the scales back but it was hard up against the end, it was not going to budge. I wish I was there. That would have been so good to see.
So........ this proves that it is not the motor. Could it be the speed controller ?????
Trev @ drivebynature.com