Search found 228 matches

by devin
09 May 2017, 13:21
Forum: General
Topic: How should the VESC "feel" on a board?
Replies: 71
Views: 7403

Re: How should the VESC "feel" on a board?

The 71 amps are continuous and not modulated for a fraction of time. The modulation is what turns the 22 battery amps into 71 motor amps. There is no way you can draw 1kw from the battery and produce less than 1kw of heat when the mechanical power is close to 0. But: -duty cycle means % on time. -i...
by devin
09 May 2017, 13:11
Forum: General
Topic: How should the VESC "feel" on a board?
Replies: 71
Views: 7403

Re: How should the VESC "feel" on a board?

But I think 70.71 amps for 30.73% of the time produces as much heat as 21.72 amps for 100% of the time.

I dont think 70.71 amps for 30.73% of the time produces as much heat as 70.71 amps for 100% of the time.
by devin
09 May 2017, 13:08
Forum: General
Topic: How should the VESC "feel" on a board?
Replies: 71
Views: 7403

Re: How should the VESC "feel" on a board?

My point is I respectfully dont agree with you that motor heating would be equivalent to 71 amps in the example. I believe it would be equivalent to 22 amps.

71 amps for 30.73% of the time produces as much heat as 22 amps for 100% of the time.
by devin
09 May 2017, 12:36
Forum: General
Topic: How should the VESC "feel" on a board?
Replies: 71
Views: 7403

Re: How should the VESC "feel" on a board?

With that motor and 100A you will generate 1000W losses regardless of the speed, period. The instant you start moving the total power will increase or the current will decrease if you want to maintain the 1kw electrical power. devin wrote: I am trying to achieve Full Throttle = 1000w electrical int...
by devin
09 May 2017, 11:35
Forum: General
Topic: How should the VESC "feel" on a board?
Replies: 71
Views: 7403

Re: How should the VESC "feel" on a board?

You kind of got the relations right, but the motor resistance in your calculation should be doubled from the measured value since it estimates the resistance to the virtual ground point . However, your reasoning around standstill does not make any sense. Yes, you calculate the electrical power put ...
by devin
09 May 2017, 09:12
Forum: General
Topic: How should the VESC "feel" on a board?
Replies: 71
Views: 7403

Re: How should the VESC "feel" on a board?

@duggyboard after pulling my hair out for months to attempt to fully understand the motor amps / battery amps / startup torque acceleration issue , i've finally gotten a really good understanding of the issue. most of the surprising stuff I've learned i've summed up at http://MotorAmps.com Here are ...
by devin
08 May 2017, 06:41
Forum: General
Topic: code to change the motor amp limit
Replies: 138
Views: 29021

Re: code to change the motor amp limit

in the case of the use of 200 motor amps, -the single hub motor had 0.0415ohm windings -battery was assumed ~35v nominal under load -desired available wattage electrical at all possible rpms was 1660 watts -settings used were 48/200/200 batt/motor/absolute max 48 batt amps x 35v pack volts = 1680w 2...
by devin
08 May 2017, 02:45
Forum: General
Topic: code to change the motor amp limit
Replies: 138
Views: 29021

Re: code to change the motor amp limit

this graph seems odd in that the last 3 "power pulses" have correlated shapes between the 2 red lines, but the first 3 "power pulses" lose the correlation and appear to be "capped" or flatlined at some arbitrary value.

Go to advanced search