Hummie vs Devin (Volts conversion to amps)

@devin, I’m getting bored with this.

Now you either don’t want to understand or you are just trolling.

Please stop for a while, re-read what has been written, think about it for a while and let it all settle. Then go for a ride. This is what I will do.

That theory is definitely not correct ! You were comparing average power values on motor and battery side. The battery and motor current limits are completely independent values that are set to ensure the safe use of each component! The heat loss in both component is not the total power, and even that not the same for the battery and the motor, since the efficiency of motor, ESC, and all other components is <1.

The current that you can safely pull from a 35C battery uphill is 35C! The motor is more complicated. It has a current limit too. But the generated heat is not proportional to the current, nor is it to the average battery power or motor output power since the efficiency of the motor changes drastically between situations!

I think the point that you haven’t really wrapped your mind around is that the battery current and the motor current are almost completely independent systems separated by the VESC. There can be a high motor current flowing purely in the system motor <-> VESC without any current from the battery already from the fact that there is inductance. On top of that when the motor rotates you do not have these PWM + LCR scenarios but 3 additional sources of an AC voltage leading to the 3-phase-current situation.

So far we only discussed how a coil connected to a PWM signal behaves. This does not yet give you any valuable information on how to set motor or battery current limits.

The battery current is completely situational. It can be anything between 0 and the motor current.

Hey Devin, Have you come to any new conclusions? Reading your posts brought me here and made me create this account. Im going to look in-depth tomorrow after some much needed sleep. Anyway I came across this vid: https://www.youtube.com/watch?v=wbmEUi2p-nA did you ever play with the PID controller terms? Could it be integral term of the controller that is causing the input signal to get dampened, or maybe the P term which is not high enough to create a fast enough response?

Unless you use the ackmaniac app, the ESC control the current not the power. Current gives you torque and them speed depending on mechanical resistance. The power is simply a consequence of all that and equal torque x angular sped.

So I don t understand why some people say that higher volts gives lower amps? It does not make sense

I feel uneasy even coming back to this thread, but the sentence [quote=“Jerome, post:318, topic:6910”] higher volts gives lower amps [/quote] essentially the point is that you need lower battery current with higher battery voltage to produce the same power.

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I miss Devin in a weird kinda way

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I fully get that but did you read my thread?

Skaye are not power controlled they arecurrent controlled. So why does raising the voltage decreases the current? Power is a consequence of torque * speed , and speed is a function of torque And the mechanical resistance seen