|
gentle throttle ramp-up added to software
New feature added! Gentle Ramp up of throttle. There's a problem if you accelerate too fast from 0 RPM. A motor has about 0.01 Ohms of internal resistance, or even as small as 0.001 Ohms for a really big one. Also, the inductance is very small, like 60 uH or so. The inductance resists a change in current, which is helpful in current limiting. However, 60 uH is TINY! A worst case senario can see a 4 amp increase in a millionth of a second! So, it's tough to limit the current when it's growing so fast. So, one thing you can do is restrict the rate of growth of the PWM duty. For example, if you ram the gas pedal to the ground almost instantly, the software will make you wait like 5 or 10 seconds or whatever until it reaches 100% PWM duty. It doesn't limit how fast you can slow down, though. It is tested and working.
That buys me some extra time to monitor the current increase and shut things down if the current gets to high.
I still have about 91% of the space on the chip available! ya! Maybe I'll add space invaders if there's not much else to do.
|