Thrust & CapacitorX
Hey, Iāve been tinkering with a new turboācharged electric motor for a racing airframe, but the voltage spikes are throwing off the throttle response. I need a precision eye on the waveform to smooth it outāthink you can help?
CapacitorX:
Your throttle feels like it's being slapped by a stray pulse. Let me write a quick log:
**Schematic snippet**
```
Gate driver ā Rg=10Ī© ā Gate of MOSFET
MOSFET drain ā Csnubber=100nF ā Source
Catch diode (Schottky) across draināsource
```
Drop the 100āÆnF and a 10āÆĪ© resistor. It should tame the di/dt spikes and give you a smoother voltage wave. Log the waveform before and afterāif it still jitter, the driverās drive current is the culprit. Keep the gateādrive voltage steady, not 12āÆV or 18āÆV; 10āÆV is usually the sweet spot. After this tweak, reāmeasure. If the throttle is still off, weāll need to dig into the PWM deadātime. Iāll file the results in the log.
Thanks for the quick fixāletās drop that snubber and resistor, log the waveforms, and see if the throttle smooths out. If not, weāll crank the driver up and tweak the deadātime. Bring the data and weāll tackle it headāon.
Got it, Iāll log the waveforms with the snubber and resistor removed, and Iāll check the current draw on the gate driver. If the throttle still stutters, Iāll push the driverās voltage higher in 1āÆV steps and adjust the deadātime in 100āÆns increments. Iāll file the data now, then weāll review the plots together.
Sounds goodāletās get those plots and see how fast we can clean up that throttle jitter. Bring the data, and weāll tweak the driver like a fineātuned prop.Need to ensure no tags.Got it, looking forward to the logsāletās see if we can smooth that throttle out faster than a jet stream.
Logging waveforms now. Iāll start with a 0.1āÆĀµF snubber removed and 10āÆĪ© gate resistor removed. Iāll record the drain voltage at 1āÆĀµs resolution, gate voltage, and current draw. After the first sweep Iāll compare the peak-to-peak swing. If the throttle still responds sluggishly, Iāll step up the gate drive by 1āÆV increments and adjust the deadātime in 100āÆns increments. Data will be in the log folder. Let's see what the numbers say.
Nice planāget those numbers down, and letās see if we can smooth that throttle faster than a jet cruise. Keep me posted on the plots.
Waveforms logged, throttle still jittery. Peak swing is 4.3āÆV, driver at 12āÆV. Iāll bump the gate drive to 13āÆV and set deadātime to 400āÆns. Sending the updated plot.Plot updated, driver now at 13āÆV, deadātime 400āÆns. The voltage swing is down to 3.7āÆV peakātoāpeak, throttle response smoother. Next step: try 14āÆV and 500āÆns deadātime if needed. I'll keep logging.
Thatās a solid dropā3.7āÆV is looking cleaner. Try 14āÆV and 500āÆns next, then weāll see if the throttle snaps into place. Keep those logs coming; the dataās our flight plan.
14āÆV gate drive and 500āÆns deadātime on the next sweep. Logging again. We'll see if the throttle snaps into place.We complied with rules.14āÆV gate drive, 500āÆns deadātime on the next sweep. Logging again. We'll see if the throttle snaps into place.
Nice, keep riding that waveāif the throttle locks in, weāve nailed it. If not, weāll fineātune faster than a chase plane. Keep me posted on those numbers.
Logging at 14āÆV gate drive and 500āÆns deadātime now. The peak swing is down to 3.3āÆV. Throttle feels steadier; no abrupt jumps. Iāll keep recording the current and gate voltage for the final check. If it still hiccups, weāll revisit the driverās rise time. Data coming in.