I've nearly never adjusted the PWM and I don't think, that it will have a huge impact.
Timing is very important with HW ESCs.
I set it up to 25 degrees of timing, which is the minimum on motors with 24 or 28 poles.
Hi,
the Timing depends not only on the number of poles, it depends on the rotational speed of the electric field (shaft rpm times poles/2),
winding R and L (not known), and the motor load (proportional to current). Turning on the voltage on the winding,
it needs time to reach the max. current (U/R) depending on the Time Constant L/R. To compensate the timing responce of the
winding and the resulting magnet field in the winding, an advance timing must be used to reach the max. torque of the motor.
If the timing is set too high, the direction of the magnet filed in the winding could be in the opposite direction of the rotating magnet
field of the rotor. As a result the motor stutters, it is like a backfire ignition on an IC engine.
Using a low timing is normaly not critical, you will have less power. Seting the timing too high you can damage your motor due short
torque ripples in the opposite direction and too high currents. Also the Timing e. g. 15 deg (mid timing) can be different
on the various brands of ESC's, the Timing is not a normed value/unit.
Your motor can run very good with 18 deg with an ESC brand XX, with brand YY and 18 deg maybe not. It is sometime hard to find out
what is the best setup. Running a motor with various loads from CT to WOT, the auto timing setup of
premium ESC brands like YGE, Kontronik or Scorpion is perhaps the best choice.
PWM frequency:
The PWM frequency has a big impact on part load operation efficiency. Turning On/Off (PWM frequency) the supply voltage leads
to high ripple currents in the motor winding depending on L/R, higher PWM frequencies reduces the amount of current ripples and
thus you have a higher motor efficiency. Most ESC's have freewheeling to reduce the power loses of the FETs during PWM operation,
thus higher PWM frequencies than 8 kHz could improve the overal efficiency.
Best regards
Micha