Isnt Negative gate drive almost mandatory for IGBTs in BLDC inverter drives?
It's certainly an easy (generally) and effective option, especially for IGBTs and definitely recommended by manufacturers for modules.
Some other options:
1. Faster/stronger turn-off (using extra turn off diode and resistor). This helps the gate driver hold the voltage low. If you just lower the single resistor you will get also get a faster turn-on dv/dt negating some of the benefit of stronger turn-off.
2. Negative voltage rail. This gives more headroom for the miller spike before threshold. Many SiC FETs don't like negative rail drives, it significantly reduces their lifetime [1].
3. Miller clamp. Provides a shorting transistor very close to the gate-source without resistance that only turns-on once the switch is actually off.
4. Additional gate capacitance. The miller spike magnitude is determined by the ratio of miller capacitance and gate capacitance. If you increase gate capacitance you lower the spike. But you will need to drive more gate current for the same turn-on/off times.
Other Considerations:
1. Gate drive loop inductance. More inductance means the gate driver itself will have less bandwidth to hold off a high speed spike.
2. Boot strap high side supply doesn't easily create a negative rail.
3. There are many many app notes on this topic!
Thus a negative rail is not always mandatory (and SiC manufacturers even warn against). But if you already have isolated gate drive supplies it's very easy to add.
[1] Infineon AN2018-09