Can 3 phase AC current be applied to a BLDC and vise versa?
They are not the same.

In BLDC machine, the stator winding is concentrated. Hence the stator waveform will be trapezoidal. Whereas in PMSM the stator winding is distributed winding. Hence the stator waveform is sinusoidal.



For PMSM a suitable control is space vector modulation, whereas for BLDC the six step pulse switchig is more apropiate.

The downside of using different control method is cogging output torque of the motor.