Bear with me, I have to get my 2 cents in on what makes a motor "brushless"
Actually AC motors, either single or polyphase, are not "brushless" motors at all, the industry term "brushless" refers to motors that are electronically "commutated" and function with the characteristics of a brushed motor (KV??? timing?????), the industry designation for these motors is "brushless DC motors"
The motors we use, while they may look a lot like a 3 phase ac motor, are an anomaly as motors go, they cannot be used without some form of controller, either a variable frequency drive or a brushless controller, they are basically unusable on fixed frequency ac (50/60Hz) as they lack the ability to self start under those conditions.
Our brushless controllers are not a dv/ac inverter, as they do not create ac independant of the motor, they provide commutation to the motor, which is a closed loop system, using feedback from the motor to time the switching/commutation (yes, dc brushed motors internally are ac motors, but we call them dc, since that's what we feed them)
Motors used with a BLDC contoller have their RPM determined by the voltage applied (in our case PWM), just as their brushed counterparts, hence the use of a KV rating.
AC motors (non-commutated) have their RPM determined by the line frequency, rather than voltage. That's why oour Dremel tools must use a series wound brushed motor to gives us 30KRPM
an ac induction motor on 60Hz has a max no-load RPM of about 3550 (assuming 2 pole) no way will it spin faster without increasing the frequency.