Some basic education is in order, and I'm not convinced that this sort of discussion is the way to do it, but...I am new to electric cars so this question might appear childish (Sorry for that). I hope a positive answer from the community.
Which type of motor is more recommended, dc brushless or induction? I would like a technical answer. and which one is more efficient and recommended?
Brushless motors are fundamentally AC, although that's the start of an argument about terminology. Perhaps you could clarify what you think a "DC brushless" motor means.
If you are asking about the difference between
- a synchronous 3-phase AC motor with permanent magnet (PM) rotor, and
- an asynchronous 3-phase AC motor with induction rotor
If by "DC brushless" you mean a motor which is driven with square-wave power on three input terminals (not 3-phase sinusoidal AC), then that will certainly be less efficient and less effective than a normal 3-phase AC motor. This probably doesn't matter, because unless you are building something small (light motorcycle, for instance), you're unlikely to find a motor of this type with adequate power.