A motor constructed with wye winding is bound to be more efficient than the one in the delta configuration. In delta winding resistive losses are great and due to the overall configuration of the winding the parasitic electric loses are also on the higher side. There is no such thing in case of wye configuration.
How is a brushless or BLDC motor different from a normal motor?
A note: We are considering DC motors here.
Brushed motors are mechanical motors whereas brushless motors are solid-state electronics motor.
The commutator is the rotary switch which reverses the direction of the electric field inside a motor. This switch is widely used in brushed motors however it is not present in the brushless motors. This is a big difference in the construction of both the motors.
Commutator had many distinct disadvantages. The friction caused here created waste of energy hence decreasing the overall efficiency of the motor. The brush material was of a soft nature hence would get worn out easily. The resistance caused would also result in the drop in voltage. All these problems are not present in the brushless motor.
Other points of difference: