Brushless permanent magnet motor with unequal-width slots and method of producing the same

A method of producing a brushless permanent magnet motor with unequal-width slots, comprising the steps of:

• (a) selecting a motor stator having a number of slots NS equal to a multiple of 6, and selecting an even number approximately equal to or slightly less than the number of slots NS of the motor stator as the number of poles Np of a rotor magnet;
• (b) designing the motor with the selected number of poles Np, number of slots NS and regular equal-width slot structure, and adopting a single-layer centralized winding;
• (c) analyzing and computing the EMF, current, inductance, efficiency and slot fill factor of the motor, and adjusting the motor structure, coil diameter and number of coil turns repeatedly, until the conditions of the design are satisfied;
• (d) examining and verifying a magnetic flux density of a stator tooth and a back iron to prevent the occurrence of a magnetic flux saturation, and completing a structural design of a regular equal-width slot motor, such that each slot area is equal to Sa1;
• (e) maintaining the width Ws of a slot opening unchanged, and equally increasing the width on both left and right sides of a tooth tip of a first type of teeth wound with a coil until the width Wt3 of the tooth tip is equal to the width Wp of a magnetic pole, such that the stator slot opening shifts towards a second type of teeth wound with the coil;
• (f) adjusting the width Wt1 of a first type of teeth wound with a coil, and equally increasing the width of both sides of the first type of teeth until the coil pitch is equal to the width Wp of a magnetic pole, and a motor angle is equal to 180°;
• (g) adjusting the width Wt2 of a second type of teeth without a wound coil, and equally decreasing the width on both sides of the second type of teeth until a slot area Sa2 is greater than the original slot area Sa1 of the regular equal-width slot motor;
• and
• (h) examining and verifying the magnetic flux density of the stator tooth and the back iron to prevent the occurrence of a magnetic flux saturation.