Electromagnetic motor having permanent magnet rotor and stator and method for designing the same
A vehicle comprises: one or more road wheels configured to cause the vehicle to move; a steering wheel configured to generate an input for controlling the one or more road wheels; a brake assembly configured to operate a vehicle brake associated with the one or more road wheels; and one or more motors operatively connected to one or more of the one or more road wheels, the steering wheel and the brake assembly, at least one of the motors comprising: a stator assembly; and a rotor assembly configured to be rotatable relative to the stator assembly, the rotor assembly having a plurality of poles, wherein each of one or more of the poles of the rotor assembly comprises one or more substantially I-shaped slots and one or more substantially flat-top-U-shaped slots. One or more magnets may be disposed in one or more of the I-shaped slot(s) and the flat-top-U-shaped slot(s).
1 . An electromagnetic motor comprising:
a stator assembly; and
a rotor assembly configured to be rotatable relative to the stator assembly, the rotor assembly having a plurality of poles, wherein each of one or more of the poles of the rotor assembly comprises one or more substantially I-shaped slots and one or more substantially flat-top-U-shaped slots,
wherein any magnet disposed in the one or more substantially I-shaped slots and the one or more substantially flat-top-U-shaped slots, which is located closer to an outer surface of the rotor assembly, have shorter widths and/or thicknesses than another magnet disposed in the one or more substantially I-shaped slots and the one or more substantially flat-top-U-shaped slots located farther from the outer surface of the rotor assembly,
at least one of the substantially flat-top-U-shaped slots has two arm slot portions and a flat top slot portion connecting between the two arm slot portions such that the flat top portion and the two arm slot portions are connected to form one single slot,
the electromagnetic motor further comprises second and third magnets disposed in the two arm slot portions of the at least one of the substantially flat-top-U-shaped slots, respectively, and
the second magnet and the third magnets disposed in the two arm slot portions of the at least one of the substantially flat-top-U-shaped slots, respectively, are different from each other.
2 . The electromagnetic motor according to claim 1 , wherein the two arm slot portions of the at least one of the substantially flat-top-U-shaped slots are angled with respect to the flat top slot portion of the at least one of the substantially flat-top-U-shaped slots.
3 . The electromagnetic motor according to claim 1 , wherein the one or more substantially I-shaped slots are disposed closer to an outer surface of the rotor assembly than the one or more substantially flat-top-U-shaped slots.
4 . The electromagnetic motor according to claim 1 , wherein any slot of the one or more substantially I-shaped slots and the one or more substantially flat-top-U-shaped slots, which is located closer to an outer surface of the rotor assembly, has shorter widths and/or thicknesses than another slot located farther from the outer surface of the rotor assembly.
5 . The electromagnetic motor according to claim 1 , further comprising a first magnet disposed in the flat top slot portion of the at least one of the substantially flat-top-U-shaped slots.
6 . The electromagnetic motor according to claim 5 , wherein non-magnetic material or air gap is formed in the two arm slot portions of the at least one of the substantially flat-top-U-shaped slots.
7 . The electromagnetic motor according to claim 5 , wherein one or more hooks are formed adjacent to an end portion of the first magnet between the flat top slot portion and one of the two arm slot portions of the at least one of the substantially flat-top-U-shaped slots to hold the first magnet.
8 . The electromagnetic motor according to claim 1 , wherein second and third magnets disposed in the two arm slot portions of the at least one of the substantially flat-top-U-shaped slots, respectively, are rare-earth magnets, and a first magnet disposed in the flat top slot portion of the at least one of the substantially flat-top-U-shaped slots is a non-rare-earth magnet.
9 . The electromagnetic motor according to claim 1 , wherein non-magnetic material or air gap is formed in the flat top slot portion of the at least one of the substantially flat-top-U-shaped slots.
10 . The electromagnetic motor according to claim 1 , further comprising:
a first magnet disposed in the flat top slot portion of the at least one of the substantially flat-top-U-shaped slots; and
second and third magnets disposed in the two arm slot portions of the at least one of the substantially flat-top-U-shaped slots, respectively.
11 . The electromagnetic motor according to claim 10 , wherein one or more hooks, and air gap or non-magnetic material are formed between the first magnet and the second or third magnet in the at least one of the substantially flat-top-U-shaped slots.
12 . The electromagnetic motor according to claim 1 , wherein:
one or more magnets are disposed within the one or more substantially I-shaped slots, and
one or more hooks are formed adjacent to an end portion of the one or more magnets disposed within the one or more substantially I-shaped slots.
13 . The electromagnetic motor according to claim 1 , wherein:
second and third magnets are disposed in the two arm slot portions of the at least one of the substantially flat-top-U-shaped slots, respectively, and
one or more hooks are formed adjacent to one end portions of the second and third magnets which are located closer to an outer surface of the rotor assembly than other end portions of the second and third magnets.
14 . The permanent magnet motor according to claim 1 , wherein a first magnet disposed in the flat top slot portion of the at least one of the substantially flat-top-U-shaped slots is larger than second and third magnets disposed in the two arm slot portions of the at least one of the substantially flat-top-U-shaped slots, respectively.
15 . A vehicle comprising:
one or more road wheels configured to cause the vehicle to move;
a steering wheel configured to generate an input for controlling the one or more road wheels;
a brake assembly configured to operate a vehicle brake associated with the one or more road wheels; and
one or more motors operatively connected to one or more of the one or more road wheels, the steering wheel and the brake assembly, at least one of the motors comprising:
a stator assembly; and
a rotor assembly configured to be rotatable relative to the stator assembly, the rotor assembly having a plurality of poles, wherein each of one or more of the poles of the rotor assembly comprises one or more substantially I-shaped slots and one or more substantially flat-top-U-shaped slots,
wherein any magnet disposed in the one or more substantially I-shaped slots and the one or more substantially flat-top-U-shaped slots, which is located closer to an outer surface of the rotor assembly, have shorter widths and/or thicknesses than another magnet disposed in the one or more substantially I-shaped slots and the one or more substantially flat-top-U-shaped slots located farther from the outer surface of the rotor assembly,
at least one of the substantially flat-top-U-shaped slots has two arm slot portions and a flat top slot portion connecting between the two arm slot portions such that the flat top portion and the two arm slot portions are connected to form one single slot,
the electromagnetic motor further comprises second and third magnets disposed in the two arm slot portions of the at least one of the substantially flat-top-U-shaped slots, respectively, and
the second magnet and the third magnets disposed in the two arm slot portions of the at least one of the substantially flat-top-U-shaped slots, respectively, are different from each other.