1739

Item 1739

DESIGN: Electrotor-SloMo - Motor - Axial Flux - Overview - 2-phase for SloMoCo (and Bilateral?)

The 3-phase page may be OK but the 2-phase and 4-phase pages must be must be phased etc properly.
Overview:

An axial flux electric motor with one central stator and contra-rotating armatures on each side.

Notes:

See this page in conjunction with DESIGN: Electrotor-SloMo - Control - ESC - Four-phase - Overview Eventually to be replaced by 2-phase page.

Common:

Electric motor located between the two counter rotating rotor hubs. The motor has a large diameter and is very flat; basically a linear induction motor lay out in a ring or like a large disk armature (like a computer's hard disk drive).

Alternative A:

The "armature" is a directly coupled to one rotor disk and the revolving "stator" is directly coupled to the other rotor. The relatively slow speed of the rotor blades is achieved because of the large motor diameter plus the 2:1 reduction of having both the armature and stator rotate. CONCERN; The rotor and the stator may want to rotate at different speeds.

Alternative B:

The coils will be stationary (stator). Permanent magnets will be located on each of the two rotor. The alternate phasing of the electromagnets will synchronize the two rotors. Consider using hand rotation of the motor at startup to assure the correct direction of rotation. As on alternative A, the relatively slow speed of the rotor blades is achieved because of the large motor diameter, but this alternative does not take advantage of the 2:1 reduction.
Could the means of assuring counter-rotation at startup be used for cyclic during flight?

Axial flux, Rotor - Stator - Rotor, Non-slotted, Four-phase

This picture is a general representation of the following material. The magnet pole count and the coil count may be different.

Poles = 4, [+, -, +, -]

Coils = 1 coil per pole and per phase = 16

Each offset below is 1/8th of a pole to pole angle. I.e on a 4-pole motor the offset will be 11.25º.

Should consider 6-pole or 8-pole because of large diameter and slower rotational speed.

Offset 000 is at the bottom up to offset 111 at the top.

Double-sided Counterrotating Machine with Internal Ring-shaped Core Stator:

General Arraignment:
Drawing below must be redone to 2-phase

Ref; [Source ~ AFPM, section 2.1.3]

Windings:
Drawing below must be redone to 2-phase

________________

More Information:

OTHER: Electrical - Motor - Winding

Flux:
Drawing below must be redone to 2-phase

The sector changes as the magnet crosses the static flux vector line. Note that the vector lines are 22.5º off of the primary and secondary coordinates. The azimuths where there is not a control word is the azimuth where the transition from one sector to another is being made.

Commutation Sequence for Counter Clockwise Rotation (top rotor):
Data in table must be redone for 2-phase


Control word [ABC]	Phase A	Phase B
0	+V_DBC	-V_DBC
1	-V_DBC	+V_DBC

Must a flux barrier must be located between the upper and the lower plane of coils? Magnetic Field Shielding

Use Halbach arrays and slotted stator on later rotors?

Common to Alternatives:

The electric drive should be relatively light. This is because of the uses modern magnetic material, plus the fact that the rotor of the helicopter will provide much of the structural strength for the electric motor. In addition, there is no need for a reduction unit.
It might serve as a rotor brake.

Outside Information:

Initially displayed: June 3, 2009 ~ Last Revised: June 17, 2009

The above utility invention is openly and publicly disclosed on the Internet to negate another entity from patenting it. ~ Reference patent law 35 U.S.C. 102 A person shall be entitled to a patent unless - (a) the invention was known ... by others in this country, ..., before the invention thereof by the applicant for patent.