1738

Item 1738

DESIGN: Electrotor-SloMo - Motor - Axial Flux - Overview - 4-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

The Tesla car motor is 4-phase.

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 electromagnets will be stationary (stator). A set of permanent magnets will be located on each rotor. The alternate phasing of the electromagnets will synchronize the two rotors. As on alternative A, the relatively slow speed of the rotor blades is achieved because of the large motor diameter, however it does not take advantage of the 2:1 reduction in alternative A.
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. The stator windings will be skewed.

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.

Windings (4-phase): I do not know, at this point, if either of the 2 are valid.

Delta: What would this be called here, in 4-phase? BOX?

Switching Table:

Electrical Angle

Phase

Terminal

0˚

90˚

180˚

270˚

A

1

A

2

B

1

B

2

C

1

C

2

D

1

D

2

Insulated-gate bipolar transistor

Star, Wye, Y:

See US patents 3,831,072 and 4,484,115 and 5,043641. Have complete hard copy or 1st page of each in 'Control -Motor' binder.

See 1740.html for means of working out this sketch.

This information comes from 'Performance of Disc Brushless DC Motor Applied as Gearless Drive for Wheelchair' ~ Hardcopy is in Dick motor binder and it is on removable drive (perhaps as ' Torus - Type'

More Information:

OTHER: Electrical - Motor - Winding

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

General Arraignment:

Ref; [Source ~ AFPM, section 2.1.3]

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.

Flux:

Commutation Sequence for Counter Clockwise Rotation (top rotor):

Control word [ABCD]

Phase A

Phase B

Phase C

Phase D

+V_DBC

-V_DBC

+V_DBC

-V_DBC

+V_DBC

-V_DBC

+V_DBC

Must a flux barrier 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:

contra rotating prop brushless ~ RC Groups thread

Idea for 4-phase:

General Arraignment:

The winding of the coils looks ideal, but

A magnet arraignment will have to be found that works with this winding.

Perhaps Relevant Patents:

5,043,641 US ~ Circuit for and method of controlling 4-phase brushless DC motors ~ August 27, 1991 ~ Have hard copy.

20070247017 US ~ Axial-Flux, Permanent Magnet Electrical Machine ~ October 25, 2007

3,831,072 ~ DC MOTOR WITH HALL GENERATORS

4,484,115 ~ Brushless motor Look interesting. Axial flux and it mentions 4-phase Have hard copy.

"brushless AND motor AND (4-phase OR four-phase)" brings up 148 US Patents. Review them

"brushless AND motor AND (4-phase OR four-phase)" brings up 70 US Patent Applications. Review them

See; DESIGN: Electrotor-SloMo - Control - Power - ESC - Four-phase - Overview

And; DESIGN: Electrotor-SloMo - Motor - Overview - 4-phase for SloMoCo (and Bilateral?)

Initially displayed: June 3, 2009 ~ Last Revised: September 5, 2011

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.

		Electrical Angle
Phase	Terminal	0˚	90˚	180˚	270˚
A	1
A	2
B	1
B	2
C	1
C	2
D	1
D	2