A131

DESIGN: Electrotor-SloMo ~ Motor

Overview:

Notes:

Information on Closest to Helicopter Requirement So Far :

CSIRO:

YUNEEC INTERNATIONAL:

Geiger Engineering:

Kollomorgen :

Allied Motion - Emoteq: Currently this looks the best for full size craft.

Frameless brushless torque motors:

ETEL Inc.

Siemens:

Technologies M4:

Zytek:

UQM Technologies, Inc.

IDAM - INA Drives & Mechatronics

From bill111 at Eng Tips Forum

INA may have what your looking for all developed. http://www.ina-dam.de/en/sub.php?page=16 Their main is impossible, but the link above should get you there (will these huge companies ever get a clue as to what the engineers need).
Read the descriptions carefully. They do have inside out brushless motors, of a fairly high power level.

Radial Engine: Rotapower:

Preferences:

The Idea:

Notes:

 

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From Rotary Wing Thread ~ ELECTROTOR

Intention:

Electronic and electrical components can be given redundancy. However, in the Electrotor's initial design, the primary planetary reduction and the secondary bevel reduction cannot be given redundancy. Any mechanical failure would render the craft uncontrollable.

The Electrotor will no longer have gears! A large diameter disk motor will be located in each of the two rotor hubs. Their low rpm will direct drive the rotors. The motors will have 2 stators with windings. A common (motor) rotor, with permanent magnets, will be located between them.

Each of the four stators will be physically interconnected to the pitch of a blade. The hope is that one stator can be provided with more power then the other and this will cause it to rotationally advance slightly in respect to the other stator. The rotational advancement would be restrained by a pitch-torque elastomeric device. Can the motor and its flux operate properly if the two stators are rotationally out of allignment? If not then consider a separate rotor for each stator, or a separate stator-rotor-stator for both blades.

For redundancy, the windings can be grouped into small numbers and powered by separate ESC's.

The concept will be somewhat similar to this idea. Coaxial - Electric Motor Located between Rotors

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Questions:

    1. Will rotational offset between the two stators, to provide different pitches of the two blades in the same rotor, cause problems for the magnetic flux?

      2. Note:

    2. Assuming that the windings are in the stators, the individual (windings?) is there any reason why they cannot be divided into 2 or 3 groupings for double or triple redundancy?
    3. Would 2-phase AC, or single-phase AC, be more efficient than 3-phase AC, once the direction of rotation was established? Note that the rotor only turns in one direction. Perhaps redundancy within the windings will allow for starting in the correct direction and then once rotation has been establish the redundancy can come into play?
    4. UBC ~ Department of Electrical & Computer Engineering? I spoke to Dr. Juri Jatskevich today ~ September 25, 2009

Stuff:

Brushless DC motors were developed from conventional brushed DC motors with the availability of solid state power semiconductors. So, why do we discuss brushless DC motors in a chapter on AC motors? Brushless DC motors are similar to AC synchronous motors. The major difference is that synchronous motors develop a sinusoidal back EMF, as compared to a rectangular, or trapezoidal, back EMF for brushless DC motors. Both have stator created rotating magnetic fields producing torque in a magnetic rotor.

Synchronous motors are usually large multi-kilowatt size, often with electromagnet rotors. True synchronous motors are considered to be single speed, a submultiple of the powerline frequency. Brushless DC motors tend to be small-- a few watts to tens of watts, with permanent magnet rotors. The speed of a brushless DC motor is not fixed unless driven by a phased locked loop slaved to a reference frequency

Single speed would sound to be ideal; since it comes with PWM?? I've got to understand how a motor can run slower than the power cycle with out 'skipping' something.

Random Notes:

Motor:

Patents:

Picture: Double-stator-single-rotor This is not the current choice.

The following is specific to Motor (for coaxial)

Overview:

Motor: Notes to be moved to lower pages:

Gimbal:

Lead page; SynchroLite ~ Rotor - Hub - 3-blade - Constant Velocity Joint w/ Hub Spring

Gimbal taken from DESIGN: SynchroLite ~ Rotor - Hub - 3-blade - CVJ & HS - Layout

Part of the above, which must be enlarged Bill of Material 1378

Scaling up by 2 means that all three coordinate dimensions must be increased by 1.26

However additional loads, such as the motor etc., will put additional forces on the components.

Therefore increasing all three coordinates by 1.33 will result in a scaling up of 2.35; instead of 2.

The various components must then be selected by next largest stock size.

Alternative Means of Power:

OTHER: Helicopter - Inside - Coaxial - Ultralight w/ Mid Engines

OTHER: Miscellaneous - Thoughtless Idea - Engine for Coaxial Rotor

Coefficient of Thermal Expansion:

Description

SmCo 1-5 Alloys

SmCo 2-17 Alloys

NdFeB

 

Perpendicular to orientation

13 x 10-6/°C

11 x 10-6/°C

-4.8 x 10-6/°C

 

Parallel to orientation

6 x 10-6/°C

8 x 10-6/°C

3.4 x 10-6/°C

 

 

Aluminum

Carbon Tow

Copper

Steel

Nylon

(10-6 m/m K)

22.2

negative

16.6

13.0

72

(10-6 in/in oF)

12.3

negative

9.3

7.3

40

Additional Information:

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Last Revised: January 15, 2010