|
Symetron™ AC
Induction Pancake Motor vs.
Permanent Magnet Motor
|
Comparative Advantages |
Legend |
|
+ |
Advantage |
|
- |
Disadvantage |
|
Feature |
|
Symetron AC Induction Pancake |
|
Permanent Magnet Motor |
|
Torque
|
+ |
High
torque density
|
+ |
High
torque density
|
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Materials
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+ |
Uses
economical materials—copper wire, iron & aluminum
|
- |
Requires more expensive permanent magnet material found mainly in
China
|
|
Material Supply Source |
+ |
No source and supply limitations |
- |
Over 90% of world’s supply of neodymium is currently controlled by
China and subject to geopolitical issues. |
|
Manufacturing Costs
|
+ |
Low
manufacturing costs. Similar to standard AC motor.
|
- |
Higher
manufacturing costs
|
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Scalability
|
+ |
Very
scalable economically from small to very large motor sizes
|
- |
Historically too difficult to manufacture in large motor sizes.
|
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Power
Range
|
+ |
Wider
Range of constant power.
|
- |
Narrow
range of constant power typical. Difficult to provide “field
weakening”
|
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Failure Modes
|
+ |
Benign
failure mode
|
- |
Catastrophic failure mode
|
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Form
Factor
|
+ |
Flat
“pancake” form good for hybrid, integrated & hub applications
|
+ |
Flat
“pancake” form good for hybrid, integrated & hub applications
|
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Environment
|
+ |
More
resistant to contamination & harsh environments vibration & shock
|
- |
Higher
risk of contamination. More vulnerable to vibration & shock.
|
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Magnetic Field
|
+ |
Magnetic field can be turned ON/OFF
|
- |
Magnetic field is always on.
|
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Performance
|
+ |
Very
smooth acceleration. Less torque ripple
|
- |
More
torque ripple.
|
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Excitation
|
+ |
Full
control of motor excitation
|
- |
Less
control of motor excitation.
|
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