Minute briefing in 12 screens.

1. Benefits of Motors with Copper Rotors
Minute Lectures
• Copper has a higher conductivity than
aluminum (57 MS/m compared to 37
MS/m)
 An induction motor with copper rotor can
be more efficient, or for the same
efficiency, lighter and smaller
• For a long time, the high melting point
of die-casting copper was a major
barrier
Copper or Aluminum for Motor Rotor?

2. Benefits of Motors with Copper Rotors
Minute Lectures
• Over the past years, several breakthroughs in copper
die-casting technology have been achieved
 Leading to industrial production of copper motor rotors
Die casting copper

3. Benefits of Motors with Copper Rotors
Minute Lectures
• Regular production of copper rotor motors in the
range 100W – 100kW
• 250,000 units are in use
• Average efficiency improvement compared to
aluminum rotor motors is around 3%
• Global electricity savings potential is 108 TWh/year
 Equivalent to 60-70 million tonne CO2 emissions
Copper rotor today

4. Benefits of Motors with Copper Rotors
Minute Lectures
• Two ways to use the higher
conductivity of copper:
 Same design
The motor has a higher efficiency,
compensating for its higher
purchasing price
 Same efficiency
The motor can be made lighter and
smaller, and therefore cheaper
Main benefits of motors with copper rotor

5. Benefits of Motors with Copper Rotors
Minute Lectures
Other benefits of copper rotors
1. A lower temperature rise in operation
 Other parts can heat up more, or less
cooling facilities are required
 A more compact machine,
fitting better into a system
2. A flatter efficiency curve
 Smaller efficiency drop when
deviating from the nominal load

6. Benefits of Motors with Copper Rotors
Minute Lectures
Other benefits of copper rotors
3. Torque-speed characteristic
reaches maximum torque at
higher speed
 Useful for combining high speed
with high torque (e.g. centrifugal
pumps)

7. Benefits of Motors with Copper Rotors
Minute Lectures
Other benefits of copper rotors
4. Improved steel properties
 Due to the higher melting point of copper,
the temperature of the surrounding steel
becomes higher during die-casting, which
can lead to a more energy-efficient
magnetic steel with proper steel
specifications

8. Benefits of Motors with Copper Rotors
Minute Lectures
Environmental performance
Two possibilities:
 Constant efficiency
= reduced material consumption
 Improved efficiency
= reduced energy losses
Recycling:
 A copper rotor is a composite material
= difficult to recycle, but techniques exist
to separate copper

9. Benefits of Motors with Copper Rotors
Minute Lectures
Operation issues
A copper rotor motor has:
 Lower starting torque
→ can be addressed by a special
design of the rotor slot shape
 Higher start-up current
→ requires use of a soft starter
 A higher rotor inertia

10. Benefits of Motors with Copper Rotors
Minute Lectures
Examples of applications
• Agricultural pumps (efficiency, torque)
• Water circulation pumps (efficiency, torque)
• Oil well pumps (efficiency, torque)
• Airport baggage handling (low volume)
• Rolling curtains (low volume, high speed)
• Aeronautic applications (low volume, high speed)
• Refrigeration compressors (high efficiency)
• Ceiling conveyor belt (low weight)

11. Benefits of Motors with Copper Rotors
Minute Lectures
Round-up
• Industrial production of induction
motors with die-cast copper rotor is
available today
• Main advantage: better conductivity of
copper, leading to improved efficiency,
or with the same efficiency, to lower
volume, weight and variable cost
• Improved steel in combination with
die-cast copper rotors enables Eff1
performance, or better, resulting in
reduced environmental impact

12. Benefits of Motors with Copper Rotors
Minute Lectures
Further information
• Website
www.copper-motor-rotor.org
• Production of copper rotors
www.favi.com
• Motors with Copper Rotors Can Cost
Less to Produce
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