Creating a PM Induction Generator from Induction Motor

In summary, using a washing machine motor to power a wind turbine will require at least as many magnets as are on the rotor.
  • #1
AaronWeber
2
0
Hello this is my first post, please let me know if I'm breaking any rules, I'm still a bit hazy on them.

I am in the process of making a permanent magnet induction generator from and old washing machine induction motor. The motor is rated 1725 rmp, 115 volts 6.3 amps at 1/3 horsepower. It is a single phase motor. I intend to use it for a wind turbine so running the rotor 5% above rated rpm's is not an option. Instead I would like to drill out the rotor and put in cylindrical Neodymium magnets 3/8" diameter by 1" length. If i want to run the engine at low RPM (say 0 to 600 for a turbine) how many magnets would I need to use to achieve an output of 500 watts or more, if that is possible.

Thanks all.
 
Engineering news on Phys.org
  • #3
Well what an an interesting project. I've thought about it for years but never acted on the thought.

Having never done this i can only suggest you'll need as many as you can fit into the rotor.

Washing machine motors are usually multispeed so you'll want to give your rotor the same number of poles as on the winding you select. I'd use the lowest speed winding (the one with the most poles)

We had an old thread on re-purposing washing machine motors here
https://www.physicsforums.com/threa...g-machine-motor-to-power-a-grain-mill.833300/
that'll help you identify the windings

I found a paper on PM machines
https://pdfs.semanticscholar.org/75ba/b56b1709df4c72bf8a52dbae35dd2715c18a.pdf
and here's an image from it of a four pole rotor (page 42 of the 115 page PDF)
annotated with my thoughts about the biggest problem i foresee
245451


you'll need to provide a wide annulus around your cylindrical magnets, at least twice the air gap of the motor,
so that flux doesn't find a shortcut through iron back to the other end of your magnets.

Honestly i'd look into modifying an automobile alternator.
There are plenty of Youtubes on making GM alternators into PM machines,
but look around junkyards - the larger the diameter the better low speed performance you'll get. Old Chryslers from early 60's were quite wide as best i remember.

old jim
 
  • Like
  • Informative
Likes sophiecentaur and anorlunda
  • #4
I moved this thread from the spring cleaning workshop to EE forum so that everyone can see @jim hardy 's great reply.

Thanks Jim.
 
  • Like
Likes jim hardy

FAQ: Creating a PM Induction Generator from Induction Motor

1. What is a PM induction generator?

A PM (permanent magnet) induction generator is a type of electric generator that converts mechanical energy into electrical energy. It uses a combination of permanent magnets and induction coils to generate electricity.

2. How is a PM induction generator created from an induction motor?

To create a PM induction generator from an induction motor, the motor's rotor must be replaced with a permanent magnet rotor. This can be done by either replacing the entire rotor with a pre-built PM rotor or by adding permanent magnets to the existing rotor.

3. What are the benefits of using a PM induction generator?

One of the main benefits of using a PM induction generator is its high efficiency. Permanent magnets have a stronger magnetic field than electromagnets, which are typically used in traditional induction motors. This results in a more efficient conversion of mechanical energy to electrical energy.

4. Are there any limitations to using a PM induction generator?

One limitation of using a PM induction generator is that it requires a constant source of mechanical energy to maintain the magnetic field. This means that the generator may not work well in applications where the mechanical energy source is inconsistent or variable.

5. What are some common applications of PM induction generators?

PM induction generators are commonly used in renewable energy systems, such as wind turbines and hydroelectric generators. They are also used in some industrial and commercial applications, such as in electric vehicles and backup power systems.

Similar threads

Back
Top