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Electronics => Projects, Designs, and Technical Stuff => Topic started by: Swobethy on August 21, 2024, 12:05:02 am

Title: Looking for Linear Motor Assistance.
Post by: Swobethy on August 21, 2024, 12:05:02 am

Hi All,
I'm currently attempting to create a linear motor (Photo attached). I've run into a few problems and I'm looking for anyone with any experience or knowledge I could help.

I've created a section for the linear motor with 24 Gauge wire with 40 wire turns to create the electrical field and once using it with my variable power supply I'm only getting input from amps. I was just Wondering if anyone knew a way to make an open circuit to have the variable input from the volts. I'm working with a 30v 10amp variable power supply and looking to move a small sheet of 2mm aluminium at 100 watts.

Open to questions and any help will be much appreciated. Cheers

Title: Re: Looking for Linear Motor Assistance.
Post by: Doctorandus_P on August 21, 2024, 12:25:45 pm

Electric motors usually work with permanent magnets. This lets you make use of the magnetic field of the coils directly.

But I also saw the video below:
https://www.youtube.com/watch?v=ZquvkS3vLjg (https://www.youtube.com/watch?v=ZquvkS3vLjg)

This setup is remarkably similar to yours. In the Aluminum plate you can generate eddy currents, which create a magnetic field of their own, and this can indeed be used to move the plate, but the interactions is much weaker. You also need a constantly changing field in the coils, or else no eddy currents get generated, and the aluminum plate will just sit there.

I find the use of an frequency inverter to drive an electric motor a quite ingenious idea, But also, these frequency inverters are designed to drive motors, so it's a logical choice too. These inverters output a low (average) voltage for low frequencies, and they have quite a lot of parameters you can adjust to tune them to the actual motor used. I'd say go buy one. These things only cost around EUR100.

While experimenting, do keep some safety in mind. With a frequency inverter all the coils get connected to high mains voltages, and the edge of such an aluminum plate can easily damage the thin insulation coating of the wires. That video is not a safe setup.

Title: Re: Looking for Linear Motor Assistance.
Post by: Swobethy on August 22, 2024, 03:01:02 am

Thanks for the response,
The video you have linked is what I first saw and am attempting to recreate.
Would you know where to find a frequency inverter or have any recommendations? 

Thanks