For decades, electric motor designers have been trying to beat the heat. Recent advances in energy-efficient AC motor designs might just get us there.
To operate a mid-to-high frequencies without generating massive amounts of heat, more engineers are turning to soft magnetic composites. Exclusive to powder metallurgy (PM), these electrically insulating materials combine excellent magnetic performance with the net-shaping capabilities innate to PM.
Let's look at how you can build a super-efficient electric motor that outpaces your competitors' work.
Advances in Energy-Efficient AC Motors: Why Pay Attention?
If a motor is more efficient, it'll save electricity. Simple, right?
Now, is it more expensive in the short term to switch to a powder metal part made from SMC? Most likely. Soft magnetic composite powder often costs more than the competing steel laminate it’s replacing.
So, yes, maybe you’ll have to use a little more copper, which is indeed an expensive metal. Or maybe you’ll have to alter your design slightly, which tacks on a little more cost.
In the end, it won’t matter. Your customers can spend more up front to save later.
You can absolutely conserve 5%-20% on electricity with the right powder metal. The exact percentage will depend on what alternative you’re comparing SMC with.
The long-term electricity savings are something you can promote to your own customers and pass the savings on to them if you wish. Thanks to powder metallurgy's green technology, you can also promote your electric motor as being environmentally friendly.
(Related article: Induction vs. Permanent Magnet Motor Efficiency)
How Soft Magnetic Composites Improve the Electric Motor Drive
You’ve learned that electric motor manufacturers can save customers money with soft magnetic composites. You’re probably wondering how exactly it works.
We’ve all picked up an electric motor. You feel the heat that’s being generated. You know that heat is an inefficiency.
The large cooling fan assemblies for electric motors consume a lot of energy and space. There’s a need for new solutions for electric motors that improve performance while reducing the need for large cooling system designs.
The solution? If you take what’s being converted into heat and just convert that into electromechanical energy, your motor will run more efficiently. So, higher efficiencies will generate less heat, and more of that energy turns into mechanical energy -- where it should be.
An example of where this comes into play is the modern air conditioning system. They run all the time. If you want to install a high-efficiency motor to cut your cooling costs, it’s much easier to do with soft magnetic composite parts. Then you can match the cooling load to what the actual compressor or fan is doing.
(Related article: How Magnetic Composites Impact NVH in Electric Vehicle Design)
Big-Picture Electric Motor Design
This little-known long-term savings trick is reminiscent of another secret we’ve shared with you. In some cases you can create a single SMC component that can serve the same function as 100s of pieces of lamination assembly. So paying a little more up front for raw soft magnetic material will cost less in the long run.
The most efficient electric motor designs always have the big picture in mind. Check with us if you need more concrete information about how much your design can be consolidated by using powder metal.
More Related Resources
- COMPONENT SPOTLIGHT: Electrical Lamination + Powder Metal Part
- Driving the Future of Electric Motor Stators With PM
- Electric Motor Core Materials: Steel Laminate vs. SMCs
(Editor's note; This article was originally published in August 2018 and was recently updated.)