Magnet-free electric motors: Driving innovation beyond rare earths

Electric motors are everywhere—from the cars we drive to the appliances in our homes—but most rely on rare earth magnets that come with high costs and environmental challenges. A new wave of innovation is changing that story. Magnet-free electric motors are proving that smart engineering can deliver powerful performance without depending on scarce materials.

By removing rare earths from the equation, these designs promise cleaner supply chains, more sustainable production, and fresh opportunities for industries ranging from electric vehicles to renewable energy. It’s a shift that could redefine how we think about powering the future.

Why rare earths matter

Rare earth magnets, especially neodymium and dysprosium, have been the secret ingredient behind the compact, high-torque motors that power everything from electric vehicles to wind turbines. Their ability to deliver strong magnetic fields in small packages has made them indispensable in modern motor design.

But there is a catch: mining and processing rare earths is energy-intensive, environmentally challenging, and geographically concentrated in just a few regions of the world. This creates supply chain risks, price volatility, and sustainability concerns that ripple across industries.

By understanding why rare earths became so central to electric motors, we can better appreciate the significance of moving beyond them—and why magnet-free designs are more than just an engineering curiosity. They represent a strategic shift toward resilience, affordability, and cleaner technology.

How do you pull without a magnet

So how do you build a motor without magnets? The answer lies in clever engineering that takes advantage of the natural properties of materials and the geometry of the motor itself. Instead of relying on powerful magnets to create motion, magnet-free designs use principles like reluctance torque—where the rotor naturally aligns with the path of least magnetic resistance—or induction, where currents in the rotor generate the force needed to spin.

These approaches may sound technical, but the idea is simple: by rethinking the fundamentals, engineers can coax motors into delivering the same performance we expect, without the rare earth magnets. The result is a motor that can be lighter, more affordable, and easier to manufacture at scale. And because these designs lean on widely available materials, they sidestep the supply chain bottlenecks that have long plagued magnet-based motors.

Why it matters

Magnet-free motors are not just an engineering breakthrough; they are a practical step toward cleaner, more resilient technology. By removing rare earths, manufacturers can cut costs, ease supply chain pressures, and reduce environmental impact.

The benefits ripple across industries: in electric vehicles, they promise more affordable and sustainable mobility; in renewable energy, they support wind turbines and other systems without relying on scarce materials; and in industrial machinery, they offer reliable performance with simpler, more scalable production.

In short, magnet-free motors matter because they combine innovation with real-world impact, helping power a future that is smarter, greener, and less dependent on limited resources.

Figure 1 Today’s magnet-free electric motors deliver high efficiencies for heavy-duty and commercial vehicle applications. Source: Advanced Electric Machines

Working principles of magnet-free motors

For learners, makers, and anyone with a curious engineering mind, the real excitement lies in how magnet-free motors actually work. Instead of relying on rare earth magnets to generate motion, these designs tap into fundamental physics—using reluctance torque, induction, or clever rotor geometry to produce rotation.

Think of it as guiding the motor to “want” to align itself with paths of least resistance, or harnessing currents induced in the rotor to drive movement. The beauty is that these principles are elegant, scalable, and rooted in concepts every engineer encounters early in their studies. By revisiting the basics with fresh eyes, magnet-free motors show how fundamental science can be reimagined to solve modern challenges.

At their core, magnet-free motors rely on clever ways to generate motion without permanent magnets, using principles that every curious engineer can appreciate.

That is, reluctance motors exploit the tendency of a rotor to align with the path of least magnetic resistance, producing torque through geometry rather than magnets. Induction motors create rotation by inducing currents in the rotor with alternating fields, a design that is simple yet powerful. Synchronous reluctance motors combine aspects of both, offering efficiency and control that rival traditional designs.

Each approach shows how fundamental physics—magnetic fields, current flow, and mechanical alignment—can be harnessed in different ways to achieve the same goal: reliable rotation. For learners, makers, and innovators, these principles are a reminder that rethinking the basics can unlock new possibilities for sustainable engineering.

Figure 2 A synchronous reluctance motor demonstrates magnet‑free operation with smooth torque characteristics. Source: ABB

It’s important to note that not all reluctance motors are the same. A synchronous reluctance motor (SynRM) runs in step with the supply frequency, using flux barriers in the rotor to align with the path of least magnetic resistance, delivering smooth torque and efficiency. A switched reluctance motor (SRM), by contrast, relies on sequentially energizing stator phases to pull a simple steel rotor around; it’s rugged and powerful but tends to be noisier with more torque ripple.

Sitting between these designs is the permanent magnet assisted SynRM (PMA‑SynRM), which adds small magnets to stabilize the field and boost efficiency while still using far fewer rare earths than traditional permanent magnet motors. Together, these variations show the spectrum of approaches engineers use to balance performance, simplicity, and sustainability.

Unlocking SynRM performance with VFDs

While SynRMs deliver smooth torque and efficiency, they typically need a variable frequency drive (VFD) to start and stay synchronized with the stator’s rotating field. The VFD supplies control frequency and voltage, making these motors flexible but dependent on modern power electronics.

By contrast, older induction motors could start “across the line”—plugged directly into the grid—though at the cost of high inrush currents and less precise control. This reliance on VFDs underscores how magnet-free motor innovation is inseparable from advances in drive technology, reminding designers that motor and electronics progress go hand in hand.

As a worthy side note, VFD is the electronic brain that makes modern motors flexible. By adjusting the frequency and voltage, it lets a motor start gently, avoid the punishing inrush currents of direct grid connection, and run at variable speeds with precision. For SynRMs, the VFD is essential—it keeps the rotor locked in sync with the stator’s rotating field. Older induction motors could start “across the line” without such electronics, but that simplicity came at the cost of efficiency and control.

Figure 3 A compact VFD module suitable for driving 3-phase SynRM motors supports efficient control in both industrial and household applications. Source: Mean Well

From a design standpoint, the dependence on VFDs is both enabling and constraining. On the enabling side, drives unlock efficiency gains, smoother torque, and precise speed control that make SynRMs competitive with permanent-magnet machines.

On the constraining side, they add cost, require integration expertise, and shift part of the reliability burden from the motor to the electronics. For engineers, it means evaluating magnet-free motors is not just about rotor geometry; it’s about the total system, where sustainability benefits must be balanced against drive complexity and lifecycle economics.

Note that modern control strategies such as field-oriented control (FOC) and sensorless vector control extend the capabilities of these VFDs. FOC regulates stator currents to deliver precise torque and flux, while sensorless vector methods estimate rotor position without mechanical sensors, reducing cost and improving reliability. Together, they allow SynRMs—and other magnet-free designs—to match the responsiveness and efficiency of permanent-magnet machines.

Quick FOC take: Field‑oriented control does not have to be daunting. For makers eager to experiment, compact FOC shields/modules provide a straightforward, low‑power entry point. The Arduino SimpleFOC Shield is a practical example, lowering barriers and making hand-on exploration accessible.

Figure 4 SimpleFOC Shield empowers accessible FOC experimentation for Arduino users. Source: Author

Next, getting into design significance, the combination of magnet-free motor design, advanced VFDs, and intelligent control strategies has broad implications. Engineers gain access to motors that are lighter, more affordable, and easier to manufacture at scale, while sidestepping rare-earth supply chain constraints.

In the long run, magnet-free motors not only reduce dependence on scarce materials but also align with global sustainability goals, positioning them as a cornerstone of next-generation electrification across industries spanning from manufacturing to consumer appliances.

Closing thoughts

Magnet-free motors are steadily moving from concept to reality, driven by both maker ingenuity and industry ambition. With BMW and Mahle advancing externally excited synchronous motors to reduce rare-earth dependence, and Tesla having already demonstrated the scalability of induction motors, the message is clear: sustainable propulsion can deliver performance without compromise.

For makers and engineers alike, this is an invitation to experiment boldly and rethink motor design fundamentals, because the next leap in innovation may emerge as much from a personal workbench as from an automotive R&D lab.

T. K. Hareendran is a self-taught electronics enthusiast with a strong passion for innovative circuit design and hands-on technology. He develops both experimental and practical electronic projects, documenting and sharing his work to support fellow tinkerers and learners. Beyond the workbench, he dedicates time to technical writing and hardware evaluations to contribute meaningfully to the maker community.

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