From “Choke Point” To “Made in China”: How SDM Forges Domestic Strength in Magnetic Levitation Motor Rotors

I. What Is a Magnetic Levitation Motor Rotor?

When people hear “magnetic levitation,” many immediately think of the maglev train that “flies” along the track at Shanghai Pudong Airport. But few know that the same magnetic levitation technology has long since moved from the rails into bearings.

A magnetic levitation motor rotor is, simply put, a rotating component that “floats” in the air by means of magnetic force. The core principle is not complicated: magnetic bearings use electromagnets that generate magnetic force when energised, lifting the rotor completely clear so that there is no mechanical contact between the rotor and the stator. Position sensors constantly monitor any deviation in the rotor’s position, and a controller adjusts the electromagnetic force in real time to keep the rotor stably suspended at the intended position.

To use an analogy: a conventional bearing is like a wheel rolling on rough ground – lots of friction, lots of wear. A magnetic bearing is like a wheel that spins while hovering in the air – no contact, no friction.

This is precisely why magnetic levitation motor rotors offer outstanding advantages: low mechanical wear, low energy consumption, low noise, long service life, no need for lubrication, and no oil contamination. Rotor speeds can exceed 100,000 rpm, power ranges are broad, and control accuracy can reach the micron level. These characteristics make them particularly suitable for high-speed, vacuum, and ultra clean environments.

II. Why Do We Need to Replace Imports?

Although magnetic levitation technology is excellent, for a long time this key technology has been monopolised by a handful of foreign companies. Core technologies such as magnetic bearings, high-speed permanent magnet synchronous motors, and control algorithms have long been controlled by overseas players. Domestic users not only face exorbitant procurement costs – a single imported unit can easily exceed one million yuan – but also remain completely dependent on foreign suppliers for spare parts and after-sales service.

This “choke point” predicament is especially acute in several fields. In the semiconductor industry, high-end magnetic levitation equipment has long been imported, becoming a major bottleneck for precision manufacturing. In the field of high-power magnetic levitation equipment, domestic high-power products have long been absent. More importantly, this is not merely a cost issue; it is a matter of industrial security. “Keeping the vital lifeline in our own hands” has become a common aspiration of the domestic magnetic levitation industry.

III. SDM: A Magnetic Materials Company’s Journey to Domestic Breakthrough

In this wave of import substitution, SDM MAGNETICS CO., LTD. (SDM) is a significant player.

SDM’s product portfolio covers micro-motor stators and rotors, magnetic levitation motors, magnetic encoder sensors, resolvers, magnetic components and systems. Among these, magnetic levitation motors and their core component – the magnetic levitation motor rotor – are a key focus of the company’s strategic development.

These technical accumulations have been translated into tangible manufacturing capability. SDM has obtained multiple authoritative certifications including IATF 16949, ISO 9001, Carbon Footprint, and BSCI, and its products comply with RoHS, REACH and SGS testing requirements. Highly automated production lines and an advanced R&D laboratory provide a solid guarantee for the stable mass production of precision products such as magnetic levitation motor rotors.

IV. What Do Domestic Magnetic Levitation Motor Rotors Deliver?

The substitution of domestically produced magnetic levitation motor rotors for imports brings not only “availability” but also “excellence.”

First, huge energy savings. Magnetic levitation technology allows the rotor to run without any contact, greatly improving transmission efficiency. Compared with traditional motors, it can save 30-50% of energy, reduce operating noise to as low as 80 dB, and offer a design life of over 20 years. The rotor requires no lubricating oil and no frequent bearing replacements, giving the equipment a lifespan of several decades.

Second, total life-cycle cost advantages. Although the initial investment may be higher than that of conventional solutions, the maintenance-free and highly reliable nature means that the overall life-cycle cost is significantly lower. Magnetic levitation motors are also environmentally friendly, oil-free, and can reduce volume and weight by 80-90%.

Third, supply-chain security. From the rare-earth permanent-magnet materials needed for magnetic levitation motor rotors to complete magnetic levitation motor solutions, domestic companies like SDM are achieving full-chain independence – from materials to finished products. What was once a “choke point” technology is now becoming a new calling card of “Intelligent Manufacturing in China.”

V. Outlook: From Substitution to Leadership

In 2025, the size of China’s magnetic levitation motor market has reached 442 million yuan, up 12.06% year-on-year. The global magnetic bearing market is expanding at a compound annual growth rate of over 15%. With continuous improvements in permanent-magnet material properties and control algorithms, the stability and reliability of magnetic levitation motor rotors are steadily increasing.

From semiconductor manufacturing to data-centre cooling, from wastewater treatment to biopharmaceuticals, from central air-conditioning to precision instruments, magnetic levitation motor rotors are quietly entering more and more fields. They are no longer just a component; they have become a “core weapon” for the transformation and upgrading of “Intelligent Manufacturing in China.”

Once, we could only buy others’ technology at high prices; today, we use our own technology to make better products. SDM and other domestic magnetic levitation pioneers are writing a vivid chapter in the journey from “choke point” to “fist of strength.”