Sona Comstar Develops, Validates Rare Earth Free Motor Based on Ferrite

NEW DELHI – With China’s curbs on exporting heavy rare-earth magnets disrupting global electric vehicle supply chains, India’s auto component major Sona Comstar has developed and validated a ferrite-assisted synchronous reluctance motor, which is a rare-earth-free alternative, for electric vehicles including two-wheelers, three-wheelers and light commercial vehicles. This is aimed at reducing import reliance and ensuring production continuity.

Currently, EV manufacturing remains heavily dependent on rare-earth minerals, which are critical for several key components—most notably the electric motor that converts electrical energy into mechanical power. Most electric vehicles use permanent magnet motors built with rare-earth elements such as neodymium, for which China remains the dominant global supplier.

Permanent magnet synchronous motors (PMSMs) are estimated to account for over 70–80% of EV traction motor applications. These motors use neodymium-iron-boron (NdFeB) magnets that offer exceptional magnetic strength, allowing for compact designs, high torque density, and superior efficiency.

However, this dependence poses significant risks. The rare-earth supply chain is highly concentrated and vulnerable to geopolitical disruptions, with China controlling the majority of production and processing. In April this year, China suspended exports of certain rare-earth magnets essential for EV motors, triggering supply shortages. 

Since April, automakers and component manufacturers have been racing to secure alternative sources and accelerate the development of motors that use lightweight or ferrite magnets—technologies that eliminate or reduce the need for rare-earth materials.

“This [supplying heavy rare earth magnets] shortage has impacted the production of EV traction motors for us in the first quarter. In response, we shifted to alternative motor designs that do not rely on heavy rare earth magnets,” Sona Comstar Managing Director and group CEO Vivek Vikram Singh told investors.

“Now we manufacture motors using light rare earth magnets and in this quarter we have also successfully developed, tested and validated a rare earth free, ferrite assisted synchronous reluctance motor for electric three wheelers and light commercial vehicles.”

Recently, Ola Electric received government certification from Global Automotive Research Centre (GARC) in Tamil Nadu for its ferrite motor, while Simple Energy has announced the start of commercial production of heavy rare-earth-free motors. TVS Motors and startups like Chara Technologies are also developing rare-earth-free solutions for traction motors.

Ferrite magnet motors use cheaper, widely available iron-based magnets instead of rare-earth elements like neodymium or dysprosium. While rare-earth magnet motors deliver higher torque and efficiency in a compact design, ferrite-assisted motors offer a cost-effective and alternative to rare-earth magnet motors but with slightly lower magnetic strength.

Sona Comstar management noted that while motors using rare-earth magnets (like in a standard PMSM) offer high power and torque density, they suffer from performance degradation at high temperatures. By leveraging this strength, the company claims that it has optimized the design of its ferrite-assisted synchronous reluctance motor to offset the lower magnetic strength of ferrite materials and higher weight for the motor.

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