Energy-efficient brushless motor breakthrough might allow for better automation

Innovations in brushless motor design could in future significantly enhance the performance of lab equipment, offering quieter operation and improved energy efficiency for pumps and fans.

Researchers at Graz University of Technology (TU Graz) have developed a new generation of brushless electric motors that consume less energy and generate less noise. This breakthrough, part of the “CD Laboratory for Brushless Drives for Pump and Fan Applications” led by Annette Mütze, introduces improvements in motor design, control techniques, and manufacturing processes, delivering enhanced performance without increasing production costs.

Reducing Vibrations Through Design

A key innovation lies in the reduction of “cogging torque,” an effect caused by the uneven engagement of magnetic poles in the motor’s stator and rotor. This unevenness creates jerky movements, which result in noise and vibrations. To address this, Mütze’s team modified the claw poles of the motor, skewing and slotting them to smooth out the engagement process. This reduces vibrations by 70%, with no added manufacturing costs.

This innovation allows the motor to run more quietly and smoothly, addressing a critical source of noise in small electric drives. Such motors are commonly used in pumps and fans, where reducing vibrations extends the lifespan of components and improves overall reliability.

Improving Efficiency with Simplified Control

In addition to mechanical improvements, the research team optimised the control of the motor’s electrical current. Most motors use pulse width modulation (PWM) to regulate current, a process that requires frequent switching and leads to energy losses. Mütze’s team simplified this process, reducing the number of switching operations.

Instead of switching the current multiple times per cycle, the new motor design switches only once per cycle, greatly reducing switching losses. This results in significant energy savings, especially at lower power settings, where traditional motors are less efficient. Furthermore, the reduction in switching operations lowers the number of capacitors needed on the motor’s circuit boards, cutting costs and increasing the motor’s durability.

3D Printing for Lighter and Cheaper Motors

Another innovation is the use of 3D-printed ferrite cores in the motor’s printed circuit boards (PCBs). Ferrite materials are traditionally heavy and costly, but by using 3D printing technology, Mütze’s team was able to create lighter, more cost-effective components that still offer excellent magnetic performance.

These 3D-printed cores improve the motor’s magnetic flux, allowing it to function efficiently with less expensive ferrite magnets. This approach not only reduces the motor’s weight but also automates part of the production process, making these motors more scalable and affordable for wider applications.

Applications in Laboratory Equipment

These advancements in motor technology could significantly benefit a wide range of laboratory equipment. Peristaltic pumps, often used for precise fluid handling, will run more quietly due to the reduction in motor vibrations. For vacuum pumps, which are critical in various lab processes, smoother operation will reduce wear and tear, improving reliability and extending the life of these systems.

Air filtration units, commonly found in clean rooms and fume hoods, can also take advantage of these energy-efficient motors. These systems typically run continuously to maintain air quality, so the energy savings from the new motor designs will reduce operational costs. The quieter operation will be particularly useful in labs where multiple units run simultaneously, contributing to a more pleasant work environment.

Hopefully, this innovation will move from research product to production quickly and find applications in laboratory automation.