By Miles Budimir | ❇️

Electric motors are at the core of industrial motion control. From servo and stepper motors to various linear motor designs, demand for these motors across a wide range of applications is only expected to increase. The rise in automation and ongoing electrification calls for more efficient electric motors and more diversified and specialized designs to meet changing design requirements.

Design World editors recently asked a number of leading motor manufacturers about trends they’re seeing in the electric motor industry. Here’s what they told us.

Meet the experts
Dave Beckstoffer | Industry manager • Portescap
Jeff Coffed | Industry manager — aerospace and defense • Kollmorgen
Brian Dengel | General manager • KHK USA Inc.
Paul Denman | Applications engineer • Nippon Pulse
Ramon Guitart | VP of engineering — electric motors • Infinitum
Richard Halstead | President • Empire Magnetics Inc.
Mike Korkowski | Operations manager • LinMot USA
Robert Luchars | Executive VP • ECM PCB Stator Technology
Justin Reed | CTO • C-Motive Technologies
Artem Rogachev | Business lead — systems manager for motor drivers • Texas Instruments
Jonathan Spensieri | Product line manager • Kollmorgen

What’s changing about motor and gearmotor technologies?

Reed: One of the main disadvantages of gearmotors is the inefficiency of the gears; the only reason they’re needed is to fit the application’s torque and speed requirements with the motors that are available in the current market. Consequently, motor users add belts, pulleys, and gearboxes — paying an efficiency penalty to get the motor they want.

Electrostatic motors such as C-Motive’s technology can meet torque and speed requirements with direct-drive capabilities. This eliminates the gearboxes, inefficiencies, and added energy costs for motor users.

Dengel: As motor manufacturers move away from cylindrical output shafts with keys to D-shaped output shafts, end users are no longer able to use standard gears as the drive pinion. This change is forcing users to have custom gears made to match the D shape of the output shaft.

The miniaturization of motor technology is being driven by advancements in the machinery that produces motor components. Assembly equipment is also being automated, and that’s imparting the precision required to assemble motors having incredibly small diameters. In fact, the equipment producing and assembling small-size motors is utilizing motors that may have been considered quite small just a decade ago.

What must electric motors have to satisfy the rising tide of electric mobility?

Denman: Such motors must deliver programmable and precise profile moves, all controlled digitally — and must have minimal wear, so no contacting surfaces. Where rotary brushless dc motors are chosen, they need high resolution (often absolute) encoders with high torque-to-weight ratios for end effector and sample control. In many cases, they must have IP65 washdown capabilities.

Luchars: There are several features required of electric motors to meet the evolving demands of electric mobility. Most notably, electric motors for e-mobility systems must offer higher power density in a smaller package, greater durability, lighter weight, reduced noise, and provide design flexibility to optimize form factor. ECM PCB Stator Tech uses patented PCB Stator—printed circuit board—innovation and advanced Motor CAD to create next generation electric motors that incorporate these benefits for e-mobility systems. ECM’s PCB Stator electric motors are used as the central component for converting electrical energy to torque, horsepower, mechanical output, and forward motion in e-mobility applications.

In fact, our coupling of printed circuit board, axial flux motor topology to a SaaS platform represents a new technology tool for electric mobility. ECM’s PCB Stator electric motors are lighter, faster, quieter, and achieve much higher efficiencies than conventional machines. We connect that to our CAD software, PrintStator, which offers unprecedented flexibility to optimize electric motors for e-mobility systems.

PrintStator Motor CAD takes discreet inputs — how much torque, dimensional specs, desired rotation speed — and converts those into a design for a custom PCB Stator that’s used in axial-flux machines. ECM’s motor designs in axial-flux air-core machines have maximum torque and superior power in a much smaller footprint.

These attributes are highly beneficial to product designers in the electric vehicle and e-mobility space. The superior power density and high efficiency of ECM solutions enable extended battery life for integrated systems. Less mass means EV platforms have capacity for additional battery modules, further extending their range. An ultra-thin form factor and compact envelope allow these machines to integrate seamlessly as mid-drive, axial flux motors with little to no obstruction to other mechanical components.

Furthermore, ECM’s durable design contributes to increased system safety for e-mobility systems. Fully encapsulated motor windings prevent insulation failure, and the totally enclosed case makes ECM’s machines durable under extreme conditions. ECM’s motors are also acoustically quiet, meaning they generate less noise externally wherever an electric vehicle may operate.

What applications are ripe for automation with custom motor designs?

Guitart: Sustainable air-core motors that integrate variable frequency drives (VFDs) are bringing innovation and efficiency to conveyor applications. They can reduce energy usage by running the motor at lower speeds when possible. Advanced air-core motors replace the traditional motor’s stator, which is an iron core wrapped in copper wire, with etched copper wiring on a printed circuit board. In addition to improving the efficiency, the approach delivers better noise, reliability, and Internet of Things (IoT) connectivity. When a large-scale warehouse could have hundreds if not thousands of motors, the potential savings are significant.

In addition to cutting power bills, sustainable air-core motor systems offer improved reliability and can also help warehouse operators reduce the labor needed to maintain industrial equipment.

In a traditional iron-core stator, the operating heat produced by the load current through the copper wires expands and contracts the wire at a different rate than the steel core that holds it. Over time, the different expansion rates break the insulation, and the motor has failures to ground or coil to coil short circuits.

The components in Infinitum’s design have very similar coefficients of expansion. This makes Infinitum systems much more reliable, which is important for mission-critical facilities such as logistics and food handling, which can’t afford to have downtime.

Reed: Conveyors are much more prevalent in industrial facilities than people realize. Even for those aware of widespread conveyor use, the sheer quantity of motors driving conveyors within an industrial setting is astonishing. These conveyors contribute significantly to the overall energy consumption in industrial facilities. However, when the motor systems powering them operate at only 50 to 60% efficiency (primarily due to gearboxes reducing energy efficiency), it results in motor users paying higher-than-necessary energy costs. Additionally, the emitted heat necessitates improvements in HVAC systems to manage the increased heat being emitted by motors and gearboxes.

What recent motor innovations have benefitted the aerospace and defense industry?

Coffed: We’ve been supplying motion systems optimized for aerospace and defense applications for more than seven decades. Our motors, drives, and other motion products have always been of the highest quality, and that hasn’t changed. What’s new is that we achieved AS9100D certification in 2023. This certification provides documented assurance that the company’s quality-management systems comply with the high standards expected in the aerospace and defense industry. That is something end users can appreciate as they seek to identify the best motion partner for their mission-critical aerospace and defense projects – including rapid development in low-earth-orbit (LEO) satellites, space exploration, unmanned aerial vehicles (UAV), electric vertical takeoff and landing vehicles (eVTOL), and more.

Luchars: ECM has prototyped custom electric motors for electric motorcycles, bicycles, and scooters. In the marine and defense space, ECM collaborated with aerospace and defense company L3 Harris to design an electric motor for their IVER4 900 autonomous underwater vehicle.

Any new washdown-grade, explosion-proof, or specially certified motors?

Spensieri: Our newest product offering for the hygienic and washdown market is the AKMA servomotor. This IP69K-rated motor features a hardened anodized aluminum surface to offer machine designers a more cost-effective option when compared to stainless steel.

The lightweight design of the AKMA motor makes it easy to install and maintain, and its high torque density offers machine builders more performance in a smaller footprint. The motor is ideally suited for precision motion applications in food and beverage processing, pharmaceutical, and medical packaging operations.

Korkowski: We offer explosion proof motors (ATEX) suitable in 1/2 gas zones and 21/22 dust zones. These are completely encapsulated with an IP67 rating. We have stainless steel guide modules with IP69 /IP67S ratings. These can be easily assembled as fully washdown pick-and-place units. If you add a washdown gripper module, which is rated at IP67, this becomes a full washdown pick and place unit with gripper.

Spensieri: We recently expanded our offering of ATEX and IECEx/cETLus certified explosion-proof motors to cover high-voltage applications up to 480 Vac. These new explosion-proof approvals for the high-voltage Goldline EBH servomotor exemplify our commitment to advancing the state of the art in motion control and meeting the most demanding application requirements.

Explosion-proof motors are required in hazardous locations where flammable gases, mists, or vapors may exist in explosive or ignitable concentrations. Such environments are often found in mines, oil and gas refineries, textile mills, and industrial paint booths. Goldline EBH servomotors in frame sizes 1 to 6 join other explosion-proof motors in the Goldline EB family to meet ATEX/IECEx standards, and more specifically CE 0081 Ex II 2 G Ex d IIB T3 Gb –40ºC ≤ Ta ≤ 40ºC.

Any trends in the use of brushed and brushless motors?

Spensieri: There continue to be notable trends of various industries moving away from brushed motor technology to brushless designs. Brushless motors offer several advantages including higher efficiency, longer lifespan, and reduced maintenance requirements compared to brushed motors. Robotics is one of the most favorable industries for brushless designs because of their lightweight design, power efficiency, and improved reliability.

Beckstoffer: Brushed motors, specifically coreless motors, are being used more frequently in battery-powered applications based on their high efficiency, power density and lower weight. Combining high performance magnets with flux focusing housings is leading to an increase in output power in the same package. For brushless motors, new applications in the cardiovascular space are utilizing their high speed and reliability for surgical procedures to circulatory support.

Denman: New trends are in optical controls with high-resolution absolute encoders. Motors with high-resolution absolute encoders are replacing strain-wave gearing drives. We’re also seeing stages that are in HEPA biohazard chambers for high-performance liquid chromatography (HPLC) and drug-discovery spectrum analyzers.

Rogachev: Next-generation motor drivers are increasingly integrating more advanced functions for motor control, fault management, and sensing. These functions can significantly offload traditionally software-based functions, enabling a reduction in R&D software development efforts and more optimized MCU selections.

Of course, functional safety is an increasingly vital requirement for modern systems as smart motors and motor drives continue to proliferate into applications that closely interact with humans. Beyond factory settings, passenger vehicles and other automotive designs persist in delivering advanced functions for intelligent actuator controls in windows, doors, liftgates, seats, steering, and various other areas of the car where safety is a core priority.

Read the full article at Design World.