By Lisa Eitel | ❇️

The last decade has seen advancements in controls and motor drive technologies to boost efficiency, safety, and ease of use. Now commonplace are drives that:

• Let end users leverage autotuning functions for faster commissioning
• Detect and correct for vibration issues — including the shaping of power into motors to avoid resonances
• Spur increasingly compact motors to beyond rated speeds
• House sensing capabilities and memory to support predictive maintenance initiatives
• Perform realtime monitoring for continual efficiency optimization
• Sport safely limited speed and safe-direction features.

Controls on the other hand are the basis of software-based automation in applications requiring flexible solutions for frequent changeovers; digital-transformation connectivity; and distributed control using ruggedized control components. We recently asked industry experts for their own observations and insights into the most important drive and control trends today. Here’s what they had to say.

T. Burke: Products in general are becoming more sophisticated and competitive. For example, servodrives are now equipped with torque measurement and encoder technology that is so accurate that it can automatically detect vibrations, manage acceleration, and deceleration. At the same time, improvements in components and manufacturing processes are delivering greater tolerances and quality in hardware. In the case of communications, the latest technology is gigabit Ethernet and the ability to schedule communications through time sensitive networking (TSN). CC-Link IE TSN is a leading performance industrial Ethernet network technology available in a broad range of vendor products.

Worsnopp: Two trends in servodrives we’re seeing include ease of integration and advanced safety. From the sizing and selection of servos to their configuration and programming, machine builders today expect the use of servodrives to be easier than ever. After all, we’re all surrounded by consumer technology such as smartphones, smart TVs, and cars that are exceptionally easy to use. This leaves us all with the impression that technology should be accessible. Manufacturers have also improved servodrive buying processes. For example, Festo provides easy-to-use tools for sizing servo axes and configuring their servodrives along with function blocks to simplify servodrive programming.

Guitart: Rockwell Automation and Infinitum are jointly developing a motor system combining Rockwell’s PowerFlex drive technology and Infinitum’s high-efficiency Aircore EC motor system. The solution aims to help companies reduce their carbon footprint with a motor system that’s 50% smaller and lighter than traditional iron-core motors all while using 66% less copper and consuming 10% less energy. The motor and low-voltage drive solution will be distributed through Rockwell to let global industrial-sector clients deploy a sustainable motor system and cut energy consumption.

Worsnopp: It is still early in this trend, but we are seeing more requests for servodrives that incorporate advanced safety functions such as safe limited speed. Historically, servodrive safety was implemented outside the servodrive using safety relays and safety controllers. Over time, more safety functions have integrated into the servodrives themselves; this in turn saves machine builders time and increases machine reliability. For example, safe torque off (STO) is now a standard safety function included in many servodrives. STO makes it possible for the machine builder to easily cut power to the motor … and that makes it safer for an operator using the machine.

As automation becomes more sophisticated, machine builders are likewise requiring more advanced safety functions that let them run their machine and reduce the risk of harming personnel. For example, with safe limited speed on a servodrive, it’s possible for machine builders to keep a machine in motion (typically at a safe reduced speed) and monitor that speed to ensure it’s prevented from accidentally moving too fast.

Advanced safety functions are becoming more common on servodrives, and we can expect to see more manufacturers offer them in the future.

Korkowski: LinMot’s Multi-Interface drive is compatible with Ethernet IP, PROFINET, EtherCAT, Powerlink, SERCOS, and CC-Link. As a single product to satisfy multiple designs, this drive offers quick lead times. Our drives also feature process monitoring for pass or fail and force control as a software solution to support various design options.

Ledoux: We are seeing an increased demand in motor speed controllers to be installed in remote areas requiring outdoor packaging dedicated to the component instead of what is typically provided — a climate-controlled building.

Guitart: Integrated motor and drive solutions from Infinitum are making installation and serviceability in the field easier … and improving uptime and equipment reliability. For instance, new designs feature user alerts that identify specific problems for faster resolutions as well as removable access panels for easier access to terminals, connectors, and programming ports.

With conventional motors, it can take up to two weeks to have service requests fulfilled. New Infinitum motors are built for end user serviceability. Infinitum can train a company’s internal technical service team to do repairs in about 15 minutes, so end users have more control and flexibility. In data centers and manufacturing lines where uptime is of key importance, this is a desirable and differentiating capability.

Luchars: ECM recently launched an integrated and customizable electric motor controller — a 5-kW Unum Potentia controller leveraging PCB Stator and PrintStator Motor CAD platform while helping deliver 98% efficiency. When combined with a PrintStator-designed machine, the controller allows IE5 ultra-efficiency electric-motor performance. With a near-100% efficient controller versus one having 80% to 90% efficiency, the system consumes less energy than traditional alternatives. The new motor controller will be available to PrintStator SaaS clients and partners for roughly a tenth the cost of controllers supporting similar electric-motor kW ranges. With this controller, engineers can fully integrate PrintStator designs and design a drive-controller perfectly tuned to the full electric system.

PrintStator software allows the custom design, manufacture, and integration of PCB Stator electric motors. The motor controller is customizable via PrintStator and structurally and thermally integrated to the resulting motor housing for a compact footprint (and full motor-system optimization). In fact, the software can output motor-tuning parameters and translate those into a code file that uploads to the controller. This makes the motor system design truly plug and play. The controllers can run 3 to 8-kW motors with board-component changes; the board footprint always stays the same. The Unum Potentia motor controller also operates on a 220 and 480 three-phase ac supply; offers sensorless control capable of running motors down to about 50 rpm; and (with its FETs) can switch upwards of 100 kHz.

With encoders so essential to motor drive systems for position feedback, velocity control, and error correction, safety capabilities, and diagnostics, it’s no surprise their design and application have advanced as well. Here’s what four industry experts had to say on this.

Brimage: Encoders provide realtime feedback on load position, which is critical for high-precision, linear motion applications. We’ve seen increased application of encoders due to linear motion systems requiring more precision than ever. The demand for high-precision systems in medical, life sciences, and factory automation is saddled with demand for more compact systems as well.

Beckstoffer: Motor feedback is always critical in medical applications, particularly drug-delivery devices, to ensure accurate dosing to the patient. With these devices getting smaller to enable patient mobility, feedback devices must continue to shrink in size while providing the proper counts per revolution. Magnetic encoder technology is allowing the size reduction for closing the loop for dc motors.

Brimage: In support of the industry pushing toward miniaturization, we have also seen an increased demand for smaller encoders. Thomson has a complete offering of stepper motor linear actuators with integrated encoders to enhance precision positioning control with a range of sizes that are compatible with small motors.

Soltero: We’ve observed a trend towards absolute encoders with analog outputs to help systems efficiently handle higher resolutions. In some cases, when customers seek to increase the resolution of their existing incremental encoder designs, they typically use a higher pole-count ring magnet (if one is currently used) as well as digital-output Hall-effect latches. This combination is employed because higher pole-count magnets produce a weaker magnetic field, necessitating a high-sensitivity Hall-effect latch. At some point, the design reaches a limit on the number of poles due to costs associated with the magnets and latches. Once this limit is reached, designers typically transition to absolute encoders with analog outputs.

Graham: The latest trend we’re seeing in motor feedback is encoders assuming more sensing tasks with a common communication channel back to the drive-control system through the encoder interface. Things such as temperature sensing, vibration sensing, and torque sensing are all possible to do with the integration of certain encoders. As we move to support these features, we’ve also improved our communication interface with EnDat 3.

MEET THE EXPERTS
Dave Beckstoffer | Industry manager • Portescap
Kurt Ledoux | Business director — medium voltage drives • Yaskawa
Lindsey Brimage | Product line manager – lead and acme screws | Thomson Industries
Manny Soltero | Product marketing engineer • Texas Instruments
Mike Korkowski | Operations manager • LinMot USA
Ramon Guitart | VP of engineering — electric motors • Infinitum
Robert Luchars | Executive VP • ECM PCB Stator Technology
Stuart Graham | Business Development Specialist • HEIDENHAIN Corp.
Thomas Burke | Global strategic advisor • CC Link Partner Association (CLPA)
Tom Worsnopp | Product market manager – electric automation • Festo

Read the full article at Design World.