Technology Watch: Optimal Solutions for Motor Control Drives Success

Optimal Solutions for Motor Control Drives Success

Achieve operational excellence and application flexibility with the latest control technologies

Motors cannot alter their speed, even for fixed speed systems, it is certainly difficult to find a motor that rotates at the right speed for its designated application. Therefore, variable speed drives are required to provide solutions that effectively manipulate voltage and frequency, with a wide range of power ratings for a diversity of applications.

Aiming to offer the best-in-class power and process control solutions, Rockwell Automation has introduced the latest and upgraded suite of drive solutions: Allen-Bradley® PowerFlex® 755T drives.

The new additions to the PowerFlex family help users reduce energy costs and increase machine uptime for assets running in high-demand applications.

All compliant to the IEEE 519 specification, and built with the patented TotalFORCE™ technology, the expanded drive portfolio includes the PowerFlex 755TL low-harmonic drive, PowerFlex 755TR regenerative drive, and PowerFlex 755TM common DC bus drive system:

  • PowerFlex 755TL Drive: Provides low AC input harmonics through the use of active front end technology and an internal harmonic filter to reduce harmonic distortion. The drive is available from 160 to 1250 kW
  • PowerFlex 755TR Drive: Provides an energy efficient solution that uses regenerative active front end technology to deliver energy back to the incoming supply. It also provides low AC input harmonics. This drive delivers power from 160 to 2,000 kW.
  • PowerFlex 755TM Drive System: Allows engineers to build the system that best fits their needs for regeneration and coordination of multiple motors in common bus configurations, so that energy consumption remains strictly matched with the requirement of the application. Predesigned modules are available with a power range from 160 to 2,000 kW.

The highly differentiated control technology in the PowerFlex 755T products keeps equipment running through most power quality disturbances with active front end ride-through control that regulates the DC bus voltage independently of the incoming AC voltage.

The high bandwidth motor control has a significant disturbance rejection and low tracking error while the excellent torque accuracy is responsive to torque disturbances and can function smoothly throughout operating range.

Besides, the predictive diagnostics help reduce unplanned downtime, hence can improve productivity. Operators can estimate and gain knowledge of the remaining life span of drive components, such as fans, blower, relay contacts and power semiconductors; parameters like temperature and runtime of the motors and drives can be monitored to allow for preventive action if necessary.

How it Works

With the next generation of Force™ Technology, PowerFlex 755T drives deliver superior electric motor control through precise adaptive control of velocity, torque and position.

The drives respond to production demands by comparing current performance to application settings, and making any necessary adjustments automatically. They communicate their performance data through the control to operation in real-time.

PowerFlex 755T drives continuously monitor their internal components and own activities.

During operation, the load observer and the adaptive tuning are responsible for monitoring the variables that can change over time, they will then automatically make adjustments to compensate for the mechanical changes as they occur, keeping the system performing as efficiently as possible.

Most importantly, the drives notify operators immediately about issues that might compromise drive or motor health. This level of self-awareness helps to significantly reduce unplanned downtime.

Premier Integration and Installation

The new PowerFlex drives are able to achieve an exceptional level of integration when the drives are used on an EtherNet/IP network. Configuring PowerFlex 755T drives with dynamic Human Interface Module (HIM), Studio 5000 Logix Designer® application or Connected Components Workbench™ software allows users consolidate controller programming and drive system configuration, operation, and maintenance into a single software environment, reducing programming time, simplifying startup and streamlining diagnostics.

In addition, their expanded uses of motion instruction within Studio 5000 environment allow device I/O capabilities to be assessed through the Logix controller. Such availability of general-purpose analog and digital I/O helps to reduce complexity and save engineering time.

Designed and built using a modular approach, the PowerFlex 755T drives offer the added advantage of fast and easy installation and maintenance with simplified management of spare parts.

The new drives’ design allows complete removal of a module from the cabinet, creating ample space for wire installation and allowing the power wiring to stay connected while the module is rolled out.

Therefore installation and maintenance are further simplified with an accessory cart that allows one person to easily insert or remove a module without the need for a ramp or hoist.

Safety Options Available

The Safe Torque Off option of the PowerFlex 755T drives, certified at SIL 3, PLe, Cat 3, removes rotational power to the motor without removing power from the drive for faster start-up after a demand on the safety system.

It makes integration of safety functions over EtherNet/IP possible. Such ability provides opportunities to reduce hardware and installation costs while improving productivity.

Likewise, for the drives, there is a Safe Speed Monitor option is certified at SIL 3, PLe, Cat 4. This option allows access to parts of the application while there is limited motion. In another words, operators can perform process or maintenance work without stopping the machine.

Powerful Performance. Flexible Control

Ask any heavy industry manufacturer about the top challenges they face, more than likely the answer will be reducing energy consumption, minimizing downtime and optimizing productivity. And they need to resolve these challenges while increasing profitability and protecting their investment.

“AC drive technology is an important investment for our customers, and they want their application up and running every possible minute,” said Brad Arenz, product manager, Rockwell Automation. “The PowerFlex 755T drives have been designed to provide savings from installation, through operation and maintenance with advanced features that allow you to optimize use of your assets.”

The PowerFlex 755T drive solutions are developed to provide the benefits that matter most to the manufacturers. The powerful new additions offer motor control along with cost-effective solutions for regeneration, low harmonics and common bus system configurations.

Latest News

Rockwell Automation and our partners offer exceptional knowledge to help design, implement, and support your automation investment.


Subscribe to Rockwell Automation and receive the latest news and information directly to your inbox.