New drive products are literally at the crossroads in the latest control systems, offering both expanded control capabilities and more sophisticated support for different types of motors. They are expected to provide better power efficiency and continue to expand their role in intelligent, distributed control architectures.
The end result is that drives utilizing new processors, Ethernet technology and advances in control algorithms are providing greater power efficiency, distributed control and more sophisticated operation, while also balancing the need for lower cost solutions.
“A main trend in drives is power efficiency,” says Craig Nelson, drives product manager for Siemens Energy & Automation. “With new aluminum rotor motors, drives with regenerative capabilities, customers adapting to common dc bus and active front end, engineers are looking at anything that helps increase the power efficiency of systems.”
Nelson says the focus on power efficiency also relates to the larger goal of reducing costs, so there is an emphasis on modular drive systems and separation between the power and the controller which allows customers to get better price/performance for applications.
David Greensmith, Baldor's product manager for Ethernet Motion Products, says processor power in the drives has also been used to support more sophisticated control functionality.
“One trend in drives is the use of more direct drive motors, which is influencing the motion control algorithms along with interior permanent magnet motors which are gaining interest in the marketplace simply because of the efficiency benefits that they offer,” he says.
Greensmith says these developments require more complex motor control algorithms as vendors offer software-configurable products with capabilities to control additional motor types. The same drives can be used to control rotary brush and brushless motors and closed-loop vector control of ac induction motors.