Motors and drives: Advantages of using adjustable speed drives
1 CERTIFIED PROFESSIONAL DEVELOPMENT HOUR (PDH) AVAILABLE UPON SUCCESSFUL COMPLETION OF AN EXAM.
The combination of a motor and adjustable speed drive (ASD) is called a power drive system (PDS). Specifying adjustable speed drives can help a manufacturing process become more energy efficient and productive. On variable torque applications (pumps and fans), one can expect energy savings of 20% to 40% with a PDS when compared to an application using a valve or damper for flow control.
Selection of the proper motor for a PDS will be discussed. Induction and synchronous motors will also be introduced. The new synchronous motor types are more efficient and offer a higher power density.
Electronically commutated motors are a type of synchronous motor technology and typically programmed for a single purpose at the factory because they are designed for specific use by the original equipment manufacturer (OEM). General-purpose drives can be programmed at any time to do whatever job is required.
Also, because of the wide range of capability built into ASDs, they are flexible enough to be programmed to not only satisfy the application required, and also to accommodate changes and be adjusted to fix problems and unexpected surprises.
- Learn the energy savings and process control available with adjustable speed drives
- Learn when to specify inverter ready or inverter duty motors.
- Review the applications for power drive systems.
- Understand what advantages a synchronous motor provides over an induction motor.
- Review applications in which each is applicable.
John Malinowski, Motor Industry Consultant, JMAL Consulting, Fort Smith, Arkansas
Tim Albers, IEEE Senior Member, NEMA MG1 Technical Committee Chairman, St. Louis
Amara Rozgus, Content Manager, CFE Media and Technology