Members of the National Electrical Manufacturers Association (NEMA) Motor and Generator Section and the European Committee of Manufacturers of Electrical Machines and Power Electronics (CEMEP) recently discussed a new direction for global motor efficiency standards. Once isolated system components, these standards are evolving in scope into interconnected, multi-component systems to achieve greater energy savings than have been realized with previous motor efficiency regulation.
In a joint white paper, New Systems Approach to Motor Efficiency Standards Promises Electrical Energy Savings in Practical Applications, to be presented at the Motor Summit 2016 in Zurich on October 11 and 12, NEMA and CEMEP outline an extended product approach that moves beyond single motors, invertors, and controls to include electronic speed controls, power drive systems (PDS), pumps, fans, compressors, and other auxiliary electronics that make up the system.
“We believe the market will embrace a new systems approach to power drive standards that quantify total energy savings in place of efficiency for isolated components,” said Robert Boteler, of Nidec Motor Corporation, who chairs the NEMA Motor and Generator Section Energy Management Committee.
“The motor is a critical part of any electronic system, but it only makes up a small percentage of the energy losses inherent in any electrical system,” said CEMEP President Jurgen Sander. “Incorporating power drive systems can increase energy saved by as much as six times the amount that could be saved when relying solely on the motor component.”
Motor efficiency classification in Europe started in 1998. In the U.S. in 2001, motor manufacturers raised efficiency levels above the minimum requirement that Congress had established in 1992. In 2010, this premium efficiency level was added to regulations, establishing it as the minimum requirement. This brought greater savings to a select category of motors known as subtype 1 and subtype 2. These market categories make up approximately 40 percent of the units sold each year.
In 2014, the most recent round of U.S. regulations was released. It takes effect June 1, 2016, and covers all polyphase motors from one to 500 horsepower (or .75 to 375 kilowatts).
Currently, the NEMA-CEMEP working group is developing a new standard that uses loss reduction versus efficiency when considering total system energy savings. The joint group is also establishing the losses generated at various operation points and determining the savings in energy as a result of using a power drive system. The resulting standard will establish a series of points that can be used to evaluate and optimize energy savings.
“We believe the market will embrace a new systems approach to motor efficiency standards,” said Boteler. “This will enable us to measure and minimize power losses for all segments of the motor-driven market.”