At NMW this week, SEW-Eurodrive, explored the latest revision to the Minimum Energy Performance Standards’ (MEPS), with respect to electric three-phase induction motors.
Presented by SEW-Eurodrive engineering manager, Frank Cerra, the seminar provided attendees with an in-depth analysis of the evolution of MEPS, and highlighted how the latest changes impact Australia’s manufacturing sector.
The presentation saw Cerra illuminate a number of key areas. These included an overview of MEPS standards and legislative requirements, and the effects of improved efficiency on motor design and selection. Cerra also explored application considerations and total drive system efficiency, and future directions in motor efficiency.
MEPS legislation has governed the use of electric motors in Australia since the Australian Greenhouse Office (AGO) introduced the system in 2001. In April 2006, however, the mandatory standards were revised upwards. A more stringent set of requirements, known as ‘MEPS 2006’ or ‘MEPS2’, was published and came into force. The ruling is mandatory and applies to all two-, four-, six- and eight-pole electric squirrel-cage induction motors ranging from 0.73 to 185kW.
“With the introduction of MEPS2006, Australia is now one of the world leaders in regulating electric motor energy efficiencies,” said Cerra. “There is now wide acceptance of the standard within the Australian manufacturing sector, with the majority of motor users specifying MEPS-compliant motors when purchasing.”
Attendees were encouraged to leverage Cerra’s MEPS expertise in his role as Chairperson of the Rotating Machinery Forum of the Australian Industry Group, and invited to ask questions in a discussion-based forum held at the end of the presentation. “The discussion session provided insight into the real-world MEPS-related issues facing Australian manufacturers,” said Cerra. “The MEPS issue is obviously a complex one, with a multitude of implications that reach across a range of industries.”
Cerra also highlighted the research and development work being undertaken by global industry bodies that goes beyond the bounds of the electric motor itself. This work is exploring the domain of what is often described as ‘total drive efficiency’. “While current MEPS-compliant electric motors achieve efficiency improvement over old ‘standard’ efficiency motors, it is valuable to see how such figures sit within the context of a total drive train efficiency upgrade,” said Cerra. “While MEPS compliance is vital, it is equally vital to look beyond the motor itself and consider the drive train as a whole.”
The electric motor statistics that most clearly point the way for future developments are, surprisingly, those that talk more of the total life-cycle economics of the electric motor, rather than any resultant reduction in megatonnes of greenhouse gases. “This suggests that the performance-class of the electric motor–and the design of drive train to which it is coupled–need to be carefully selected and implemented,” said Cerra. “The very nature of the technology applied, both at the motor level and across the total drive train, could have huge ramifications both environmentally and economically.
“The next major challenge will be to address these total life-cycle/total drive train efficiency issues. This, then, is an important direction for electric motor MEPS development as we go forward.”