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issue: October 2009 APPLIANCE Magazine
Cover Story: Motors and Air-Moving Devices
Motors Moving Forward |
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Motors manufacturers are looking beyond gloomy economic times to the high-efficiency future.
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Dyson’s DC31 handheld vacuum is powered by the new V2 motor, designed by the company’s in-house motor engineering team to operate at up to 104,000 rpm.
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As of this time last year, the global economy
was entering its deepest recession since the post WWII-era. In the
United States, once-strong housing sales plummeted, stock prices fell,
and financial institutions crumbled. One year later, economic
conditions are showing signs of improvement. In late September, Federal
Reserve Chairman Ben Bernanke said that the recession was “very likely
over.” Many people breathed a sign of relief, albeit a cautious one.
No
one expects a quick recovery. Given that the recession was caused
largely by a financial crisis, the process of economic recovery will be
slowed, some economists suggest, because households and businesses will
need time to work off what became unsustainable levels of debt. Job
growth typically lags behind other signs of improvement after
recession, and it could be many months before the job market starts
improving. While segments of the U.S. economy such as homebuilding and
consumer spending are showing signs of stabilization and very slight
growth, others such as nonresidential construction activity are showing
no measurable improvement or even continuing to worsen.
Motors
manufacturers certainly felt the downturn. The U.S.-based National
Electrical Manufacturers Association’s Motors Shipments Index declined
for the third consecutive quarter in 2Q 2009, contracting 10.5%
compared with the first three months of this year and nearly 25% versus
2Q 2008. After climbing sharply to a cyclical peak in 2006 and
remaining at a high level through mid-2008, the NEMA said the index has
plunged 28% in the past nine months and is now at its lowest level
since the beginning of 2005. Demand for both fractional and integral
horsepower motors weakened, with both categories registering large
year-over-year declines in shipments.
That
fall in the Index follows a decline for 1Q 2009, in which NEMA reported
a 9% drop versus 4Q 2008 and 23.4% on a year-over-year basis.
Fractional and integral horsepower motors both saw market demand
weaken, but the decline in fractional units was appreciably weaker
compared with 1Q 2008.
NEMA—like most other
watchers of the economy—believes a modest recovery is within sight. It
expects its Motors Shipments Index to decline through the end of 2009
before beginning what should be a tepid rebound.
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 S-Force Radial Blowers are equipped with a new high-powered motor that enables it to reach performance levels not yet seen in the market. ebm-papst Inc. (Farmington, CT, U.S.; www.ebmpapst.us) engineered the blowers with nominal speeds of up to 4600 rpm and airflow of up to 988 cfm. The S-Force radial blowers are standard with PWM control input and speed signal. Optional features include speed monitoring, closed-loop speed control, operating monitoring, integrated or external temperature sensor, or microprocessor-controlled motor management for software-controlled operation.
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Saving Money and Energy
The
economy has made consumers more cost-conscious, and their frugality is
not going to evaporate, even when the recovery is in full swing. This
new outlook is driving new housing trends. In the United States, new
homes are being made smaller to be more economical. The appliances that
go into these new homes, even if they are premium appliances, have to
have benefits and features that appeal to the new attitude of
thriftiness.
So what do appliance OEMs want from their motor suppliers?
According
to John Morehead, vice president of strategic planning and marketing
for Bison Gear & Engineering Corp. (www.bisongear.com) in St.
Charles, IL, U.S., “The holy grail remains the same: more power in a
smaller package, longer maintenance-free life, and lower cost.”
Commercial
appliance makers are particularly cognizant of the cost of
inefficiency—and the cost of every square foot of real estate. “It’s
understandable…when you realize that with more fast food restaurants
operating 24 hours a day that their energy costs are an increasingly
important expense,” Morehead says. “With quick serve restaurants
expanding their menu offerings, while maintaining the same footprint,
it’s critical that our customers are able to reduce the size of their
equipment. Downtime in fast food is not only costly from the skilled
repair labor standpoint, but can be devastating to an operation’s
customer following and profits.”
Bison is a
supplier to many commercial foodservice equipment makers, and Morehead
says it is crucial for them to understand their customers’
customers—the restaurateurs. “That helps drive our own product
development and manufacturing improvement initiatives.”
The Difficult Question of Cost
Cost
is a complex equation in the motor industry, in part because of raw
material prices. “As soon as copper goes down, steel goes up or
vice-versa,” Morehead says. He says components from low-cost countries
like China have been subject to price increases that are greater than
those that have been necessary in North America and Europe in the past
12–18 months.
Price decreases are always on
the minds of motors buyers, but not always No. 1 on the priority list.
“While purchasing departments will continue to parrot the lower cost
request, we find that increasingly they want their motor and gearmotor
suppliers to add value by actively participating in their design teams.
This has been enhanced due to overall corporate down-sizing as well.”
Julie
Heinrichs, marketing manager, Heating, Ventilation, Air Conditioning,
and Refrigeration for A. O. Smith (Tipp City, OH, U.S.;
www.aosmithmotors.com), says that motor costs will continue to drive to
lower levels. Still, the major reductions will be in the overall system
cost reductions. “Lower global costs are what our customers request on
a day-to-day basis,” she says. “A. O. Smith’s global manufacturing
facility footprint in Asia, Europe, and North America helps manage
costs on a worldwide basis. Material cost fluctuation of copper,
aluminum, and steel has significantly impacted price globally over the
past six years.”
Heinrichs says that when
appliance OEMs are still looking for motors and blowers that are quiet,
energy-efficient, innovative, and cost-competitive, “the solution
sometimes comes with the most cost-competitive product, but many times
equates to an innovative, energy-efficient system solution that not
only saves our customer money, but saves the end-consumer energy,” she
says.
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 A. O. Smith’s iMotor evaporative fan replacement provides refrigeration energy savings.
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Energy Savings/Cost Savings
Because
the motor is often the biggest energy-using component in an appliance,
increasing efficiency is key to designing and manufacturing new
appliance motors. Motor suppliers are ramping up their efficiency
R&D. For example, A.O. Smith is expanding its engineered approach
to achieve increased energy efficiency applied to its blowers and
motors. Mike Metzler, general manager for Heating, Ventilation,
Air-Conditioning, and Refrigeration for the company, says, “Integrated
and remote electronics are being applied to HVAC/R applications. A. O.
Smith is maximizing the design and materials going into
energy-efficient motors and blower systems.”
Oftentimes,
making the appliance more efficient means transitioning to new motor
types. Integrated circuit (IC) supplier Allegro MicroSystems Inc.
(Worcester, MA, U.S.; www.allegromicro.com) is helping customers
re-engineer their appliance models to replace their ac motors with
variable-speed dc motors, using inverter motor driver ICs. “For some
models, the appliance makers expect their energy efficiency rate to go
up by over 300%,” says Allegro’s Stephanie A. Fennelly. “These ICs
incorporate three pairs of high-side and low-side IGBTs inside one
package. In comparison with designing with discrete components, these
ICs allow the appliance makers to reduce the design to market time and
minimize the use of product design resources that are in short supply.”
Fraser
McHenry of Freescale Semiconductor (Austin, TX, U.S.;
www.freescale.com) explains that his company is helping appliance OEMs
meet energy efficiency needs through its portfolio of microcontrollers
(MCUs) and digital signal controllers (DSCs) that enable more-advanced
energy-efficient motor control solutions. The portfolio starts with
entry-level 8-bit MCUs for cost-sensitive applications such as fans,
pumps, and compressors. The MCUs have dedicated PWM (pulse width
modulation) modules with integrated analog digital convertors and
high-speed comparators to provide fast, efficient control of the
inverter stages without CPU intervention.
The
next level includes a family of 16-bit DSCs with dedicated motor
control peripherals for advanced appliance applications such as
variable-speed compressor control, or sensorless BLDC motor control.
“DSCs with MAC instruction sets can perform high-speed accurate
positional vector control of three-phase motors,” he says. “Freescale
also has a dedicated systems team developing advanced motor control
algorithms to help manufacturers get the best efficiency performance
from their designs.”
Bison also employs what
it calls Robusticity design principles to help it develop gearmotors
that won’t fail within the life of a customer’s product. The supplier
is adding more three-phase ac motors to its fractional-horsepower
gearmotor offering because they offer inherently higher efficiency than
single-phase models. “In that regard, more of our customers are
designing their equipment for three-phase power or are employing
variable-frequency drives with single-phase power so they can run
three-phase motors and have the additional energy saving benefit of
variable speed,” says Morehead. The company is also introducing new
brushless dc gearmotors and continues to develop gear trains that are
more efficient than existing alternatives. “For example, our offset
parallel-shaft gearmotors utilize helical gearing that is much more
efficient than the traditional right-angle worm gears they often
replace…sometimes less than 50% efficient.”
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Bison’s 500 Series parallel-shaft ac gearmotor is designed for applications requiring robust torque, such as ice machines.
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Greener Motors
Appliance
companies are embracing “green” even if there is, as yet, no
hard-and-fast definition as to what constitutes a green product. Making
an appliance more energy-efficient is an obvious and significant step,
but it’s just one slice of the environmental pie. There is opportunity
and need for motors to be part of the sustainability solution.
“A.
O. Smith has seen the push for ‘green’ motors, just as the industry has
for green appliances,” says Heinrichs. She points to restrictions that
have limited the use of certain materials. The RoHS (Restriction of
Hazardous Substances) and REACH (Registration, Evaluation,
Authorization and Restriction of Chemical substances) regulations have
become law in Europe, naturally having an impact on suppliers in the
region that use any of the controlled materials. Similar materials use
restrictions will undoubtedly proliferate worldwide.
“A.
O. Smith sees an even greater push in the future, and has taken
aggressive steps, going beyond the SVHC list of substances listed in
the REACH Guidance,” says Heinrichs. “We are working to eliminate or
regulate quantities allowable by ROHS for prohibited and declarable
chemicals (listed in the GADSL). We believe these regulations will
quickly become global standards.”
On the
environmental front, meeting substance restriction standards may be a
far easier challenge than the issue of recycling, which is likely to
become a requirement in more markets worldwide. Morehead of Bison
notes, “By their nature, electric motors are not easily broken down
into discrete component commodity materials for recycling.” Bison, he
says, is engaged with the Electric Motor Education & Research
Foundation (EMERF). The organization is mounting a collaborative
pre-competitive research program with American motor manufacturers to
address not only end of life, but also production costs and increased
energy efficiency to further the global competitiveness of the small
electric motor industry.
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Models ECR 82P and 92P are electronically commutated motor (ECM) refrigeration motor fans with the same exterior design as 5-W shaded pole motors, but engineered for higher efficiency and power. Wellington Drive Technologies (www.wdtl.com) says the motors are the first to be enclosed in a body of advanced polymers, giving them high moisture resistance in refrigeration and vending applications.
