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In the earliest electrical machines, solid iron cores were used, cast
or wrought, but the benefits of lamination in reducing eddy currents
rapidly became apparent.
Higher magnetic grades of steel which improve efficiency must
be included as a major factor considering the urgent need to diminish
wastage of energy, conserve finite resources and reduce the release
of pollutants. Improved higher grades of steel also enable machines
to be reduced to more manageable sizes.
Reduced size is clearly associated with reduced energy wastage
in exciting conductors. In pursuit of a greener world there is a pressure
and interest in pumps, fans and other drives to use speed control which
improves efficiency and reduces waste. Speed control throttling of
the output, a very wasteful practice, can be avoided. The means of
speed control offers fresh challenges to the motor manufacturers to
accept a wide range of input frequencies without themselves creating
excessive losses.
High speed motors mean smaller and lighter machines, able to de-
liver increased power output, lamination steel and Variable Frequency
Drives (VFDs), critical to achieving these benefits.
Transformer lamination steel
In the past 70 years the development in lamination steel, as well as
amorphous alloys, has reduced the losses significantly.
Transformers for power distribution experience two pressures.
The first is for reduced first cost to fit in with short term budgeting;
the other is to be super efficient so the life time ownership costs
are minimised and green performance optimised. In the early 1940s,
losses in conventional grain-oriented steel at 1,7 Tesla were around
Engineers… does the ‘Solar Sphere’ improve collection of solar power?
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ENERGY EFFICIENCY MADE SIMPLE 2015