A typical packaged substation supplied by Ellison
The Packaged Substation concept, whereby 11kV
Switchgear, Cast Resin Transformers, Low Voltage Switchgear and Automatic Power Factor
Correction equipment are close coupled to form a composite unit, was pioneered in the UK
by Ellison and today it remains one of the most significant advances in the distribution
of electrical power.
Any medium to large user of electricity is
always keen to find ways of economising in their electrical distribution system. There are
many costs savings to be made in both installing and running such a system. As an
example, a client was considering a distribution system that came with a price tag of
£650,000. After the system had been redesigned by Ellison into the packaged substation
arrangement , the total price fell to £475,000.
These savings arise for a number of
Transformer enclosures can be 'inline', '90°' or 'through busbar'. The modular cubicles
can then be arranged in any configuration to suit the application. Since they can have
through going busbars, there is no limitation on the number of transformers that can be
accommodated. This means the Ellison design is more compact than competing arrangements,
therefore saving floorspace and/or the cost of constructing large substation buildings.
Savings in the cost of
Since power is delivered at high voltage (and therefore low current) to the load points
and then stepped down, there is no need to install long runs of high current cable running
from a central transformer. There is a further saving since the much smaller diameter low
current cables will be easier to accommodate.
Significant savings in
Since there is no requirement for fire resistant walls, sprinklers or spillage
precautions such as draining pits and bunds, in the sub-station.
When the savings in running and
maintaining the system are considered in addition to those above, it is obvious why this
has proved such a successful product configuration.