Page 9 - Energize March 2021

NEWS

Diesel generators in the data centre –

when is bigger better?

by David Matuseski, Cummins
inding the best combination
of generator size and system
Farchitecture is a goal for all
data centre designers. Many times, a
larger generator can provide unique
advantages. When you combine large
generators into a paralleling system,
you can achieve a whole new level of
advantages. The data centre designer
should carefully analyse all options to
optimise the generator system design. For all your advertising
There are many factors to consider
when designing the generator system requirements contact:
for your data centre. Two of the most
important items to consider in your design David Matuseski Katia dos Santos
are the optimal size of the generator and
the architecture of how your generators system. Various system architectures 076 410 6909
integrate into the overall power system. In have been developed to address this
some installations you have no choice but challenge. One of the more common katias@nowmedia.co.za
to go with a larger generator due to the size architectures is adding tie breakers (or
constraints of the site. sometimes tie switches) to the paralleling or
This can be especially true when bus. These tie breakers provide segments
installing additional power generation in the bus that allow you to partially shut Mark Yelland
into an existing building. Using a down the switchgear for maintenance.
greater number of smaller generators For example, if you have an N+2 074 854-1597
would not have been a good option design, you can completely isolate one
in this example. The higher power segment of switchgear for maintenance marky@nowmedia.co.za
density of large generators was the or repair. This design is also used in an
better choice. In addition to the unique N+1 design with tie breakers in-between
challenges in metropolitan areas, each generator on the paralleling bus.
sometimes the footprint advantages of The protective relaying on a segmented Visit our Website:
using large generators are also desired bus can be designed to eliminate the
in new construction. paralleling bus as a single point of failure. www.energize.co.za
Paralleling generators in a data centre This is most commonly achieved with a
design can have many advantages. It does current differential scheme.
not fit every situation, but paralleling Another way to achieve concurrent
does provide many benefits over a single maintainability is that each generator
generator design. The advantages have can be switched from one paralleling bus
varying degrees of importance in a data to an alternative paralleling bus. In an
centre application, but efficiency (reducing N+1 design, there would be one additional
your stranded generator power capacity), generator and corresponding transfer
can be the most attractive. The generator switch. Any one component, including
system is one of the more expensive the paralleling bus, can be shut down for
systems to procure, install and maintain. maintenance and there will still be the full
Making this system as efficient as possible ‘N’ capacity available from the generator
will have a significant effect on reducing system. There is another architecture for
data centre cost. paralleling generators being used in data
An important challenge in a centres. This is sometimes called ‘3 to make
paralleling system architecture is 2’ (or ‘4 to make 3’, etc.) n
achieving concurrent maintainability.
This is due to the common paralleling Contact Sbu Gule, Cummins Africa Middle East,
bus required in a generator paralleling Tel 011 451-3433, sbu.gule@cummins.com

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