Consolidated Annual Report 2012 and Single-Entity ... - PVA TePla AG

Centralized energy generation and fixed distribution that
began with electrification around 130 years ago have become
a thing of the past. The grid of the future is no longer
a one-way street. The aim is to integrate and coordinate
many different decentralized sources with varying outputs
into a single system. The challenge is similar to that of the
internet revolution, except that instead of Web 2.0, we are
talking about eGrid 2.0! And with its vacuum heat treatment
furnaces, PVA TePla also plays a role in this segment.
These systems are used to manufacture components such
as vacuum circuit breakers, which are used to disconnect
or feed energy back into the grid. In flexible grids, this technology
is becoming increasingly important!
Vacuum Interrupters
GRID STAbILITY NEEDS INTELLIGENCE
Vacuum interrupters and circuit breakers are installed in
grids all over the world. They ensure the stability of the grid
in substations or municipal utility companies by switching
on power sources during periods of peak demand and
disconnecting them again in periods of low consumption.
Such a system is necessary to keep grid voltage at a stable
level. If more energy is fed into the grid than consumed
from the grid, voltage simply keeps increasing, posing a
danger to industrial and household appliances alike. Aside
from switching and disconnecting fed-in power, modern
circuit breakers also function as fuses in the event of short
circuits or overload.
The conversion of the power grid as part of the energy
revolution is giving these components an ever-increasing
significance. Due to the variety of energy suppliers, from
solar power producers to wind park operators, grid intelligence
solutions are having to become more advanced.
What is known as smart grid, the energy grid of the future,
is actually a highly flexible, consumption-driven distribution
system that organizes and coordinates an enormous number
of energy suppliers and consumers. As a result, energy
feed-in must be regulated at more and more points on the
grid in order to ensure that voltage remains constant.
SWITCHING IN A VACUUM
The principle of vacuum interrupter technology is almost
100 years old. The difference between vacuum switching
technology and conventional interrupter is that switching
takes place in a vacuum. As the switching process takes
place in a chamber that contains practically nothing, the
process is extremely reliable, maintenance-free and safe.
After all, when the supply is disconnected, there is no
ionizable material that could trigger a spontaneous thermal
arc discharge. Due to the high switching efficiency,
vacuum interrupter components can be made extremely
compact. There only needs to be a tiny gap between the
contacts to disconnect the flow of electricity reliably. This
level of efficiency remains stable over the entire lifecycle
of around 30 years. By contrast, the efficiency of oil, air
or sulfur hexafluoride (SF 6) interrupters is reduced every
time the switching process is triggered. This is primarily
due to the high voltages that occur in the interrupter’s contact
areas. In the medium voltage range, this can be as
high as 10,000 or even 40,000 volts. Each time the flow of
electricity is interrupted at such voltages, a small percentage
of the filling medium decays. This results in a loss of
efficiency. That is why the vacuum interrupter is superior to
filled components. However, the manufacturing of vacuum
interrupters is very complex. And that’s where PVA TePla
comes into play.
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PVA TePla in Focus