Bulletin 2/2010 - Siempelkamp NIS

operating map which shows the operating point, the current
condition of the reactor (green cross hairs) in the image displaying
the power throughput and coolant fl ow rate. If the
operating point goes up, there is more power throughput without
increasing the coolant fl ow rate, therefore, more power
would be generated. However, the limit values would soon be
reached and the consequence would be an automatic shut down
of the reactor by inserting the neutron-absorbing control rods.
If the operating point shifts to the right, resulting in a higher
coolant fl ow rate without increasing the power throughput, the
fuel rods are cooled better, but less steam is generated, and
therefore less electricity. Therefore, the objective is to achieve an
optimal combination of fl ow-rate and power output which is
identifi ed by the blue curve (“URK-Nenn”) in the image.
In the current operating map, the reactor operator sees immediately
that the plant operates within the optimum range (marked
SIEMPELKAMP | NUCLEAR TECHNOLOGY
Plant cooling circuit schematic
with white backing) and knows that the operation is within the
limit values. At the bottom of the screen he can see the history
of the power output progression and can identify what tasks
were carried out by an earlier shift.
More in-depth information is available to the reactor operator on
demand: He can, for example, select a plant diagram which displays
entered, measured and arithmetic values. By clicking on a
numerical value, he can have a chronological sequence displayed
immediately and fi nd out how this value has changed over
time.
The plant diagram “cooling circuit” demonstrates in a simplifi ed
way how the coolant is heated inside the reactor, is turning into
steam (red), and is then fed to the turbine. Here the energy is
released, the steam condensates to water which is then fed as
water back to the reactor.