© EPS Stromversorgung in 2022, this information is subject to change without notice
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30000800_manual_psb_10000_4u_30kw_en_04
3.11.14
FC table function (fuel cell)
3.11.14.1 Preface
The FC table function is used to simulate the characteristics of volt-
age and current of a fuel cell. This is achieved by setting up some
parameters which define points on a typical fuel cell curve, which is
then calculated as UI table and passed to the internal function gen-
erator.
The user has to adjust value for four support points. The device will
request to enter them step by step, indicating the actual point on
screen with small graphics. When finished, these points will be used
to calculate the curve.
Generally, following rules apply when setting up those values:
•
U
OC
> U
Point2
> U
Point3
> U
Point4
•
I
SC
> I
Point3
> I
Point2
> I
Point1
•
Values of zero are not accepted
In order to express the rules in a simplified way: the voltage has to decrease from point 1 to point 4, while the current has to
increase. In case the rules are not followed, the device will reject the settings with an error and reset them to 0.
3.11.14.2 Usage
The following parameters can be set for the FC table function:
Parameter
Range
Description
Point 1: Uoc
0 V...U
Nom
Maximum voltage of the cell (open circuit voltage at no load)
Points 2+3: U
0 V...U
Nom
Voltage and current define the position of these two points in the XY coordinate system,
which represent two supporting points on the curve to be calculated
Points 2+3: I
0 A...I
Nom
Point 4: Isc
0 A...I
Nom
Maximum output current of the fuel cell (short-circuit situation)
U
0 V...U
Nom
Global voltage limit, should be ≥Uoc
P
0 W...P
Nom
Global power limit, mustn’t be 0 to have the function run as expected
All these parameters all freely adjustable and it may occur that the curve calculation fails. In such a situ-
ation, the device would show an error. Then you are required to check the settings, adjust and try again.
Schematic diagram:
Application and result:
I
U
U
oc
Isc
P2
P3
P1
P4
After setting up the four supporting points Point 1 thru Point 4, whereas Point
1 is defined by Uoc and 0 A and Point 4 is defined by Isc and 0 V, the device will
calculate the function as IU table and load it to the XY generator.
Depending on the load current, which can be between 0 A and Isc, the device
should set a variable output voltage between 0 V and Uoc, resulting in a curve
similar to the one depicted to the left.
The slope between Point 2 and Point 3 is depending on the values adjusted
for Point 2 and Point 3 and can be freely modified as long as Point 3’s voltage
is lower than the one of Point 2 and Point 3’s current is higher than the one of
Point 2.
►
How to configure the FC table
1.
In the function generator menu tap on group
FC table (PS)
.
2.
Adjust the parameters of the four supporting points, as required for the simulation.
3.
Do not forget to adjust the global limits for voltage and power in the next screen which reach by tapping on
.
4.
After setting up everything proceed to the main function generator screen with
. After the function has been
loaded to the internal XY generator, the simulation is ready to start.
