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PSI 9000 2U Series
EA Elektro-Automatik GmbH
Helmholtzstr. 31-33 • 41747 Viersen
Germany
Fon: +49 2162 / 3785-0
Fax: +49 2162 / 16230
3.9.3 Two quadrant operation (2QO)
3.9.3.1 Introduction
This way of operating refers to the use of a source, in this case a power supply
of this series PSI 9000 2U, and a sink, for example a series ELR 9000 electronic
load. The source and the sink function alternately in order to test a device, such
as a battery, by deliberate charging and discharging as part of a functional or
final test
The user can decide whether the system is operated manually or the power
supply only as the dominant unit or both devices should be controlled by PC.
We recommend to focous on the power supply, which is intended to control the
load’s behaviour regarding voltage and current via the Share Bus connection.
Two quadrant operation is only suitable for constant voltage operation (CV).
Clarification:
U+
U-
I+
I-
I
II
III
IV
A combination of source and sink can only map the quadrants
I + II. This means that only positive voltages are possible. The
positive current is generated by the source or application and
the negative current flows into the load..
The maximum approved limits for the application should be set
in the power supply. This can be done via the interface. The
electronic load should preferably be in operating mode CV. The
load will then, using the Share Bus, control the output voltage
of the power supply.
Typical applications:
•
Fuel cells
•
Capacitor tests
•
Motor driven applications
•
Electronic tests where a high dynamic discharge is required.
3.9.3.2 Connecting devices to a 2QO
There are a number of possibilities to connect source(s) and sink(s) to make a 2QO:
Share
-Bus
E.U.T
E-LOAD
PSU
Configuration A:
1 e-load and 1 power supply, plus 1 test object (E.U.T).
This is the most common configuration and the least prob
-
lematic.
The nominal values for U,I and P of the two devices should
match, such as ELR 9080-170 und 3x PSI 9080-60 2U (paral-
lel connection with total current of 180A).
Share-
Bus
E.U.T
E-LOAD
PSU 1
PSU n
Mast
er
-S
lave
Configuration B:
1 e-load and multiple power supplies, plus 1 test object
(E.U.T).
For adapting the total power of the power supply on the pos-
sible higher input power of the load. The power supplies are
connected via Master-Slave and the load current is shared
across the power supplies.