User Manual

Page 61
EA Elektro-Automatik GmbH
Helmholtzstr. 31-37 • 41747 Viersen
Germany
Fon: +49 2162 / 3785-0
Fax: +49 2162 / 16230
www.elektroautomatik.de
[e-mail]
PSB 9000 2.5 kW Series
3.11 The function generator
3.11.1 Introduction
The built-in function generator (short: FG) is able to create various signal forms and apply these to the set value
of either voltage or current.
The standard functions are based on an arbitrary generator anddirectlyaccessibleandcongurableusingman-
ual control. In remote control, the fully customizable arbitrary generator replicates these functions with sequence
points containing 8 parameters each.
Other functions, such as IU, PV or FC are based on an XY generator that works with a table of 4096 values which
are either loaded from an USB stick or calculated based upon adjustable parameters.
Thefollowingfunctionsareretrievable,congurableandcontrollable:
Function Short description
Sine wave Sinewavegenerationwithadjustableamplitude,o󰀨setandfrequency
Triangle Triangularwavesignalgenerationwithadjustableamplitude,o󰀨set,riseandfalltimes
Rectangular Rectangularwavesignalgenerationwithadjustableamplitude,o󰀨setanddutycycle
Trapezoid Trapezoidalwavesignalgenerationwithadjustableamplitude,o󰀨set,risetime,pulsetime,fall
time, idle time
DIN 40839 Simulated automobile engine start curve according to DIN 40839 / EN ISO 7637, split into 5 curve
sequences,eachwithastartvoltage,nalvoltageandtime
Arbitrary Generationofaprocesswithupto99freelycongurablecurvepoints,eachwithastartandend
value (AC/DC), start and end frequency, phase angle and total duration
Ramp Generation of a linear rise or fall ramp with start and end values and time before and after the ramp
IU XY generator, USB stick loadable current curve (table, CSV)
PV, FC Functions to simulate a solar panel (PV function) or fuel cells (FC function), both with table
calculation based upon adjustable parameters, also for EN 50530
Battery test Battery discharge test with constant or pulsed current, along with Ah, Wh and time counters
MPP Tracking Simulationofthecharacteristictrackingbehaviourofsolarinverterswhenseekingtondthe
maximum power point (MPP) when being connected to typical sources such as solar panels
3.11.2 General
3.11.2.1 Limitations
The function generator isn’t accessible, neither for manual access, nor for remote control, if resistance mode (U/R
adjustment, also called UIR) is active.
3.11.2.2 Principle
The device features a built-in function generator (short: FG), but the entire unit can’t be considered as high power
function generator, because its power stages are only post-connected to the FG. Primarily in source mode, the
typical characteristics of a voltage and current source remain. Rise and fall times, caused by capacitor charge/dis-
charge,a󰀨ecttheresultingsignalontheDCterminal.WhiletheFGisabletogenerateasinewavewith1000Hz,
thedevicewillneverbeabletofollowthegeneratedsignal1:1.Sourceandsinkmodewillslightlydi󰀨erfromeach
other regarding the results, while the sink mode will be generally better, because primarily focused on current.
Depiction of principle: E󰀨ectoftheDCpowerstagesonfunctions:
FG PSB
DC
+
‐‐
C
The resulting wave on the DC terminal heavily depends on the frequency or period of the selected wave, its amplitude
andalsothevoltageratingofthedevice.Thee󰀨ectofthecapacitiesonthewavecanbepartiallycompensated.In
source mode and when running voltage dynamics to which the capacities have the biggest impact on it can help
to put an additional load to the DC terminal in order to decrease rise and fall times. This extra load has a positive
impact on periodic functions like rectangle or sine wave.