Unit 1
bus
bus
Unit 2
Unit 3
Unit
n
+
+
+
+
+
-
-
-
-
-
29
Figure 19. Corelation of dTmax as a function of I
rms
.
The estimation of dTmax can assist in determining if the IMD or IMR may be a constraint in operation. For example, in a hybrid power
application, the higher the charger current lower the operation time. However, with the thermal limits of the Evolion, one must
anticipate whether the dTmax of the Evolion will force too low of a limit for IMR or IMD.
If the expected environment temperature, in one part of the season, is 40 ºC and the calculated dTmax is 18 ºC, then the Evolion should
be anticipated to reach and stabilize up to 58 ºC at the end of charge. Constraints of IMR and IMD at this stabilized temperature should
be reviewed to make sure they do not limit operation by activating regulated charge mode (exceeding IMR) or open circuiting during
discharge (exceeding IMD).
13.3 Adding modules to existing bus
When adding an Evolion to an existing power bus, the maximum voltage difference for the modules to be added is 2 V from the bus set
point. This maximum allowed voltage difference prevents the inrush current sharing between modules to exceed 44 A and thus avoid
the charge regulated mode. See Figure 20.
Figure 20. Schematic of maximum allowed voltage
difference when connecting to existing
Evolion on a charged bus.
OPTION 2 – For any number of
direct
connected
Evolions, using the same
length of cable for each will make sure to
balance the resistance.
dV = 2V maximum
56 V
54 V
I
rms
dT max
0 5 10 15 20 25 30 35
35
30
25
20
15
10
5
0
dTmax (experimental measurements)
dTmax = 1.0549 (
I
rms
)
I
rms
=
1 cycle for example
I
2
Ch
+ I
2
Dch
t
Dch
t
cycle
t
Ch
t
cycle
Содержание evolion
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