Example Diagram Of Generator With Transformer Inverter - Phoenix Contact SCK-C-MODBUS User Manual

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As illustrated in the example below, this results in the following possible voltage levels in the
system:
1000
800
600
400
200
0
-200
-400
-600
-800
1
Figure 2-3 Voltage ratio with and without transformer
1: Transformerless inverter
2a: Inverter with transformer, without grounding
2b: Inverter with transformer, with grounding at negative pole
2c: Inverter with transformer, with grounding at positive pole
The diagram also clearly shows that using transformerless inverters can mean that the total
PV generator potential oscillates to ground, even though the generator voltage itself sup-
plies a DC voltage.
In the case of transformerless inverters, it should also be noted that there is no electrical iso-
lation to ground here. This is particularly important if devices are incorporated in the system
which are only intended for IT systems, i.e., they have no ground connection.

Example diagram of generator with transformer inverter

Figure 2-4 Example diagram of generator with transformer inverter
2a 2b
H-Bridge
Filter
+
V
DC
–
2c
Filter
I
AC
V
AC
50 Hz
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