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CHAPTER 8: FILTER REALIZATION AND EXPERIMENTAL RESULTS
I [dBµA]
100
80
60
40
20
0
−20
0.1 1 10
Frequency [MHz]
w/o filter
With filter
Limit
Figure 8.9: Comparison of Measured input CM emissions: without and with output
8.3.2 Output emissions
EMI filter (240V-50Hz to 168V-100Hz)
This section will now illustrate the impact of the designed filter on the output emis-
sions. At first the EMI in the case of an aircraft supply system are reported, showing
DM emissions (Fig. 8.10 and Fig. 8.11) and CM emissions (Fig. 8.12 and Fig. 8.13) for
50Hz and 100Hz output respectively. In all these cases, experimental measurements
demonstrate that the emissions have now droped under the limit.
I [dBµA]
80
60
40
20
0
−20
−40
0.1 1 10
Frequency [MHz]
w/o filter
With filter
Limit
Figure 8.10: Comparison of Measured output DM emissions: without and with output
EMI filter (115V-400Hz to 80V-50Hz)
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