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CHAPTER 8: FILTER REALIZATION AND EXPERIMENTAL RESULTS
I [dBµA]
80
60
40
20
0
−20
−40
0.1 1 10
Frequency [MHz]
w/o filter
With filter
Limit
Figure 8.11: Comparison of Measured output DM emissions: without and with output
I [dBµA]
80
70
60
50
40
30
20
10
0
−10
EMI filter (115V-400Hz to 80V-100Hz)
−20
0.1 1 10
Frequency [MHz]
w/o filter
With filter
Limit
Figure 8.12: Comparison of Measured input CM emissions: without and with output
I [dBµA]
80
70
60
50
40
30
20
10
0
−10
EMI filter (115V-400Hz to 80V-50Hz)
−20
0.1 1 10
Frequency [MHz]
w/o filter
With filter
Limit
Figure 8.13: Comparison of Measured input CM emissions: without and with output
EMI filter (115V-400Hz to 80V-100Hz)
As it can be seen in the first two figures 8.10 and 8.11 regarding the DM emissions, they
now are clearly under the standards limit; it may seem a case of over-design for the
filter because it could attenuate at least 10dB less. However, as it has been explained
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