AN3105

Input current harmonics measurement

Doc ID 16774 Rev 2

9/30

3

Input current harmonics measurement

One of the main purposes of a PFC pre-conditioner is the correction of input current

distortion, decreasing the harmonic contents below the limits of the relevant regulations.

Therefore, this demonstration board has been tested according to the European standard

EN61000-3-2 Class-C relevant to lighting equipment, at full load and nominal input voltage

mains. Measurement results are in Figure 4 - on the lefthand side.

The circuit shows its ability to reduce the harmonics, also well below the limits of

EN61000-3-2 Class-C regulation, not only at full load but also at significant lower load; on

the righthand side of Figure 4 the input current harmonics measurement at light load

(minimum input power to be compliant with the above mentioned rule is 25 W) shows that

even if the power supply is working out of its typical operating region it is still compliant with

the EN61000-3-2 Class-C limits.

Figure 4.

EVL130W-SL-EU demonstration board: compliance to EN61000-3-2 Class-C standard

THD = 6.85%, PF = 0.981

THD = 10.3%, PF = 0.753