AN3180

List of figures

Doc ID 17273 Rev 1

3/39

List of figures

Figure 1.

EVL6563S-200ZRC 200W PFC demonstration board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Figure 2.

Some basic topologies with zero-ripple current characteristics . . . . . . . . . . . . . . . . . . . . . . 4

Figure 3.

Smoothing transformer and related currents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Figure 4.

Coupled inductor a = k ne model under zero-ripple current conditions. . . . . . . . . . . . . . . . . 6

Figure 5.

Figure 6.

Coupled inductor a = n model under zero-ripple current conditions . . . . . . . . . . . . . . . . . . . 8

Figure 7.

Ripple-current attenuation as a function of the error sources for various winding coupling 12

Figure 8.

Examples of high-leakage magnetic structures (cross-section) . . . . . . . . . . . . . . . . . . . . . 13

Figure 9.

Two-section slotted bobbin suggested for the realization of a coupled inductor - top view 14

Figure 10.

Two-section slotted bobbin suggested for the realization of a coupled inductor - side view14

Figure 11.

Partial ripple cancellation: still under compensated . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Figure 12.

Partial ripple cancellation: overcompensated . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Figure 13.

200 W PFC pre-regulator with ripple-free input current: electrical schematic. . . . . . . . . . . 20

Figure 14.

Harmonic emissions and conformity to JEITA-MITI standards . . . . . . . . . . . . . . . . . . . . . . 23

Figure 15.

Harmonic emissions and conformity to EN61000-3-2 standards . . . . . . . . . . . . . . . . . . . . 23

Figure 16.

200W PFC pre-regulator with ripple-free input current: typical performance . . . . . . . . . . . 24

Figure 17.

Line current and voltage @ full load (200 W) - Line current and voltage @ 115 Vac -

200 W . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Figure 18.

Line current and voltage @ full load (200 W) - Line current and voltage @ 230 Vac -

200 W . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Figure 19.

AC and DC winding currents nominal input voltages and full load (200 W) - AC and DC

winding currents @ 115 Vac - 200 W . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Figure 20.

AC and DC winding currents nominal input voltages and full load (200 W) - AC and DC

winding currents @ 230 Vac - 200 W . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Figure 21.

Conducted EMI @ Vin = 110 Vac, Pout = 100 W. Limits: EN50022 class B -

precompliance EMI test @ 115 Vac - 200 W . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Figure 22.

Conducted EMI @ Vin = 110 Vac, Pout = 100 W. Limits: EN50022 class B -

precompliance EMI test @ 230 Vac - 200 W . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Figure 23.

Coupled inductors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Figure 24.

Electrical equivalent circuit of coupled inductors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Figure 25.

Model of coupled inductors with a = n (a=n model) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Figure 26.

Figure 27.

Model of coupled inductors with a = 1 (a =1 model, or T-model) . . . . . . . . . . . . . . . . . . . . 33

Figure 28.

Model of coupled inductors with a = k ne (a = k ne model). . . . . . . . . . . . . . . . . . . . . . . . . 34

Figure 29.

Figure 30.

Winding connections: aiding flux (left), opposing flux (right). . . . . . . . . . . . . . . . . . . . . . . . 37