1. Input filter design for CPM controlled converters
Reference paper:
Y.Jang, R.W.Erickson, "Physical origins of input filter oscillations in current programmed converters," IEEE Transactions on Power Electronics, Vol.7, No.5, Oct.1992.

7. Physical origins of input-filter oscillations
Design objective: Gvc should not be affected by the input filter:
Effects of input filter on Gvd
Effects of input filter on Gid
Additional “feed-forward” loop though vg

8. Effects of input filter on Gvd

11. Effects of input filter on Gid

12. Additional loop through vg

13. Additional loop through vg

14. Computation of Ggd

15. Effects of Ggd

16. Design criteria
Design objective: Gvc should not be affected by the input filter:
Effects of input filter on Gvd
Effects of input filter on Gid
Additional “feed-forward” loop though vg

17. Typical buck converter impedance criteria (see the reference paper)

18. Experimental example (see the reference paper)

19. Input filter oscillations: ZN and ZD
L=2.5mH
Ma=3 M2
D=0.35
R=10

20. Input filter oscillations: ZNf
L=0.275mH
Ma=0
D=0.47
R=25
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