Hi Diego

Filter directly gets input voltage oscillation. So you will have better DC wave to give it to DC DC converter to set up or down this voltage. Specially if your converter has no controller, it should have this filter to give pure DC wave for giving a qualified DC voltage at converter output.

Regards

Also about the value of the filter, it completely depends on PV array out put voltage. For example if your array produces maximum 100 VDC, you should select a capacitor with tolerability more than 100 VDC.

For stabilizing the input voltage to the DC-DC converter. Consequently, the changes in its duty cycle are reduced which increase its lifetime,and may reduce its operating temperature.

Adding to what Prof.Mohamed El-Shimy has mentioned..In general, the passive elements of DC-DC converter are designed considering "pure" or "constant" DC. Hence, it is essential to make sure that the source/supply to the DC-DC converter is pretty close to the "consideration". Adding a capacitor helps to meet the basic requirement of a constant or pure DC input voltage.

I also agree with the comment of Dr. Prabhakar. Such reasons and other reasons including the insufficient quality of materials and manufacturing processes are among the main causes of disappointing lifetime levels of most electronic subsystems. In addition, the designs for costs minimization sacrifice the desired/expected quality levels.

To suppress the fluctuations or ripple of the PV output we use a DC link capacitor as a filter element. The value of this capacitor can be found by observing/assuming the ripple in the PV output voltage. The addition of DC link capacitor gives smooth DC voltage for the DC-DC converter input and thus the requirement of frequent duty cycle changes get reduced.

To suppress and stabilize the PV output voltage. also DC converter parameters design are considered constant input voltage.

To eliminate ripple in voltage.

To stabilize the DC output voltage.

To have a pure Dc voltage.

Dear Researachers can any guide how to model this filter in matlab (simulink) .....

Thanq in advance