how to reduce ripple

these are the current and voltage values of sepic converter( standalone).

these are the same current and voltages of sepic when connected to the input of grid connected inverter. how can reduce these ripples?

Answer 1

[Sahas]

Hi,

As per my understanding, you are plotting the output voltages and current of a SEPIC converter when it operates independently and when it is connected to a grid-tied inverter. In the second case, the current and voltage plot shows ripples at the start and then their values get saturated.

I used a standalone SEPIC converter found at the MathWorks File Exchange forum to reproduce the graphs. I was able to reproduce the ripple free current and volage graphs.

To reduce the voltage and current plots of the SEPIC converter with a grid-ties inverter, try out the following steps:

• Increase the capacitance at the input and output of the SEPIC converter as it acts as a low-pass filter which helps smoothening voltage ripples.
• Adding more inductors in series at the input of the SEPIC converter help in filtering out current ripples.
• Operating the converter at a higher “switching frequency” may reduce the ripples amplitude.

Refer to the following MathWorks documentation links below for more information on modelling a “Grid-Tied Inverter” and the SEPIC converter:

• https://www.mathworks.com/discovery/grid-tied-inverter.html
• https://www.mathworks.com/matlabcentral/fileexchange/91670-sepic-converter

Hope this helps in reducing the ripples!