Hello everyone.
Can someone help with the calculation of Vout and Vin for Solar magic dc-dc converters? I am working on a design case where I have 10x 200W PV panels (Vmpp=26.3V), each to be equipped with SM3320 buck-boost (see reference design document SNOSB84C). Assuming I want to use a 200W converter (Pconv = 200W).
If every PV panel is Ppv=200W, Pstring = 2000W. With a dc_link voltage Vdc=400V, then the string current Istr=2000/400=5A. So far so good, the output voltage of each converter is Vout=(Pconv/Pstring)*Vdc=40V. Now, with these values in hand, if i calculate the buck mode duty ratio Dbk as per the formula reported in SNOSB84C Dbk=Vout/Vmpp=40/26.3=1.52. A duty ratio greater than 1 results, which sounds like that I am making a mistake somewhere along the lines.
Do you know with what Vout voltage the duty ratios should be calculated? If anyone has a feedback to give if would be greatly appreciated.
Thank you very much
