System Design Using Sungrow String Inverters

String inverters are becoming the most common style of inverter used with PV power systems ranging from 500kW to 20MW.  The goal of good system designers is to construct systems that maximize overall performance, while keeping the inverters operating within their design limits.  This paper is a very clear and easy explanation of the best ways to select string sizes as well as the optimum DC to AC ratios for the Sungrow string inverters.  Understanding the relationship between the string voltage, MPPT operations within the inverter, and how to take advantage of the 110% “overload” capacity will help maximize both system performance and the return on investment for systems that properly employ Sungrow string inverters.