Distributed Converters in Large PV Plants: Performance Analysis Supported by Behavioral Models

This paper is aimed to assess the performance of distributed converters in large PV plants through the analysis of a case study represented by a 2 MW PV plant in Central Italy. The electrical layout of a 500 kW subfield has been modified performing the installation of DC/DC converters at string level in order to create an independent MPPT control for every string. This kind of performance analysis is usually carried out using data acquired by the plant data logger. Unfortunately, the presence of partial unavailability, monitoring system faults, shutdown for maintenance activities, etc. can create several issues in data processing. To support data elaboration, a novel behavioral modeling approach has been developed and exploited in this work. This novel approach, based on an integrated state-space average model, can improve the performance analysis ensuring a satisfactory accuracy but keeping a low computation effort. Validation is performed considering real operating scenarios in case study.