Modeling of Step-up Grid-Connected Photovoltaic Systems for Control Purposes

Energies

Adriana Trejos²  Daniel Gonzalez¹ 

[1] Universidad Nacional de Colombia, Medellin 05001000, Colombia; E-Mails:;Instituto Tecnologico Metropolitano, Medellin 05001000, Colombia

关键词: photovoltaic system;    control systems;    non-minimum phase analysis;    modeling;    grid-connected;   

DOI  :  10.3390/en5061900

来源: mdpi

【 摘 要 】

This paper presents modeling approaches for step-up grid-connected photovoltaic systems intended to provide analytical tools for control design. The first approach is based on a voltage source representation of the bulk capacitor interacting with the grid-connected inverter, which is a common model for large DC buses and closed-loop inverters. The second approach considers the inverter of a double-stage PV system as a Norton equivalent, which is widely accepted for open-loop inverters. In addition, the paper considers both ideal and realistic models for the DC/DC converter that interacts with the PV module, providing four mathematical models to cover a wide range of applications. The models are expressed in state space representation to simplify its use in analysis and control design, and also to be easily implemented in simulation software, e.g., Matlab. The PV system was analyzed to demonstrate the non-minimum phase condition for all the models, which is an important aspect to select the control technique. Moreover, the system observability and controllability were studied to define design criteria. Finally, the analytical results are illustrated by means of detailed simulations, and the paper results are validated in an experimental test bench.

【 授权许可】

CC BY   
© 2012 by the authors; licensee MDPI, Basel, Switzerland.