abstract

• A control design for an HB-NPC transformerless inverter is presented in this paper, the proposal includes a modified LCL passive output filter which is aimed to attenuate leakage-ground currents in a transformerless photovoltaic generation system. This modification consists of a simple connection of the filter capacitors to the positive and negative nodes of the DC-link. A theoretical analysis of the differential-mode and common-mode models is performed. Thus, the proposed control law is designed in these new variables of the system. Therefore, the proposed control law consists of two main loops, an inner control loop which is based on the differential-mode model, and a DC-link voltage balance control loop based on the common-mode model. The current tracking loop features a proportional gain plus a bank of resonant filters to enhance the tracking on the differential-mode current reference. The common-mode voltage loop features a PI controller aimed to guarantee the DC-link common-mode voltage regulation objective. To assess the performance of the proposed solution a 1 kW experimental setup of the H-bridge neutral-point clamped transformerless inverter is used with the proposed LCL filter and controller.

authors

• Escobar G.
• Iturriaga-Medina S.
• Langarica Córdoba Diego
• Lopez-Sarabia J.
• Martínez Rodríguez Pánfilo Raymundo
• Vazquez-Guzman G.

publication date

• 2023-01-01

published in

• International Journal of Electrical Power & Energy Systems  Journal

keywords

Digital Object Identifier (DOI)

• 10.1016/j.ijepes.2022.108724

PubMed ID

start page

end page

volume

• 146

issue