Modelling and Control of Modular DC-Nanogrids Based on Loss-Free Resistors

• Main Authors: Reham Haroun, Abdelali El Aroudi, Angel Cid-Pastor, Enric Vidal-Idiarte, Hugo Valderrama-Blavi, Luis Martinez-Salamero
• Format: Article
• Language: English
• Published: IEEE 2020-01-01
• Series: IEEE Access
• Subjects: Loss-free resistor (LFR); dc-nanogrid (dc-NG); sliding mode control (SMC); bidirectional converter (BDC)
• Online Access: https://ieeexplore.ieee.org/document/8999600/
• ISSN: 2169-3536

This paper proposes a modular photovoltaic (PV) dc-Nanogrid (dc-NG) architecture for residential applications. The proposed architecture is based on the Loss-Free Resistor (LFR) concept. The dc distribution bus is supplied by PV panels, ac utility and a storage battery. The storage battery is connected to the main dc bus through a dc-dc bidirectional converter (BDC). This battery has also an important role to ensure uninterruptible power supply to the critical loads and controls the power flow in the dc-NG. A mathematical model of the system is first derived and a stability analysis is carried out showing that the stability is guaranteed under certain mild conditions. Numerical simulations of a case study for two PV panels corroborate the theoretical predictions which have been finally confirmed by experimental measurements.