Abstract
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.
Highlights
Future power grids will no longer be dominated by coalfired power stations
The ac-dc converter and the output of the cascaded boost Loss-Free Resistor (LFR) in each branch have been represented by constant power sources, Pf provided by the utility and Ppv delivered by the PV generators
Note that when the required power by the load is equal to 300 W, the input power is enough to supply the load and the extra generated power is used to charge the battery through the bidirectional converter (BDC) which operates in the buck-mode
Summary
Future power grids will no longer be dominated by coalfired power stations. The production of electrical energy will be based on distributed generation sources such as solar photovoltaic (PV) arrays, wind turbines and batteries forming nano and micro grids [1], [2]. The novelty of this work is the use of a LFR-based design for three different purposes, each of them corresponding respectively to each of the three basic blocks of the proposed nanogrid; namely, photovoltaic energy processing, ac utility connection, and bidirectional operation of the battery. Devices [35], [36], our proposal uses a single battery due to the low power handled by the nanogrid This storage battery is connected to the main 380 V dc bus using a BDC operating as an LFR with an additional outer voltage loop for regulating the dc bus. Note that the control variables u1,m u2,m appear in the expressions of the s1,m and s2,m through the derivative of the inductor currents iL1,m and iL2,m guaranteeing the sliding-mode operation of each stage in the different branches
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
