Power Adaptor Device for Domestic DC Microgrids Based on Commercial MPPT Inverters

Abstract

This work presents a power adaptor device, referred as Smart Panel Device, allowing the connection of additional energy sources and storage elements to a domestic PV grid-connected system. The adaptor output port is designed to behave as a power source/sink, thus enabling its hot-swap parallel connection to renewable power sources without modifying their Maximum Power Point. Moreover, the adaptor device features a power characteristic with a single controllable MPP and allows the control of the injected power within the operating range of the DC-AC grid-connected inverter. The work presents the design principles of such device by describing the operation of a sliding-mode controlled quadratic boost converter. The proper operation of the device is experimentally verified for several scenarios in a small PV-based microgrid system including a fuel cell stack, a 1 kW three-phase wind turbine, a battery charger-discharger and commercial grid-connected PV inverters.

Dual Mode-Multiple Output SEPIC Converter Integrated with Passive Ripple Cancelling Circuit for Standalone PV Energy Harvesting System

“…Then, substituting Equation (4) and Equation (5) into Equation (3), P PV,r (t) and P PV,f (t) can be derived as follows: (6) where,…”

“…solar energy [4] [5] [6] [7]. However, the output voltages of each PV panel and back-up battery cell are quite low; hence arise the need of high step-up and high-efficiency converters to upgrade the low voltage [8] [9] [10].…”

A generalized design method for multifunction converters used in a photovoltaic system

“…The amount of power actively injected into the main grid from the PVG is determined by the PV-DC source block output voltage and current. The MPPT control circuit is an important part of the PV-DC source; its objective is to set up the PV arrays output reference voltage corresponding to the PV maximum power [3][4][5]. The inputs of the MPPT controller are the output voltage and current of the PV-DC source block.…”

Complementary Power Control of the Bipolar-type Low Voltage DC Distribution System

“…Various operation modes using a grid-connected converter and an energy storage device for a dc microgrid are described in [8]. The dc central supervisory controller with enabled communication interfaces is introduced in [9]. In [10], a dc system management scheme using EVs as the ESS for electric charge saving is described.…”