Abstract
This thesis presents the development of an experimental micro-grid system using two insulated gate bipolar transistor (IGBT) modules. While a module is employed to construct a single-phase three-wire (1P3W) 220/110V inverter, the legs in another module are arranged to form the main source voltage boosting converter and the interfacing converters for various energy storage devices. First, the 400V common DC grid is established by a single-quadrant DC/DC boost converter from the main source, such as photovoltaic cell, fuel cell, or switched-reluctance generator. Then a supercapacitor bank and a battery bank are respectively interfaced to the common DC grid via its bi-directional DC/DC converter for making discharging and charging works. The simple robust control is applied to yield well-regulated and robust DC output voltages of all DC-DC converters. Finally, a followed 1P3W inverter is developed to yield 220V/110V AC outputs from the 400V DC grid. In schematic configuration, the outer two legs of an IGBT module are arranged to produce the 220V-voltage output, and the remaining center leg is in charge of switching control to yield two balanced 110V-voltage outputs. In control aspect, a master and a slave control schemes are proposed to respectively handle the 220V and 110V output waveform controls. The simple robust control approach is proposed to yield good inverter sinusoidal 110V/220V output waveforms under varied system parameters and unknown nonlinear loads. The system operation control of the developed micro-grid system is properly arranged. And the whole system operating performance is assessed experimentally.