ABSTRACT Thisproject introduces a high-gain single-stage boosting inverter (SSBI) foralternative energy generation. As compared to the traditional two-stageapproach, the SSBI has a simpler topology and a lower component count. Onecycle control was employed to generate ac voltage output. This project presentstheoretical analysis, simulation and experimental results obtained from a 200 Wprototype.
The experimental results reveal that the proposed SSBI can achievehigh dc input voltage boosting, good dc–ac power decoupling, good quality of acoutput waveform, and good conversion efficiency.A single-phase grid connectedtransformerless photovoltaic (PV) inverter for residential application ispresented. The inverter is derived from a boost cascaded with buck converteralong with a line frequency unfolding circuit. Due to its novel operatingmodes, high efficiency can be achieved because there is only one switchoperating at high frequency at a time, and the converter allows the use ofpower MOSFET and ultra-fast reverse recovery diode. This dissertation beginswith theoretical analysis and modeling of this boost-buck converter basedinverter. And the model indicates small boost inductance will leads to increasethe resonant pole frequency and decrease the peak of Q, which help thesystem be controlled easier and more stable. Thus, interleaved multiple phasesstructure is proposed to have small equivalent inductance, meanwhile the ripplecan be decreased, and the inductor size can be reduced as well.
A two-phaseinterleaved inverter is then designed accordingly. Index Terms—Microinverter, one cycle control (OCC), tapped inductor (TI) 1. INTRODUCTION Energyis the basis of human life.
The past few decades, energy is the backbone oftechnology and economic development. In addition to men, machines and money,’energy’ is now the fourth factor of production. Without energy, no machinewill run, electricity is needed for everything. Hence, our energy requirementshave increased in the years following the industrial revolution. With theworsening of the world’s energy shortage and environmental pollution problems, protectingthe energy and the environment becomes the major problems for human beings.
Thus the development and application of clean renewable energy, such as solar, wind,fuel cell, tides and geothermal heat etc., are getting more and more attention.Among them, solar power will be dominant because of its availability andreliability.
As predicted by, the solar will provide the electricity up to 64%of the total energy by the end of this century as shown in Figure 1.1. Photovoltaic(PV) power generation has become one of the main ways to use solar energy. Andthe renewable energy source based distributed generation (DG) system arenormally interfaced to the grid through power electronic converters orinverters. Thus developing a photovoltaic grid-connected inverter system is importantfor the mitigation of energy and environmental issues.