With scarce the energy source and the worsened environment pollution, how to create and use a clean and never exhausted energy is becoming very important day by day. This thesis we proposed the research and development of a solar energy storage system with fuzzy logic control. This solar energy storage system is composed of the solar cell, charger, batteries, buck converter and digital a signal processor. The solar energy storage charging system charger is based on buck circuit control with battery cycle pulse charging. with the fuzzy control theory combined in the tactics of charging , it¡¦s can improve the efficiency of charging, suppress the abnormally battery temperature rise, lengthen the battery¡¦s life, and reduce the waste used. In the experiment, four different charging methods, with the same starting voltage, are compared in terms of temperature control. Among the four methods, the fuzzy logic control proposed in this thesis is able to control the battery temperature at a good 30 Celsius Degree. Experimental and simulation results demonstrate the effectiveness and validity of the system.

This thesis presents a Mixed Linear/Switching Control (MLSC) scheme for voltage regulator modules (VRM). The MLSC employs two loops of feedback compensation, inner-loop switching compensation and outer-loop linear regulation. The purpose of the switching compensation is to linearize and stabilize the buck converter under the influence of switching noise and load variation. With switching compensation, the linearized plant of the buck converter can be simplified to a first-order stable transfer function at low frequencies. Accordingly, the outer-loop linear controller can be easily designed to regulate the output voltage using the linear control theory. The advantage of the proposed MLSC scheme is two-fold: easy to design and of low circuit complexity. There is no need of using any current detecting resistor and PWM generator, and also the stability and performance can be easily met by choosing positive controller coefficients. A 12V/1V single-phase VRM with proposed control is designed and simulated, which shows an output regulation with 0.4% steady- state output error and 7% load regulation error in response to the load current steps from 60A/1A to 1A/60A, at a slew rate of 60A/µsec.

This thesis comprises two topics : the first one is the design and implementation of FlexRay automotive communication system physical layer. The second part is the design of a high efficiency DC/DC Buck converter with sub-3 ¡Ñ VDD. The first topic discloses the physical layer design comprising the Bus Guardian and the Bus Driver used in an in-vehicle network compliant with FlexRay standards. It is realized in a mixed-signal chip using TSMC 1P6M 0.18 £gm CMOS process. Its core area is less than 0.8 mm2, and power consumption is less than 60 mW. The second topic is to design a DC to DC step-down converter, which can accommodate wide range VDD. By utilizing stacked power MOSFETs, a voltage level converter, a detector and a controller, the design is realized by a typical 1P6M 0.18 £gm CMOS process without any high voltage technology. The core area is less than 0.184 mm2, while the VDD range is up to 5 V. Since the internal reference voltage is 1 V, it can increase the output regulation range. The proposed design attains very high conversion efficiency to prolong the life time of power supply. Therefore, it can be integrated in a system chip to provide multiple supply voltage sources.

In this thesis, the design of a Switching Power Supply for switched-reluctance motor drive system power factor correction is presented. Switching power technology for the power supply is now widely used, which has the main advantages of high efficiency and small size. However, the traditional type of Switching Power Supply will reduce the impact on electricity usage and quality, and produce electricity pollution and waste, for example low power factor, and high harmonic distortion. In order to improve the power factor, this paper used the traditional method of multiplier power factor correction circuit, and the use of state-space averaging method to analysis Buck Derived Converters to implement the Switching ¡@ Reluctance Motor Drive circuit design; In addition, this thesis used the Average Current Control method to cause the inductor current to follow a sinusoidal signal, achieving the purpose of¡@power factor correction.The design of Buck Converters is based on switching theory. With this method, the electricity pollution problems introduced by switching reluctance motor drives is solved by the Averagingmethod derived form the converters. The mathematical Buck Converter model is brought into a block diagram, based on the design of Buck¡@Converters, and then simulated with PsPICE software. Finally the design of the output voltage control, compensation and current control loop is performed.

Thesis (M.P.A.)--Kutztown University of Pennsylvania, 1996. / Source: Masters Abstracts International, Volume: 45-06, page: 2961. Typescript. Includes bibliographical references (leaf 93).

This thesis is an ongoing project of Ericsson with collaboration of Blekinge Institute of Technology [BTH], and Linneaus University [LNU] to compare the functionality and performance of three controllers Polynomial Pole Placement, PID [Proportional Integral Derivative] and PD controller in third order. This paper presents the state space modeling approach of DC-DC Buck converter. The main aim of this thesis is, by considering the buck converter system of Ericsson BMR450 with the PID, POLYNOMIAL and PD controllers at feedback loop, thus running their Matlab file with their appropiate Simulink block diagram, and comparing the three controllers performance by verifying their appropiate output graphs. The third order controller design is complicated and response is slow. The second order design is easy and gives better responses than third order Polynomial, PID and PD controllers. / As per the results point of view, the polynomial performed well than PID and PD controllers. The simulations show that the polynomial controller reaches the reference voltage very well, were the PID and PD result does not differ very much while meeting with the required reference voltage. Thus we conclude that the Polynomial controller design and results were better than the PID and PD Controllers. If we compare both the second order [4] and third order controller methods, The second order controllers are easy in design and gives better responses than third order polynomial PID and PD controllers. / ERCS.MADHU KIRAN, D.NO: 1/1/131, B.C.COLONY, MUTHUKUR, NELLORE, ANDHRA PRADESH, INDIA. PIN - 524344. THOTA. Partha Saradhi, C/O CH SUVARNA RAJU D.NO: 4-5-47, VEGIVARI CHAVADI, KOTHA PETA, WARD NO:21, KOVVUR, WEST GODAVARI,ANDHRA PRADESH, INDIA PIN - 534350,

Worldwide, renewable energy systems are booming with reliable distributed generation (DG) technologies to help fuel increasing global energy consumption and mitigate the corresponding environmental problems. High cost and low efficiency are major problems for such systems using traditional buck inverters with line-frequency transformers. This thesis has proposed a novel single-phase single-stage buck-boost inverter suitable for cost-effective small DG systems. The inverter was analyzed from the angle of energy exchange and transfer with two current control schemes, DCM and CCM. Sinusoidal PWM (SPWM) control method, based on DCM, was discussed in details with steady state analyses, computer simulations, and laboratory tests. A concise model with underlying equations was derived to represent the physical behavior of proposed inverter. Closed-loop SPWM control was simulated and verified to have fast dynamic response and good tracking performance with robustness and insensitivity to dc input fluctuations, ac grid variations, and component parametric uncertainties. Other control strategies were also investigated from the critical DCM, CCM, or energy approach to either increase the fundamental output or further improve the performance. Comparisons demonstrated that SPWM was preferred control method with low output THD, reduced switching losses, and simple implementation. Therefore, it is concluded the proposed inverter provides a low-cost and high-efficient solution for small DG systems with low component count, minimal dc and ac filtering requirements, and improved performance.

Thesis (Ph. D.)--Ohio State University, 2007. / Includes bibliographical references (p. 154-168). Also issued online.

abstract: Switching regulator has several advantages over linear regulator, but the drawback of switching regulator is ripple voltage on output. Previously people use LDO following a buck converter and multi-phase buck converter to reduce the output voltage ripple. However, these two solutions also have obvious drawbacks and limitations. In this thesis, a novel mixed signal adaptive ripple cancellation technique is presented. The idea is to generate an artificial ripple current with the same amplitude as inductor current ripple but opposite phase that has high linearity tracking behavior. To generate the artificial triangular current, duty cycle information and inductor current ripple amplitude information are needed. By sensing switching node SW, the duty cycle information can be obtained; by using feedback the amplitude of the artificial ripple current can be regulated. The artificial ripple current cancels out the inductor current, and results in a very low ripple output current flowing to load. In top level simulation, 19.3dB ripple rejection can be achieved. / Dissertation/Thesis / Masters Thesis Electrical Engineering 2016

Resumo: Este trabalho apresenta um novo conversor PWM CC-CC buck não isolado. O conversor é gerado a partir de uma célula de comutação de três estados, composta basicamente por dois interruptores ativos, dois passivos e dois indutores acoplados. Neste conversor apenas metade da potência da carga é processada pelos interruptores ativos, reduzindo assim a corrente de pico sobre estes à metade do valor da corrente de pico de saída, tornando-o importante para aplicações em potências mais elevadas. O volume dos elementos reativos (indutores e capacitores) é reduzido, pois, pela característica do conversor, a freqüência da ondulação da corrente e da tensão de saída é o dobro da freqüência de operação dos interruptores. Para uma menor freqüência de operação, diminuem-se as perdas na comutação. Devido à topologia do conversor, as perdas totais são distribuídas entre todos semicondutores, facilitando a dissipação de calor. Outra vantagem é possuir uma menor faixa de operação na região de descontinuidade em comparação com o conversor buck clássico, ou seja, a faixa de operação no modo de condução contínua é ampliada. É detalhada a abordagem através de análises qualitativa e quantitativa do emprego da célula de comutação de três estados no conversor buck, operando em toda faixa de variação da razão cíclica (0 .D .1). Além de toda a análise matemática e desenvolvimento através de simulação digital, um protótipo de 1kW foi implementado e testado em laboratório. Os principais resultados experimentais estão apresentados e discutidos neste trabalho. / Abstract: This work presents a new PWM DC-to-DC non-isolated buck converter. The converter is generated using the three-state switching cell, comprised of two active switches, two diodes and two coupled inductors. In this converter only part of the load energy is processed by the active switches, reducing the peak current in these switches to half of the value to the peak of the load current. This feature permits to operate this topology in larger power levels. The volume of the power reactive elements (inductors and capacitors) is also decreased since the ripple frequency on the output is twice the switching frequency. For a lower operating frequency, the switching losses are decreased. Due to the topology of the converter, the total losses are distributed among all semiconductors, facilitating the dissipation of heat. Another advantage of this converter is the smaller region to operate in discontinuous conduction mode when compared to conventional buck converter or, in other words, the operation range in continuous conduction mode is enlarged. The theoretical approach is detailed through qualitative and quantitative analyses of the employment of the three states switching cell in the buck converter, operating in the entire every variation range of the duty cycle (0 < D < 1). Besides the mathematical analysis and development through digital simulation, a prototype of 1kW was implemented and tested at laboratory. The main experimental results are introduced and discussed in this work. / Orientador: Falcondes José Mendes de Seixas / Coorientador: Grover Victor Torrico Bascopé / Banca: Dionízio Paschoareli Junior / Banca: João Onofre Pereira Pinto / Mestre