PROJETO E CONTRUÇÃO DE UM RESTAURADOR DINÂMICO DE TENSÃO MAURICIO GALASSI ENGENHARIA ELETRICA UNIVERSIDADE DE SÃO PAULO BRASIL

PROJETO E CONTRUÇÃO DE UM RESTAURADOR DINÂMICO DE TENSÃO
MAURICIO GALASSI UNIVERSIDADE DE SÃO PAULO BRASIL
DISSERTAÇÃO APRESENTADA A ESCOLA POLITÉCNICA DA UNIVERSIDADE SÃO PAULO
PARA OBTENÇÃO DO TÍTULO DE MESTRE EM ENGENHARIA ELETRICA
LINK
http://www.mediafire.com/view/1w0e5s9n65c17xd/VERSAOFINALT-TESIS_DVR-BRASIL.pdf

Gate Drive Technologies Reinhard Herzer Semikron Elektronik GmbH& CoKG Nuremberg, Germany

LINK
http://www.mediafire.com/view/7ehvrk3olfeh8vf/S1_Documentation_Herzer.pdf

Non-isolated Single Phase Uninterruptible Power Supply (UPS) System Muhammad Aamir Department of Electronics, Electrical, Control, & Instrumentation Engineering Graduate School of Engineering Hanyang University South Korea

( Abstract ) In this thesis, a high performance single phase transformer-less online uninterruptible power supply (UPS) is proposed. The use of the bidirectional buck-boost converter with high conversion ratio not only reduces the number of batteries but also ensures a transformer-less system. The rectifier has capability of power factor correction and provides regulated DC link voltage whereas the inverter provides a regulated sinusoidal output voltage to the load. In order to control the transient effect, efficient control scheme is adopted in the system. The overall efficiency of the system is improved with significant reduction in size and weight of the system due to decrease number of batteries. Qualitative analysis and experimental results obtained with a 500VA prototype shows a normal efficiency of over 94% and an input power factor of over 99%.
LINK
http://www.mediafire.com/view/319sin33r9x19d5/Non-isolated_Single_Phase_Uninterruptible_Power_Supply_(UPS)_System.pdf

Filtering Methods for DC Link Voltage Control of Common-neutral-type Transformerless Single-phase UPS

Filtering Methods for DC Link Voltage Control of Common-neutral-type Transformerless Single-phase UPS UPS is largely divided into passive-standby, line-interactive, and double-conversion types. Commonly a double-conversion type is used at a site requiring a high reliability. These days, important factors of UPS are high efficiency, low input current distortion, high input power factor, small cabinet size and low price. In this thesis, a common-neutral type transformerless UPS is proposed. A proposed UPS is composed of PFC with 1-switch voltage doubler strategy, half-bridge inverter, separate battery charger and separate battery discharger. PFC with 1-switch voltage doubler strategy and half-bridge inverter are configured as commom-neutral type so that they can convert power without input and output transformer. Therefore input and output transformers can be removed, so the efficiency can be improved and cabinet size can be reduced. Also advantage of PFC with 1-switch voltage doubler strategy and half-bridge inverter is that they need a small number of switching devices so they can simplify driving circuitry and reduce the price. Advantage of separate battery charger and separate battery discharger is that they can make battery voltage lower than DC link voltage so they can reduce the quantity and cost of battery which is an important part of UPS. PI controller was used as voltage controller and current controller of PFC. In order to compensate imbalance of positive and negative DC link voltages, imbalance voltage PI controller was used. In order to compensate leading effect of input current, duty feedforward method was used. Several methods to eliminate 120Hz ripple component in DC voltage feedback were compared with each other. Moving Average resulted in better performance than other methods. Half-bridge was used as inverter circuit. In order to achieve stable static output voltage and improve dynamic characteristic multi-loop control method was used. Finally, the value of proposed UPS was confirmed in the method of simulation and experiment.
LINK
http://www.mediafire.com/view/2mdbwm62nnxca1r/TRANSFORMER_LESS_UPS.pdf

A study on Development of an algorithm for reducing neutral current in three-phase four-wire PWM rectifier of UPS Kim,SeungHo Dept. of Electrical Engineering Graduate School of Industry and Engineering Seoul National University of Science and Technology

LINK
http://www.mediafire.com/view/biy1liofkhrdmak/dq-based_individual_phase_control_of_three-phase_four-wire_PWM_rectifier_for_UPS.pdf