A novel pulse-width modulated (PWM) single-phase line-interactive uninterruptible power supply (UPS) based on the small dc bus capacitor is presented. The proposed system is made up of an ac chopper which includes a diode rectifier, a boost switch, a charger and an inverter. It has the features of a small dc bus capacitor, small input and output inductors, and low switching loss, and is very su...

An Isolated ZVS/ZCS bidirectional DC-DC converter for DC Uninterruptable Power supplies is presented in this paper. The usual way to avoid a computer shutdown during the mains failure is to connect an ac uninterruptible power supply (UPS). Alternatively, in this paper, a simple and high efficiency dc UPS is presented by an isolated bidirectional soft-switching dc-dc converter. The bidirectional...

Uninterruptible power supplies (UPS) play an important role in interfacing critical loads such as computers, communication systems, medical/life support system and industrial controls to the utility power grid. They are designed to provide clean and continuous power to the load under essentially any normal or abnormal utility power condition. Among the various UPS topologies such as online UPS,...

The paper contains analysis of power factor correction circuits that is made in the context of elaboration of uninterruptable power supply system. Various correctors have been estimated analytically, by means of simulation and experimentally. The most significant attention has been paid to the efficiency of the analyzed converters and their compatibility with modular approach to development of ...

Auxiliary power supply (APS) systems are increasingly used for low power rating home appliances (e.g. televisions, water dispensers, etc.) and lighting (e.g. CFL lamps) in countries where long power rationing schemes are applied. In general, these systems charge a 240AH (Ampers-Hours) bank of batteries as long as the grid is on and then convert the stored energy into AC current to supply a load...

The distributed energy sources are commonly used small energy generating sources. Combination of these small energy sources will form microgrid in an interrelated manner to provide a required amount of demand power management. A grid connected PV system consist of solar panels, batteries with back up in case of emergencies, DC-DC converters, Maximum power point tracker (MPPT) and Demand power m...

A solar-wind hybrid power generation system has been presented here. The application based system illustrated in this paper is designed on the basis of the solar and wind data for areas in Northern India. The power generated by the system is intended for domestic use. The most common source of unconventional power in homes is battery based UPS (Uninterrupted power supply) inverter. The UPS inve...

Uninterruptible power supplies (UPSs) are emergency power sources which have wide spread application in critical equipments, such as computers, automated process controllers, and hospital instruments. With the rapid growth in the use of high-efficiency power converters, more and more electrical loads are nonlinear and generate harmonics. It is a big challenge for a UPS to maintain a high-qualit...

In this paper, the Renewable energy sources, which have been expected to be a promising alternative energy source, can bring new challenges when it is connected to the power grid. However, the generated power from wind energy source is always fluctuating due to environmental condition. In the same way wind power injection into the electrical grid affects the power quality due to the fluctuation...