A new method for the design of a bidirectional inverter based on the sinusoidal pulse-width modulation principle and the use of a low-cost and lightweight ferrite-core transformer is presented. The inverter is designed for either ohmic or inductive loads. In the case of inductive loads the reactive power is transferred back to the DC input power source using a new active rectifier design. The inverter is controlled by two minimum-time feedback loops, providing relatively low output voltage distortion (less than 2% for DC input higher than 24V) and good load regulation (better than 2%), while the inverter efficiency remains relatively constant (from 80 to 85%) over a wide output power range (75 to 200W) and DC input voltage range (23 to 28V). Theoretical results are experimentally verified using a laboratory prototype.

http://www.idea2ic.com/Rectifierless%20AC%3C-%3EDC/Bridgeless/AC2DC/A%20bidirectional,%20sinusoidal,%20high-frequency%20inverter.pdf

A bidirectional, sinusoidal, high-frequency inverter design

The series chopper type power train for EV is proposed for aiming the increase of one battery charge driving range. A motor-test bench and also actual car were constructed, and the proposed power train with SAZZ (Snubber Assisted Zero voltage and Zero current Transition) chopper was experimentally compared between with and without the chopper.

Experimental data analysis on total driving performance of series chopper based ev power train

This paper deals with high input voltage LED driver with a requirement of power factor correction (PFC). A series-connected metal-oxide-semiconductor field-effect transistors (MOSFETs) circuit which can support high total blocking voltage is proposed. Compared with the existing series-connected devices methods, this circuit can efficiently and reliably operate in a wide voltage range situation. Thus it can be applied in low cost flyback-based single-stage PFC ac/dc converter. In this circuit, the main switch is directly driven by the control IC while the slave switch is driven by an auxiliary circuit. The auxiliary circuit can also realize effective voltage sharing. The turn-on and turn-off operation principle is analyzed in detail. Then voltage stresses of the devices are derived, and the power losses of the auxiliary circuit are calculated, meanwhile a method of decreasing the voltage stress and power losses is given. Design guidelines are also provided in this paper. Experimental results basic on a 75W prototype show the proposed circuit works well with a 480Vac input.

High input voltage single-stage flyback AC/DC LED driver using series-connected MOSFETs

Improving A.C. Regulator Input Power Factor by Multiplexed Asymetrical Phase-Control

This book is primarily intended to be a textbook on protection, suitable for final year undergraduate students wishing to specialize in the field of electric power engineering. It is assumed that the student is familiar with techniques of power system analysis, such as three-phase systems, symmetrical components, short-circuit calculations, load flow, and transients in power systems. The reader is also assumed to be familiar with calculus, matrix algebra, and Laplace and Fourier transforms and Fourier series. Typically, this is the background of a student who is taking power option courses at a U.S. university. The book is also suitable for a first year graduate course in power system engineering. An important part of the book is the large number of examples and problems included in each chapter. Some of the problems are decidedly difficult. However, no problems are unrealistic, and, difficult or not, the aim is always to educate the reader, help the student realize that many o f the problems that will be faced in practice will require careful analysis, consideration, and some approximations. The book is not a reference book, although it may be of interest to practicing relay engineers as well. The book offers derivations of several important results, which are normally taken for granted in many relaying textbooks. By studying the theory behind these results, students may gain an insight

B.M. Bird

Papers

Introduction to Power Electronics [Books and Reports]