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The distribution and interleaving (D&I) of signals is a common method for ripple attenuation in various engineering applications in such areas as control, communication, and power electronics. Similarities to this technique may also been found in nonengineering fields such as biology and medicine. This paper presents a mathematical exploration of distributed interleaved systems along with a simple frequency-domain model of interleaving. We are hoping that the insights provided by this mathematical framework and the newly proposed model for interleaved systems will lead to enhanced techniques for evaluating D&I processes, and facilitate the design of better systems. In particular, we hope this work results in new approaches to low-pass filtering that will exhibit fast dynamics and very efficient ripple attenuation (in theory, this can produce complete ripple removal in some cases). Index Terms--Averaging, distributed system, dynamics, electromagnetic interference (EMI), interleaving, pulsewidth modulation (PWM), ripple, switched-mode power converter.

This paper presents an algorithm for the selection of corrective control actions for bus voltage and generator reactive power in a power system. A genetic algorithm (GA) using linear approximation of load flow equations and a heuristic selection of participating controls were combined in a search method for the minimum number of control actions. The method was successfully applied on a 220-bus model for several cases of disturbed load flow, and calculation time was proven to be small enough to allow real-time application of the algorithm. The GA was compared with a integer programming-based solution method and showed a considerably reduced calculation time. Index Terms--Genetic algorithm (GA), reactive power control, voltage control.

Realization of a loss-free resistor element (i.e., element with resistive input characteristic and yet loss-free) by means of switched mode converters operated in discontinuous current conduction mode (DCM) is presented. Practically, the input characteristic is not pure resistive due to the ripple and filtering effects. A method which enables reduction of the ripple to negligible values and the elimination of the input filter is presented, which facilitates realization of practical circuits with nearly pure input resistive characteristic. This approach is based on the operation of a group of converters operating in power sharing interleaved made. Index Terms--Active power factor, gyrator, loss-free resistor (LFR), low harmonics rectifier, time variable transformer (TVT), two-port power conservative, unity power factor.

A novel approach for pulsed power generation is described, in which conventional storage components are replaced by transmission line segments. Taking advantage of the propagation modes in transmission lines and making use of the fact that the time of appearance of a voltage pulse traveling on a channel is directly proportional to the electrical length of the channel, it is possible to synchronize power pulses in such manner to generate pulsed power. An multiple transmission line topology (MTLT) containing m transmission line segments is used. The difference in the electrical length from one line to the other should be T/m, where T denotes the period of the cycle. The resulting, output peak power is m times higher than the input peak power, due to either a rise in voltage, in current, or a combination of both. The current\voltage magnification would be defined by the choice of a suitable connection mode at the end points of the topology. The main advantages of the transmission line based topology are: a) the switching elements the system consists of need to withstand a much lower power than the power experienced by the load; b) the system can operate either at extremely high frequencies or with very short rise and decay times of rectangular pulses. This novel approach to energy compression is supported by simulation examples and experimentally validated. Index Terms--MTLT, power converters, topology, voltage magnification.

A new family of low-ripple dc-to-dc switching converters based on a parallel connection of N-identical boost converters with current-mode control (CMC) is presented. The CMC strategy ensures that all the converters operate at the same duty cycle, sharing an equal amount of input current and forcing the output voltage to be an integer multiple (N) of the input voltage. As a result, the total input current and output voltage ripples are extremely low. The generation of control signals from inductor currents feedback without using external triangular of sawtooth signals is another remarkable characteristic of the new converters family. Index Terms: Boost dc-to-dc switching converter, current-mode control, interleaving, low ripple, voltage multiplier.

A new approach to efficient gyrator realization is described. The approach was motivated by the observation that a [Lambda]/4 segment of transmission line exhibits gyrator-like behavior. A gyrator that operates at low-frequency band, including dc, is formed by the combination of a [Lambda]/4 segment of transmission line and a switching network. Using a switching bridge, the low-frequency signal is converted into a high-frequency wave which is applied to the input terminals of the transmission line. Then the original waveform is reconstructed using a second switching bridge. Since the switching bridge, as well as the transmission line, are loss free (in principle), the resulting gyrator is also lossless. Such a gyrator can find applications in power processing circuits. A circuit based on this approach was constructed and tested at the energy conversion laboratory, Tel-Aviv University, Israel. Index Terms - Distributed line topology, gyrator, high-frequency converter.

Presents a study which focuses on the transmission-line-based gyrator as it pertains to electrical circuit analysis. Presentation of a gyrator design based on the natural properties of transmission lines; Methods and materials used in the study; Details on experimental results.