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This paper describes the application of finite elements for the modeling and simulation of overhead power-line structures in the high-frequency range, using existing computing tools and software. This paper treats specifically non-uniform wire arrangements common in overhead power networks, including line junctions, bends, neutral grounding, etc., which disturb the transmission of signals, especially at high frequencies, increasing reflections, radiation, and mode conversion. The proposed models could be used in applications associated with broadband communication over power lines providing a reliable representation for assessing the capability of the overhead network to carry high-frequency signals and estimate the resulting electromagnetic emissions. Index Terms--Broadband over power lines (BPL), electromagnetic (EM) emissions, finite elements, high-frequency line models.

This paper describes an integrated control and protection scheme for the power conditioner used by the medium rating grid-connected distributed generators and storage devices. The proposed control scheme consists of two loops: a steady-state loop that achieves optimum harmonic output by selective elimination of low-order harmonics and a transient loop based on space vector methods that enhances the transient response of the generator and provides overcurrent protection and fault rejection. The paper presents simulation studies of a grid-connected storage device equipped with a controller based on the proposed scheme. The results of these studies demonstrate the robustness of the controller to varying line conditions and disturbances. Index Terms--Distributed generation and storage, forced-commutated inverters, space vector control.

This paper presents a high-pulse shunt compensation scheme based on the 3-level GTO-inverter which requires minimal magnetic interface. The scheme utilizes small inductors, rather than phase-shifting transformers, for combining several 3-level inverters to a high-pulse static synchronous compensator. The resulting arrangement has an output harmonic profile comparable to a 48-pulse inverter. A suitable control scheme is developed for the proposed compensator which provides smooth var control for the network. Simulation studies are presented in the paper, which demonstrate that the proposed design could decrease the complexity of advanced compensation schemes. Keywords: STATCOM, three-level GTO-inverters, FACTS, Harmonic elimination, Phase-shifting transformer.

The paper presents an advanced scheme for the shunt compensation of the distribution system that can significantly improve the harmonic profile of the line without increasing the system complexity and size. The scheme employs a transformerless arrangement of 3-level GTO inverters that can generate a 5-level output. A gate control is developed that fully utilizes the capabilities of this arrangement to provide a 12-pulse operation for the compensator. The proposed compensator can connect directly to the distribution grid without a transformer. The effectiveness and performance of the proposed compensator are tested through simulated studies on a 13.8 kV distribution system. Key words: Static Synchronous Compensator, three-level GTO-inverters, Harmonic elimination.

This paper addresses the problem of controlling and modulating the power flow of long transmission lines using a series-connected Solid-State Synchronous Voltage Source (SVS). The design of the various control functions of the SVS is presented along with EMTP simulation studies. The results from these studies demonstrate the effectiveness of the proposed approach in regulating the line power and, also, in providing power modulation that can enhance the dynamic and transient performance of the line. Key words: Power flow control, Line loadability, Solid-State Synchronous Voltage Source.