TThe inTeresT in phasor measuremenT Technology has reached a peak in recent years, as the need for the best estimate of the power system's state is recognized to be a crucial element in improving its performance and its resilience in the face of catastrophic failures. in most countries installing the phasor measurement units (pmus) and getting to know the pmu system behavior through continuous observations of system events has been the first step. all installations are reaching for a hierarchical wide-area measurement system (Wams) so that the measurements obtained from various substations on the system can be collected at central locations from which various monitoring, protection, and control applications can be developed. in this article, experts from several countries summarize their Wams-related activities in some detail. it is of course not possible to claim that this is a complete list of countries pursuing this technology. To the best of our knowledge similar activities are also progressing in south africa, Taiwan, Japan, and several other countries. however, the contributions here provide an account of the most advanced stages in Wams development in major world economies.-A.G. Phadke The Brazilian national interconnect power system (sin) is characterized with a dominant hydroelectric power generation and long-distance power transfers from generation parks to load centers (Figure 1). studies for phasor measurement applications in Brazil were started in the early 1990s by the study committee of the interconnected operation coordination group (gcoi), prior to the deregulation of the Brazil energy sector. difficulties faced by the Brazilian economy during that decade and the restructuring process of the electric energy sector delayed the project.

We study the effect of overlapping resonances on the angular distributions of the reaction F+H2(v=0,j=0)-->HF(v=2,j=0)+H in the collision energy range from 5 to 65 meV, i.e., under the reaction barrier. Reactive scattering calculations were performed using the hyperquantization algorithm on the potential energy surface of Stark and Werner [J. Chem. Phys. 104, 6515 (1996)]. The positions of the Regge and complex energy poles are obtained by Pade reconstruction of the scattering matrix element. The Sturmian theory is invoked to relate the Regge and complex energy terms. For two interacting resonances, a two-sheet Riemann surface is contracted and inverted. The semiclassical complex angular momentum analysis is used to decompose the scattering amplitude into the direct and resonance contributions.

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Topologically stable nontrivial spin structures, such as skyrmions and antiskyrmions, display a large topological Hall effect owing to their quantized topological charge. Here, we present the finding of a large topological Hall effect beyond room temperature in the tetragonal phase of a Mn-Ni-Ga based ferrimagnetic Heusler shape memory alloy system. The origin of the field induced topological phase, which is also evidenced by the appearance of dips in the ac-susceptibility measurements, is attributed to the presence of magnetic antiskyrmions driven by D 2d symmetry of the inverse Heusler tetragonal phase. Detailed micromagnetic simulations asserts that the antiskyrmionic phase is stabilized as a result of interplay among inhomogeneous Dzyaloshinskii-Moriya interaction, the Heisenberg exchange, and the magnetic anisotropy energy. The robustness of the present result is demonstrated by stabilizing the antiskyrmion hosting tetragonal phase up to a temperature as high as 550 K by marginally varying the chemical composition, thereby driving us a step closer to the realization of ferrimagnetic antiskyrmion based racetrack memory.

Consistent high growth of Indian economy has resulted in a surging demand for energy. Since, independence Indian power system has grown from 1362 MW to 250GW. In the past decade, installation of renewable sources of energy for electricity has grown at an annual rate of 25%, which has reached 29,500 MW as on March 2014. Despite this, presently 400 million people in the country have no access to electricity and hundreds of millions get electricity for only a few hours. Distribution system is suffering from frequent and long duration outages. To supplement capacity addition as well as electrification of remote areas, development of micro-grid also needs attention. Standalone/decentralized micro grid can provide basic energy access to all.Presently, high AT&C losses of utilities are resulting into poor financial health of distribution utilities across the country. To address these issues and bring efficiency, seamless integration of emerging technologies in the field of monitoring, automation, control, communication and IT systems with active participation of all stakeholders are inevitable. It is expected that the far-reaching goals of modern Indian power system can be achieved by deployment of smart grids which can help to improve efficiency of Indian power sector. In this direction, several initiatives have been taken to implement smart grid in entire supply value chain -generation, transmission distribution and consumer participation in power sector. This paper presents initiatives taken by Power Grid Corporation of India Ltd. (POWERGRID) to implement Smart Grid in Indian Power System as a case study on Puducherry Smart Grid Pilot Project.

The quantum of power that a given EHVAC transmission line can safely carry depends on various limits. These limits can be categorized into two types viz. thermal and Stability/SIL limits. In case of long lines the capacity is limited by its SIL level only which is much below its thermal capacity due to large inductance. Decrease in line inductance and surge impedance shall increase the SIL and transmission capacity. This paper presents a mathematical model of increasing the SIL level towards thermal limit. Sensitivity of SIL on various configuration of sub-conductors in a bundle, bundle spacing, tower structure, spacing of phase conductors etc. is analyzed and presented. Various issues that need attention for application of High Surge Impedance Loading (HSIL) Line are also deliberated.

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