About the book: he application of HVDC technology has received new impetus with the evacuation of large quantum of power from remote hydro and thermal stations. In addition, the controllability of power flows in the power grid has added a new dimension to the use of HVDC links in the context of developing Smart Grids. The power transfer from off-shore wind generation is another new application. DC transmission at distribution level voltages (using VSC-HVDC) is also being considered for integration of distributed generation in the power grid. This edition is a complete revision of the first edition taking into account the developments that have taken place since the first edition was published. In particular, the emerging technology of VSC-HVDC links is described in detail. Instead of adding new chapters to present the new developments, the new material is added at the appropriate places. For example, the analysis of VSC is presented in chapters 2 and 3 along with the thyristor based Line Commutated Converters (LCC). Practically, in all chapters, there is discussion of VSC-HVDC. The book also presents other developments such as the application of hybrid active filters, capacitor commutated converters, double and triple tuned filters etc. Chapter 10 presents power flow analysis in AC-DC systems based on a novel approach. The modeling, simulation and study of interactions among AC-DC systems is covered in the last 2 chapters without missing any relevant topics. The appendices give details of thyristor and IGBT valves, transient simulation of converters and DC lines, synchronous generator modeling, SSR analysis, CIGRE Benchmark models and design of DC and AC voltage controls in VSC-HVDC links. Several examples and case studies are included to illustrate the concepts. The book should be useful as text/reference to students, researchers and engineers from utilities/industries who wish to study and apply HVDC power transmission.