Generation of high voltage (HVAC & HVDC), high transient voltage. High voltage measurement. Electric strength of isolation materials. Electric field in homogeneous and heterogeneous materials. Graphical and experimental determination of electric fields. Phenomena of electric discharge forms, the gas discharge. Fluid isolation materials. Solid isolation materials. Extra high voltage long transmission lines, technical characteristics, equivalent circuit, voltage distribution along the line, real and reactive power flow along the line, methods of increasing the maximum power transferred along the line, of EHV DC transmission lines, rectification, inversion, equivalent circuit, analysis of operating conditions.