rnating Current Overhead: Line Parameters, 61.1 Alternating Models, Standard Voltages, Insulators ine Line Parameters. Models- Standard Voltages.Insulators Mo-Shing Chen 61.2 Alternating Current Underground: Line Parameters, University of Texas at Arlington Models, Standard Voltages, Cables Cable Parameters.Models. Standard Voltages. CableStandards K.C. Lai 61.3 High-Voltage Direct-Current Transmission