Analysis of induced components in hybrid HVAC/HVDC transmission lines on the same tower for various fault conditions.

• Accurate modeling of HPOTL considering electromagnetic coupling between AC and DC lines. • Simulating all types of faults in HPOTLs, including AC, DC and inter-system faults. • Complete investigation of induced components in AC and DC transmission lines in HPOTLs in different fault conditions with different fault resistances and locations. • Investigating the possibility of the impact of faults in one of the transmission lines (AC or DC) on the adjacent line protection system. • Investigating the most severe AC, DC and inter-system faults from the point of view of induction of voltage and current components in the adjacent line. The use of Hybrid Parallel HVAC/HVDC Overhead Transmission Lines (HPOTL) on the same tower can improve the power transfer capacity and transmission line stability and reduce power transient swing, but it will also present some challenges. The most important one is the electromagnetic coupling between the HVAC and HVDC lines due to the proximity of the lines. The electromagnetic coupling phenomenon induces different voltage and current components in the lines for different conditions, including the fundamental frequency component in the DC line and the zero sequence component in the AC line. The magnitude of the induced components is much higher in fault conditions than in normal conditions. The electromagnetic coupling between the HVDC and HVAC lines has a significant influence on their equipment and protection systems. In this paper, the induced components in the normal and various fault conditions in HPOTL are investigated with the detailed modeling of the HPOTL. In addition, the effect of faulty phase(s) or pole(s) for AC, DC, and AC/DC intersystem faults, fault location, and fault resistance on the induced component in transmission lines are investigated. Simulation results show that the electromagnetic coupling can cause the mal-operation of the protection system in healthy lines. [ABSTRACT FROM AUTHOR]