Analysis of Induced Voltage of Optical Fiber Composite Ground Wire in 35 kV Overhead Distribution Lines

Considering the significantly increasing development of the optical fiber composite ground wire (OPGW) on 35 kV overhead line systems, especially for constructing new power systems in Chinese provinces with intense lightning storms, this article studies the power-frequency induced voltage on the OPGW with segmented insulation and midpoint grounding conditions, which have not been of concern and well addressed on the 35 kV distribution lines before. Three types of towers recommended by standard design files are investigated for numerical simulation via the EMTP/ATP platform using the multitransmission line model. The influence of the line parameters and operation conditions on the induced voltage is investigated. It is found that the amplitude of induced voltage on the OPGW shows a "V-shaped" distribution along the line and is proportional to the load current of the phase conductors, while the induced current can be significantly eliminated. The induced voltage of steel towers is the smallest among the concrete poles, steel towers, and steel tube poles, determined by the relative spatial position of the OPGW and phase lines. Tower height, conductor transposition, ground-wire dc resistance, and single-circuit phase sequence do not affect the induced voltage. For double-circuit lines, there is a nine times difference in induced voltage amplitude between the same-phase sequence and reverse sequence conditions.