## 1 Introduction  
Escalating urbanization and industrialization has resulted in an increased load demand along with the necessity of higher system stability and reliability, which requires the upgrade and new installation of power transmission schemes (PTSs) [1; 2; 3; 4; 5]. Moreover, renewable energy integration [6; 7], smart grid development [5; 8], and the need of interruption-free operation in the case of faults [8; 9] also require the implementation of PTSs within metropolitan areas [10; 11]. Researchers have described that conventional PTSs include overhead lines (OHLs) [1; 3; 5; 10; 12], underground cables (UGCs) [7; 13; 14] and gas-insulated lines (GILs) [15; 16; 17; 18]. Literature regarding the metropolitan application of PTSs mentionedthat OHLs and UGCs encounter hindrances such as right of way [2; 3; 19], spatial proximity [9; 20; 21], aesthetics [19; 20], system failure due to prolonged fault clearance time [8; 9], corrosion [2; 22], trench requirements [14; 23], and electromagnetic compatibility (EMC) concerns [2; 4; 21; 24; 25]. Further, studies mentioned that conventional GILs also face impediments regarding their implementation in urban vicinities due to their metallic profile, such as their structural rigidity [15; 25; 26], larger bending radius and lay length [15; 16; 27], jointing complexities [15; 17; 27], corrosion protection [16; 24; 28], requirement of acceleration dampers [17; 24; 29], and trench development [11; 27; 30]. Thus, protruding urbanization, despite being a potential load consumer, critically curtails the implementation of conventional PTSs in metropolitan vicinities. References [11; 31; 32; 33; 34] reveal that flexible gas-insulated lines (FGILs) comprised of a reinforced thermoplastic enclosure, stranded conductor, and polyurethane (PU) post insulator are a potential candidate for curtailing the intricacies associated with the implementation of conventional PTSs in metropolitan areas. Further, researchers [35; 36; 37] have mentioned that flexible cables and enclosures like FGILs are practicable for horizontal directional drilling (HDD)-based underground laying schemes and do not require trench development, which is highly beneficial in urban vicinities. Thus, the simplification of several issues associated with conventional PTSs like right of way, EMC concerns, trench requirement, corrosion protection, and larger land area requirement makes FGILs an appropriate scheme for the subsurface metropolitan application of high-voltage lines. However, researchers have mentioned that the contour irregularity of stranded conductors [38] is a point of concern due to its irregular field distribution [39; 40], which results in poor field utilization [17; 24; 41; 42] and augments partial discharge activity [43; 44; 45] and streamers [43; 45; 46]. Moreover, references [17; 24; 41; 42] mentioned that the interdependence of enclosure and conductor sizes apropos of field utilization necessitate critical consideration regarding the dimensional specifications of FGILs in case of any variation in their field utilization. Thus, field irregularity due to stranded conductors in FGILs along with its effect upon dimensional specification needs thoughtful consideration. Researchers [47; 48; 49; 50; 51; 52; 53; 54; 55; 56] mentioned that regarding GILs, irregular field distribution and partial discharge activity due to electrode irregularities could be curtailed by the implementation of a solid dielectric layer on the electrode. However, the implementation of a solid dielectric layer in an FGIL would result in its reduced structural flexibility, which is objectionable regarding their metropolitan applications. A probable solution for conductor irregularity suppression in FGILs could be the implementation of a flexible semiconducting film (SCF) over the stranded conductor. SCFs basically exhibit non-linear conducting characteristics and will facilitate the minimization of the field irregularity and field intensity of FGILs without compromising their structural flexibility.