Power cables serve a crucial role in connecting transmission and distribution utilities as a part of expansion in the electricity grid with the recent trend. The electric potential separation in cable applications (joints, bushings and terminations) is controlled by the electrical strength between the solid interfaces. The imperfections in the dielectric insulation caused by surface roughness and assembly inaccuracies at the onsite conditions lead to voids in the interfaces responsible for discharges. These cavities above a critical size could initiate a higher electron avalanche, causing a failure in the insulation at the interface. Our proposed controlled surface structuring of silicone insulation material in the micron range, based on a wrinkleformation process, introduces a controlled cavity volume between the insulation parts, which reduces the number of failuretriggered cavities and extends the interface length simultaneously. All these studies were conducted previously on flat substrates. To more accurately replicate real-world conditions, this work examines the field distribution on a cylindrical surface with a constant gap distance (10 mm) while varying the configuration of the external electrodes. Using COMSOL Multiphysics, theoretical simulations enable the development of an optimal design for investigating the interfacial discharge mechanism in a cylindrical module.