Under the action of a strong electric field, conducting droplets suspended in a dielectric liquid deform, attract each other, and can merge after their touching. The latter processes are called electrodeformation and electrocoalescence. The arbitrary Lagrangian-Eulerian method is one of the available approaches to simulate two-phase media, which has one crucial advantage over other techniques: it lets describing step-change in liquid properties when crossing the interface between two fluids. However, it generally fails to simulate volume merging or separation (i.e., changing topology). Suggested here is a computational model, where the idea of how-to-describe topology change during electrocoalescence is implemented. The model was developed for one of the most complex problems when electrical conductivities of contacting phases differ by many orders of magnitude. Numerical results were experimentally verified, which enables the model application to describe electrohydrodynamic processes in two-phase immiscible liquids and, in particular, electrocoalescence.