Abstract: The study describes a mathematical model of the Distribution Transformer Substation (DTS) created in MATLAB with using Simulink and SimPowerSystems libraries. Five typical DTS cells were identified with their schemes of main circuits and a list of items. An electrical scheme of model DTS was composed and Simulink model was built on this base. The power and data inputs and outputs in subsystems were considered, as well as disconnectors realization with main blades and earthing switches. Problems of disconnector blocking were discussed. The proposed model allows to analyze DTS operation modes considering measurement, signalization and control circuits of circuit breakers and disconnectors. A DTS operations modes and typical commutations in it were modelled.