The work solves the problem of assessing the operation modes of the Integrated Power System (IPS) of Ukraine taking into account the power flows increase to the states borders for integration into the ENTSO-E power system. The Transmission System Development Plan for 2021-2030 is considered, in which the construction of southern transit power lines is planned. The issue of the redistribution of power flows in the electric network with the possibility of transferring power from the eastern regions of Ukraine to the western ones is considered. The analysis of the optimal increase in the connection cross-section into ENTSO-E networks by introducing southern transit. The purpose of the work is to analyze and evaluate the introduction of southern transit power lines by a high voltage direct current network based on voltage source converters in the electric network of the Ukraine power system. This problem was solved with creating a model of an electric network of 750 and 330 kV of the Ukraine IPS, analyzing the simulation results and comparing the network operation modes when introducing southern transit by an alternating and direct current. The most significant results of the work are the proof of the technical feasibility of introducing southern transit on direct current with the ability to influence the capacities flow distribution. Significance of the obtained results consists in the development of the Ukraine IPS model with the direct current lines introduction, which allows to analyze the electric network operating modes while introduction of southern transit by direct current.