Recently, an increasing number of asymmetric consumers have been connected to the transmission network, with increasing power differences in individual phases. This leads to the appearance of voltage asymmetry, one of the most important indicators of electricity quality. Voltage asymmetry is mostly affected by asymmetric load. Single-phase electric traction plants (EVP) for the transmission network represent the largest source of asymmetry. They are connected via single-phase transformers in which the primers are connected between two phases. They generate inverse system currents into the network, which cause additional heating of the iron in the generator, especially in the rotor. Voltage asymmetry causes a rise in load current and losses od voltage, power and energy in the network. The permissible values are defined by the standards EN 50160 and IEC 61000. Among newer solutions for asymmetric load balancing, the imbalance compensator is mentioned, whose working principle is described in the penultimate chapter. In this work, the modeling od three-phase substitution schemes of basic network elements is presented, since a three-phase calculation is used to determine asymmetric conditions. Also, the Newton-Raphson method is described, one of the most commonly used methods for calculating power flows under asymmetric conditions. It is distinguished by a small number of iterations since the convergence of the procedure is not affected by a significant increase in the number of nodes. In the key part of the thesis, using the ETAP software package, network opportunities were analyzed through several variants. The area is covered by a part of the Croatian transmission network from Zagreb to Rijeka and a part of Slovenia. The obtained results are mostly in accordance with the stated norms and recommendations. As a conclusion of the simulation, the assumption that the propagation of the inverse voltage component decreases with distance from the EVP connection point was confirmed.