Balancing the load of 20 kV feeder using FACTS based on fuzzy control method

In electric power distribution networks, most of the times are single-phase and therefore their connection is between one of the phase wires and the neutral wire. In most cases, the number of branches on each of the phases does not feed the same subscribers, and in case of equality, their consumption is different due to different uses of single-phase consumers. Therefore, unlike balanced three-phase loads, in single-phase distribution systems, current flows through the neutral wire, and for this reason the distribution network is generally an unbalanced network. The imbalance of this system has various consequences such as reduced efficiency, performance of the protection system, increased losses, heating of three-phase equipment, voltage drop due to unbalanced current, neutral wire current and reduced power quality. Especially from the point of view of power quality criteria, this problem manifests itself as the ratio of zero sequence size to positive sequence outside the standard. In this paper, a method based on the use of FACTS devices and fuzzy control is described, which reduces the adverse effects of imbalance. In this method, the voltage imbalance index is within the allowable standard of distribution networks. The simulation results show that the stated control method reduces the effects of imbalance and the control method has established the objectives with appropriate speed and accuracy.