Voltage control in power system using expert system based on SCADA system

This paper presents the type of expert system for controlling the 22 kV voltage levels of a power system in the northern region of Thailand based on the SCADA system. At present, for the operation, the operators have to make decisions by their knowledge and experience to control the voltage. This expert system is obtained for alleviation of voltage violation in the day-to-day operation of a distribution substation in the system, and for processing the data from the SCADA for helping the operator detect buses experiencing abnormal conditions. This expert system focused on shunt reactive compensating devices and transformer tap change to select the most effective control for keeping the bus voltage in the entire system within limits. This study selected 6 distribution substations to be tested with this expert system. The performance of the expert system is compared with the operator control in the terms of voltage deviation indices, numbers of tap changing and minimizing losses.