Defense Scheme on Java Bali 500 kV Transmission System Using Load Shedding by Voltage Bus Sensitivity

Voltage stability is important in maintaining an electric power system performance, especially in a network system with a large loading capacity and long transmission. As the disturbance or fault occurs in the power network, an analysis of the stability of the power system and the selection of load reduction is crucial to be made based on the sensitivity of the bus voltage. The Java-Bali system is very extensive and important to be analyzed to ensure whether the system will remain stable in the presence of disturbances after receiving backups from other distant power plant generators. The proposed method to find the sensitivity of the bus voltage is by calculating the ratio between the changes in voltage and the changes in reactive power taken from power flow results. After the disturbance in the north line, it is necessary to release the load at NEW UJBRG 1, NEW UJBRG2, SRLRU, and SRLYA with bus voltage sensitivity of 11.4, 11.4, 11.2, and 10.4, respectively. For faults on the south line, the discharge is carried out at NEW UJBRG 1 with a bus voltage sensitivity of -0.3. Meanwhile, during disturbances in the north and south lines, network normalization is carried out by trying to release the load at SRLRU, CWANG A, and BKASI A with bus voltage sensitivities of -0.2, -0.3, and -0.4, respectively. After removing the suggested load in certain buses, the system normally runs again.