Performance Index Analysis (PIA) for N-1 Contingency Transmission in 150 kV Electricity System

Power system security is an important part of the electricity system. An electrical system should be able to detect or analyze the disturbance that occurs. The interference that occurs in the power system is divided into several faults with the generator, transmission, and load. The N-1 transmission contingency is a disturbance caused by outage of one transmission element in the electrical system. One of the analytical methods used for power system security is the Performance Index method. Performance Index Analysis (PIA) is a method used to rank contingencies when one transmission element is independent of the electrical system. Performance Index Analysis helps the engineer to determine the next step that will taken when an N-1 contingency transmission interference occurs in the system. In this study, Newton Raphson method is used to define a load flow in the electrical system. Based on the results of the Performance Index Analysis, it can be known that the load flow calculations using the Newton Raphson method can be used to determine the value of the Performance Index Power and Performance Index Voltage when there is a contingency disturbance. The N-1 contingency transmission scenario 8 is a contingency which has the highest index value in the 150 kV Malang Raya Electricity System. The highest performance index value in this study is 1.614. This index value indicate danger situation in the 150 V Malang Raya electricity systems. Infinite bus voltage has overvoltage of 317.75 kV. It happens because the L8 line dropped, then the active power that should flow towards the L5 line cannot delivered, so the voltage on the Infinite bus side increases. The G. Wlingi Bus, G. Sutami Bus, Kebon Agung Bus, Lawang Bus, Pakis Bus, Sengkaling Bus, Sutami Bus and Wlingi Bus also experience voltage changes of an average of 57% of the voltage under normal condition.