Modified Optimal Reliability Indices Calculation for Radial Distribution System

The basic function of an electric power system is to provide a reliable source of electricity to connected loads, and electricity is one of the major driving forces of economic growth. An Intermittent and unreliable power supply can hinder economic growth and may also result to loss of investment. Thus, it is vital for electric distribution utilities to serve its customer with the utmost reliable power supply. Most common measurement of reliability of distribution utilities is through the use of reliability indices such as System Average Interruption Frequency Index (SAIFI), and System Average Interruption Duration Index (SAIDI). The addition of protective devices in the electric distribution system has great impact in the overall performance of the system but this requires a substantial investment. In this paper, a modification of the equations in solving reliability indices is proposed to help a decision-maker determine the optimal location and type of devices to be installed in the distribution system. The effectiveness of the proposed modified equations is demonstrated in the test case.