Distribution Substation Automation using HMI

An electrical substation is an important part for the distribution of electric power. Due to non-linear behavior of electric power the magnitude of voltage and current keeps on changing. The change in the magnitudes causes different faults such as over current, over voltage, under current, under voltage. This faults can causes system unbalancing and damage the protective equipment. To overcome this problem various techniques are used up till now. In this project the PLC and HMI are used in the substation for the purpose of protection against the different faults. The PLC will work as a relay and will compare the values of voltage and current with the preset value and issue the signal to trip coil of contactor. The faults will be analyzed, corrected and the display of magnitudes of voltages, currents and fault acknowledgement will be done using HMI. The methodology used for fault detection and correction is distance protection. The monitoring of the single line diagram can be done with the help of HMI. Due to the large screen display of the HMI it can replace the numerical relay. With this the system reliability would increase.