Design, Modeling And Simulation Of Substation For Energy Management Using Plc Based Scada System:

Abstract

Energy Management System (EMS) and Supervisory Control and Data Acquisition (SCADA) are a strongly linked and associated with each other. SCADA system combines power data and process data (both analogue and digital) to enable a real-time analysis of the impact of process changes and energy consumption. In distribution systems certain measures are taken for supervision, control, operation, measurement and protection and highly onerous works that take lot of man power. So the need of advanced automatic control system to reach the required destination becoming mandatory, to supersede antiquated ways that are persisting in the present destination system. This thesis emphasizes mainly on the SCADA (Supervisory Control and Date Acquisition) system, the most sophisticated automatic control system, being used in distribution for quality of power. The SCADA systems remote terminal unit (RTU or PLC) will be installed in switching substation (15KV) which will constantly monitor electrical parameters (Pf, P, Q, V, I and F) and send the data to MTU (Master Terminal Unit). Power which is fed to Adama substation comes from two main sources, from Koka hydro Electric power station and Adama wind farm 1 wind station. Despite the existence of these sources there is always power interruption problems in the distribution substation. This is due to the antiquated ways of distribution network and the lack of automatic monitoring and controlling systems in the substation. The research result depicts the reliability of Adama substation does not meet the requirements set by IEEE standards. The system average interruption frequency index (SAIFI) of the substation is 312.0614 interruptions per customer per year with system average interruption duration index (SAIDI) of 428.8393 hours per customer per year at the base case. Based on the research result, the application of PLC based SCADA system on each feeder lines or switching substations, resulted in the improvement of SAFI by 65.31% and SAIDI by 66.26%. The simulation result also shows that this system increases the performance of the distribution substation by using SCAD/EMS to monitor and control the operation of the field devices so as to achieve data acquisition, device control, parameter adjustment, measurement and various signal alarms.