Monitoring and Utilization of SVC/STATCOM using SCADA/WAMS in Indian Power system

Abstract

Indian power system is one of the largest synchronous interconnections in the world. The installed capacity of more than 390 GW caters to the daily energy requirement of more than 1.38 billion people of India. The widespread transmission network of more than 448 thousand circuit kilometers experience conditions of high and low voltages. In such a large power system, variation is generally observed across various nodes of the system. The variation in voltage is both diurnal as well as seasonal in nature. During real time system operations, sometimes it becomes very difficult to maintain the system voltages as per the grid standards. The Indian power system has also experienced two major grid disturbances on 30-07-2012 and 31-07-2012. One of the cause of disturbances was voltage instability. After this disturbance, system planners suggested to install Flexible AC Transmission Systems (FACTS) at strategic locations to avoid recurrence of such disturbances in future. FACTS help in better controllability of the system and also improves the power transfer capability of existing transmission system which enhances reliability and security of the system. Indian power system has various FACTS devices in operation across various locations in the grid. The FACTS devices in India comprise of SVC, STATCOM, FSC and TCSC. To ensure better monitoring of the FACTS devices, phasor measurement units (PMU) are being installed at the terminals of FACTS devices. This paper has discussed the performance of SVC and STATCOM during the steady state and dynamic state. After the performance assessment, the system operator can provide the most suitable settings of these devices. The control settings are adopted based on historical data and existing system conditions. The regular feedback helps in optimum utilization as well as better performance of FACTS devices. The assessment of SVC and STATCOM is done using the data made available at control centers by SCADA and Wide Area Measurement Systems (WAMS).