Basics of SCADA, and its component Remote Terminal Units etc

This presentation just started with Types of Measurement System and SCADA Basics

1. EE21405 Wide area monitoring system (WAMS) Prepared by: Dr. Vishal Kumar Gaur Lecture 02

2. Remote Measurement Systems Our traditional system or many current electric grid was designed and built decades ago using system design models and organizational principles that must be now restructured to meet the needs of a low-carbon and digital economy. The traditional architecture was based on large-scale generation remotely located from consumers, hierarchical control structures with minimal feedback, limited energy storage, and passive loads . This traditional system was not designed to meet many emerging trends. 2

3. 1965 Great North east blackout (USA & Canada) The blackout was caused by reaching an erroneously set threshold value and lack of monitoring of the power network performance. Consequently, Supervisory Control and Data Acquisition (SCADA) Systems were emerged! Affected States: New York, Connecticut, Massachusetts, Rhode Island, small segments of northern Pennsylvania and northeastern New Jersey, and substantial areas of Ontario, Canada Total load loss: ~20,000 MW 📅 Date & Time: November 9, 1965 | 5:16 PM (EST ) ⛔ Affected Population: ~30 million 🕒 Duration: up to 13 hours 3

4. 1965 Great North east blackout (USA & Canada) The major causal factors were as follows: A backup protective relay operated to open one of five 230-kV lines when the loading on the line exceeded the 375-MW relay setting instead of the expected 700 MW.. Operating personnel were not aware of the operating set point of this relay When the flows redistributed instantaneously on the remaining four lines, they tripped out successively in a total of 2.5 seconds. The resultant power swings resulted in a cascading outage that blacked out much of the Northeast. Without real-time monitoring, operators had no visibility or control to stop the cascading failures. 4

5. 1965 Great North east blackout (USA & Canada) Post- Blackout Recommendations (FPC & NERC) The Federal Power Commission (FPC) , later succeeded by FERC , conducted an investigation. Urged development of : Automated remote telemetry Supervisory control capabilities Real-time state estimation and alarms Birth of SCADA in the 1970s Utilities began adopting RTUs (Remote Terminal Units) to collect data from substations. SCADA systems were installed to: Monitor voltages, currents, power flows Automate switching Perform basic state estimation 5

6. SCADA Evolution Post-1965 6 Year Milestone 1965 Blackout triggered realization of system-wide control gaps 1970s Deployment of first-generation SCADA in control centers 1980s Integration of energy management systems (EMS) with SCADA 2000s Limitations of SCADA recognized → shift to WAMS 2010s+ PMUs and synchrophasor -based real-time systems adopted

7. SCADA SCADA stands for Supervisory Control and Data Acquisition. It is a computer-based system used in power systems (generation, transmission, and distribution) to monitor, control, and analyze the operation of electrical equipment from a centralized control room. Functions Data Acquisitions Remote Monitoring Remote Control Data Storage & Analysis Event and Alarm Management 7

8. SCADA Components of a SCADA System: Field Devices RTUs Communication Network Master Station Human-Machine Interface (HMI) 8

9. Remote Measurement Systems: SCADA 9 9 State Estimation RTU RTU RTU Supervisory Control & Data Acquisition System Noise Error and Uncertainty Missed State estimation is used to get best estimates of the voltage magnitude and angle form set of measurements received from field

10. Thanks ! 10 Faculty: Dr . Vishal Kumar Gaur