D2-01-28 Role of ICT in Power Sector Presented by Shri. Kishor Chavan & Rakesh Guhagarkar Deputy Director(Technical), Maharashtra Electricity Regulatory Commission, Mumbai
Agenda • Role of ICT in Power Sector • Challenges in Transmission • WAMS / PMU • Real Time Application of WAMS • WAMS implementation in Maharashtra, India. • Regulatory Support
From Traditional to Future Grid Future Grid Traditional Grid • Decentralized and distributed power generation • • Intermittent renewable power generation • • Consumers become also producers (CPP) • • Multi-directional power flow (Inter Regional) • Short Term Open Access Transactions are increasing • • Operation based more on real-time data • Centralized power generation • • One-directional power flow • • Generation follows load • • Operation based on historical experience • • Limited grid accessibility for new producers
Role of ICT in Power Sector • Information and Communication Technologies has a major role to play:- • By allowing two way communication throughout the grid, • Not only power but information is also transported, • Numerous intelligent devices are continuously interacting with each other
Role of ICT in Power Sector • Major Applications of ICT in Power Sector:- • Automatic Meter Reading • Remote Disconnect and Reconnect • Demand Side Management and Load Management • Integration of Renewable Energy • Integration of Distributed Generation, standby, mini grids and off-grid • generation • Demand response • Advanced Metering Infrastructure (AMI) • Wide Area Measurement System (WAMS) • Phase Measurement Unit (PMU)
General Challenges in Transmission Networks • Increasing demand for power • Transmission networks get bigger by aggregation (island interconnected) • Distance between generation and load changes • Laws, regulations & politics often impede building power plants where they are needed • Introduction of distributed energy resources e.g. wind, Solar • Load flow becomes volatile • Modern supervision and smarter tools to manage the increasing complexity of the grid are needed; • Increase the utilization of new technologies e.g. WAMS • to allow the networks to operate closer to its capacity • while maintaining system security
Wide Area Management System • Conventional system:- • Analog and digital information related to the power system, such as circuit breaker status, frequency, voltage and power flow (MW/MVAr) measured at substation level and is presented in the LDC through SCADA/EMS . • The information is routed and updated every 10 seconds at respective LDCs. • Limitations of SCADA:- • Angular separation between coherent group of generators within a synchronous grid is representative of the grid stress. The measurement of angular separation and its telemetry at the control centre level in SCADA / EMS has limitations. • The load angle is either estimated from the available SCADA data or the angular separation between pair of substations is derived offline with the help of power flow on the line, impedance of the line and respective voltage. • Both these methods have limitations due to data latency and inaccuracies inherent in SCADA/EMS.
Wide Area Management System PMU PMU PMU PMU PMU PMU PMU • WAMS is an ICT application which has overcome the limitations of SCADA. • With WAMS, it is possible • To monitor the phase angles at the control centre. • To visualize magnitude and angle of each phase of the three phase voltage/current , frequency, rate of change of frequency and angular frequency at every few milliseconds interval (say 40 ms) in the LDCs. • To observe transient / dynamic behavior of the system in near real time at the control centers. PMU PMU
Phase Measurement Unit • The Phasor Measurement Unit (PMU) is the basic building block of WAMS. • PMU definition (as stated in IEEE Std.C37.118-2011): • “A device that produces synchronized measurements of phasor(i.e. its amplitude and phase), frequency,ROCOF (Rate of Change Of Frequency) from voltage and/or current signals based on a common time source that typically is the one provided by the Global Positioning System UTC-GPS.” • PMU measures the system state viz. voltage and angle of a particular location at a rate of multiple samples per second. This data is time stamped through a common reference and transmitted to the Phase Data Concentrator (PDC) installed at a nodal point, through high speed communication medium.
Phase Measurement Unit Phasor represents magnitude and phase angle at any given instant of sine wave of voltage or current PMU typical configuration
Wide Area Monitoring (WAMS) : Real time Application • Phase Angle Monitoring • Voltage Stability Monitoring • Power Oscillation Monitoring
WAMS Application : Phase Angle Monitoring Benefits: Provide operator with real time information about voltage phase angle deviation, Improve voltage control, improve system stability, security and reliability , and operate safety carrying components closer to their limit.
WAMS Application : Voltage Stability Monitoring Normal Operation Early warning Emergency alarm Benefit: Early warning against voltage collapses, Immediate stop of cascading effects, and Protection against uprising voltage instabilities.
WAMS Application : Power Oscillation Monitoring System Status: Normal, Warning and Alarm WAMS Benefit: Detection of oscillation, Assessment of power system damping, Increase power transfer at defined security, and Early warning to avoid power system collapse.
Benefit of Using PMU • Real time monitoring • Post-disturbance analysis • Adaptive protection to avoid cascading outage • Power system restoration • Improve calculation for real time path flow and optimal dispatch • Provide actual limits of the system instead of the conservative ones from offline calculations • Improved backup protection • Reduce chance of recurrence of system outage Source: Dr. Luigi Vanfretti, KTH Sweden
Special Report Question Q.1 How is ICT utilized in Maharashtra, India, for implementing WAMS? What is the percentage of grid observable using such systems? Any challenges in implementation?
PMU Implementation in India • In India, fourteen (14) Phasor Measurement Units (PMUs) have been commissioned as on 31st May 2012. In the Northern Region, the PMUs have been placed at nine 400 kV substations viz. Vindhyachal (HVDC back-to-back station), Kanpur (with SVC), Dadri (HVDC inverter terminal), Moga, Kishenpur, Agra, Bassi, Hisar and KarchamWangtoo. • In Western Region PMUs have been placed at two 400 kV substations viz. Raipur and Bhadravati. In Southern Region, they have been placed at three 400 kV substations viz. Salem, Hyderabad and Bengaluru. • The three Phasor Data Concentrators (PDC) have been installed at the respective Regional Load Despatch Centres (RLDCs) located in New Delhi, Mumbai and Bengaluru. Placement of PMUs/PDCs at few more locations in India has been envisaged under the pilot projects taken up by the RLDCs. • After completion of all the pilot projects, there would be 53 PMUs and 6 PDCs in India.
WAMS implementation in Maharashtra by MSETCL WIDE AREA MEASUREMENT SYSTEMS (WAMS)- To enhance Operation, Monitoring capability and observability of GRID • WAMS SCOPE • PMU Locations: 15 (400kV stations and some 220kV stations) • GPS Locations :15 • At SLDC-Kalwa- • Phasor Data Concentrator(PDC), • Visualisation software, • Archiving software and Historian server • Situational Awareness • Commissioned on Aug- 2012, installation of Situational Awareness is in progress. PMUs : 15 Locations PDC at SLDC Kalwa Situational Awareness
Challenges in Implementation of WAMS • Scale of Project: implement a full fledged project or first we should go for a pilot project and then scale it up to a full project. • Selection of PMU Locations: • Reasonably far off nodes to get a wider footprint. • close to large generating complex • Availability of fast communication from the PMU location. • 3. Reliability of synchrophasor data: • Data loss occurs due to communication problem between PMU and control center. • 4. data retrieval from the historian: • Retrieval of data from historian is possible only for duration of 3 minutes. Hence retrieval of longer duration data is quite time consuming. • 5. Analysis of synchrophasor data • Microsoft excel is being used for plotting and analyzing of synchrophasor data. There is limitation with excel that only 35000 data points can be plotted. Hence better plotting techniques needs to be explored for plotting of data for larger duration.
Q.2 Please give your future plans on how would envision the grid operations with WAMS and necessary regulatory support requirements. Ans. Future Plan:Phase-1: Placement of 1186 nos. PMUs at all lines in HVDC terminal stations, 400kV & above voltage level S/s, generating station stepped up at 220kV level & above where Fibre Optic(FO) cable along with communication equipment is either existing or being implemented by 2014-15.Placement of Nodal PDC (27 nos) at strategic sub-station, Master PDC(25nos) at SLDCs, Super PDC (5) at RLDCs, 2 No PDC at Main & BackupNLDC, Remote console at each RPC(5) , UT(3) ,Sikkim , NTMC(2),CEA(1) & NER States(4) ,Total 16 . Phase-2: Placement of balance 483 nos. PMUs at all HVDC terminal stations, 400kV & above voltage level S/s, generating station stepped up at 220kV level & above along with provision of Fibre Optic connectivity and communication equipments.
FIBRE OPTIC COMMUNICATION NETWORK WITH PMU LOCATION IN WESTERN REGION –Phase-I ( 83 PMU)
Regulatory Support Requirement To provide certainty and confidence to utilities, investors and technology providers for making necessary investment Regulatory support is required across 3 key dimensions: