ERCOT Control Center experience in using Real-Time Contingency Analysis in the new Nodal market

Garcia, Freddy; Sarma, N.D.R.; Kanduri, V.; Nissankala, G.; Gopinath, K.; Polusani, J.; Mortensen, Tim; Flores, Iván

doi:10.1109/pesgm.2012.6345557

Cited by 16 publications

(5 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The report recommended that utilities should have a security assessment tool in the control centre that is capable of periodically assessing the system security for selected key contingencies [50]. This tool is commonly known as Real-Time Contingency Analysis (RTCA) and is now part of the EMS used in most utilities [51][52][53][54].…”

Section: Situational Awareness and Security Assessments In Power Systmentioning

confidence: 99%

Development of an Equivalent Circuit of a Large Power System for Real-Time Security Assessment

Wijeweera

Annakkage

Zhang

et al. 2018

IEEE Trans. Power Syst.

View full text Add to dashboard Cite

More and more system operators are interested in calculating transfer capability in realtime using real-time power flow models generated from the Energy Management System (EMS). However, compared to off-line study models, EMS models usually cover only a limited portion of the interconnected system. In most situations, it is not practical to extend the EMS model to capture the impact of the external systems and therefore using an equivalent network becomes necessary.The development of equivalent circuits to represent external areas was a topic discussed over the last 50 years. Almost all of these methods require impedance information about the external area to develop the equivalent circuit. Unfortunately utilities do not have the external impedance information in the real-time. Therefore, normal industry practice is to use off-line studies to develop an equivalent circuit and use that circuit in the real-time operation without any validation. This can result in errors in the security assessment. Therefore, power industry need a method to develop or validate an equivalent circuit based on the available real-time information. This thesis work is focussed on meeting that industry need.The work on this thesis presents two new methods that can be used to generate an equivalent circuit based on the boundary conditions. This method involves calculating equivalent impedance between two areas based on the boundary stations voltages, voltage angles and power leaving the boundary stations into external areas.This thesis uses power system simulation between two areas to change the system condition to obtain different boundary bus voltages, voltage angles and power injections to generate necessary data. Regression analysis and least square method is then used to generate the equivalent circuit using these data. It is expected that system changes will provide necessary information in the real-time to generate the equivalent circuit.The proposed methodology is validated with modified three area 300 bus system as well as using Manitoba Hydro's system. Contingency analysis, transfer level calculation and PV curves analysis is used to validate the proposed method. Simulation results show that the proposed method produces adequate accuracy in comparison with detailed off-line system models.The main advantage of the proposed method as compared to other existing methods such as Ward and REI is that the proposed method does not require external impedance information to generate the equivalent circuit. The ability to generate reasonably good equivalent circuit only using available boundary information will help utilities to generate or validate the equivalent circuit based on the current system conditions, which will intern help improve the accuracy of the security assessment.i Acknowledgments I would like to express my appreciation and sincere thanks to Udaya Annakkage, my research advisor, for his guidance, support and advice throughout this research. I was truly enriched by the many discussions we had over the course of thi...

show abstract

Section: Situational Awareness and Security Assessments In Power Systmentioning

confidence: 99%

Development of an Equivalent Circuit of a Large Power System for Real-Time Security Assessment

Wijeweera

Annakkage

Zhang

et al. 2018

IEEE Trans. Power Syst.

View full text Add to dashboard Cite

show abstract

“…However, power flow-based contingency analysis (CA) is not fast enough to perform an exhaustive N-1 real-time contingency analysis (RTCA) [7]. Therefore, power utilities select a subset of the contingencies for evaluation based on some pre-defined criteria [9], [10]. In [11], Huang et al stated that the size of this subset has considerable impact on RTCA solution: a large subset is computationally burdensome, while a small subset might miss critical scenarios.…”

Section: Introductionmentioning

confidence: 99%

A Graph Theoretic Approach to Power System Vulnerability Identification

Biswas

Pal

Werho

et al. 2021

IEEE Trans. Power Syst.

View full text Add to dashboard Cite

During major power system disturbances, when multiple component outages occur in rapid succession, it becomes crucial to quickly identify the transmission interconnections that have limited power transfer capability. Understanding the impact of an outage on these critical interconnections (called saturated cut-sets) is important for enhancing situational awareness and taking correct actions. This paper proposes a new graph theoretic approach for analyzing whether a contingency will create a saturated cut-set in a meshed power network. A novel feature of the proposed algorithm is that it lowers the solution time significantly making the approach viable for real-time operations. It also indicates the minimum amount by which the power transfer through the critical interconnections should be reduced so that post-contingency saturation does not occur. Robustness of the proposed algorithm for enhanced situational awareness is demonstrated using the IEEE-118 bus system as well as a 17,000+ bus model of the Western Interconnection (WI). Comparisons made with different approaches for power system vulnerability assessment prove the utility of the proposed scheme for aiding power system operations during extreme exigencies.

show abstract

“…A heuristic screening procedure is performed in the first phase to identify the most severe contingencies based on the post-contingency violations. Previously, ERCOT had approximately 3938 contingencies, including 2958 single branch contingencies, 375 double branch contingencies, and 605 generator contingencies, modeled in its system [7]. The RTCA in ERCOT executes every five minutes [7].…”

Section: Introductionmentioning

confidence: 99%

“…Previously, ERCOT had approximately 3938 contingencies, including 2958 single branch contingencies, 375 double branch contingencies, and 605 generator contingencies, modeled in its system [7]. The RTCA in ERCOT executes every five minutes [7].…”

Section: Introductionmentioning

confidence: 99%

Real-time contingency analysis with corrective transmission switching

Balasubramanian

Sahraei-Ardakani

et al. 2017

2017 IEEE Power &Amp; Energy Society General Meeting

View full text Add to dashboard Cite

Transmission switching (TS) has gained significant attention recently. However, barriers still remain and must be overcome before the technology can be adopted by the industry. The state of the art challenges include AC feasibility and performance, computational complexity, the ability to handle largescale real power systems, and dynamic stability. This two-part paper investigates these challenges by developing an AC TSbased real-time contingency analysis (RTCA) tool that can handle large-scale systems within a reasonable time. The tool proposes multiple corrective switching actions, after detection of a contingency with potential violations. To reduce the computational complexity, three heuristic algorithms are proposed to generate a small set of candidates for switching. Parallel computing is implemented to further speed up the solution time. Furthermore, stability analysis is performed to check for dynamic stability of proposed TS solutions. Part I of the paper presents a comprehensive literature review and the methodology. The promising results, tested on the Tennessee Valley Authority (TVA) system and actual energy management system (EMS) snapshots from Pennsylvania New Jersey Maryland (PJM) and the Electric Reliability Council of Texas (ERCOT), are presented in Part II. It is concluded that RTCA with corrective TS significantly reduces potential post-contingency violations and is ripe for industry adoption.

show abstract

ERCOT Control Center experience in using Real-Time Contingency Analysis in the new Nodal market

Cited by 16 publications

References 1 publication

Development of an Equivalent Circuit of a Large Power System for Real-Time Security Assessment

Development of an Equivalent Circuit of a Large Power System for Real-Time Security Assessment

A Graph Theoretic Approach to Power System Vulnerability Identification

Real-time contingency analysis with corrective transmission switching

Contact Info

Product

Resources

About