Sudhir K. Agarwal

Balancing cost and reliability: a quantitative study at Atlantic Electric

This paper documents a system improvement study conducted by Atlantic Electric (AE) Company using EPRIs reliability analytical tools. With increased emphasis on customer service, reliability and cost control, AE is striving to balance the value of supply reliability to its customers with the costs of system improvement. The paper presents a dollar value quantification of the level of reliability inherent in a given system improvement option. Based on this quantification, the improvement option that best balances the improvement cost and the incremental reliability is selected. Reliability indices including the expected unserved energy (EUE) were computed for each improvement option. Using the EUE, the value of service unreliability to the customers was computed for each option. Dollar value based analysis is then performed to balance cost and reliability quantitatively. A selection process that a utility engineer or system planner may go through to arrive at the option that best balances the cost and reliability of system improvement is covered in the paper.

Reporting bulk power system delivery point reliability

This paper is part of an ongoing activity of the IEEE Application of Probability Methods Subcommittee to advance the probabilistic methods used to analyze bulk power system (BPS) reliability. The objective of the Task Force is to develop a set of guidelines for measuring delivery point reliability. This involves reviewing published literature and other documentation of existing procedures, definitions, and indices. This report presents the results of the Task Force efforts to compile a useful set of terms and procedures for consistent reporting of BPS delivery point reliability.

Effects of dependent and common mode outages on the reliability of bulk electric system - Part II: Outage data analysis

A companion paper (Part I) presents the basic concepts of dependent and common mode outages, the causes for their origins in the bulk electric system (BES) and the subsequent effects from a reliability perspective. This paper describes the practical outage data collection efforts in vogue in North America and parts of Europe, with particular emphasis on outage data statistics corresponding to dependent and common mode outages. The goal is to eventually be able to obtain standard, representative reliability indices for typical transmission elements such as lines and transformers from the available outage data.

Research on Common-Mode and Dependent (CMD) Outage Events in Power Systems: A Review

The purpose of this paper is to present a review of some fundamental concepts and practical applications in the area of common-mode and dependent (CMD) outage events in power systems. The paper is a result of ongoing activity carried out by the Probability Applications for Common and dependent Mode Events (PACME) Working Group (WG) of the Reliability, Risk and Probability Applications Subcommittee. The PACME WG was formed in 2010 to review, advance, and present the research and practical applications in the area of CMD outage events. This paper presents state-of-the-art in research, modeling, and applications of CMD outage events in power system planning and operation. Issues considered include: data monitoring and collection, and probabilistic modeling and evaluation in the planning, and operation of power generation and transmission systems. Additionally, some results obtained from outage data statistics corresponding to CMD outage events in systems such as Generating Availability Data System, Transmission Availability Data System, and Canadian Electrical Association are presented.

Effects of dependent and common mode outages on the reliability of bulk electric system - Part I: Basic concepts

This paper is the first part of a two-part paper based on the ongoing activity carried out by the Task Force (TF) of the Working Group (WG) on Probability Applications for Common Mode Events (PACME) in electric power systems under the Reliability, Risk and Probability Applications (RRPA) Subcommittee. The primary objectives of this work are to (1) review and discuss the basic definitions of dependent, common-mode and cascading outage events, (2) identify the major causes of common-mode, dependent and cascading outages, (3) recognize the effects of protection system failures and misoperations on the Bulk Electric System (BES), and (4) assess the impact of weather related outages and extreme events on the performance of the BES. The scope of Part I is limited to the basic concepts on common-mode and dependent outages. The overall goal of the two papers is to assist the wider efforts within the industry in practically assessing the effects of dependent and common-mode outages on the reliability of BES.

Reliability assessment of multiple substations in Idaho system using a node-breaker model

The reliability performance of transmission substations and switching stations is critical to the overall system reliability. The outage of an element in a substation can result in multiple outages of other network elements, such as lines and transformers, and can lead to cascading events. Traditionally, probabilistic techniques have been applied to a bus-branch (BB) model, and to assess the impact of substation-related outages, it was necessary to manually add substation configurations. This paper presents an approach for assessing the reliability of multiple substations in Idaho Power Company (IPC) system using a detailed node-breaker (NB) model representation. The paper also presents an approach to automatically generate a large number of contingencies from the NB model that can be used in complying with the North American Electric Reliability Corporation (NERC) Transmission System Planning Performance Requirements (TPL) and performing system reliability studies. The presented approach is illustrated using a portion of the actual IPC system that includes all 230 kV and higher voltage substations.