Hughes, R.C.; Lightfoot, H.A.; McComb, T.R.. Author Affiliation: National Grid ... Author Affiliation: Iowa State University; Virginia Polytechnic In- stitute and State ...
Assuring the Quality of Impulse Voltage Calibration Results Issued by a Calibration Laboratory
Discussion Deadline: August 2002
Power System Operations
A Study on Determination of Interface Flow Limits in the KEPCO System Using Modified Continuation Power Flow (MCPF) Abstract: This paper reports a study on determining the steady-state voltage stability limit of interface flow on a set of interface lines between the metropolitan region and the neighboring regions in the Korea Electric Power Corporation (KEPCO). The interface flow limit considering severe contingencies is determined with a concept of interface flow margin, which is the active power flow margin of the key transmission lines between one region and others under a fixed load demand condition. The paper proposes a procedure to determine secure limit of active power flow on a set of specified interface lines. The procedure uses the modified continuation power flow (MCPF) tracing a path of power flow solutions with respect to generation shift to vary interface flow. In simulation, voltage stability limits of the metropolitan interface flow of the 1998 KEPCO system are determined. Keywords: Interface flow limit, KEPCO system, modified continuation power flow, steady-state voltage stability. Preprint Order Number: PE-754PRS (03-2002) Discussion Deadline: August 2002
Leader-Follower Framework for Control of Energy Services
Power System Relaying
Hughes, R.C.; Lightfoot, H.A.; McComb, T.R. Author Affiliation: National Grid Co.; NRC. Abstract: This paper describes high-voltage impulse measurements made under the controlled conditions of a calibration or national measurement laboratory to establish the best agreement that could be achieved in comparison measurements on small reference dividers. This comparison to establish mutual international traceability between NRC and National Grid has shown that the peak voltage of a smooth lightning impulse was measured by both laboratories to within 0.2% with an estimated uncertainty of ±0.2% at a level of confidence not less than 95%. The authors make recommendations on how calibrations of reference measuring systems should be performed. Keywords: High-voltage impulse measurement, traceability, calibration, quality assurance. Preprint Order Number: PE-028PRD (03-2002) Discussion Deadline: August 2002
Keyhani, A. Author Affiliation: The Ohio State University. Abstract: This paper presents a framework for leader-follower control of energy services. In this framework, the main emphasis is to provide market players with proper economic signals in order for the market to function efficiently in light of market players profit motives and system reliability and security requirements. The problem formulation and the data needed for the implementation of the proposed framework are also presented. Keywords: Energy services market, reliability and competitiveness of operation, predictive market monitoring, leader-follower optimization. Preprint Order Number: PE-374PRS (03-2002) Discussion Deadline: August 2002
An Information Architecture for Future Power Systems and Its Reliability Analysis Xie, Z.; Manimaran, G.; Vittal, V; Phadke, A.G.; Centeno, V Author Affiliation: Iowa State University; Virginia Polytechnic Institute and State University. Abstract: Analysis of 162 disturbances from 1979-1995 reported by the North American Electric Reliability Council (NERC) indicates the importance of information systems under the regulated and competitive environment. This paper points out the major deficiencies in current communication and information systems and proposes a new power system information architecture aimed at correcting these deficiencies. The proposed architecture includes automation and control systems at all levels, from substation control system to independent system operator (ISO) operating center, taking into account the requirements of real-time data, security, availability, scalability, and appropriate quality of service. It uses multiple communication channels employing a wide variety of technologies to transmit real-time operating data and control signals. The real-time operating and control system is modeled with various redundancy configurations. The reliabilities of different configurations are studied and compared for practical values of component failure rates and repair rates. Keywords: Power system, EMS/SCADA, real-time, fault-tolerance, information architecture, communication technology, Internet, VPN, MPLS, reliability, failure rate, repair rate. Preprint Order Number: PE-594PRS (03-2002) 60
A New Optimal Approach for Coordination of Overcurrent Relays in Interconnected Power Systems Askarian Abyaneh, H.; Al-Dabbagh, M.; Kazemi Karegar, H.; Hesameddin Hossein Sadeghi, S.; Abul Jabbar Khan, R. Author Affiliation: Amir Kabir University of Technology; RMIT University. Abstract: A new method for optimum coordination of overcurrent relays is proposed. The proposed method is based on only constraints. Minimization is inherently included by setting the time dials to minimum and increasing their values gradually. Configuration changes of the network is taken into account. The method does not need any initial solution. It can consider both linear and nonlinear relay characteristics models. The optimal settings of overcurrent relays for eight-bus and England Norweb networks are obtained, and comparison between the new method and existing methods is made. Keywords: Linear programming, optimal co-ordination, overcurrent relay. Preprint Order Number: PE-877PRD (03-2002) Discussion Deadline: August 2002
New Algorithm To Phase Selection
Based on Wavelet Transforms
Youssef, O.A.S. Author Affiliation: Suez Canal University. Abstract: In long line applications that involve tripping the faulted phase in case of LG faults, single-pole autoreclosure is extensively used. Traditional phase selectors can suffer some deficiencies in their performance due to varying system and fault conditions. However, the advent of wavelet transform techniques with their ability to focus on system transients provides an effective and reliable method for accurate and fast phase selection. This work describes the design and implementation of a new technique using wavelet transform algorithms. The technique is based on utilizing sharp transitions generated on the faulted phase. The paper presents the wavelet transform concept and its value in classification techniques and feature detection schemes. Feature extraction principle is derived. Generated data from the simulation IEEE Power Engineering Review, June 2002
