The aim of this paper is to assess the capability of the emerging synchronized phasor measurement technology in improving the overall stability of the Hydro-Quebec transmission system through supplementary modulation of voltage regulators. Following a thorough singular value and eigenvalue analysis of the system dynamic interactions, five control sites consisting of four generators and one synchronous condenser are chosen to implement new power system stabilizers with a supplementary input from remote phasor measuring units, geographically spread over nine electrically coherent areas. Since the remote feedback loops are built on top of an existing decentralized control system, this design approach results in a decentralized/hierarchical control architecture with significant advantages in terms of reliability and operational flexibility. A systematic control and measurement pairing yielded four dominant natural loops, each associated with a significant open-loop inter-area oscillatory mode at 0.06, 0.4, 0.7 and 0.95 Hz respectively. These PSSs have a speed sensitive local loop operating in the usual way, and a wide-area measurement based global loop which involves a single differential frequency signal between two suitably selected areas. The tuning and coordination technique for these advanced multiple input signals PSSs is described. Their impacts on the system is assessed using both small-signal analysis and nonlinear simulations in a transient stability program. Wide-area stabilizing controllers have a significant potential in improving the dynamic performance of the Hydro-Quebec's existing power system.

Wide-area measurement based stabilizing control of large power systems-a decentralized/hierarchical approach

This paper proposes a vision of next-generation monitoring, analysis, and control functions for tomorrow's smart power system control centers. The paper first reviews the present control center technology and then presents the vision of the next-generation monitoring, analysis, and control functions. The paper also identifies the technology and infrastructure gaps that must be filled, and develops a roadmap to realize the proposed vision. This smart control center vision is expected to be a critical part of the future smart transmission grid.

https://web.eecs.utk.edu/~fli6/Publications/PZhang10JP.pdf

Next-Generation Monitoring, Analysis, and Control for the Future Smart Control Center

Power systems are subjected to a wide range of small or larger disturbances during operating conditions. Small changes in loading conditions occur continually. The power system must adjust to these changing conditions and continue to operate satisfactorily and within the desired bounds of voltage and frequency. The power system should be designed to survive larger types of disturbances, such as faults, loss of a large generator, or line switching. Certain system disturbances may cause loss of synchronism between a generator and the rest of the utility system, or between interconnected power systems of neighboring utilities. If such a loss of synchronism occurs, it is imperative that the generator or system areas operating asynchronously are separated immediately to avoid widespread outages and equipment damage. In this paper we describe the philosophy and application fundamentals of out-of-step protection in transmission systems. We also discuss recent enhancements in the design of out-of-step tripping and blocking protection functions that improve the security and reliability of the power system. In addition, we demonstrate the out-of-step phenomena and distance relay element behavior using EMTP and Matlab simulations.

/pdf/out-of-step-protection-fundamentals-and-advancements-3gunoj8u95.pdf

Out-of-step protection fundamentals and advancements

This paper provides a comprehensive state-of-the-art overview on power infrastructure defense systems. A review of the literature on the subjects of critical infrastructures, threats to the power grids, defense system concepts, and the special protection systems is reported. The proposed Strategic Power Infrastructure Defense (SPID) system methodology is a real-time, wide-area, adaptive protection and control system involving the power, communication, and computer infrastructures. The SPID system performs the failure analysis, vulnerability assessment, and adaptive control actions to avoid catastrophic power outages. This paper also includes a new concept for bargaining by multiagents to identify the decision options to reduce the system vulnerability. The concept of a flexible configuration of the wide-area grid is substantiated with an area-partitioning algorithm. A 179-bus system is used to illustrate the area partitioning method that is intended to minimize the total amount of load shedding.

/pdf/strategic-power-infrastructure-defense-3vhpa2bhb4.pdf

Strategic Power Infrastructure Defense

This paper presents a critical review on different application of Phasor Measurement Units (PMUs) in electric power system
networks incorporated with FACTS controllers for advanced power system monitoring, protection, and control. Also this paper
presents the current status of the research and developments in the field of the applications of PMUs in electric power system
networks incorporated with FACTS controllers. Authors strongly believe that this survey article will be very much useful to the
researchers for finding out the relevant references in the field of the applications of PMUs in electric power system networks
incorporated with FACTS controllers.

/pdf/applications-of-phasor-measurement-units-pmus-in-electric-o612nuurst.pdf

Applications of phasor measurement units (PMUs) in electric power system networks incorporated with FACTS controllers

The electricity generation, transmission and distribution systems in major countries are planned, operated and protected so as to withstand any hazards that are likely to most affect them (short circuits, tripping of a line or generating set), without damage to customers. However, compliance with normal dependability and security practices does not result in a fully safe system protected against major collapses. These may result from the accidental coincidence of more fragile operating conditions and serious damage or from many successive adverse hazards far beyond those against which precautions are generally taken. This paper describes a coordinated power system defense plan, the goal of which is to prevent large regions of France or the entire power network from suffering blackouts and to accelerate restoration.

O. Faucon

Papers

Coordinated defense plan protects against transient instabilities