A. P. Sakis Meliopoulos

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This paper addresses numerical oscillations encountered in power system dynamic simulation resulting from trapezoidal numerical integration rule. Two methods are presented to eliminate the numerical oscillations: trapezoidal with numerical stabilizer method and Gear’s second order method. A detailed comparison is given regarding the accuracy of the(More)
Control room operators are faced with frequent security-economy decision-making situations necessitated by stressed system operating conditions, and there is increased need for securityeconomy decision-support tools. Although probabilistic methods are promising in this regard, they have been mainly used in planning environments. This task force paper(More)
Abstract A new tool for computing and visualizing the operation of power system components and systems is presented. One component of the tool is a time domain simulator that operates in the background within a multitasking environment. Visualization and animation objects can retrieve data in real time from the time domain simulator and display a detailed(More)
This paper presents the application of the virtual test bed for visualization and animation of protective relaying problems. The development of protective relaying animation and visualization objects as well as the interfacing with the virtual test bed is described. Two examples of protective relaying animation are presented: (a) modified mho relays and (b)(More)
Empirical evidence shows that the clearing prices for point-to-point congestion revenue rights, also known as financial transmission rights (FTRs), resulting from centralized auctions conducted by Independent System Operators differ significantly and systematically from the realized congestion revenues that determine the accrued payoffs of these rights. The(More)
The most common load type consists of induction motors. The operational characteristics of these motors play an important role in the power system operation and control. More accurate models of induction machines will result in more realistic power system simulation. This is particularly important in today’s environment where power systems are operated(More)
Expert-system-based approaches to complex computational procedures of transients in power systems are desirable because power systems contain complex and nonlinear elements. We propose the use of symbolically-aided modeling as the basis for the design of expert transient simulators. The symbolic approaches work well when (a) the user interface is(More)
A new model for studying synchronous machine dynamic behavior is developed and implemented in the Virtual Test Bed (VTB) simulation environment. The nonlinear synchronous machine model uses quantities in phase coordinates. The advantages of phase-domain modeling for electric machines are discussed. The new model was applied in the study of startup(More)