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This paper discusses design and application of the multiagent simulation technology aiming to meet smart grid requirements. The difference between multiagent systems and multiagent simulation in smart grid applications is clarified. The state-of-the-art applications of multiagent simulation in power and energy systems are classified based on the simulation environment. The paper also addresses the interface issues including synchronization and data distribution for multiagent co-simulation. In addition, the emerging research paradigms in smart grid multiagent simulation are identified. [ABSTRACT FROM PUBLISHER]

This paper presents a review with a concise description and analysis of the fundamentals, characteristics, analytical details, merits, and drawbacks associated with existing methods in frequency and time domain for harmonic analysis in practical power networks. The description and analysis are centered on methods developed in the harmonic domain, hybrid frequency-time domain, and time domain, respectively. Validation of the reviewed methods for harmonic analysis, against one of the widely accepted digital simulators, such as EMTP, EMTDC, or MATLAB/SIMULINK, is reported in the cited individual contributions. [ABSTRACT FROM PUBLISHER]

This task force paper presents multi-domain tools and their interfacing issues to perform simulations that require expertise in multiple areas of physics, such as electrothermal, electromechanical, electrochemical, and electromagnetic simulations, etc. Features of single multi-domain simulation tools, which are capable of simulating more than one system such as electrical chemical, mechanical, etc., are discussed. In addition, programs that are not capable of performing multi-domain simulation independently but can be interfaced with other programs to perform multi-domain simulation are also covered. Two case studies are reported where multi-domain simulations are performed in offline and real-time environments through the interfacing of more than one simulation tool. [ABSTRACT FROM PUBLISHER]

Electric power distribution systems of many commercial and industrial sites often employ variable frequency drives and other loads that internally utilize dc. Such loads are often based on front-end line-commutated rectifiers. The detailed switch-level models of such rectifier systems can be readily implemented using a number of widely available digital programs and transient simulation tools, including the Electromagnetic Transient (EMT)-based programs and Matlab/Simulink. To improve the simulation efficiency for the system-level transient studies with a large number of such subsystems, the so-called dynamic average models have been utilized. This paper presents the average-value modeling methodologies for the conventional three-phase (six-pulse) front-end rectifier loads. We demonstrate the system operation and the dynamic performance of the developed average models in discontinuous and continuous modes, as well as under balanced and unbalanced operation. [ABSTRACT FROM PUBLISHER]

This paper presents a brief review of techniques available for reducing large systems to smaller equivalents. This paper is divided into high frequency equivalents, low frequency equivalents, and wideband equivalents. Numerical examples are presented to demonstrate selected methods of high frequency equivalencing. [ABSTRACT FROM PUBLISHER]

Real-time testing of new and more sophisticated distributed resource interfaces during transients, representing the different physical parts (mechanical, thermal, hydraulic, chemical, electrical, electronics) of a nonconventional generator in a single platform, or analyzing the interactions of distribution systems with distributed generators, energy markets, and customer behaviors are scenarios that cannot be studied with current software packages. This paper analyzes the present status and discusses the future development of tools that could cope with these simulation challenges. This paper includes test cases that will illustrate the scope of some of these simulation tools. [ABSTRACT FROM AUTHOR]

Distribution software packages were primarily designed for analyzing radial systems with very limited capabilities for representing distributed resources (DR). Software manufacturers are presently updating and expanding the capabilities of their tools. The challenges, however, are many, since the new tools should be able to represent a wide range of power component models, efficiently compute steady-state and transient unbalanced operating conditions, or cope with DR interconnections whose design cannot be anticipated yet. This paper summarizes the main types of studies related to planning, analysis, and design of distribution networks, analyzes the models required for representing distributed resources, and discusses the future capabilities of distribution software packages. This paper includes test cases that illustrate some of the studies related to planning, analysis, and design of distribution networks with penetration of DR. [ABSTRACT FROM AUTHOR]

This paper deals with the current state-of-the-art in interfacing issues related to real-time digital simulators employed in the simulation of power systems and power-electronic systems. This paper provides an overview of technical challenges encountered and their solutions as the real-time digital simulators evolved. Hardware-in-the-loop interfacing for controller hardware and power apparatus hardware are also presented. [ABSTRACT FROM AUTHOR]

Modeling and analysis of power and power-electronic systems' transients using digital programs enables testing new design concepts in modern electric grid and many industrial and commercial products and applications. This paper gives an overview of dynamic average-value modeling techniques for representing static switching converters for the system-level studies. Concepts and desirable properties of averaged models for conducting large-signal time-domain transient studies and small-signal frequency-domain analysis for control design tasks are discussed. Basic approaches for developing average models for dc/dc and dc/ac converters are briefly reviewed and summarized. Finally, the desirable properties of the average-value models are demonstrated through an example system. [ABSTRACT FROM PUBLISHER]

The electromagnetic transient programs (EMTP-like tools) are based on the nodal (or modified nodal) equations that enable an efficient numerical solution and, subsequently, fast time-domain simulations. The state-variable-based simulation programs, such as Simulink, are also used for studying the dynamics of electrical systems. Both the offline and real-time versions of these two types of simulation tools are widely used by the researchers and engineers in industry and academia to study the transient phenomena and dynamics in power systems with rotating electrical machines. This paper provides a summary of the interfacing techniques that are utilized to integrate the general-purpose models of electrical machines with the rest of the power system network for these studies. The interfacing methods are broadly classified as indirect and direct approaches. The paper also describes the numerical properties as well as limitations imposed by the interfacing of the commonly used machine models that should be considered when selecting the simulation parameters and assessing the final results. [ABSTRACT FROM AUTHOR]

Transient stability (TS) and electromagnetic transient (EMT) programs are widely used simulation tools in power systems, with distinct applications but competing requirements. TS programs are fast which makes them suitable for handling large-scale networks, however, the modeling is not sufficiently detailed. On the other hand, EMT simulators are highly detailed, but limited in speed; consequently, they are used to simulate only small portions of the network. Integrating these two types of simulators generates a hybrid simulator which inherits the merits of both programs. A hybrid simulator can fulfill the modeling requirements of a large network by providing a fast as well as a detailed simulation. Establishing a connection between two different programs brings up several important issues which have been addressed, classified, and explained in this paper. An alternative integrated modeling of TS and EMT is also discussed using the concept of frequency shifting. [ABSTRACT FROM AUTHOR]

Some of the most remarkable issues related to interharmonic theory and modeling are presented. Starting from the basic definitions and concepts, attention is first devoted to interharmonic sources. Then, the interharmonic assessment is considered with particular attention to the problem of the frequency resolution and of the computational burden associated with the analysis of periodic steady-state waveforms. Finally, modeling of different kinds of interharmonic sources and the extension of the classical models developed for power system harmonic analysis to include interharmonics are discussed. Numerical results for the issues presented are given with references to case studies constituted by popular schemes of adjustable speed drives. [ABSTRACT FROM AUTHOR]

This paper presents a new approach for the real-time digital simulation of power electronic controllers in power systems. Digital controllers for power electronic systems present a problem when testing in real-time using a digital simulator due to the discrete nature of their outputs, which are not necessarily in synchronism with the time step of the simulator. The proposed algorithm combines the variable step-size numerical integration method with linear interpolation for the synchronization of a real-time digital simulator and a digital controller. It is shown that lack of such synchronization leads to inaccurate simulation results, specifically with regard to the fundamental and harmonics of the voltage and current signals. Sampling theory is used to model the interaction between a digital simulator and a digital controller. A pulse width modulated (PWM) voltage source converter (VSC) based reactive power compensator system is used as an illustrative example for the simulation. [ABSTRACT FROM PUBLISHER]

This paper proposes large-scale transient stability simulation based on the massively parallel architecture of multiple graphics processing units (GPUs). A robust and efficient instantaneous relaxation (IR)-based parallel processing technique which features implicit integration, full Newton iteration, and sparse LU-based linear solver is used to run the multiple GPUs simultaneously. This implementation highlights the combination of coarse-grained algorithm-level parallelism with fine-grained data-parallelism of the GPUs to accelerate large-scale transient stability simulation. Multithreaded parallel programming makes the entire implementation highly transparent, scalable, and efficient. Several large test systems are used for the simulation with a maximum size of 9,984 buses and 2,560 synchronous generators all modeled in detail resulting in matrices that are larger than 20\,000\times 20\,000. [ABSTRACT FROM AUTHOR]

Shunt capacitors are extensively used in power systems for voltage support and power factor correction. The proliferation of harmonic-producing loads significantly increases the possibility of system-capacitor resonance. As a result, a practical and easy-to-use procedure to estimate the severity of harmonic resonance is of good interest to industry. The objective of this paper is to present such a method. The paper first proposes a harmonic resonance index. By taking into account the IEEE harmonic limits and the capacitor loading limits, a harmonic resonance chart is developed. A detailed harmonic analysis of the system is needed only if the system condition is located in certain regions of the chart. Examples are given to show how the possibility and severity of harmonic resonance can be estimated using the proposed guideline. [ABSTRACT FROM PUBLISHER]