Showing papers on "Power system simulation published in 1972"
TL;DR: The development of a model suitable for power system operation over periods of time of the order of one or more years and based on probability techniques is described.
Abstract: The optimisation of power system operation over periods of time of the order of one or more years requires simulation models which combine reasonable accuracy with high computation speed The development of a model suitable for such studies and based on probability techniques is described
311 citations
TL;DR: In this paper, a procedure for determining the optimal plan for the expansion of the generation facilities of a power system over a long period of time is described, based on probabalistic simulation methods and an advanced dynamic programming formulation of the problem.
Abstract: The paper describes a procedure for determining the optimal plan for the expansion of the generation facilities of a power system over a long period of time. A method of production costing based on probabalistic simulation methods is combined with an advanced dynamic programming formulation of the problem in order to treat uncertainty in a systematic manner.
83 citations
01 Jan 1972
TL;DR: The generalized reduced gradient (GRG), one of the most elegant nonlinear-programming techniques, is described and it is shown how it can be extended to solve optimum power flows of very high dimension (of the order of several thousand nodes).
Abstract: Since the development of sparsity techniques by Tinney, the power-flow program has become an extremely effective and often used tool for planning electric power networks. This program solves for the unknowns--voltages, phase angles, etc.--of a set of simultaneous nonlinear algebraic equations, the ac power-flow equations. The optimum power flow is likely to replace, in due time, the normal power flow in many important planning functions discussed in this paper. A number of mathematical programming techniques have recently been studied to solve the optimum power flow and several small-to-medium sized experimental programs have been written. The generalized reduced gradient (GRG), one of the most elegant nonlinear-programming techniques, is described and it is shown how it can be extended to solve optimum power flows of very high dimension (of the order of several thousand nodes). This extension consists mainly of using sparsity techniques in several of the solution steps of the GRG.
65 citations
TL;DR: In this paper, the authors focus on the simulation of the system response following a prescribed disturbance, which is the most accurate method for large-scale studies of complex systems and their response to disturbances.
Abstract: As systems have increased in size and complexity, and as the number of firm-power ties between systems have increased, the nature of the system stability problems has changed. Furthermore, there is also a demand for more accurate engineering analysis of these complex problems. Although much effort has been devoted to searching for alternate methods, the practical and effective method for large-scale studies is still the simulation of the system response, with time, following a prescribed disturbance. This emphasis on simulation necessarily requires system and equipment models which adequately represent their behavior over some time span, usually less than 20 seconds.
37 citations
TL;DR: An experimental general-purpose process-control digital- computer system provides high-speed phase-and ground-distance fault protection of one 230 kV transmission line and an automatic oscillograph and diagnostic programs will allow a study of field performance.
Abstract: An experimental general-purpose process-control digital- computer system described in a companion paper (I-System Description) provides high-speed phase-and ground-distance fault protection of one 230 kV transmission line The stored program performs all of the relaying functions using the output of an analog-to- digital converter which reads the instantaneous value of the power- system currents and voltages Model line tests described here form the basis for preliminary performance evaluation An automatic oscillograph and diagnostic programs will allow a study of field performance
37 citations
TL;DR: Dynamic energy balance is a new technique for power system dynamic simulation as discussed by the authors, which requires about one tenth the computatioanl effort of a transient stability study yet gives similar results so far as frequency transients are concerned.
Abstract: Dynamic energy balance is a new technique for power system dynamic simulation. It requires about one tenth the computatioanl effort of a transient stability study yet gives similar results so far as frequency transients are concerned. Applications, methodology and comparison with a transient stability study are treated in this paper.
34 citations
TL;DR: A simulation a roach suitable for non-linear analysis of the dynamic berformance of large power systems is developed and Organization of system equations is evolved so as to permit rapid solution employing one level iteration of the resulting algebraic equations.
Abstract: A simulation a roach suitable for non-linear analysis of the dynamic berformance of large power systems is developed. The problem of matching machine and network equations forms an important criterion in the development of the machine model. Among the major aspects treated is the influence of amortisseur circuits. Organization of system equations is evolved so as to permit rapid solution employing one level iteration of the resulting algebraic equations, which account for a very significant portion of the total computing time. In part II of this paper, network solution procedures and results of investigations carried out on typical systems are presented.
26 citations
TL;DR: In this article, a direct method is introduced for minimizing the shift of generation required to meet temporary operating criteria, such as the elimination of overload lines or transformers, or fixed flows on inter-ties or critical lines.
Abstract: A direct method is introduced for minimizing the shift of generation required to meet temporary operating criteria, such as the elimination of overload lines or transformers, or fixed flows on inter-ties or critical lines. Also, a linear model for multiple contingencies is presented.
23 citations
Enel1
TL;DR: In this article, the authors show the advisability of making use of a couple of risk indices in terms of curtailed energy and abruptly disconnected power in considering the reliability of a power system.
Abstract: In considering the problem of quantitative evaluation of the reliability of a power system for planning purposes, the authors show the advisability of making use of a couple of risk indices in terms of curtailed energy and abruptly disconnected power.
22 citations
TL;DR: The machine modelling and organization of machine-network interconnection equations are discussed and comparisons are made between the use of a large scale computer program, and a specialized simulation approach when determining the value of damping forces present when large sources of generation are perturbed and angular swings develop between such sources, and persist for several seconds.
Abstract: Comparisons are made between the use of a large scale computer program, and a specialized simulation approach, when determining the value of damping forces present when large sources of generation are perturbed and angular swings develop between such sources, and persist for several seconds. In part I of this paper, the machine modelling and organization of machine-network interconnection equations are discussed.
14 citations
TL;DR: Computer results are given showing the electric transients during line charging of a 3-phase, transposed system as well as the traveling waves on transposed and untransposed 3- phase systems during3-phase and line-to-ground faults.
Abstract: A method of analysis convenient for the simulation of transposed and untransposed transmission systems is set forth, and the facility of the hybrid computer in studying the traveling waves on these systems is illustrated. In particular, computer results are given showing the electric transients during line charging of a 3-phase, transposed system as well as the traveling waves on transposed and untransposed 3- phase systems during 3-phase and line-to-ground faults. Also presented are computer results showing the line-charging transients of two mutual- ly coupled, untransposed, 3-phase transmission systems. The material presented in this paper should permit a broader base from which to evaluate the various methods of analysis and simulation of traveling waves on transmission systems.
TL;DR: This paper presents a general, systematic formulation of the problem of dynamic analysis of multi-machine power systems for digital simulation using a generalized machine model which enables one to consider the affect of network response in more detail than described in the literature.
Abstract: This paper presents a general, systematic formulation of the problem of dynamic analysis of multi-machine power systems for digital simulation. The analysis utilizes a generalized machine model which enables one to consider the affect of network response in more detail than described in the literature. The techniques of solution are discussed in order to indicate the structure of numerical computation.
TL;DR: In this paper, the authors investigated the use of hybrid computer systems for the solution of problems associated with the generation and transmission of electrical power and found that a special purpose hybrid system could provide simulations of power system transient disturbances 100 times faster than real time.
Abstract: This paper summarizes the results of an investigation into the use of hybrid computer systems for the solution of problems associated with the generation and transmission of electrical power. In particular the study was conducted to determine if hybrid computing techniques could result in the capability of real time, or faster, transient stability studies. It was determined that a special purpose hybrid system could provide simulations of power system transient disturbances 100 times faster than real time.
TL;DR: In this paper, a complete and comprehensive mathematical model of phase shifting components is developed using a delta-wye transformer bank as an example of a typical phase shifting component, and the V-equivalent is incorporated into the network matrix called ZBUS which is then used in the short circuit equations for a line-toground fault.
Abstract: A complete and comprehensive mathematical model of phase shifting components is developed using a delta-wye transformer bank as an example of a typical phase shifting component. Linear graph theory techniques are used to form the model which is called a V-equivalent. The V-equivalent is incorporated into the network matrix called ZBUS which is then used in the short circuit equations for a line-to-ground fault. In this paper, a numerical example utilizing a sample power system is used to illustrate the method by which the V-equivalent of a delta-wye transformer bank is incorporated into a digital computer program for short circuit studies. The results of the digital computer program demonstrate that, by the use of the V- equivalent, phase shifting components such as delta-wye transformers can be made an integral part of the power system model. A single line-to-ground fault can occur on either side of the delta-wye transformer bank, and the correct values of the currents and voltages at the fault and throughout the system can be obtained directly from the solution of the system model. No subsequent calculations are necessary to correct for the effect of the phase shift.