Aspects Of Power System Operation Research Articles

Measuring the volatility of wholesale electricity prices caused by wind power uncertainty with a correlation model

There is an increasing need to understand the impact of high-penetration wind power on various aspects of power system operation. This study presents a methodology to evaluate the impact of market price volatility on intermittent wind power. The proposed methodology first considers the uncertainty of wind power using a probabilistic distribution of wind speed in combination with the rated speed–MW curve. The correlation among different wind power plants is also modelled. With these statistical models, a Monte Carlo simulation (MCS) approach can be used to assess the probabilistic distribution of the price signals, that is, the probabilistic locational marginal pricing (LMP) distribution. Since the computational effort of MCS is intensive, a lookup table is proposed as preprocessing to greatly simplify the MCS. The proposed approach is tested with the PJM 5-bus system and the IEEE 118-bus system. Rules of thumb are drawn regarding the probabilistically calculated LMP and the correlation coefficients.

Computational auction mechanisms for restructured power industry operation

From the Publisher: Computational Auction Mechanisms for Restructured Power Industry Operation outlines the application of auction methods for all aspects of power system operation, primarily for a competitive environment. A complete description of the industry structure as well as the various markets now being formed is given. A thorough introduction to auction basics is included to explain how auctions have grown in other industries. Auction methods are compared to classical techniques for power system analysis, operations, and planning. The material is useful for students performing research on the new business environment based on competition. Regulators will find information on initial methods to design and evaluate market systems, and power exchange and financial analysts will find information on the interdependence of markets and power system based techniques for risk management. This information compares the new business environment solutions with old business environment solutions. Computational Auction Mechanisms for Restructured Power Industry Operation provides a first introduction to how electricity will be traded as a commodity in the future.

Auction market simulator for price based operation

Through the passage of new public utility regulatory policies, the US Federal Energy Regulatory Commission (FERC) encourages an open market system for price based operation. A previous paper describes a framework for price based operation and the associated technical issues in an auction market structure. This paper presents an auction market simulator to experimentally study the aspects of power system operation in a price-based environment. The proposed simulator can also be used as a tool to train system operators how to perform electric power transaction in the deregulated environment. This paper presents the simulation results of auction market for price based operation in the 24-bus, 10-generator IEEE Reliability Test System.

A compact algorithm for the steady-state security assessment of power systems

Security assessment is selected as one of the aspects of power system operation in most need of improvement and best suited to improvement through the use of emerging compact algorithm technologies. This paper examines some of the issues involved in actually making these improvements. The on-line steady-state security analysis of a power system requires the evaluation of the effect of all possible contingencies on the system. The traditional approach to security analysis is to test all contingencies sequentially to evaluate system performance and reliability by simulating outages of one or more generating units and transmission lines to investigate their effects on bus voltages and line power flow. In this paper, a mathematical algorithm suitable for addressing the steady-state assessment of a power system using the DC load flow technique is derived. A compact algorithm, using a reduced matrix order, has been implemented, which reduces the computation time enormously. The technique assumes that the part of the system far from a contingency is only slightly affected by the contingency or is not changed. For each contingency, the system is decomposed into three tiers, resulting in a subsystem of smaller size. The compact algorithm is applied to this subsystem to evaluate the power flow in the lines of the subsystem. The results of this proposed technique have been compared with those obtained from the standard DC load flow for the whole system and are found satisfactory within an acceptable range of accuracy with a reduction in the computation time. The IEEE 30-bus power system model was used to evaluate the algorithm.

Survey of knowledge-based systems in power systems: Europe

A survey of the development and experience with knowledge-based systems applied to power systems in Europe, including expert systems used in operation, is presented. The technical aspects of power system operation are briefly reviewed, the role of computers in power systems is discussed, and the motivation for investigating knowledge-based applications in this context is identified. The structure of the research and industrial organizations involved in the development and implementation is described, and the characteristics of main application areas are discussed. Future expert system development and implementation are discussed. >

Corona modelling in power system operation

A phenomenological transmission line corona model is proposed to accommodate the different aspects of power system operation. Another model is also proposed to represent the effect of leakage current on high voltage insulators, with and without local discharge formation on their surface, in severe environmental conditions. Both the corona and leakage current models are then used as elements of the transmission line discretized model. This paper presents a more accurate solution at voltage buses by considering the corona effects as a variable shunt admittance depending on the updated voltage values which are calculated from each iteration in the load flow technique. A technique is proposed for reactive power optimization to find the control variables of switchable VAR sources which satisfy the operating system constraints and minimize a suggested objective function. The objective function is intended to minimize the costs of both the consumed switchable VAR sources and the active power losses in the transmission line, taking into consideration the corona and leakage current effects. The minimization of the consumed VAR sources aims to reduce the overvoltage which increases the corona loss in power systems. A trade-off between the danger of corona existence and the advantages of overvoltage on the power factors is presented using the suggested performance indices of the bus voltages and power factors in the system. The feasibility of the proposed models and techniques is tested by applying them to the IEEE 14-bus test system.