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Steady state power flow simulation software is widely used across industry and academia for reliable system operation. Voltage regulation implementation in software typically makes use of PQ and PV buses separately resulting in an infinite slope QV curve, while units in industry typically have dead-bands and real sloped responses. In this work, a new technique for modeling power flow generator voltage control is implemented to more accurately model the real-world generator responses. The new technique has been compared with typical power flow control methods using a three-bus case study that portrays the differences in the two response types. The results obtained show that the new technique is more effective at modeling dead-bands and real sloped responses that exist in industry.

Canola (Brassica napus L.) is the most widespread profitable cash crop in Canada. In 2014 and 2015, direct-seeded experiments were conducted in 16 western Canada environments. “Small” canola seed (average 3.32–3.44 g 1000−1) was compared to “large” canola seed (average 4.96–5.40 g 1000−1) at five seeding rates (50, 75, 100, 125 or 150 seeds m−2). Large canola seeds increased crop density and crop biomass but decreased plant mortality, days to start of flowering, days to end of flowering, days to maturity, and percent green seed. Seed size did not influence harvested seed weight, seed oil content or seed protein content. Increasing the seeding rate of small seeds improved canola yield, but the same response did not occur for large seeds. Increasing seeding rates also increased crop density, plant mortality, crop biomass, and seed oil content, but decreased days to start of flowering, days to end of flowering, days to maturity, percent green seed, and seed protein content. Seeding rate had no impact on harv...

Simulation and analysis of power systems often involves modeling extremely complex systems. This is particularly true when the model involves not just the electrical power system, but also other networks layered on top of the power system, such as the accompanying financial transactions. Such layered networks can often involve interactions that are not at all obvious. Interactive visualization can be a very effective means for determining otherwise hidden relationships between various elements in the network. This paper describes the application of interactive 3D for the visualization of electric power system operational and economic data. The paper first presents a 3D, one-line-based visualization and then provides several examples of how it could be used to display power system data.

The value of trembling aspen (Populus tremuloides Michx.) as a resource has increased in Canada in recent years, but key information regarding the health of this species and its interrelationships with biotic and abiotic agents is lacking. A regional study was conducted to (i) assess the general health of trembling aspen trees in the three prairie provinces of Canada, (ii) determine the incidence of biotic and abiotic agents affecting these trees and (iii) determine what factors most influenced the health of trembling aspen trees between forest tent caterpillar (Malacosoma disstria Hubner) outbreaks. A total of 8296 trembling aspen trees in 85 plots were monitored during 1992–1994. Trembling aspen health was assessed and related to biotic and abiotic damage agents and symptoms. Trembling aspen in the study area were generally healthy: crowns were in good condition, trees had few pests, and mortality rates were low. Confidence intervals for proportion of trees dead less than 2 years are reported by age class. Large aspen tortrix (Choristoneura conflictana [Wlk.]) and poplar peniophora (Peniophora polygonia [Pers.:Fr.]) Boud. were the most common pests, occurring on 15 and 13% of live trees, respectively; incidences of other pests were

In the new world of competition, power traders, grid managers, public service boards, and the public itself all need to take in what's happening at a glance. Visualization software enables viewers to interpret the data more rapidly and more accurately than ever before. This kind of software will become still more useful, even indispensable, as electricity grids are integrated over ever-larger areas, as transmission and generation become competitive markets, and as transactions grow in number and complexity. Concepts like power flow, loop flow, and reactive power, which once mattered only to the engineers directly involved in grid operations, now must be made intuitive. This is because they must be communicated to public service commissions and the consumer-voters to whom such boards are answerable. In short, whether the client/user is a power marketer, a grid operator or manager, a public authority, or a member of the public, power system visualization tools can aid their comprehension by lifting the truly significant above background noise. Such tools can expedite decision-making for congestion management, power trading, market organization, and investment planning for the long term.

Power system engineers are presented with vast amounts of information to analyze during daily operations. In systems containing thousands of buses, it can be very difficult to assess the state of the power system in an intuitive and rapid manner. The paper discusses the use of contours for visualizing power system voltage data. Also, because of the low computation requirements of the contouring algorithm, the algorithm is implemented into a real-time animation of the voltage profile of a power system. The contouring routines are implemented into the PowerWorld/sup TM/ Simulator software package, with results shown for systems with up to several thousand buses. Experiments and interviews with system engineers are also discussed to measure the applicability of voltage contouring as an add-on to practical EMS systems.

Summary A commercial assay for human TGF-β1 was validated for use on equine synovial fluid and serum. This assay was then used to determine concentrations of TGF-β1 in synovial fluid samples from 109 metacarpophalangeal joints of horses with varying age, gender, and joint condition. No difference in concentration was found between geldings and females. A difference (p=.04) was found between young horses (≤48 months, 1101 pg/ml) and old horses (≥120 months, 863 pg/ml), and between horses with visibly normal joints and those with severely diseased joints (885 versus 1002 pg/ml, p=0.01). These findings suggest concentrations of TGF-β1 are elevated in joints from younger horses and joints with gross evidence of disease.

This paper presents a methodology for integrated power flow modeling of the impact of geomagnetic disturbances (GMDs) on power system voltage stability. GMDs cause quasi-dc, geomagnetically induced currents (GICs) in the transformers and transmission lines, which in turn cause saturation of the high voltage transformers, greatly increasing their reactive power consumption. GICs can be calculated using standard power flow modeling parameters such as line resistance, augmented with several GIC specific fields including substation geographic coordinates and grounding resistance, transformer configuration, and transformer coil winding resistances. When exact values are not available, estimated quantities can be used. By then integrating GIC into power flow analysis, the changes in reactive power losses and bus voltages can be quantified to assess the risk of voltage instability and large-scale voltage collapse. An example calculation is provided for a North American Eastern Interconnect model.

This paper describes research in progress for a panel session presentation on how phasor measurement unit (PMU) values can be used to improve power system operations beyond their use in state estimation.

Transmission planning should seek to maintain or improve system security over time and facilitate robust wholesale power markets by improving transmission capacity for bulk transfers across wide regions. Uncertainty about the development of future generation resources and regulatory policies complicates the process for long- range transmission planning. Furthermore, the evolution toward regional transmission planning requires that planners analyze and suggest improvements over significantly larger networks than have been studied in the past. Methods are required to screen numerous alternatives to determine those that offer the most cost effective means of security enhancement. This paper presents a methodology for using linear sensitivity analysis to evaluate potential transmission connections and aid selection of those that provide the most cost-effective improvements to overall system security. The methodology is applied to the planning of an extra high-voltage (EHV) overlay for the Southwest Power Pool (SPP) regional transmission system.

Effective power system operation requires power system engineers and operators to analyze vast amounts of information. In systems containing thousands of buses, a key challenge is to present this data in a form such that the user can assess the state of the system in an intuitive and quick manner. This is particularly true when trying to analyze relationships between actual network power flows, the scheduled power flows, and the capacity of the transmission system. With restructuring and the move towards having a single entity, such as an independent system operator or pool, operate a much larger system, this need has become more acute. This paper presents several power system visualization techniques to help in this task. These techniques include animation of power system flow values, contouring of bus and transmission line flow values, data aggregation techniques and virtual reality data visualization.

Effective power system operation requires power system engineers and operators to analyze vast amounts of information. The authors have developed several techniques for visualizing large amounts of data including contouring, animated flows, and 3D visualization. These techniques have been completely integrated into PowerWorld Simulator, an offline system study tool for use in the energy industry. Integrating these visualization techniques with real-time data sources, such as those available in energy control centers, however, has presented a separate challenge to the wide dissemination of these visualization abilities. The paper presents a case study of integrating these abilities with control centers that utilize the Plant Information (PI) System for data storage and archival. Projects have been completed that integrate these visualization techniques into control centers for Commonwealth Edison in Lombard, Illinois and City Water Light and Power in Springfield, Illinois. A separate pilot project has also been completed with the Tennessee Valley Authority.

Electricity markets involve suppliers (generators) and sometimes consumers (loads) bidding for MWhr generation and consumption. In this market model, a central operator selves an optimal power flow (OPF) based on the maximization of social welfare to determine the generation and load dispatch and system spot prices. In this structure, market participants will choose their bids in order to maximize their profits. This presents a two-level optimization problem in which participants try to maximize their profit under the constraint that their dispatch and price are determined by the OPF. This paper presents an efficient numerical technique, using price and dispatch sensitivity information available from the OPF solution, to determine how a market participant should vary its bid portfolio in order to maximize its overall profit. The paper further demonstrates the determination of Nash equilibrium when all participants are trying to maximize their profit in this manner.

Simulation and analysis of power systems often involves modeling extremely complex systems. This is particularly true when the model involves not just the electrical power system, but also other networks layered on top of the power system, such as the accompanying financial transactions. Such layered networks can often involve interactions that are not at all obvious. Interactive visualization can be a very effective means for determining otherwise hidden relationships between various elements in the network. This paper describes a 3D virtual environment developed to allow users to interactively visualize such information and relationships. The paper describes the architecture used to develop this environment, and then provides several examples of how the environment is used to provide an interactive visualization of power system economic and security information.

This paper discusses the assessment and visualization of market power in bulk electricity markets, with the explicit consideration of transmission system constraints. In general, market power is the ability of a particular seller or group of sellers to maintain prices profitably above competitive levels for a significant period of time. When an entity has mid exercises market power, it ceases to be a price taker and becomes a price maker. The restructuring of the electric industry in many parts of the world has encouraged competitive markets with the objective of reaping the benefits of lower prices and innovation that competition can provide. Such benefits are not attainable when a player utilizing the electric transmission system may exert market power. This paper describers the procedures for analyzing and visualizing such situations.

This paper describes a user-friendly power simulation package for teaching power system operations and control. This Microsoft Windows(R) based program simulates power system operation over a specified time period (of typically several hours to a day). Students dynamically interact with the simulated system through various windows, including a one-line display. The use of data files and option windows allows the program to simulate a wide variety of different power systems and operating problems.

We investigate the simulation of real and reactive power spot markets. While spot pricing of real power remains a viable option for the creation of a power system market, the future of a reactive power spot market remains cloudy. The large capital investment portion needed in pricing reactive power as well as the highly volatile nature of reactive power spot prices makes the creation of such a market difficult. In spite of this, a portion of the pricing scheme that is used for reactive power will likely be based on the spot pricing approach as this provides the most accurate signal for near real time system operation. The paper builds on a simple modification to the standard optimal power flow (OPF) in order to simulate the spot markers for real and reactive power. To achieve this, price dependent load models are introduced for both real and reactive power.

The authors investigate the inclusion of price-dependent loads into the traditional optimal power flow algorithm. The development of the model will be based on the solution of the OPF using an objective function for maximization of social welfare. The paper shows that a traditional OFF algorithm that minimizes supplier costs can be modified to solve the social welfare maximization problem by including price-dependent load models. This modification to the standard OPF is intuitive and very simple. They show this modified OPF formulation facilitates simulation of a spot market for electricity. While the development in the paper accounts for both real and reactive power supply and consumption, the examples in the paper concentrate on real power markets. The algorithm is demonstrated on a range of practical examples, including several small systems, and on a system with over a hundred buses. The impact of such price dependent loads on congestion and bus marginal costs is highlighted.

Various proposals have been made for new paradigms for operating the restructuring electrical system. One of the key challenges associated with this restructuring is to effectively analyze and evaluate the effects these alternative paradigms may have on major aspects of power system operations, including the so called ancillary services. The paper provides preliminary results on the development of a simulation tool to perform this analysis. Since power systems are ultimately governed by the laws of physics, the heart of the tool is a power system simulation engine, valid over a simulated time frame of minutes to days. The modular structure of the tool then allows other packages to be superimposed on this structure to represent different proposed paradigms. Integration of effective visualization into an interactive simulation environment is then used to gain understanding and insights concerning the attributes of each paradigm.

The introduction of competition in electricity markets has given rise to the problem of strategic bidding by rational market participants (or players) in pursuit of individual profit (or welfare) maximization. Given the simultaneous action of all players, Nash equilibria are the solutions in the bidding space that simultaneously satisfy their individual objectives. The paper addresses the problem of finding Nash equilibria in a centralized competitive electricity market (PoolCo model) in which we assume that the players have reasonable estimates about all the other players' utility functions. In addition, we assume that a central decision maker-the independent grid operator or IGO-dispatches the market using an OPF tool that accepts as its inputs the bids and offers freely submitted by the participants. The paper shows how to search for multiple equilibria in a systematic manner if we make specific assumptions for the grid model and for the utility functions.

One area in need of new research in information visualization is the operation and analysis of large-scale electric power systems. In analyzing power systems, one is usually confronted with a large amount of multivariate data. With systems containing tens of thousands of electrical nodes (buses), a key challenge is to present this data in a form so the user can assess the state of the system in an intuitive and quick manner. This is particularly true when trying to analyze relationships between actual network power flows, the scheduled power flows, and the capacity of the transmission system. With electric industry restructuring and the move towards having a single entity, such as an independent system operator or pool, operate a much larger system, this need has become more acute. This paper presents several power system visualization techniques to help in this task. These techniques include animation of power system flow values, contouring of bus and transmission line flow values, data aggregation techniques and interactive 3D data visualization.

This paper provides a methodology to examine the impact of transmission constraints on the efficient operation of large scale power markets. The Northeast USA is presented as a case study. A system model was first constructed using the publicly available US Federal Energy Regulatory Commission (FERC) Form 715 filings to provide a detailed representation of the transmission system. FERC Form 1 data and information from the US Energy Information Administration's (EIA) National Energy Modeling System model were used to represent generator costs. An optimal power flow (OPF) was then used to optimally dispatch a large system consisting of the New England Region (NEPOOL), New York (NYPP), and the NERC MAAC and ECAR regions, both under base case and modified conditions. Using the OPF results, the costs associated with transmission constraints are determined. Finally, given the large amount of data generated by these studies, methods for the efficient visualization of the results are also discussed.

A complete product study of the reaction of 3-chloro-1-ethylpiperidine (1) in aqueous sodium-hydroxide showed the formation of three bis-(β-aminoethers), 2,2′-bis-(N-ethyl-2-pyrrolidinomethyl) ether (6), 3-(N′-ethyl-2′-pyrrolidinomethoxy)-N-ethylpiperidine (7) and 3,3′-bis-N-ethyl-3-piperidinyl ether (8) in addition to the two previously reported products. The structures of these three ethers are demonstrated and their formation is shown to be consistent with the previously suggested mechanism1 of the reaction. Reactions of 2-chloromethyl-1-ethylpyrrolidine (2) are shown to proceed by the same mechanistic pathways with the formation of the same products. Reaction of 1 or 2 with two other nucleophiles, methoxide and ethoxide are also examined.