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Power Flow and Electric Machinery Basics
Published in Pedro Ponce, Arturo Molina, Omar Mata, Luis Ibarra, Brian MacCleery, Power System Fundamentals, 2017
Pedro Ponce, Arturo Molina, Omar Mata, Luis Ibarra, Brian MacCleery
Power lines connect generators to loads, transmitting electrical power from one to the other with minimal losses. Power lines are usually divided into two categories: transmission lines and distribution lines. Transmission lines are designed to transmit electrical power efficiently over long distances. They run at very high voltages to reduce the resistive (I2R $ I^2 R $ ) losses in the lines. Once the power reaches the vicinity of the user, its voltage is stepped down, and the power is supplied through distribution lines to the final customers. Distribution lines carry much less power than transmission lines, and for shorter distances, so they can operate at lower power voltages without prohibitive losses.
New PV Markets Sustaining Mass Production
Published in Peter F. Varadi, Wolfgang Palz, Michael Eckhart, Allan R. Hoffman, Paula Mints, Bill Rever, John Wohlgemuth, Frank P.H. Wouters, Sun Towards High Noon, 2017
In general, grids are collections of wires, switches, transformers, substations, and related equipment that enable the delivery of electrical energy from a generator to a consumer of that energy. Most people are familiar with elevated wires strung between grid poles in our cities and byways. The first grid, for delivery of alternating current (AC) electricity, was put into operation in 1886. For more than a century, the traditional grid has been a one-way distribution network that delivers power from large centralized power generating stations to customers via a radial network of wires. Regional grids, when integrated, constitute a national grid, something the United States and other national electric utility systems are still trying to achieve. Transmission lines are long-distance carriers of electrical energy transmitted at high voltages and low currents to minimize electrical losses due to heating in wires. This high voltage is then reduced via transformers to lower voltage, usually 120 or 240 volts, to supply local distribution networks that bring the energy to our homes and businesses. The US Energy Information Administration estimates that national electricity transmission and distribution (T&D) losses average about 6% of the electricity that is transmitted and distributed in the United States each year.
Filters
Published in Geoff Lewis, Communications Technology Handbook, 2013
This theory starts with a filter structure which is analysed, usually assuming perfect components, to obtain the necessary information about its characteristics. The complete study requires a knowledge of the characteristic impedance Z0 and propagation constant γ, over the frequency range of interest. The characteristic impedance is defined in the same way as for a transmission line; that is, the input impedance of an infinite number of identical sections connected in series, or the input impedance of one section when terminated in that value of impedance. The propagation constant is complex and given by γ = α + jβ where α, the real part, reflects the attenuation and β, the imaginary part, relates to the phase shift through the filter.
Breast Cancer Detection by Terahertz UWB Microstrip Patch Antenna Loaded with 6X6 SRR Array
Published in IETE Journal of Research, 2023
Kritika Singh, Marshal Dhayal, Smrity Dwivedi
The reflection Coefficient is indicated as S11. It is the ratio of the reflected power to the incident power, expressed in decibels (dB). The reflection coefficient can be defined as the ratio of the amplitude of the reflected wave to the amplitude of the incident wave at the interface between the antenna and the transmission line. [53]. The S11 graph of the microstrip patch antenna can provide information about the antenna's ability to detect tumors in breast tissue. Specifically, changes in the reflection coefficient at certain frequencies can indicate the presence of a tumor, since tumors can alter the dielectric properties of the surrounding tissue. From Figure 7 it can be observed that the antenna has a large bandwidth, hence it can be used for various biomedical applications.
A brief introduction to nomography: graphical representation of mathematical relationships
Published in International Journal of Mathematical Education in Science and Technology, 2019
One significant nomographic application is the elaborate (and, indeed, beautiful) Smith chart [28–30], which continues to be used by electrical engineers for calculations relating to transmission lines and impedance matching. An ancient application of nomography (even if not generally recognized as such) is on sundials [31], where the upright gnomon (note the presence of ‘nomo’) casts a moving shadow, which thus acts as the isopleth, on the face of the sundial. A set of nomographs for predicting fire behaviour in vegetation [32] demonstrates an application which would likely prove helpful in emergency situations.
Machine learning based fault detection approach to enhance quality control in smart manufacturing
Published in Production Planning & Control, 2023
There are numerous distinct transmission line configurations, such as single and double circuit lines, long and short transmission lines, etc. There are several methods for quickly and accurately simulating the network under various power system conditions; each disruption causes the electrical energy platform’s features to alter. Thus, neural networks are able to account for the dynamic changes in power systems. Due to the fact that an ANN's operation depends on a number of straightforward actions, depending on how well-trained it is, its output is very speedy, reliable, and precise.