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chapter1
chapter1

... • ICs have made digital systems more reliable by reducing the number of external interconnection from one device to another. • ICs have reduced the amount of electrical power needed to perform a given function. • IC cannot handle very large currents or voltages because the heat generated in such sma ...
TRANSFORMER
TRANSFORMER

... This indicates the emf at the secondary winding is equivalent to the emf of the primary winding ...
F. Radiometers
F. Radiometers

... important equation is called the ideal radiometer equation for a total-power receiver. The weakest detectable signals ÁT only have to be several (typically five) times the output rms ÛT given by the radiometer equation, not several times the total system noise Tsys . The product Á·RF Ü may be quite ...
IV. Strategy of the Efficient Parallel GA for OPF
IV. Strategy of the Efficient Parallel GA for OPF

... total generation cost taken as a secondary strategy. This paper presents an efficient decomposed GA to enhance the solution of the Optimal Power Flow (OPF) with non-smooth cost function and under severe loading conditions. At the decomposed stage the length of the original chromosome is reduced succ ...
SGA8543Z HIGH IP , MEDIUM POWER DISCRETE SiGe TRANSISTOR
SGA8543Z HIGH IP , MEDIUM POWER DISCRETE SiGe TRANSISTOR

... RFMD’s SGA8543Z is a high performance Silicon Germanium Heterostructure Bipolar Transistor (SiGe HBT) designed for operation from 50MHzto3.5GHz. The SGA8543Z is optimized for 3.3V operation but can be biased at 2.7V for low-voltage battery operated systems. The device provides low NF and excellent l ...
NK2422032209
NK2422032209

... unbalanced voltages will occur at supply side these can be eliminated by using Multi level Inverter. In this paper a closed loop Control system is designed using PI controller in order to maintain load voltage constant for under voltage and Over voltage conditions and MATLAB simulations have been ca ...
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... Most of the industrial applications use any one of the basic DC-DC converter configurations namely buck, boost, buck–boost, and Cuk converters. These converters are non-isolating converters. Buck-boost converters use inductors for storing energy from the source and release the same to load or output ...
Line to Ground Voltage Monitoring on Ungrounded
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... For a three phase system this principle is shown graphically in Figure 2. The reference point for voltages (Vx) can be any point. In the case of the metering system discussed in this paper, this point is taken to be the earth potential. This point does not have to be the neutral of the system. With ...
12 dBm OCP Millimeter-wave 28 nm CMOS Power
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... A number of realizations of 60-GHz PAs in 65nm CMOS have been reported [5-9]. As a means of attaining high output power levels, parallel amplifying topologies including power combining structures are widely used. The drawback has been that most of these implementations have displayed a considerably ...
IOSR Journal of Electrical and Electronics Engineering (IOSR-JEEE) e-ISSN: 2278-1676,p-ISSN: 2320-3331,
IOSR Journal of Electrical and Electronics Engineering (IOSR-JEEE) e-ISSN: 2278-1676,p-ISSN: 2320-3331,

... In high power rectifiers Switch mode AC-DC converters are being used as front end rectifiers for variety of applications due to the advantage of high efficiency and power density [2]. These switched mode ac to dc converters, also draw non sinusoidal input current with low power factor and high harmo ...
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RF5765 2.4GHz to 2.5GHz 802.11b/g/n WiFi FRONT-END MODULE Features

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... of which play important roles in the STATCOM dynamics. An improved model, referred to in this paper as the “first small signal model” (Model II) is proposed in this present work, making use of the relationship between  and m ( m c ). ...
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... • L2/C3/C4: Placed to optimize input match, and enhance out of band low frequency stability. • R2: Optionally placed to increase bias current and IP3. It has been found that 20Ω value is best case (see graph section of data sheet). • L1/C1: Influence output return loss. RF3861 has internal DC blocki ...
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... reactive power is either under or over supplied, the voltage on the network may rise or fall to a point where generators must switch off to protect themselves thereby decreasing the generation and cause further problems. As can be seen from the phase diagram, increasing the reactive power increases ...
Lecture 2: Fundamentals and Trends
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... some reference machine, and means of normalized execution times are computed, only the geometric mean gives consistent results no matter what the reference machine is  This has led to declaring the geometric mean as the preferred ...
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Aalborg Universitet Islanded Microgrids
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... objective is to obtain a negative sequence equivalent circuit, as shown in Fig. 3 (b), for analyzing negative sequence voltage changes in each bus. However, the negative sequence quantities cannot be considered separately from positive sequence. Assuming the presence of unbalanced loads in different ...
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Power Network-on-Chip for Scalable Power Delivery
Power Network-on-Chip for Scalable Power Delivery

Voltage Sag Protection
Voltage Sag Protection

... Current inrush following voltage sag Overheating due to current harmonics Copyright © 2012 Rockwell Automation, Inc. All rights reserved. ...
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Decibel

The decibel (dB) is a logarithmic unit that expresses the ratio of two values of a physical quantity, often power or intensity. One of these quantities is often a reference value and in this case the decibel expresses the absolute level of the physical quantity. The number of decibels is ten times the logarithm to base 10 of the ratio of two power quantities, or of the ratio of the squares of two field amplitude quantities. One decibel is one tenth of one bel, named in honor of Alexander Graham Bell; however, the bel is seldom used.The definition of the decibel is based on the measurement of power in telephony of the early 20th century in the Bell System in the United States. Today, the unit is used for a wide variety of measurements in science and engineering, most prominently in acoustics, electronics, and control theory. In electronics, the gains of amplifiers, attenuation of signals, and signal-to-noise ratios are often expressed in decibels. The decibel confers a number of advantages, such as the ability to conveniently represent very large or small numbers, and the ability to carry out multiplication of ratios by simple addition and subtraction. By contrast, use of the decibel complicates operations of addition and subtraction.A change in power by a factor of 10 is a 10 dB change. At the half power point an audio circuit or an antenna exhibits an attenuation of 3dB. A change in voltage by a factor of 10 results in a change in power by a factor of 100, which is a 20 dB change. A change in voltage ratio by a factor of two approximately corresponds to a 6 dB change.The decibel symbol is often qualified with a suffix that indicates the reference quantity that has been used or some other property of the quantity being measured. For example, dBm indicates a reference power of one milliwatt, while dBu is referenced to approximately 0.775 volts RMS.In the International System of Quantities, the decibel is defined as a unit of measurement for quantities of type level or level difference, which are defined as the logarithm of the ratio of power- or field-type quantities.
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