N-equivalent circuit

For a steady-state analysis, a cable can be expressed by a single or a cascaded n-equivalent circuit instead of a distributed parameter line. In the EMTP, even if a cable is represented by a constant-parameter line model (Dommel s line model) or a frequency-dependent line model (Semiyen s or Marti s line model), the distributed parameter line is internally converted into a n-equivalent circuit and is passed to a steady-state analysis routine. 

If the cable impedance and admittance per unit length are provided by the cable manufacturer, the data of the n-equivalent circuit can be easily calculated with the cable length. The cable impedance and admittance can be calculated by cable constants or cable parameters installed in the EMTP using the physical parameters of the cable. The parameters shown in Table 4.2 are generally provided by the manufacturer. 

Then applying Thevenin s " theorem, the equivalent circuit can be represented as show n in Figure 18.18(b). On application of a voltage surge, the arrester will start... 

Figure 23.22 Equivalent circuit for n number of capacitor bank already switched on the circuit and another (C ) being switched...

Now an equivalent circuit, which takes into account both the ion transport along the TC and the charge transfer through the carbon electrode material to the current collector, may be represented as in Fig. 2, wherein N = a(c)/4r, Cm and Rm are the total NP capacitance and resistance in a unit electrode volume (defined here as a product of a unit electrode area and the tier thickness), Re is the electrical resistance of an electrode in the same unit... 

Fig. 19 (a) The device schematic for a pseudo Y-junction transistor, (b) SEM micrograph of the overall circuit arrangement used in the measurement of the electrical characteristics, with Au contact pads and an FIB-patterned Pt wire contacting the Au pads and the Y-junction. (c) The ambipolar I-V curves resemble that of an n-type semiconductor at a positive gate potential, and a p-type semiconductor at a negative gate potential top), and the equivalent circuit for a pseudo Y-junction SWNT device bottom). (Reprinted with permission from [170, 171])... 

A similar procedure can be used to determine the space charge distribution in n-type Si in the dark with a positive bias polarization so as to generate a depletion layer within the semiconductor substrate. In this case, the situation is somewhat different because the positive polarization in HF results in an anodic etching of the sample with a nonnegligible current density near 7 pA cm . Nevertheless, similar results were obtained, the components of the equivalent circuit were a capacitance of a few 10 F cm , and a resistance term ranging from 1 to 10Mf2cm for a bias potential varying from —0.1 to -1-0.9 V vs. SCE. 

Find the charge-transfer resistance (/ CT), the double-layer capacitance (CDL), and the solution resistance (Rso]n) from the data listed in Table P.4 by using the simplest equivalent circuit for an electrochemical reaction shown in the figure. If the measurement was carried out at equilibrium potential, what is the exchange current (Kim)... 

The Relaxation Spectrum Analysis was carried out for a cell consisting of n-CdSe in a liquid junction configuration with NaOH/S=/S 1 1 1M as the electrolyte. Three parallel RC elements were identified for the equivalent circuit of this cell, and the fastest relaxing capacitive element obeys the Mott-Schottky relation. 

Fig. 6.4 The characteristic frequencies of the equivalent circuit exaggerating the differences between fm,fs and fT and between /a,/p and/n.

Fig. 17. The equivalent circuit and cross-sectional view of an inverter with a n-channel enhancement mode driver FET and a p-channel load FET. [From Nara and Matsumura (1982).]...

Note that only at the output terminals n-n are the Thevenin and Norton equivalents the same. In other words, at the output terminals n-n the voltage and current of the Thevenin equivalent circuit and the Norton equivalent circuit are identical. 

Figure 5.17. Equivalent circuit of a PEM fuel cell, with a and b H2/02 gas supply, and c symmetrical gas supply [19]. (With kind permission from Springer Science+Business Media Journal of Applied Electrochemistry, Characterization of membrane electrode assemblies in polymer electrolyte fuel cells using a.c. impedance spectroscopy, 32, 2002, 859-63, Wagner N, Figure 3, 2002 Springer.)...

Figure 5.34. Electric equivalent circuit for the impedance spectra in Figure 5.37. Ref. ohmic resistance Rct charge-transfer resistance CPE constant phase element IV Warburg element. The subscripts a and c denote anode and cathode, respectively [36]. (Modified from Boillot M, Bonnet C, Jatroudakis N, Carre P, Didierjean S, Lapicque F. Effect of gas dilution on PEM fuel cell performance and impedance response. Fuel Cells 2006 6 31-7. 2006 John Wiley Sons Limited. Reproduced with permission, and with the permission of the authors.)...

Figure 6.33. Equivalent circuit for evaluation of the interpolated impedance spectra measured in galvanostatic operation of a fuel cell during CO poisoning of the anode [33], (Reprinted from Journal of Power Sources, 127(1-2), Wagner N, Gulzow E. Change of electrochemical impedance spectra (EIS) with time during CO-poisoning of the Pt-anode in a membrane fuel cell, 341-7, 2004, with permission from Elsevier and the authors.)...

Where the electrode is rough owing to inadequate etching after a mechanical polish, the equivalent circuit may become very complex. An example, for n-Ti02 in 1M NaOH, is [80]... 

Fig. 40. Equivalent circuit appropriate to the geometry of Fig. 40. The resistance ifp/n represents the resistance of the p/n junction formed under strong depletion or inversion.

Fig. 97. (a) Electrical equivalent circuit of an illuminated semiconductor electrolyte interface, (b), (c) Experimental impedance plots for n-GaAs/selenide under 22mWcnT2 illumination at different potentials, (b) V = -0.60V/SCE (in the photocurrent saturation region) (c) V = - 1.575 V/SCE (in the onset region). The circles are experimental points and the dotted curve is the best fit to (a). 

Fig. 98. (A) Current-voltage curves for n-GaAs/selenide junction under (a) 1.5 mW cm 2, (b) 9mWera"2, (c) 22raWcm"2, and (d) 50mWcm"2. (B) Mott-Schottky plots using data from the equivalent circuit of Fig. 97(a) at light intensities as in (A). The line (e) was obtained in the dark and gives Vn, - 2.06 V/SCE.

If bulk recombination is important in the depletion layer, then we cannot separate hole and electron flows in the above manner and the Zr, / scp network collapses to a frequency-independent resistor I D, as shown in Fig. 100. In this figure IFis a Warburg impedance for the hole current. This is too complex, as it stands, for analysis and a simpler case can be derived if Css is dominant and the frequency range is such that W can also be neglected. Under these circumstances, I D, Raan and 7 ssp further collapse to a simple resistor Rr, leading to the equivalent circuit shown in Fig. 101, which has been applied to p-GaAs under illumination and n-GaAs under hole injection. 

The equivalent circuits (Figure 3.5) can be used to describe the electrical response of the perturbed device. The lumped-element model. Figure 3.Sb, is most convenient to use. When the resonator has a surface perturbation, the motional impedance increases, as represented by the equivalent-circuit model of Figure 3.7. This model contains the elements C , Li, C, and Ri corresponding to the unperturbed resonator. In addition, the surface perturbation causes an increase in the motional impedance Z(n as described by the complex electrical element Ze in Figure 3.7a. This element is given by [12]... 

EIS has been used to study the kineties of outer-sphere redox reactions at semiconductors in the dark (Meier et al., 1991 Meier et al., 1999). The reactions involve majority carriers (electrons for n-type materials), and the electrode behaves like a metal with a low and potential-dependent electron density. The EIS response can be modelled by the equivalent circuit shown in Eig. 12.1, where is interpreted as the faradaic resistance obtained by linearising the potential dependence of the current associated with electron transfer to the redox species. 

Figure 6. The effect of the measuring current frequency on the Mott-Schottky plot." " C and R are the capacity and resistance in the parallel equivalent circuit of the electrode is the value of R extrapolated to infinite frequency, (a) CdSe (N - 10 cm ) in 0.25 M K2SO4 + 0.25 M CH3COOH + 0.05 M CH3COONa frequency 1-320,...

FIGURE 3.18 Apparent equivalent circuit for the YSZ-based sensor using a ZnCr204-SE. (Reprinted from Miura, N., Nakatou M., and Zhuiykov, S., Impedancemetric gas sensor based on zirconia solid electrolyte and oxide sensing electrode for detecting total NO at high temperature, Sens. Actuators B, Chem. 93 (2003) 221-228, with permission from Elsevier Science.)... 

An equivalent definition for ring is an n-membered circuit that represents the shortest possible path connecting all the [n(n-l)/2] pairs of nodes belonging to that circuit. 

This replacement was necessary to adapt the equivalent circuit to the nonideal behaviour of the aluminium oxide film. The exponent n of the CPE element can be regarded as a measure of the inhomogeneity of the film structure [17]. For an ideal capacitor the exponent n is one. For the calculation of the CPE values, the fitting program in Ref [18] was used. 

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