Impedance in transmission line

To minimize reflections, the characteristic impedance of the transmission line and the impedance of the load circuit have to be equal (or "matched"). If the impedance matches, the connection is known as a matched connection, and the process of correcting an impedance mismatch is called impedance matching. Since the characteristic impedance for ...

Impedance in transmission line. Introduction. This calculator is a tool for designing balanced transmission lines with a specific desired characteristic impedance 𝑍c Z c and made of parallel square stock conductors of a given side length 𝑑 d. This type of transmission line is frequently encountered as a feed line on antenna booms, especially with log-periodic dipole arrays.

7.6.4 Impedance of a Transmission Line At l = λ ∕4. When the distance from the input of the transmission line to the load is a multiple of λ∕4 (βl = nπ∕2) and therefore l = nλ∕4 (where n is an integer), the input impedance to the transmission line \( \underline {Z}_{in}(l)\) is :

M.H. Perrott Macro-modeling for Distributed, Linear Networks Z1 Z3 Zs V s ZL Linear Circuits & Passives (1) Z2 Linear Circuits & Passives length = d1 length = d2 (2) length = d3 delay1 = velocity d1 = LCd1 = μεd1 delay2 = μεd2 delay3 = μεd3 Vout Model transmission line as a delay element If lossy, could also add an attenuation factor (which is aThe coaxial cable, along with the balanced two-wire, is the most common type of transmission line used in RF communications. This calculator helps you calculate the characteristic impedance of a coaxial cable given its dimensions. This will also provide the time delay the cable provides for a signal and also the capacitance and inductance per ...This article offers an introduction to the Smith chart and how it’s used to make transmission-line calculations and fundamental impedance-matching circuits.In other words, if the load impedance is equal to the transmission line characteristic impedance, the input impedance will be likewise be equal to Z 0 regardless of the transmission line length A. 4. L L ZjX= If the load is purely reactive (i.e., the resistive component is zero), the input impedance is: Z 0,β A Z L=Z 0 in 0 ZZ=4 Comments. Simply put, differential impedance is the instantaneous impedance of a pair of transmission lines when two complimentary signals are transmitted with opposite polarity. For a printed circuit board (PCB) this is a pair of traces, also known as a differential pair. We care about maintaining the same differential impedance for the same ...Lossless Transmission Line. Although it is practically impossible to design a lossless transmission line, we can minimize losses by considering parameters like characteristic/surge impedance (Z o).But before diving into these parameters, we should have a look at what really is the idea behind lossless transmission lines and why is it so important in power system analysis.With this transmission line we associate the load reflection coefficient, , given by (1.1) This load reflection coefficient can be expressed in terms of the normalized load impedance by dividing the numerator and denominator by the characteristic impedance of the line, Z C. (1.2) or (1.3) where (1.4)Surge Impedance is the characteristic impedance of a lossless transmission line. It is also called Natural Impedance because this impedance has nothing to do with load impedance. Since line is assumed to be lossless, this means that series resistance and shunt conductance is negligible i.e. zero for power lines.

Equation (2.17) gives the input impedance for a transmission line of length d, wave impedance Z o, space frequency β, terminated in load Z L. ... but go through a calibration procedure so the instrument knows the transmission line parameters, especially its electrical length. If you are using an instrument that doesn't do it for you, proceed ...765-kV transmission line with aluminum guyed-V towers (Courtesy of American Electric Power Company) 4 ... Series resistance accounts for ohmic ðI2RÞ line losses. Series impedance, including resistance and inductive reactance, gives rise to series-voltage drops along the line. Shunt capacitance gives rise to line-charging currents.Coaxial cable is a particular kind of transmission line, so the circuit models developed for general transmission lines are appropriate. See Telegrapher's equation . Schematic representation of the elementary components of a transmission line Schematic representation of a coaxial transmission line, showing the characteristic impedance Z 0 ...765-kV transmission line with aluminum guyed-V towers (Courtesy of American Electric Power Company) 4 ... Series resistance accounts for ohmic ðI2RÞ line losses. Series impedance, including resistance and inductive reactance, gives rise to series-voltage drops along the line. Shunt capacitance gives rise to line-charging currents.The characteristic impedance (Z 0) of a transmission line is the resistance it would exhibit if it were infinite in length. This is entirely different from leakage resistance of the dielectric separating the two conductors, and the metallic resistance of the wires themselves.A transmission line’s termination impedance is intended to suppress signal reflection at an input to a component. Unfortunately, transmission lines can never be perfectly matched, and matching is limited by practical factors. Some components use on-die termination while others need to have it applied manually.A transmission line’s termination impedance is intended to suppress signal reflection at an input to a component. Unfortunately, transmission lines can never be perfectly matched, and matching is limited by practical factors. Some components use on-die termination while others need to have it applied manually.PowerWorld Transmission Line Parameter Calculator v.1.0 Power Base: The system voltampere base in MVA. Voltage Base: The line-line voltage base in KV. Impedance Base: The impedance base in Ohms. This value is automatically computed when the power base and the voltage base are entered or modified. Admittance Base: The admittance base in Siemens.

This page titled 3.9: Lossless and Low-Loss Transmission Lines is shared under a CC BY-SA 4.0 license and was authored, remixed, and/or curated by Steven W. Ellingson (Virginia Tech Libraries' Open Education Initiative) via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.1- Assume the load is 100 + j50 connected to a 50 ohm line. Find coefficient of reflection (mag, & angle) and SWR. Is it matched well? 2- For a 50 ohm lossless transmission line terminated in a load impedance ZL=100 + j50 ohm, determine the fraction of the average incident power reflected by the load. Also, what is theTransmission line impedance equation determined from circuit analysis. This equation is derived from an equivalent lumped element circuit model for a transmission line. Note that the equivalent capacitance and inductance in this equation are related to the geometry of the transmission line and the material properties of the conductor and ...The impedance value you calculate is the transmission line impedance the signal sees as it reflects off the mismatched load and travels on the line. In the limit of a very long transmission line (such as when the line length is many multiples of the wavelength), then the tanh function eventually converges to 1.These sections of transmission lines are collectively called transmission line transformers. Multi-section and tapered transformers connect between the input and output ports to match the impedance. The required impedance and passband properties are attained by varying the number of sections or length of transmission line transformers.7 abr 2021 ... This paper presents an impedance-based method to estimate the fault location in transmission lines. The mathematical formu lation considers the ...

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This simply means that this value will remain constant for a given transmission line. This value will not change due to change in length of line. The value of surge impedance for a typical transmission line is around 400 Ohm and that for a cable is around 40 ohm. Notice that the value of surge impedance for cable is less than that of ...When you need to analyze signal behavior on a transmission line for a given load component, the load capacitance will affect S-parameters and the transmission line’s transfer function, so it needs to be included in high speed/high frequency signal analysis. In addition, the real input impedance at the load is determined by the load ...Impedance Matching between Source and Load. In the basic crude basic block diagram, we have a source, transmission line and load, all having an impedance of 50Ohms. But according to maximum power transfer theorem, we need the source impedance to be equal to the load impedance for maximum power transfer. But there is a transmission line in the ...The impedance ranges of transmission lines that are usually encountered in practice are given below. Note that a strip line is a rectangular conductor over a ground with the width of the conductor begin much greater than its thickness. This type of conductor is encountered in printed circuits, for example.

What does this mean in a transmission line problem? When we close the switch a voltage will begin to travel toward the load at the phase velocity of the transmission line. ... Its magnitude is as calculated from the source voltage and impedance and the line impedance, (it only sees the line impedance, it doesn't know there is a load at the ...Summarizing: Equation 3.15.1 is the input impedance of a lossless transmission line having characteristic impedance Z0 and which is terminated into a load ZL. The result also depends on the length and phase propagation constant of the line. Note that Zin(l) is periodic in l.An open-circuited transmission line can be used as a circuit element called an open stub, which is a short section of a transmission line connected in parallel with the main line. An open stub can be used for impedance matching, filtering, or other purposes, depending on its length and position relative to the main line.A short transmission line is classified as a transmission line with:. A length less than 80km (50 miles) Voltage level less than 69 kV; Capacitance effect is negligible; Only resistance and inductance are taken in calculation capacitance is neglected.; Medium Transmission Line. A medium transmission line is classified as a transmission line with:. A length more than 80 km (50 miles) but less ...The goal in exploring design space is to find a combination of parameter values that optimizes some feature, while maintaining the target impedance. The challenge for fine line analysis is that the aspect ratio of trace thickness to line width can exceed 1, which means approximations are not suitable for analysis.The transmission line input impedance is related to the load impedance and the length of the line, and S11 also depends on the input impedance of the transmission line. The formula for S11 treats the transmission line as a circuit network with its own input impedance, which is required when considering wave propagation into an electrically long ...The transmission line has mainly four parameters, resistance, inductance, capacitance and shunt conductance. These parameters are uniformly distributed along the line. Hence, it is also called the distributed parameter of the transmission line. The inductance and resistance form series impedance whereas the capacitance and conductance form the ...Consider a TEM transmission line aligned along the \(z\) axis. The phasor form of the Telegrapher's Equations (Section 3.5) relate the potential phasor \(\widetilde{V}(z)\) and the current phasor \(\widetilde{I}(z)\) to each other and to the lumped-element model equivalent circuit parameters \(R'\), \(G'\), \(C'\), and \(L'\). ... (\widetilde ...Lossy Transmission Line Impedance Using the same methods to calculate the impedance for the low-loss line, we arrive at the following line voltage/current v(z) = v+e z(1+ˆ Le 2 z) = v+e z(1+ˆ L(z)) i(z) = v+ Z0 e z(1 ˆ L(z)) Where ˆL(z) is the complex reflection coefficient at position z and the load reflection coefficient is unaltered ...

In general, θ = ( π / 2) ( f / f 0). The right-hand side of Equation (5.6.1) describes the series connection of short- and open-circuited stubs having characteristic impedances of Z 0 / 2 and half the original electrical length. This implies that the resulting transmission line resonators are one-quarter wavelength long at 2 f 0 (i.e., they ...

To begin, consider the transmission line with characteristic impedance Z0 attached to a load with impedance ZL: At the terminals where the transmission line is connected to the load, the overall voltage must be given by: [1] Recall the expressions for the voltage and current on the line (derived on the previous page): [2]Impedance mismatches in a radio-frequency (RF) electrical transmission line cause power loss and reflected energy. Voltage standing wave ratio (VSWR) is a way to measure transmission line imperfections. This tutorial defines VSWR and explains how it is calculated. Finally, an antenna VSWR monitoring system is shown.More specifically, we show in the insert of Figure C.1 a transmission line of length l, propagation constant β and characteristic impedance. Z0. It is ...As the impedance of a transmission line is directly proportional to its length, it can easily be concluded that a distance relay can only operate if fault is occurred within a predetermined distance or length of line. Types of Distance or Impedance Relay. There are mainly two types of distance relay- Definite distance relay. Time distance relay.7.6.4 Impedance of a Transmission Line At l = λ ∕4. When the distance from the input of the transmission line to the load is a multiple of λ∕4 (βl = nπ∕2) and therefore l = nλ∕4 (where n is an integer), the input impedance to the transmission line \( \underline {Z}_{in}(l)\) is :This section will relate the phasors of voltage and current waves through the transmission-line impedance. In equations eq:TLVolt-eq:TLCurr and are the phasors of forward and reflected going voltage waves anywhere on the transmission line (for any ). and are the phasors of forward and reflected current waves anywhere on the transmission line. In this scheme, the load impedance is first transformed to a real-valued impedance using a length \(l_1\) of transmission line. This is accomplished using Equation \ref{m0093_eZ} (quite simple using a numerical search) or using the Smith chart (see "Additional Reading" at the end of this section).Transmission line laws: 1. Source and load impedances should be equal to the characteristic impedance of the line if reflections are to be avoided. 2. Think about the voltages on transmission line conductors before connecting them. 3. Think about the currents on transmission line conductors before connecting them.Using Transmission Lines A transmission line delivers an output signal at a distance from the point of signal input. Any two conductors can make up a transmission line. The signal which is transmitted from one end of the pair to the other end is the voltage between the conductors. Power transmission lines, telephone lines, and waveguides are ...

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When you get behind the wheel of your car or truck and put it in gear, you expect it to move. Take a closer look at vehicle parts diagrams, and you see that the transmission plays a role in making this happen. It’s a complex part with an im...The propagation constant of a sinusoidal electromagnetic wave is a measure of the change undergone by the amplitude and phase of the wave as it propagates in a given direction. The quantity being measured can be the voltage, the current in a circuit, or a field vector such as electric field strength or flux density.The propagation constant itself …The characteristic impedance of a transmission line is the ratio of the amplitude of a single voltage wave to its current wave. Since most transmission lines also have a …If the transmission line is lossy, the characteristic impedance is a complex number given by equation (10). If the transmission line is lossless, the characteristic impedance is a real number. In a lossless transmission line, only purely reactive elements L and C are present and it provides an input impedance that is purely resistive. Fig.1 Transmission line. The distributed-element model applied to a transmission line. In electrical engineering, the distributed-element model or transmission-line model of electrical circuits assumes that the attributes of the circuit (resistance, capacitance, and inductance) are distributed continuously throughout the material of the circuit.This is in contrast to the more common lumped ...The instantaneous impedance of the transmission line or the characteristic impedance is the most important factor affecting the signal quality. If the impedance …The impedance of a transmission line is the square root of the ratio between L and C. Given the line is uniform, L and C increase with line length but their ratio stays the same. That's why the impedance is constant for a uniform line of arbitrary length. Share. Cite. FollowSep 12, 2022 · 3.7: Characteristic Impedance. Characteristic impedance is the ratio of voltage to current for a wave that is propagating in single direction on a transmission line. This is an important parameter in the analysis and design of circuits and systems using transmission lines. In this section, we formally define this parameter and derive an ... Transmission Lines as Impedance Matching Components. We’re now in a good position to introduce transmission line-based impedance matching that we alluded to in the previous sections. As an example, assume that we need to transform Z L = 100 + j50 Ω to 50 Ω. The load impedance Z L is actually the same as the value we used in …Advertisement The three-phase power leaves the generator and enters a transmission substation at the power plant. This substation uses large transformers to convert or "step up" the generator's voltage to extremely high voltages for long-di... ….

The impedance spectra measured with cell B consistently showed a straight line at high frequencies, while that line never appeared with cell A. Randles EEC and Transmission Line Models EIS with a blocked electrode is used as a complement to in operando characterization to investigate PEMFC cathode structure and transport properties.A transmission line is an example of a symmetrical two-port network, so interchanging port one and port two will not change the transmission properties. Transmission line S-parameters are influenced by the characteristic impedance Z c and propagation constant 𝛾. In RF circuits, transmission lines act as connectors.is known as the characteristic impedance of the transmission line. The solutions for the line voltage and line current given by (7.5) and (7.6), respec-tively, represent the superposition of and waves, that is, waves propagating in the positive z-andnegativez-directions,respectively. They are completely analogousThe characteristic impedance is never purely resistive. An imaginary component to the characteristic impedance indicates a lossy line, and every real transmission line is lossy. However, a lossless line is easier to model. If you're doing pen-and-paper calculations, you'll have much less math to do if you are working with a lossless line.I was thinking whether I can use the same formula as for the case of resistors. So, the characteristic impedance of two parallel transmission lines will be as shown below and electrical length is the same, theta: Ztotal = Z1 ∗Z2 Z1 + Z2 Z t o t a l = Z 1 ∗ Z 2 Z 1 + Z 2. Is this correct?line-to-neutral. Set the transmission line impedance to 120. First, leave the load unconnected entirely. Turn on the variac and adjust to 150V line-to-line. Record Yokogawa readings for channels 1 and 2 (sending and receiving ends of the transmission line). Label this test point \open circuit." Turn o the breaker but leave the variac setting ...Nov 10, 2020 · The value for a parallel termination is the characteristic impedance of the termination circuit or transmission line is terminated. Determining series terminating resistor values is not so straightforward. The series terminating resistor is intended to add up to the transmission line impedance when combined with the output impedance of the driver. Resistance and inductance together are called as transmission line impedance. Capacitance and conductance together are called as admittance. Resistance. The resistance offered by the material out of which the transmission lines are made, will be of considerable amount, especially for shorter lines. As the line current increases, the ohmic loss ...Marks 10. A 200 volt (r. m. s) generator having an internal resistance of 200 ohm is feeding a loss-less transmission line. The characteristic impedance and the... View Question. Transmission Lines's Previous Year Questions with solutions of Electromagnetics from GATE ECE subject wise and chapter wise with solutions.3/12/2007 Matching Networks and Transmission Lines 2/7 Jim Stiles The Univ. of Kansas Dept. of EECS 4. the transmission line length A. Recall that maximum power transfer occurred only when these four parameters resulted in the input impedance of the transmission line being equal to the complex conjugate of the source impedance (i.e., … Impedance in transmission line, Transmission Lines 105 where Z 0 is the characteristic impedance of the transmission line. The above ratio is only true for one-way traveling wave, in this case, one that propagates in the +zdirection. For a wave that travels in the negative zdirection, i.e., V(z;t) = f (z+ vt) (11.1.16) , Oct 24, 2011 · Back to Basics: Impedance Matching. Download this article in .PDF format. ) or generator output impedance (Z) drives a load resistance (R) or impedance (Z. Fig 1. Maximum power is transferred from ... , The microstrip line is one of the most popular choices of transmission lines in microwave and RF circuits. They consist of a conductor fabricated on the dielectric substrate of permittivity '𝜀r' with a grounded plane. The dielectric material and the air above the microstrip makes it a transmission line with the inhomogenous dielectric ..., , Find the input impedance if the load impedance is , and the electrical length of the line is . Since the load impedance is a short circuit, and the angle is the equation simplifies to . When we find the input impedance, we can replace the transmission line and the load, as shown in Figure fig:IITRLineEqCirc ., Characteristic impedance: This is the impedance of an isolated transmission line. In other words, this is the transmission line impedance when it is …, Marks 10. A 200 volt (r. m. s) generator having an internal resistance of 200 ohm is feeding a loss-less transmission line. The characteristic impedance and the... View Question. Transmission Lines's Previous Year Questions with solutions of Electromagnetics from GATE ECE subject wise and chapter wise with solutions., The delta matching system matches a high-impedance transmission line to a lower impedance antenna by connecting the line to the driven element in two places spaced a fraction of a wavelength each side of element center. It's called a delta match because when connected this way, the feedline and antenna look like the Greek letter delta. ..., Transmission Line Applications- Impedance Matching I One of the most crucial considerations in transmission lines is the impedance matching between the source, line and the load. Mismatch between these impedances result in reflections, which reduce power delivered to the load I Suppose a line of characteristic impedance Z 0 is terminated with ..., a) The termination impedance. b) The center conductor resistivity. c) Dielectrics in the line. d) The termination impedance. 2. A transmission line has a capacitance of 25 pF / ft. and an inductance of 0.15 mH / ft. Determine the characteristic impedance of the line., The coaxial cable, along with the balanced two-wire, is the most common type of transmission line used in RF communications. This calculator helps you calculate the characteristic impedance of a coaxial cable given its dimensions. This will also provide the time delay the cable provides for a signal and also the capacitance and inductance per ..., As discussed in previous articles, the four main variables that determine the impedance of a transmission line on a surface layer include: Height of the trace above the plane over which it travels. The width of the trace. The thickness of the trace. The insulating material used to support the trace. Once the above four variables are known, it ..., A: The input impedance ! HO: Transmission Line Input Impedance Q: You said the purpose of the transmission line is to transfer E.M. energy from the source to the load. Exactly how much power is flowing in the transmission line, and how much is delivered to the load? A: HO: Power Flow and Return Loss Note that we can specify a load with:, The impedance of a transmission line is the square root of the ratio between L and C. Given the line is uniform, L and C increase with line length but their ratio stays the same. That's why the impedance is constant for a uniform line of arbitrary length. Share. Cite. Follow, The goal in exploring design space is to find a combination of parameter values that optimizes some feature, while maintaining the target impedance. The challenge for fine line analysis is that the aspect ratio of trace thickness to line width can exceed 1, which means approximations are not suitable for analysis., In many cases, there is a need to use the same circuit to match a broad range of load impedance and thus simplify the circuit design. This issue was addressed by the stepped transmission line, where multiple, serially placed, quarter-wave dielectric slugs are used to vary a transmission line's characteristic impedance. By controlling the ..., Large disturbances like fault in a transmission line are a concern which needs to be disconnected as quickly as possible in order to restore the transient stability. ... Seyedi H (2015) High impedance fault protection in transmission lines using a WPT-based algorithm. Electr Power Energy Syst 67:537–545. Google Scholar Ray P, Panigrahi BK ..., Transmission Line Impedance, Z 0 • For an infinitely long line, the voltage/current ratio is Z 0 • From time-harmonic transmission line eqs. (3) and (4) 8 ( ) ( ) (Ω) + + 0 = = G j C R j L I x V x Z ω ω • Driving a line terminated by Z 0 is the same as driving an infinitely long line [Dally], Impedance calculations of transmission line and load. Z L =Z o ((1+ρ)/(1-ρ)) TDR impedance measurements can be displayed with volts, ohms, or ρ on the vertical magnitude scale and with time on the horizontal axis. Check the TDR results given below with a variety of impedance and terminations., This page titled 3.9: Lossless and Low-Loss Transmission Lines is shared under a CC BY-SA 4.0 license and was authored, remixed, and/or curated by Steven W. Ellingson (Virginia Tech Libraries' Open Education Initiative) via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request., The cross section of a coaxial line is shown in Figure 2.9.1 2.9. 1 (a) and it has two concentric conductors with the inner conductor having an outer radius of a a and the inside of the outer conductor with a radius b b. The fields between the conductors can be solved by expressing the field relations in cylindrical coordinates., One of the main considerations when routing transmission lines is to control the impedance of the line by using a specific trace width for the line. If the impedance is not matched along the length of the line, it will create signal reflections and potentially disrupt the signal, leading to corruptions of the data being sent., 3.3.4 Input Impedance of a Lossless Line. The impedance looking into a lossless line varies with position, as the forward- and backward-traveling waves combine to yield position-dependent total voltage and current. At a distance ℓ from the load (i.e., z = − ℓ ), the input impedance seen looking toward the load is., Unfortunately for practice, such waves cannot propagate in every transmission line. To show this, let us have a look at the two last lines of Eqs. (100). For the TEM waves (Ez = 0, Hz = 0, kz = k), they are reduced to merely. ∇t × Et = 0, ∇t × Ht = 0, ∇t ⋅ Et = 0, ∇t ⋅ Ht = 0. Within the coarse-grain description of the conducting ..., The characteristic impedance or surge impedance (usually written Z 0) of a uniform transmission line is the ratio of the amplitudes of voltage and current of a single wave propagating along the line; that is, a wave travelling in one direction in the absence of reflections in the other direction., Oct 24, 2011 · Back to Basics: Impedance Matching. Download this article in .PDF format. ) or generator output impedance (Z) drives a load resistance (R) or impedance (Z. Fig 1. Maximum power is transferred from ... , Transmission Line Impedance, Z 0 • For an infinitely long line, the voltage/current ratio is Z 0 • From time-harmonic transmission line eqs. (3) and (4) 8 ( ) ( ) (Ω) + + 0 = = G j C R j L I x V x Z ω ω • Driving a line terminated by Z 0 is the same as driving an infinitely long line [Dally], voltage across it, is referred to as the transmission line, even though it is really only half of the structure. There are two ways to model a lossless transmission line. One method defines the transmission line in terms of characteristic impedance (Z0) and time delay (td) and the other method defines the transmission line in terms of total, In Part 1 of this article, I reviewed the four basic types of PCB transmission lines and the various equations used for calculating the impedance associated with those lines. Part 1 also discussed why those equations only tell part of the story, and why there are other influencers including 2D field solvers; knowing the glass-to-resin ratio and knowing the frequency at which transmission lines ..., You may have seen headlines recently that “patients without symptoms” aren’t driving the spread of the coronavirus. That would seem to suggest that all our measures about masks and distancing are useless—but that’s a misunderstanding of the..., b. Series Impedance -accounts for series voltage drops Resistive Inductive reactance c. Shunt Capacitance -accounts for Line-Charging Currents d. Shunt Conductance -accounts for V2G losses due to leakage currents between conductors or between conductors and ground. School of Engineering 14, 1)when the load end is open circuited. 2)when the load end is short-circuited. 3)when the line is not terminated in its characteristic impedance. When the line is either open or short circuited, then there is not resistance at the receiving end to absorb all the power transmitted from the source end., Advertisement The three-phase power leaves the generator and enters a transmission substation at the power plant. This substation uses large transformers to convert or "step up" the generator's voltage to extremely high voltages for long-di...