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Illustration of the Ferranti effect; addition of voltages across the line inductance. In electrical engineering, the Ferranti effect is the increase in voltage occurring at the receiving end of a very long (> 200 km) AC electric power transmission line, relative to the voltage at the sending end, when the load is very small, or no load is connected.
Transmission lines are subject to thermal limits (simple megawatt limits on flow), as well as voltage and electrical stability constraints. The simulator must calculate the flows in the AC network that result from any given combination of unit commitment and generator megawatt dispatch, and ensure that AC line flows are within both the thermal ...
The slack bus provides or absorbs active and reactive power to and from the transmission line to provide for losses, since these variables are unknown until the final solution is established. The slack bus is the only bus for which the system reference phase angle is defined. From this, the various angular differences can be calculated in the ...
The resistance and conductance contribute to the loss in a transmission line. The total loss of power in a transmission line is often specified in decibels per metre (dB/m), and usually depends on the frequency of the signal. The manufacturer often supplies a chart showing the loss in dB/m at a range of frequencies.
The analysis of lossless lines provides an accurate approximation for real transmission lines that simplifies the mathematics considered in modeling transmission lines. A lossless line is defined as a transmission line that has no line resistance and no dielectric loss. This would imply that the conductors act like perfect conductors and the ...
a double circuit transmission line; two generators; a bus bar. Non-credible (also called "out-of-range") contingencies are not used in planning, as they are rare and their effects are hard to predict, for example, failures of: [4] an entire electrical substation; a transmission tower that carries more than two lines.
Multiple empirical formulae exist that relate the loss factor to the load factor (Dickert et al. in 2009 listed nine [5]). Similarly, the ratio between the average and the peak current is called form coefficient k [ 6 ] or peak responsibility factor k , [ 7 ] its typical value is between 0.2 to 0.8 for distribution networks and 0.8 to 0.95 for ...
In telecommunications, return loss is a measure in relative terms of the power of the signal reflected by a discontinuity in a transmission line or optical fiber. This discontinuity can be caused by a mismatch between the termination or load connected to the line and the characteristic impedance of the line.