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Susceptance
In electrical engineering, susceptance (''B'') is the imaginary part of admittance, where the real part is conductance. The reciprocal of admittance is impedance, where the imaginary part is reactance and the real part is resistance. In SI units, susceptance is measured in siemens. Origin The term was coined by C.P. Steinmetz in a 1894 paper. In some sources Oliver Heaviside is given credit for coining the term, or with introducing the concept under the name ''permittance''. This claim is mistaken according to Steinmetz's biographer. The term ''susceptance'' does not appear anywhere in Heaviside's collected works, and Heaviside used the term ''permittance'' to mean capacitance, not ''susceptance''. Formula The general equation defining admittance is given by Y = G + j B \, where The admittance () is the reciprocal of the impedance (), if the impedance is not zero: Y = \frac = \frac = \left( \frac \right) \left( \frac \right) = \left( \frac \right) + j \left( \frac \r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrical Reactance
In electrical circuits, reactance is the opposition presented to alternating current by inductance or capacitance. Greater reactance gives smaller current for the same applied voltage. Reactance is similar to resistance in this respect, but does not lead to dissipation of electrical energy as heat; instead, energy is momentarily stored in the reactance, and a quarter-cycle later returned to the circuit. Reactance is used to compute amplitude and phase changes of sinusoidal alternating current going through a circuit element. Like resistance, reactance is measured in ohms, with positive values indicating ''inductive'' reactance and negative indicating ''capacitive'' reactance. It is denoted by the symbol X. An ideal resistor has zero reactance, whereas ideal inductors and capacitors have zero resistance. As frequency increases, inductive reactance increases and capacitive reactance decreases. Comparison to resistance Reactance is similar to resistance in that larger reactan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |