ECE CHAPTER 3 - Energy-Storage Elements - Inductors and...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Energy-Storage Elements - Inductors and capacitors: can store energy and later return it to the circuit - Passive elements - Capacitance: the circuit property that accounts for energy stored in electric fields - Inductance: accounts for energy stored in magnetic fields Capacitance - Constructed by separating two sheets of conductor by a thin layer of insulating material - A Dielectric: the insulating material between the plates - The stored charge is equal to the capacitance multiplied by the voltage between the plates ( q = Cv ) - Units: farads (F) or coulombs per volt (C/V) - The charge q is the net charge on the plate corresponding to the positive reference for v - i = dq / dt = d / dt ( Cv ) = C ( dv / dt ) - A capacitor appears to be an open circuit for a steady dc voltage - The current reference direction points into the positive reference polarity - q(t) = (int t o => t) i(t)dt +q(t o ) - v(t) = 1/C (int t o => t) i(t)dt + v(t o ) Stored Energy - w(t) = ½Cv 2 (t) = ½v(t)q(t) = q 2 (t)/2C Capacitance in Parallel
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 02/20/2012 for the course ECE 083 taught by Professor Best during the Spring '08 term at Lehigh University .

Page1 / 2

ECE CHAPTER 3 - Energy-Storage Elements - Inductors and...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online