Ideal and Real Capacitors: How their Behaviour Affect Energy Efficiencies

• Type: Chapter or Part of a Book
• Date: 2012

Authors

Paulo Simeão Carvalho (Author) FCUP; Adriano Sampaio e Sousa (Author) FCUP

Book

Title: Encyclopedia of Electrochemistry Research

Pages: 41-57

Scientific classification

FOS: Natural sciences > Physical sciences

CORDIS: Physical sciences > Physics

Other information

Abstract (EN): Capacitors are generally considered “old fashioned” topics for scientific discussion. Classical treatment of these components tends to represent them as ideal components and forget their real behavior. Real capacitors are built by dielectrics with a finite resistance that result in a leakage electric current that affects the capacitor efficiency. In this work, we will focus our attention on how efficiency can be calculated and measured, giving alternative ways for the calculus of the time constant and the energies stored and supplied during charge and discharge processes in DC circuits, representing the electric power as a function of time in ideal and real capacitors. This will help to understand the difference between an ideal capacitor and a real one, and show why the efficiency of a real capacitor is always less than 50 %. Discussion about real capacitors will involve both DC circuits and AC circuits.

Language: English

Type (Professor's evaluation): Scientific