Capacitor fundamentals

In this review of capacitor fundamentals, the author attempts to clarify the modes of operation of the broad spectrum of capacitors, including paper/polymeric films, electrolytics, and ceramics. How each class of capacitor performs in both low- and high-power electronics is discussed in detail, with emphasis upon delineating those factors affecting life, reliability, maintainability, and environmental compatibility of systems in which the capacitor is a required element. Diagnostic measurement techniques for quality assessment, noninvasive life determination, and system continuity of performance under component aging are analyzed and compared. Particular emphasis is given to the influence of the mode of operation of the capacitor upon life and reliability, including energy discharge, low- and high-frequency filtering in AC+DC systems, AC resonant inverter, and switch-mode power supply use, along with transient pulse filtering applications. Practical factors as delineated by manufacturers in the field are discussed in depth