Title :
Zero-voltage detection in thyristor and triac convertors
Author :
Davis, R.M. ; Downing, B.R.
Author_Institution :
University of Nottingham, Department of Electrical & Electronic Engineering, Nottingham, UK
Abstract :
A sensitive voltage (zero-crossing) detector for a thyristor/triac is described. An optically coupled isolator (o.c.i.) has its light-emitting diode supplied from a constant-current source, and a pair of transistors bypass this current when there is sufficient voltage across the power device. The pulse output of the o.c.i. is sufficiently sharp to drive the logic circuit directly.
Keywords :
detectors; light emitting diodes; optoelectronic devices; power convertors; thyristor applications; LED; logic circuit; optically coupled isolator; thyristor; triac convertors; zero voltage detection;
Journal_Title :
Electronics Letters
DOI :
10.1049/el:19730194
