Abstract :
Since the General Electric Co. of America produced the first thyristor in 1957, it has become widely used because of its advantages over its gaseous equivalent, the grid-controlled mercury-arc valve. The thyristor has the ability to control large power flows; thus there is a predominance of power engineers among the users of the device. Understandably, many consider the thyristor as a `blackbox¿ with the properties of a controllable switch. It is hoped that this article will introduce some of the complexities and subtleties of the thyristor, and perhaps stimulate interest in the machinations within the device.
