Thyristor

in electrical technology is a controllable semi-conductor element, as opposed to a diode, which cannot be controlled. Thyristors are used in frequency converter technology for rectifiers and current inverters for the operation of induction furnaces. High-performance thyristors are water-cooled, and can therefore be very small in size. Thyristors have also been developed in air-cooled versions, although these require relatively clean cooling air at a maximum of 33 °C.