Fast ON/OFF Detection of Silicon-Controlled Rectifiers and Its Influence on Convertor Controllability

The degree of controllability provided by static convertors is mostly determined by the speed and accuracy of information available from the transducers. This paper discusses the effect of providing fast ON/OFF detection of the silicon-controlled rectifier and describes two novel methods of achieving such information. It is concluded that a method based on continuous monitoring of the gate-to- cathode voltage level provides sufficiently reliable and fast ON/OFF information for the purpose of direct digital control of the convertor plant.