Introduction To Thyristor

Introduction to thyristor

Silicon Controlled Rectifier (SCR), also known as thyristor, is a high-power electrical component. It has the advantages of small size, high efficiency, and long service life. In automatic control systems, it can be used as a high-power driver to control high-power devices with low-power controls. It has been widely used in AC and DC motor speed control systems, power regulation systems, and servo systems.

There are two types of thyristor: unidirectional thyristor and bidirectional thyristor. Bidirectional thyristor, also known as three-terminal bidirectional thyristor, abbreviated as TRIAC. Bidirectional thyristor is structurally equivalent to two unidirectional thyristors connected in reverse, and this type of thyristor has bidirectional conduction function. Its on/off state is determined by the control pole G. Adding a positive (or negative) pulse to the control pole G can make it conduct in the forward (or reverse) direction. The advantage of this device is that the control circuit is simple and there is no reverse voltage withstand problem, so it is particularly suitable for use as an AC contactless switch