A thyristor is a power semiconductor device that can control the on and off states of large currents. The advent of thyristors enabled semiconductor devices to transition from the domain of low-current applications to high-current applications, and they have since been widely used in the power electronics industry. Because the on and off states of thyristors can be controlled, they are also known as Silicon Controlled Rectifiers (SCRs). Thyristors are primarily used for rectification, voltage regulation, inversion, and switching. Structurally, thyristors consist of four layers forming three PN junctions, which are functionally equivalent to a combination of PNP and NPN transistors. Derivative devices of thyristors include the Fast Switching Thyristor (FST), TRIAC (Bidirectional Triode Thyristor), Reverse Conducting Thyristor (RCT), and Light Triggered Thyristor (LTT).