IGCT Integrated Gate Commutated Thyristors are a new type of power semiconductor switching device developed for medium voltage frequency converters and used in giant power electronic complete sets of equipment (Integrated Gate Commutated Thyristors=Gate Commutated Thyristors+Gate Units). Proposed by ABB in 1997. IGCT enables the converter device to

Significant progress has been made in power, reliability, switching speed, efficiency, cost, weight, and volume, bringing new leaps to power electronics equipment. IGCT integrates GTO chips with anti parallel diodes and gate driver circuits, and then connects them with the gate driver in a low inductance manner on the periphery. It combines the advantages of stable turn off capability of transistors and low on state loss of thyristors, and exhibits the performance of thyristors during the conduction stage and the characteristics of transistors during the turn off stage. IGCT has the characteristics of high current, high blocking voltage, high switching frequency, high reliability, compact structure, and low conduction loss. Moreover, it has low manufacturing cost and high yield, and has been widely used in power system grid devices (100MVA) and medium power industrial drive devices (5MW). IGCT has been successfully applied in the field of medium voltage frequency converters for 11 years (until 2009). Due to its high-speed switching capability, IGCT does not require buffer circuits, requiring fewer power components and greatly improving operational reliability.

IGCT combines the high-speed switching characteristics of IGBT (Insulated Gate Bipolar Transistor) with the high blocking voltage and low conduction loss characteristics of GTO (Gate Turn Off Thyristor). Generally, the trigger signal is transmitted to the IGCT unit through optical fiber. In the phase module of the active rectifier unit of ACS6000, each phase module is composed of IGCT, diode, and clamp capacitor, and is powered by an independent gate power supply unit GUSP.