Having played a central role in the modernization of power electronics in the 1960s, large capacity thyristors are now handling higher voltages and currents. In the 1980s, it evolved from a reverse blocking thyristor without self-turn off function to a GTO (Gate Turn off) thyristor that switches from an ON to an OFF state by applying a negative gate signal even in a DC circuit. Furthermore, the GCT (Gate Commutated Turn off) thyristor was developed, inheriting the basic structure of the GTO thyristor but significantly reducing impedance of the gate to achieve high speed operation and high turn off performance.


The SGCT (Symmetrical Gate Commutated Turn-off) thyristor unit is a GCT thyristor with reverse voltage blocking capability and an optimally designed gate driver integrated into the unit, thus maximizing the performance of SGCT thyristors and reducing system design load.

  • High withstand voltage and reverse blocking types: Voltage rating: forward/6,500V, reverse/6,500V
  • Reduces power loss with low on-voltage, which is a characteristic of thyristors.
  • Optimal for high-voltage circuit breaker, current source inverter applications.


    • High voltage inverter
    • Frequency changers
    • SVG (Static Var Generator)
    • BTB (Back-to-Back)
    • High-voltage circuit breakers

    List by function

    機種 Rated current Rated voltage
    2.5kV 4.5kV 5.0kV 6.0kV 6.5kV 12kV
    GCT SGCT thyristor unit 400A
    GCT thyristor 6000A
    GTO thyristor 1000A
    Reverse-blocking thyristor 1500A



      Corresponding Products

      HVIGBT Modules