Thyristor switching modules CTU02 are designed for dynamic and hybrid PFC based on three-phase capacitors. CTU02 modules have special semiconductor switcher in each phase. Together with controllers FCR and GCR range they can reach the best possible speed of reconnection up to 25 operations per 1 second. Special construction of the module solves voltage discharging problem so the three-phase capacitor can be switched again immediately after disconnection without prior discharging. Switching is realized within 10 ms from receiving the signal from PF controller. .


ctu fceThyristor switching modules CTU are constructed for switching of LC circuits with prevailing capacitive part (detuned compensation stages). Advantage of CTU modules comparing to the classic contactor switching of capacitor stages is immediate capacitor connection without its previous discharging. This is possible thanks to special construction which assures that capacitor is ready for another connection immediately after its previous disconnection. Switching of capacitor is realized at the moment when the difference between the capacitor voltage and system voltage before the switching element is equal to zero. From this feature comes another important advantage and this is significant current surges reduction. Current surges are causing disturbances which can affect proper running of electronic devices and can severely damage and even destroy them. Further more, lifetime of capacitors is increased, because only nominal current flows through the circuit. For the protection of power switching element against current peaks (di/dt) it is necessary to connect in the series with module also inrush inductor.

Temperature protection

Inside the CTU02 module aluminum cooler is installed temperature sensor which is used for protection of semiconductors against damage by high temperature. Temperature level is set on 80°C.

Forced ventilation

CTU02-400-50 and CTU02-400-72 have a ventilator for forced ventilation of aluminum coller. The ventilator is started automatically when temperature of CTU02 rise over the defined level.


Main features

  • Designed for three-phase capacitors
  • Switching element in each phase
  • Switching speed up to 25 operations / 1 s
  • Control voltage 24 VDC or 230 VAC
  • Operation status signalization
  • Ready for dynamic and hybrid PFC