FPD medium power inverter


FPD medium power inverters are power and electronics devices made with the MOSFET transistor technique, transforming direct voltage to the sinusoidal voltage variables with values in the range of 3x400V and frequency of 50/60Hz. They have built-in transformers matching voltage and providing galvanic isolation between the input direct voltage and the output. Due to the option of parallel operation it is possible to connect outputs of several inverters to increase power or build of systems operating in redundancy.

The inverters, depending on their versions, may be equipped with an input rectifier, their own battery, the output of the power source switch with the service bypass. They also cooperate with external contactless STS switches.


  • Module construction
  • Parallel operation of power units
  • Resistance to overload and short-circuit
  • Output voltage with high stability and small strains
  • Convenient maintenance
  • High reliability
  • High power density to the dimensions
  • Synchronization of the output voltage with the mains
  • Standard equipment in the contactor circuit switching output voltage



  • STS – thyristor with service bypass
  • PD, ZP – own rectifier network type (next page)
  • BTL – maintenance by DC line
  • BTW – maintenance by its own battery
  • TrO – additional transformer in the bypass circuit
  • SZR – contractor switch at the input side of the network



  • A. Inverter
  • B. Inverter + STS
  • C. Diode rectifier + inverter + STS
  • D. Transistor rectifier + inverter + STS E. Rectifier transistor + inverter + STS + transformer in the bypass circuit