A 400 Hz, 100 kVA, Digitally Controlled UPS for Airport Installations

The paper describes the analysis, design and prototyping in reduced scale of a digitally controlled inverter for uninterruptible power supply (UPS) applications. The converter is rated for 100 kVA nominal power and 400 Hz, three-phase, 220 V sinusoidal output voltage. The final equipment is meant to be installed in airport docks and used as the aircraft's electrical power supply during refuelling and loading operations. It will be manufactured with different power ratings ranging from 30 to 300 kVA. The power converter and digital control circuits are devised to provide rated voltage and frequency with a fairly low output impedance, so as to keep the voltage total harmonic distortion (THD) small even in the presence of highly distorting loads. Simulation results for the rated converter and experimental results from a scaled (5 kVA) prototype are given, which illustrate the expected converter performance.