Design and Implementation of a Soft Switched Inverter Based 400 Hz Power Supply

Abstract

In this dissertation, the suitability of Resonant DC Link Inverter (RDCLI) for a 400 Hz Power Supply usually applicable for Aircrafts/ Ships etc. is investigated. Aircrafts and such equipment usually operate at 400 Hz (8 times the standard frequency) primarily for the purpose of reducing the sizes of the connected loads. Since usually available generators are designed for 50 Hz, power converters and controls come into force for designing a 400 Hz supply. Basically we have two options (Hard switched and Soft-Switched) while adopting AC-DC-AC conversion. Soft-switched inverters will score over this specific application for constructing a 400 Hz waveform usual PWM frequency required would be at least 4 kHz. For medium power applications (100 kVA) operating at 4 kHz could be a difficult task for a hard-switched inverter. However, Soft-Switching Inverter in the form of RDCLI is a better option as it would provide a huge current regulator bandwidth. Furthermore, switching losses would be virtually zero that would facilitate improving the efficiency of the power supply.