Advanced power converters for More Electric Aircraft applications

A DC-DC converter and a DC-AC inverter are under development for More Electric Aircraft (MEA) use. They are both highly compact and are designed to operate from 270 VDC input power and produce output power that meets requirements for fighter aircraft, including compliance with MIL-STD-704E and MIL-STD-461D guidelines. Both units are designed to be cooled with Poly Alpha Olefin (PAO) at 30/spl deg/C maximum inlet temperature and to operate for at least 30 s after a loss of coolant flow before shutting down. Both units are designed to withstand 20 Gs shock loadings and random vibration loadings up to 0.04 G/sub rms//sup 2//Hz for the DC-DC converter and 0.36 G/sub rms//sup 2//Hz for the DC-AC inverter. The reliability goal is 25000 hour mean time between failures (MTBF). Both units incorporate under/overvoltage, short circuit, and over temperature protection. The DC-AC inverter also has over/under frequency, DC content, waveform distortion, and zero voltage content protection. The paper describes the design of both units and the resulting performance. The results of tests on both units are summarized.