To design a Power Conditioning and Distribution Unit (PCDU) for EO missions based on GaN semiconductors, with overall performance improvement, mass, volume and non-recurrent (NRE) cost reduction

 

Gan technology for power applications is becoming mature these days. Gan switches can operate at higher frequencies and with the same level of efficiency as Si ones, with overall mass and volume PCDU benefits.

 

Typical Earth Observation (EO) active instruments like Synthetic Aperture Radar, scatterometers or altimeters, and Laser Detection And Ranging, transmit high energy pulses in short periods of time. These pulses could be easily handled with gan based converters and the rest of the platform would not be affected at all, improving the electrical noise quietness.

 

Since the max power level provided by a gan devices is limited compared to Si ones, a technical workaround is to implement multi-phase topologies that split the power processing into multiple parallel phases.

 

Another key point is the possible improvement of PCDU dynamic capabilities. With GaN, a 1mHz switching frequency and 100 kHz bandwidth could be easily reached, meaning that DC/DC converters could react much faster and keep the power quality even with high frequency pulsating payloads.

 

A GaN based Maximum Power Point Tracker (MPPT) could potentially achieve a similar cost to a simpler Direct Energy Transfer (DET) option, but with higher flexibility to standardize the PCDU for application in various missions.

 

The tasks involved are:

- Consolidate the specifications of the target PCDU for an EO mission

- Revisit all conversion PCDU modules to identify which components can be substituted by GaN semiconductors

- Identify GaN components to be used at PCDU level

- Perform the conceptual design of the whole PCDU to trade off mass, volume, dissipation, dynamic performance and manufacturing simplicity

- Draft the detail design of the conversion and distribution modules

- Build and test a breadboard of the conversion and distribution modules

- Develop the thermal concept of the PCDU