Design and development of a smartphone based picosatellite : power management system
Koh, Yong Jing
Date of Issue2016
School of Electrical and Electronic Engineering
Satellite Engineering Centre
The objective of the project is to develop a reliable power management system for the VELOX-PIV picosatellite. A picosatellite is a satellite that has a small weight (typically less than 1kg) and small dimension (typically less than 10cmx10cmx10cm). The satellite research centre of NTU has previously completed 3 picosatellites named VELOX-PI, VELOX-PII and VELOX-PIII. In this project, the VELOX-PIV will be developed with the objective of putting a smart phone into the satellite to provide functionalities such as camera, inertial measurement system and data processing etc. The power management system consists of 3 main modules namely, the solar array module, battery management module and power distribution module. The GaAs solar panels with 2.4W peak power are chosen to be used in the solar array module. The battery management module is designed to control the battery voltage and temperature. Battery overcharge protection, discharge protection and temperature control functions have been implemented to ensure the battery voltage and temperature are maintained at the desired level. 4 latched output channels have been developed in the power distribution module to ensure overcurrent protection. Rebooting functions have been implemented to ensure automatic rebooting on overcurrent trip. Maximum power point tracking algorithm is implemented to ensure maximum tracking efficiency. In addition, an interconnection module is designed to connect the power management system with the other subsystems of VELOX-PIV. The power management system has been successfully integrated with the other subsystems in the satellite and testing has been conducted on this flat satellite model. The power management system has also been successfully tested with the ground station system. The developed power management system is able to send the housekeeping data of the satellite to the ground station system for monitoring and it is also able to execute the commands given by the ground station.
Final Year Project (FYP)
Nanyang Technological University