Contactless Energy Transfer System For Satellite Applications

Abstract

The number of satellites launched every year is ever-increasing. Satellites generate energy through solar panels, transferring it to the satellite hub using Slip Ring Assemblys (SRAs). However, SRAs suffer from limited lifetime and operating voltages. Therefore, this research investigates a Contactless Energy Transfer (CET) system for the satellite to eliminate these problems. The system consists of an input source, inverter, Alternating Current (AC)-link and rectifier. A single diode model is introduced for the solar panel input source to model its behaviour. After a brief comparison, the Inductive Power Transfer (IPT) method is favoured over the Capacitive Power Transfer (CPT) method. As a result, the AC-link includes a transformer to obtain the contactless energy transfer. The Single Active Bridge (SAB) topology is chosen after comparing the characteristics of the SAB and Dual Active Bridge (DAB) topologies. Afterwards, two SAB converters, the Single Active Bridge with Output Inductor (SABL) and LLC converter, are compared before choosing the LLC converter. With the CET system design completed, the design procedure for the LLC converter is presented, resulting in transformer requirements. A coaxial solenoid transformer design procedure where the inductance and losses are modelled is used to create a prototype transformer. The models are validated using Finite Element Method Magnetics (FEMM). The designed transformer met the inductance requirement. However, the losses were too significant to meet the overall CET system efficiency requirement.