PLEGPAY: A Plasma Contactor Experiment on the International Space Station

PLEGPAY (PLasma contactor Electrical Grounding PAYload) is an experiment for the in-flight validation of the plasma contactor as an active device for the prevention/control of electrostatic charging on large space structures orbiting in LEO and for addressing scientific investigations on plasma/spacecraft interactions. The validation of the plasma contactor technology will be carried out also in view of possible future applications/utilizations on board the ISS where "Tethered Systems" are deployed from the ISS, with the purpose of performing electro-dynamic experiments or to pursue technology applications (e.g. power generation or "re-boosting"). PLEGPAY has been selected by ESA for accommodation on the EuTEF, the European Technology Exposure Facility, developed by. Carlo Gavazzi Space under ESA contract to provide the logistics support for different experiments during the ISS early utilization. The development/qualification of PLEGPAY is currently underway under ASI contract and ESA co-ordination. The plasma contactor device is directly derived from the cathode/neutralizer technology developed by LABEN/Proel for Electric Propulsion applications [1], [2]. In this field LABEN/Proel has developed and qualified cathodes/neutralizers for electron currents in the range 0.3 – 5 A. Recently the development of a 20 A device has been started. In the paper a detailed description of the PLEGPAY assemblies, as well as of the foreseen in-flight experiments, is addressed. An overview of the mass, envelope and power budgets related to the payload is also presented. PLEGPAY is expected to be integrated on the EuTEF by 2003. The launch is foreseen at the beginning of year 2005.