Electric propulsion is gaining popularity in space industry. This type of propulsion is replacing chemical propulsion for different maneuvers. But it deeply modifies the ambient plasma that surrounds the satellites and can affect the operation of satellites. Modelling the interactions arising from electric propulsion is then critical. In the frame of SPIS, a simulation software designed to simulate plasma-spacecraft interactions, European Space Agency (ESA) started the AISEPS project which aimed at modelling these interactions. Here, we report the development of new features for SPIS during the last phase of the AISEPS project, how they operate and were tested. Using these developments, a complete spacecraft is modelled and the variation of its floating potential resulting from its solar array rotation is reproduced.