The development of innovative flexible power systems (e.g. DC grids, zonal distributions, hierarchical controlled grids, microgrids) involves the introduction of new active devices. The control and management of these devices is ensured only in presence of a distributed and performing data communication network. To properly operate the grid, each device must be thus the active interface to the other controlled systems. The test of these complex controlled configurations represents a challenge to be faced. In this regard, Hardware-In-the-Loop platforms are effective in the testing activity. The paper proposes a methodology to model a zonal DC system, whose simulation is performed in RTAI (Real Time Application Interface), an open source real-time operating system. The correct functioning of open source system is proven by comparing experimental-live transients and HIL simulation outputs. Such a verification testifies the potentiality of the described approach.
