Adaptive Coordinated Protection for DC Microgrids With Lunar Surface Power Applications

The future of deep space exploration is becoming increasingly dependent on a reliable and resilient electric power system (EPS) to support several subsystems including life support, electric propulsion, autonomous rovers, and more. The planned growth of NASA’s Artemis base camp will present new challenges in the operation and control of the expanding EPS. In particular, improved fault detection and isolation methods are needed to protect the microgrid from faults as it undergoes expansion and modifications given the limitations and constraints of a space-based power system. This paper proposes a pragmatic technique for achieving coordinated zonal protection against direct current (DC) line-to-ground faults with autonomous adaptive tuning for topological and operational changes to the EPS. Here a dynamic method is developed to tune circuit breaker settings based on the given system topology, generation capacity, and expected load. The proposed adaptive coordinated protection approach is demonstrated using real-time simulation and hardware-in-the-loop (HIL) experiments to evaluate its effectiveness in achieving zonal fault isolation.