Space Microgrids

At CROM, this area comprises three exciting topics which are currently investigated by our researchers together with our collaborators:

Microgrid technologies for nano and cubesats

The electric power systems (EPSs) are of a paramount importance in satellites. These systems are responsible for power generation, storage, delivery, and conditioning. A failure in an EPS may hinder all the aforementioned functionalities, which consequently, leads to a failure of the whole space mission. There are many technologies available in both industry and literature of EPSs, where each has its own fault tolerance capabilities. On the other hand, the efficiency of the EPS is an important factor, which promotes having higher power reserve; thus, feeding the payloads at all needed times. In this paper, the EPS for Satellites-based microgrids are reviewed with more focus on their energy generation and storage, including their protection schemes. Moreover, sizing guidelines for the energy generation and storage systems are also provided. In this paper we review

Closed ecosystems – microgrids for biological architectures

One of the main challenges of human space exploration is the development of artificial ecosystems, which can be used as Life Support Systems (LSSs) to enable long duration human space missions. In an open LSS, no food generation or waste treatment is provided in space and supply from earth is necessary. Closed ecological systems (CESs) are ecosystems without any matter exchange with outside environment. CESs are necessary for long-term manned space missions, which aims minimizing support from Earth. They are composed of several specific compartments that together reproduce the main functionalities of an ecological system in continuous mode of operation and under controlled conditions.

By considering the approximate metabolic consumables and hygiene water, as well as the number of crewmembers, a huge mass would be required to be transported from earth, which brings the necessity of a regenerative or closed LSS.

MELiSSA (Micro-Ecological Life Support System Alternative) is an EU research project aiming to develop a closed bio-regenerative LSS for long-term manned space missions minimizing support from Earth. MELiSSA has been fostered by the European Space Agency (ESA) since 1989 and it is focused on developing a CES composed of six specific microbiological compartments that reproduce the main functionalities of an ecological system in continuous mode of operation and under controlled conditions.The MELiSSA pilot plant (MPP) was built at Universitat Autònoma de Barcelona (UAB) in 2009, once a certain knowledge was accumulated about the compartments, in order to integrate them in a testing facility with high quality standards.

Space microgrids for future manned lunnar base

The present study analyses the design of the power system of a manned lunar base, in Shackleton crater, using well-established terrestrial technologies deriving from DC microgrids with increased fault-tolerance needs. Expected luminance data from 2020 is used in order to select the ideal base location in terms of mean annual solar Irradiance, according to which, the sizing of the power generation and storage units is performed. The proposed grid topology is meshed in order to satisfy the high reliability requirements of a manned space mission and, at the same time, to reduce the mass/ volume budgets of the mission. The load profile is constructed using a set of notional loads. Furthermore, a novel solar array configuration is proposed under the scope of maximizing the energy production under the specific irradiance of the base siting. After preliminary sizing is performed, a series of microgrid-related technologies is suggested, covering all levels of grid design, control and protection.