Artistic depiction of what a sustainable micronetwork for a lunar base camp might look like. Sandia National Laboratories engineers are working with NASA to design a system controller for the microgrid. Credit: Illustration by Eric Lundin

Sandia National Laboratories is well known for designing reliable and sustainable micronetworks for military bases and vital urban services. Sandia researchers are now working with NASA to design one for the moon.


This is not the first time Sandia has partnered with NASA to power equipment on the moon. In fact, Sandhya provided technical guidance for the radioisotope thermoelectric generators that powered the lunar experiments set up by many of Apollo’s missions.

NASA’s plan for the concept of the Artemis lunar base is for it to serve as a technological test site for possible human exploration of Mars, said Jack Flicker, an electrical engineer in Sandia. The base camp concept consists of a housing unit – complete with space for up to four astronauts – as well as the potential for separate extraction and refueling, called on-site resource use facilities. Artemis’ early missions will include a short stay at base camp to increase to two months at a time.

Mining and processing facilities could produce rocket fuel, water, oxygen and other materials needed for long-term exploration of the lunar surface, while reducing the need for supplies from Earth. The facility will be located away from the base camp – so other scientific and technological activities carried out there will not be disrupted – but the power grid for the two units will be connected during emergencies for resilience and strength, Flicker added.

Part of the Sandia team, which includes Lee Rashkin and Dave Wilson, is designing an electrical system controller for the mining network’s microgrid. NASA is designing the controller of the electrical system for the apartment building, as the system will be very similar to the electrical system of direct current of the International Space Station, said Flicker. Flicker and his team are developing a system that will connect the two micro-networks and study the flow of power and operation between the two micro-networks.

“There are some very important differences between something like an ISS-type micronetwork and something that has a lunar basis,” Flicker said. “One of these differences is the geographical size, which can be problematic, especially when working at low DC voltages. Another is that when you start expanding these systems, there will be many more power electronics, as well as many more distributed energy resources that will exist throughout the base. Sandia has been looking for micro-networks with many distributed energy resources for a long time. “

Distributed energy resources are smaller sources of electricity such as solar panels and wind turbines, while power electronics are devices such as converters that keep electrical systems running within specifications.

Cruise control for the lunar digging center’s electrical system

Rashkin, an electrical engineer, and Wilson, a management engineer, have been designing the electricity control software at the Mining and Processing Center since the early summer of 2021. Wilson compares their controller to cruise control in a standard car because it maintains a steady voltage level. network, despite changing external situations.

The controller must be able to maintain a steady voltage level over several different time scales, from less than a thousandth of a second to the seasons. At the highest level of management software, ranging from minutes to seasons, people can control which solar panels generate energy and which energy-using devices are included, Wilson said. However, at the lowest level, less than a thousandth of a second, the controller must operate quickly and automatically to maintain the outputs at the required levels. They are focused mainly on the average level of control, Rashkin said.

Moon power: Sandia researchers are designing a micronet for a future lunar base

Sandia National Laboratories electrical engineers Rachid Darbali-Zamora, at the front, and Lee Ruskin, are testing an algorithm for the lunar micronetwork controller on hardware setup in the Distributed Energy Technology Laboratory circuit. Credit: Rebecca Gustaf / Sandia National Laboratories

“Our goal is to create a lunar power management system that can effectively keep the system up to standard on all these time scales,” Wilson said. “We have a specialized tool for a secure scalable micro-network and a methodology for designing a control system that analyzes this. The facility also has specialized energy storage emulators that can help us determine the specifications for how much storage energy the base needs and their requirements. ”

Secure Scalable Microgrid Testbed is a unique Sandia research facility that the team will use to fine-tune its management system. They will also use the test site to study issues of energy system controllers and interactions between distributed energy resources, energy storage and power electronics in the DC microarray, which is a scaled-down and simplified presentation of a possible lunar microarray, Rashkin said. Most terrestrial micro-networks and terrestrial electrical networks generally operate on alternating current.

Like a set of high-end trains, the test bench consists of three interconnected DC microarrays with specially built electronics to mimic different power generation systems and devices that use electricity. Power generation systems that can mimic include diesel generators, photovoltaic grilles, energy storage emulators, and power converters. Each of the emulators can be controlled by a computer, and micronetworks can be configured to test an infinite variety of scenarios, Rashkin said. This provides an excellent platform for repetitive experiments with slightly adjusted management software to compare how the system responds, he added.

“The goal here is top-down engineering: first we try to define the control design, come up with energy storage specifications, and then NASA can use those specifications to get ready-to-fly components that meet those specifications.” Said Wilson. “In most cases, people do the opposite, they’ll bring you a battery and tell you to ‘make it work,’ which can degrade micro-network performance.”

Other researchers heavily involved in the development of controllers include Marvin Cook, a computer scientist from Sandia; Wayne Weaver and Rush Robinet III, engineering professors at the University of Michigan; and Joseph Young, chief scientist of OptimoJoe.

Two micro-networks are needed.

The second main focus of Sandia researchers is the development of a system that will connect the micro-networks of the mining facility and the housing units for resilience and strength. There are two main ways to achieve micronet network resilience, Flicker said. One is to have the ability to flexibly direct the power where it is needed. The other is oversize everything to ensure there is enough power, even if a few things fail, Flicker said.

“We usually have some combination of the two, where it’s huge to some extent, but you’re also able to flexibly direct power as needed, within a micro-network or between independent but cooperative micro-networks, as we explore for the moon. “Flicker said.” “In case of emergencies, such as the failure of an energy storage system during an eclipse, we want to be able to transfer the energy of the mining facility to the base camp to keep the astronauts safe.”

Part of the Flicker team is also exploring how the connection between the two micro-networks could work. They study the effect that the distance between the mining facility and the housing unit has on the efficiency and stability of the transfer, whether at a distance of 5 miles or 20. The team also determines the optimal voltage at which the connection should work and whether the connection makes sense. stay DC or if NASA needs to convert to AC to make the trip and then back to DC once it reaches the housing unit.

To answer these questions and study different contingency scenarios, Flicker and electrical engineers Rachid Darbali-Zamora and Andrew Doe use two research facilities.

Sandia’s Distributed Energy Technology Laboratory is used to study the integration of renewable energy resources such as wind turbines and solar panels into larger energy systems. One of the strengths of this lab is the hardware experiments in the cycle. These types of experiments involve connecting real hardware to software that can subject hardware to a variety of simulated scenarios, including catastrophic eclipses and weather conditions, Darbali-Zamora said. These experiments are an intermediate step between pure simulation and field tests, he added.

“With this DC power supply setup in the circuit we are building in the lab, we can test power converters, the impedance of power lines between lunar facilities, we could also test the actual power generation and storage devices,” Darbali said. Zamora. “In principle, we can use it to study different situations, so that we can design a system that is self-sustaining and can continue to work, even if the array of solar panels is damaged.”

The team will also use the Emera DC micronetwork at Kirtland Air Force Base to see how an electro-electron-heavy system can work and carry power if needed in unforeseen low-energy scenarios, Flicker said.

Of course, Sandia’s entire team is working closely together, Flicker added. For example, they use tool boxes from the Secure Scalable Microgrid test bench and some of NASA’s tool boxes in their computer simulations. Eventually, they even plan to test the Wilson controller in their connection simulations, Darbali-Zamora said.

“Although this work is for the micro-network of the Moon, the study is also important for creating the resilience of the Earth’s communities,” Darbali-Zamora said. “I’m from a small town in Puerto Rico. I hope some of the lessons that come from this sustainability project are lessons I can take at home.”


Feeding the Moon: Researchers are designing a micronetwork for a future lunar base


Provided by Sandia National Laboratories

Quote: Powering the Moon: Designing a Micronet for a Future Lunar Base (2022, May 12), retrieved on May 12, 2022 from

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