Plugging in on the Moon
Power and in-situ resources are two things humans will need as they explore deep space. How future astronauts use these commodities depends on the technology at hand. That's why NASA is looking to U.S. universities for lunar-focused research to bring about advancements in sustainable power solutions and available resource utilization.
NASA selected six project proposals under its first-ever Lunar Surface Technology Research (LuSTR) solicitation, one of which is led by Ohio State University Electrical and Computer Engineering Professor Jin Wang.
Ohio State’s research team is one of three tasked to mature next-generation energy storage and power distribution technologies on the Moon. With a two-year, $1.6 million grant, Wang and his collaborators will explore flexible energy distribution between multiple micro-power grids – using solar, radioisotope, and battery sources – that could be deployed on the lunar surface to support the Artemis program. The project will focus on control methodologies and perform both hardware and software demonstrations.
Projects collaborators include engineers at Ohio State’s Center for High Performance Power Electronics and Center for Automotive Research, as well as Raytheon Technologies Research Center.
Spacecrafts, ascent stages, lunar rovers, and habitats all require proper control and protection of onboard direct-current (DC) power microgrids. According to Wang, power systems for lunar applications can benefit significantly from recent developments in advanced controls of DC power microgrids, solid state circuit breakers and wide band gap (WBG) high-density power converters. Previously, with NASA funding support, his team successfully demonstrated a “smart resistor” concept, which delivered multiple stability improvements for DC microgrids’ constant power loads (CPL). In 2019, Wang earned a Department of Energy ARPA-E grant to develop highly reliable and efficient circuit breakers for DC-based electric power distribution.
The Ohio State team will create and demonstrate a modular DC-energy router that not only can function as a power flow controller, but also as an intelligent circuit breaker, thus realizing interconnections and power flow optimizations between multiple lunar surface power systems. During the project, the team will focus on energy routing and system stability enhancement, over current and fault current limiting, digital twin and model-predictive control, sensor placement optimization for system reliability, and concept validations with a 120 V, 10 kW prototype.
“I believe many research groups around the nation that work on power systems and power electronics submitted proposals, so we feel very fortunate that we were the first one selected,” Wang said. “Our proposal leveraged the outcomes of our previous NASA and ARPA-E projects, combining two ideas into one to develop a very unique energy router.”
The proposed DC-Energy Router will combine typical control functions of power converters and fault handling functions of circuit breakers into one modular circuit with enhanced flexibility to accommodate a wide range of different voltage, current and energy requirements for all types of lunar power systems.
Via the LuSTR selections, NASA aims to stimulate lunar technology development within academia and help fast-track the readiness of critical lunar technologies and components.
"Our inaugural LuSTR opportunity targeted two technology areas within NASA's Lunar Surface Innovation Initiative that are essential to the agency's Artemis program, which will land the first woman and next man on the Moon," said Walt Engelund, deputy associate administrator for programs in NASA's Space Technology Mission Directorate (STMD). “The systems developed by U.S. universities could make future exploration more accessible, robust, and exciting.”