Session: 05-12 Heliostat Consortium 2

Paper Number: 110772

110772 - Nsttf Heliocon Wireless Closed-Loop Controls Test Bed Development 

A closed loop controls test bed is in development at the Sandia National Laboratories solar tower facility as part of the U.S. DOE SETO Heliocon program. This work pertains to preliminary development of advanced feedback controls for a concentrating solar power (CSP) field of 218 heliostats, and a power capacity of 6 MW_th t. This work will review progress of the highly-flexible controls and sensors which will be communicating with both wired and wireless protocols. Operational modes will be evaluated for varying pointing strategies and error determination. A comprehensive review will assess different closed loop control architectures, which was used for the final down-selections which are being employed for different CSP heliostat commercial systems. This includes algorithmic software architectures, utilized to determine optimal pointing of each heliostat, accounting for unique metrology considerations. The flexible solar field distributed control system (DCS) manages the flux distribution of energy across test articles and solar receivers using real-time heliostat-aiming and closed-loop feedback algorithms for solar field. Feedback control is facilitated with a variety of sensors, located: 1. On the heliostat, 2. On the tower or 3. At an ancillary field tower station. The system is also developed to incorporate environmental information to provide real-time feedback into advanced algorithms for solar field management.

Presenting Author: Kenneth Armijo Sandia National Laboratories

Presenting Author Biography: Dr. Kenneth Armijo is a systems engineering staff member who leads molten salt and molten alkali metals R&D at the National Solar Thermal Test Facility (NSTTF). His research interests are in alternative energy technologies and sustainability, as they pertain to scientific and technological innovation, business and policy. Dr. Armijo holds a Ph.D. in Mechanical Engineering from the University of California, Berkeley with minors in Energy and Resources, and business credentials in Management of Technology from Berkeley's Haas School of Business. Dr. Armijo also received a Masters in Science in Mechanical Engineering from U.C. Berkeley. Presently, Dr. Armijo’s research in concentrating solar power (CSP) consists of system design for high-temperature (>720 °C) thermodynamic and commercial R&D systems, employing ternary chloride molten salts and alkali metals (sodium) as the heat transfer fluid. He is the test site Principle Investigator (PI) for multiple U.S. Dept. of Energy (DOE) projects in CSP that also includes pumped thermal energy systems. His research has also consisted of falling particles for centralized concentrating solar receivers and solar reactors for industrial process heat applications and climate change mitigation technologies. He also leads research activities pertaining to solar Stirling Engine applications as well as for solar reactor R&D and high-flux materials characterization. Dr. Armijo also serves as a lead Test Director for high-temperature materials research for Aerospace applications, such as Re-Entry and Hypersonic vehicles.