Wireless heliostat and control system for large self-powered heliostat fields

Abstract

The HELIOMESH project pursues the goal to evaluate and validate the feasibility of a wireless mesh network as control technology in a field of self-powered heliostats, thus eliminating the need for cabling. To enhance precision of control, an auto-calibration method was implemented. The team chose a combination of a practical approach combined with simulations to ensure scalability for large heliostats field to be build in the future: About 100 small communication devices, so called HelioNodes, are deployed in the DLR Solar Tower Demonstration Plant heliostat field, controlled by a base station located in the tower. The deployment validates the feasibility and the industrial capability of the wireless mesh control system. In simulations, the good performance of the wireless communication is shown for huge fields. Additionally, the auto-calibration technology was optimized and successfully tested using self-developed, self-powered 8m² heliostats. These heliostats were tested and optimized, with a focus on power management and drive efficiency. Results prove that stepper motors are a good choice in case state of the art electronics are used for control.