Method to determine the tracking angles of heliostats

Area of Science:

• Solar energy engineering
• Optical engineering
• Robotics and control systems

Background:

• Heliostat tracking accuracy is crucial for efficient solar thermal power generation.
• Existing methods often require orthogonal tracking axes, limiting applicability due to manufacturing or degradation imperfections.
• Addressing arbitrary orientations and offsets is essential for robust heliostat performance.

Purpose of the Study:

• To develop a unified method for determining heliostat tracking angles applicable to arbitrary axis orientations and offsets.
• To provide a solution that overcomes the limitations of orthogonal axis requirements in heliostat design.
• To facilitate the practical application of advanced heliostat aiming strategies.

Main Methods:

• A generalized kinematic model for two-axis tracking heliostats is formulated.
• The method iteratively calculates tracking angles, accommodating non-orthogonal axes and inter-axis offsets.
• A Python library (HelioK) and a 3D Blender model are developed to support the method's application and visualization.

Main Results:

• The presented method successfully calculates tracking angles for heliostats with arbitrary axis orientations and offsets.
• Fast convergence of iterative results is demonstrated for typical solar thermal plant parameters.
• The approach unifies various heliostat configurations, including local and global aiming, and single-axis trackers.

Conclusions:

• The developed method offers a versatile and accurate solution for heliostat aiming, enhancing solar energy concentration.
• The HelioK library and accompanying 3D model provide valuable tools for researchers and engineers in the field.
• This work advances the design and control of heliostats, particularly in scenarios with non-ideal axis configurations.