TY  - JOUR
A1  - Reger, Vitali
A1  - Kuhnhenne, Markus
A1  - Hachul, Helmut
A1  - Döring, Bernd
A1  - Blanke, Tobias
A1  - Göttsche, Joachim
T1  - Plusenergiegebäude 2.0 in Stahlleichtbauweise
JF  - Stahlbau
Y1  - 2019
U6  - https://doi.org/10.1002/stab.201900034
SN  - 1437-1049 (E-journal), 0038-9145 (print)
VL  - 88
IS  - 6
SP  - 522
EP  - 528
PB  - Ernst & Sohn
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Sattler, Johannes, Christoph
A1  - Röger, Marc
A1  - Schwarzbözl, Peter
A1  - Buck, Reiner
A1  - Macke, Ansgar
A1  - Raeder, Christian
A1  - Göttsche, Joachim
T1  - Review of heliostat calibration and tracking control methods
JF  - Solar Energy
N2  - Large scale central receiver systems typically deploy between thousands to more than a hundred thousand heliostats. During solar operation, each heliostat is aligned individually in such a way that the overall surface normal bisects the angle between the sun’s position and the aim point coordinate on the receiver. Due to various tracking error sources, achieving accurate alignment ≤1 mrad for all the heliostats with respect to the aim points on the receiver without a calibration system can be regarded as unrealistic. Therefore, a calibration system is necessary not only to improve the aiming accuracy for achieving desired flux distributions but also to reduce or eliminate spillage. An overview of current larger-scale central receiver systems (CRS), tracking error sources and the basic requirements of an ideal calibration system is presented. Leading up to the main topic, a description of general and specific terms on the topics heliostat calibration and tracking control clarifies the terminology used in this work. Various figures illustrate the signal flows along various typical components as well as the corresponding monitoring or measuring devices that indicate or measure along the signal (or effect) chain. The numerous calibration systems are described in detail and classified in groups. Two tables allow the juxtaposition of the calibration methods for a better comparison. In an assessment, the advantages and disadvantages of individual calibration methods are presented.
Y1  - 2020
U6  - https://doi.org/10.1016/j.solener.2020.06.030
VL  - 207
SP  - 110
EP  - 132
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Göttsche, Joachim
A1  - Alexopoulos, Spiros
A1  - Dümmler, Andreas
A1  - Maddineni, S. K.
T1  - Multi-Mirror Array Calculations With Optical Error
N2  - The optical performance of a 2-axis solar concentrator was simulated with the COMSOL Multiphysics® software. The concentrator consists of a mirror array, which was created using the application builder. The mirror facets are preconfigured to form a focal point. During tracking all mirrors are moved simultaneously in a coupled mode by 2 motors in two axes, in order to keep the system in focus with the moving sun. Optical errors on each reflecting surface were implemented in combination with the solar angular cone of ± 4.65 mrad. As a result, the intercept factor of solar radiation that is available to the receiver was calculated as a function of the transversal and longitudinal angles of incidence. In addition, the intensity distribution on the receiver plane was calculated as a function of the incidence angles.
KW  - solar process heat
KW  - concentrating collector
KW  - raytracing
KW  - point-focussing system
Y1  - 2019
SP  - 1
EP  - 6
ER  -