Heliostat System Configuration
A typical heliostat system configuration is shown in Figure 7.9 and its essential components include sensor housing, mirror, elevation and azimuth control circuits, counter weight for static balance, and mechanical support. A sighting alignment hole plays a key operational role. A two-axis heliostat control is necessary for smooth and efficient system operation . The heliostat control can be obtained by using either a hydraulically or electrically operated servomechanism, which drives a signal from a simple position-sensing phototube device. The heliostats typically range from 3 to 10 m2 are spaced over a field with radius equal to one to two times the tower height in such a manner that they are largely visible from the receiver to minimize shading as the sun crosses the sky. Solar collectors bearing an obvious
resemblance to a tower-top focus collector have been investigated by various scientists and engineers who were interested in developing high power thermal sources using solar technology.