Sensor module for concentrated photovoltaic technology using point-focusing fresnel lens

Abstract

Sensor module for concentrated photovoltaic (CPV) technologies using a point-focusing glass Fresnel lens, whose sensor housing (1) is designed as a straight truncated square pyramid, where in an implemented sensor module, has, on its side surfaces facing north, south, east and west, photoresistors (3) with reduced active surfaces (4) as indirect radiation detecting photosensors. At the top of the sensor housing (1), a focal pinhole (8) is formed centrally, and the direct sunlight detecting lens (6) is centrally connected to the top of the sensor housing (1) via a spacer element (7) made of opaque material, the optical axis of which coincides with the longitudinal axis of the sensor housing (1) and the center of the focal pinhole (8).  The optical focal point (10) of the lens (6) coincides with the focal pinhole (8) in the plane of the top of the sensor housing (1) and coincident with the optical axis of the lens (6) inside the sensor housing (1). The central photosensor (9) is arranged at a distance to the optical focus point (10) of the lens (6), therefore it is not damaged by concentrated direct radiation. When the focal pinhole is located, the direct radiation falling on the photosensor stops the sun tracking exactly, while the CPV cells deliver the maximum power. The electrical output of the photosensors (9) is connected to the control unit used in current photovoltaic technology.