Solar collector and drive circuitry control means

Claim 1

A Solar Collector Controller comprising a solar sensor array, an electronic data processor and amplifier, a drive motor, a gear train, and means for mounting the controller on a gimbaled solar collector, said sensor array being a set of four sensors oriented in pairs at a 90° angle, each pair being oriented perpendicular to its neighbor so as to form a sensitive surface consisting of four sensor surfaces arranged to produce electrical signals, each pair of signals being summed differentially to produce an error signal having phase and amplitude proportional to the orientation of the sensor pair with respect to the incident solar flux, said sensor pairs being oriented parallel to and orthogonal to the diurnal path of the sun, said orientation providing an electrical signal proportional to azimuth and elevation of the solar normal in its cycle, said sensor array being placed below a shadow plate, said plate having an area smaller than the area of the sensor array so that a portion of the array is thereby shaded, said shading being equal when the sensor joint normal is parallel to the solar normal, said array then producing a null output, otherwise the relative solar angle produces an error signal proportional to the angle, an amplifier with a variable gain receiving said error signal, a fifth solar cell for controlling said variable gain connected in a feedback path across the amplifier, said amplifier output being applied to drive a motor and gear train mounted so as to position the solar collector carrying the radiation sensor array, the amplifier means arranged so as to drive the solar collector to reduce the relative solar angle to a null position for maximizing solar collector efficiency, control circuit means connected to said amplifier means for restoring the solar collector orientation to an easterly position when the solar irradiance on the sensor array falls below a pre-set threshold after sunset.