A nonlinear modeling approach for high performance solar angle sensors

Sun tracker is an automatic device that steers a PV array perpendicular to the solar irradiation, improving power output up to one-third. However, its feedback control is lack of accurate angle measurement that degrades the overall performance. A type of irradiation angle sensors is proposed in which the pyramid structure generate some currents containing the information of irradiation angle. To extract the information, we derive a nonlinear function with uncertainties to map the irradiation angle and develop a nonlinear optimization method to discern uncertain parameters from experimental data. Experimental results show that the irradiation angle sensor, calibrated by the grey-box system identification method, is accurate and precise. It solves the bottleneck problem of sun trackers with feedback control mechanism.