Fast Partial Shading Detection and Performance Analyzing Method for Photovoltaic Generation

Detecting the partial shading (PS) condition on PV panels is vital to prevent energy losses. Also, it is an essential trigger mechanism to activate the differential power processing and voltage balancing applications to increase the generated power. To this end, a fast PS detecting method is introduced in this paper, which provides information about the number of PV panels in PS conditions and the shading rate on each PV panel. To achieve this goal, a pulse current source is placed between the PV panel and the terminal capacitor to sweep its output characteristics in a very short time. In addition, an implementation of the proposed method through a wave-shaping converter is used. Besides the high-speed PS detection, avoiding a short-circuit in the terminal capacitor of the PV panel is another advantage of this method which does not have a detrimental effect on the lifetime of the system. Moreover, the proposed method is designed in a way that it can work with any existing MPPT techniques. Also, the developed circuit and prototype controller are designed in order to maintain the voltage drop across the terminal capacitor in a satisfactory range. The experimental results demonstrate the efficiency and feasibility of the proposed method.