Model-Based Method for Partially Shaded PV Module Hot-Spot Suppression

Hot-spot suppression is a new method to operate a photovoltaic (PV) module that prevents the formation of hot spots with no need for bypass diodes. By comparing the operating voltage, current, and temperature with an intrinsic I(V) model that is based on calibrated flash test data, hot-spot suppression determines the solar modules´ shading condition and, if required, seeks a new operating power point that reduces the formation of hot spots on shaded cells. Hot-spot suppression works in concert with a model-based maximum power-point-tracking algorithm to seek the best operating point for the maximum output power while limiting stress on shaded cells on the solar module. Theoretical and experimental results show that the power density dissipated in the shaded cell(s) is reduced by a factor of 4 when the operating conditions are determined by hot-spot suppression.