Novel single-voltage-sensor-based maximum power point tracking method

A novel maximum power point tracking method for photovoltaic systems based on a single voltage sensor is proposed in this paper. By means of the simulation studies with PSIM software, it has been found that there are similar relationship curves between the expression (C - d)middot(-DeltaV_PV) and the actual power P_PV of a photovoltaic array regardless of the chopper stage topology connected to the array. Therefore the maximum power point tracking based on P_PV is replaced with the expression (C - d)middot(-DeltaV_PV). For the purpose of diminishing the power fluctuation in the steady state, the averaged voltages of a photovoltaic array and the average duty ratios are used for the calculation. Experimental results obtained on a 50 W prototype of a lead acid battery charger show high performance such as the less power fluctuation and the less ambient, i.e. irradiation and temperature, influence.