The rapid increase in the cost of conventional energy sources lends to the use of nonconventional energy sources. The photovoltaic (PV) is one nonconventional source that is safe, reliable, and environmentally healthy. However, the PV system is Expensive and needs a large area to operate. To solve these disadvantages, it is necessary to operate at the maximum power point (MPP) of the array. This article presents a new maximum power tracking algorithm based on the incremental conductance algorithm which successfully operates even in cases of rapidly changing atmospheric conditions. The developed algorithm depends on the relationship between the load line and the tangent line angles of the I-V characteristic curve. A simulation program was designed to investigate the performance of the developed algorithm using mathematical models for the different system components. The simulation led to a good realization of the algorithm.