Today, environmental pollution has increased due to excess use of fossil resources. Amidst, renewable energy resources, solar energy is one of the infinite, clean and accessible options. Each solar cell has a unique operating point which is called maximum power point. Considering nonlinearity of I-V and P-V curves of Photovoltaic (PV) resources, their delivered power depends on operating point of the PV. That is, for changes in temperature or irradiation, some actions should be taken to obtain maximum operating point which is called maximum power point tracking (MPPT). This paper tries to configure power circuit using distributed maximum power point tracking (DMPPT) with a fly-back converter, optimize power and reduce fluctuations around maximum power point. MPPT is analyzed through simulation using P&O, INC and zero fluctuation, adaptive step, increasing (ZA-INC) guidance algorithms in two steps including variable irradiation with constant temperature and variable temperature with constant irradiation using DMPPT and centralized MPPT. In DMPPT scheme using ZA-INC algorithm, power is optimized, losses are reduced, fluctuations around maximum power point are reduced, gain and tracking speed are increased.