Improved perturbation and observation method (IP&O) of MPPT control for photovoltaic power systems

Maximum power point tracking (MPPT) is used in photovoltaic (PV) system to maximize the PV array output power irrespective of temperature and irradiation conditions. In this paper, an improved perturbation and observation method (IP&O) based on adaptive algorithm is proposed, which is automatically adjusts the reference step size and hysteresis bandwidth for power comparison. The digital signal processor (DSP) was used to implement the proposed MPPT control system, which controls the dc/dc boost converter in the 3 kW grid-connected PV power systems. The experimental results show that the IP&O increases the total PV output power by 0.5% at an unsettled weather condition compare to traditional perturbation and observation method (P&O).