A novel fast mutable duty (FMD) MPPT technique for solar PV system with reduced searching area

In this paper, a novel maximum power point (MPP) tracking technique for photovoltaic system (PV) with fast convergence speed and reduced range for the MPP search operation is presented. The characteristic of this method is the limited searching area/range for the tracking. The adaptable variable duty step used in the proposed method instantaneously brings the operating point close to the MPP, thus bounding the searching area. The value of duty gets updated according to the panel temperature and irradiance, and the operating point always remains close to the MPP. By bounding the search operation, the overall tracking speed and efficiency of the tracking increase. Further enhancement of the tracking speed is obtained by varying the step size of duty ratio of the DC-DC converter used; this is done in such a manner that the size of variable duty step is large for the points far away from MPP and becomes very small at or near MPP. The projected tracking algorithm is compared with conventional Perturb and Observe MPPT method in diverse irradiance and temperature conditions, and evaluation of the proposed tracking method is reported. Finally, field performance of the proposed method has been done by using a 250 W PV system. Arduino Uno microcontroller board is used for controlling the duty of the DC-DC converter. Results obtained from the hardware implementation have been presented and is concluded that the method has fast tracking capability and better efficiency. To sum up, overall performance of the proposed Fast Mutable Duty MPP Tracking technique is appreciable.