Photovoltaic System Based on Upon Inductor-Coupled Step-Up-Down DC-DC Converter and an improved incremental conductance MPPT algorithm

This paper offers a photovoltaic system based on a simpler fast-converging maximum power point tracking technique and upon Inductor-Coupled Step-Up-Down converter with positive output voltage which combines the KY converter and the traditional synchronously rectified (SR) buck converter. The relationship between the load line and the I–V curve is used with trigonometry rule to obtain the fast response. Traditionally, maximum power point (MPP) locus was used to provide such a fast response. However, the algorithm requires extra control loop or intermittent disconnection of the PV module. Hence, this paper uses a MPPT technique, which excludes the extra control loop and intermittent disconnection. Actually, the KY converter and the SR buck converter, combined into a Step-Up-Down converter that has some advantages such as: it doesn't have right-half plane zero, it possesses the non-pulsating output current, thus not only decreasing the current stress on the output capacitor but also reducing the output voltage ripple and etc. Therefore, due to its advantages and its buck-boost operation, it is suitable for photovoltaic utilizations. The performance of the developed system has been analyzed by means a simulation platform in Matlab/Simulink.