DEVELOPMENT OF HYBRID MPPT ALGORITHM UNDER PARTIAL SHADING CONDITIONS FOR LOW POWER APPLICATIONS

: Partial shading is a condition at which efficiency and stability of photovoltaic (PV) system are affected. During partial shading conditions multiple peaks rise in the PV characteristic curve. Conventional Maximum power point tracking (MPPT) techniques are unable to track the maximum power due to global maximum power point (GMPP) occurring during partial shading conditions conventional techniques as the power generated decreases. Therefore a Hybrid MPPT algorithm is proposed in this paper to speed up the power tracking efficiency of PV systems under partial shading conditions. The algorithm adjusts the duty cycle for regulating the input voltage at the Maximum power point (MPP) and to provide impedance matching ie. Input impedance of converter equal to equivalent solar impedance of PV system at MPP for the maximum power transfer. As Cuk converters have low switching losses and the highest efficiency it is selected as a power conditioning circuit. The influence of algorithm parameters on system behavior is investigated and the various advantages and drawbacks of the technique are identified for different weather conditions.Simulation results are validated by experimental results obtained using Solartech SPMO85P PV modules connected to the RL load through the Hybrid MPPT controller.