An Improved MPPT for Partially Shaded PV System by Coalescing INC with PSO Algorithms

Solar Photovoltaic (PV) power generation has assumed particular significance as a very reliable and abundant source of renewable energy due to the numerous advantages it has on offer, such as being environmental friendly and demanding very low maintenance costs. For a large solar PV system, the probability of occurrence of partial shading is indeed huge, leading to poor or limited power extraction from the PV array. Under partial shaded conditions (PSC) power-voltage characteristic (P-V) curve of the PV array exhibits multiple maximum power points (MPPs) locally, which conventional MPP tracking (MPPT) control algorithms fail to trace when it comes to smoothly tracking down global MPP (GMPP). This paper presents an improved MPPT algorithm which is far quicker and is adept at tracking GMPP accurately under PSC. The MPPT algorithm proposed in this paper is formed by coalescing incremental conductance (INC) with particle swarm optimization (PSO) method. This combination offers less iteration count to reach GMPP and also avoids the possibility of pre-convergence. The proposed technique is supported by providing simulation studies.