• Kanakaraju P
• G A Rathy

Abstract : Solar photovoltaic (PV) modules typically deliver 12-200 V DC, well below the 230-400 V bus voltages required by grid-connected inverters and DC loads, and conventional single-inductor boost or SEPIC converters can reach such gains only at duty ratios above 0.75, where switch stress, diode reverse-recovery loss and parasitic resistance dominate and erode efficiency. This paper presents the modelling, design and MATLAB/Simulink-based simulation of a high step-up SEPIC converter based on the SEPIC Two-Basic-Cell (SEPIC-TBC) coat circuit topology, in which n expandable passive basic cells – each a diode, two capacitors and an inductor – augment a conventional SEPIC without adding active switches. For n = 2, the converter achieves a voltage gain of M = 3D/(1-D), reaching a 230 V output from a 180 V PV input at a duty ratio of 0.30 while limiting switch and diode voltage stress to Vout/[(n+1)D], a 37.5% reduction relative to a conventional SEPIC at the same gain. A single-diode PV array model and a Perturb-and-Observe (P&O) maximum power point tracking (MPPT) algorithm are implemented in MATLAB/Simulink and validated in closed loop with the SEPIC-TBC converter. Simulation results show the MPPT controller settling the array near its 186 V maximum-power-point voltage, the converter regulating a 229.4 V / 2.29 A (526 W) output within 0.5 s, capacitor and switch voltages matching theoretical predictions to within 0.4%, and a peak conversion efficiency of 93.8% at 275 W, compared with 88.2% and 85.5% for conventional boost and SEPIC converters at the same operating point. A scaled laboratory prototype is also reported, in which a PIC16F877A-based closed-loop controller holds a 24 V output from a 20 W, 12 V-class PV module over a 2-12 V input window at duty ratios of 0.43-0.85, limiting switch stress to 21.1 V. These results support the SEPIC-TBC as a scalable, single-switch, high-gain interface for renewable PV systems.

sepic converter; high step-up dc–dc converter; sepic-tbc; coat circuit; photovoltaic (pv) system; maximum power point tracking (mppt); perturb and observe (p&o); matlab/simulink; renewable energy; voltage gain

"Performance Analysis of a High Step-Up SEPIC Coat Circuit Converter with P&O MPPT for Solar Photovoltaic Applications", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.13, Issue 9, page no.a656-a662, September-2026, Available :http://www.jetir.org/papers/JETIR2609081.pdf

"Performance Analysis of a High Step-Up SEPIC Coat Circuit Converter with P&O MPPT for Solar Photovoltaic Applications", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.13, Issue 9, page no. ppa656-a662, September-2026, Available at : http://www.jetir.org/papers/JETIR2609081.pdf