A Soft-Switching DC-DC Boost Converter for Extracting Maximum Power from SPV Array

Power electronic converters play an important role in extracting maximum power from solar photo voltaic (SPV) sources. Conventional hard switching power converters, used in SPV systems encounter with the problems of high switching loss, large voltage and current stress of switching devices and large EMI & RFI. These effects are more pronounced with high switching frequency operation leading to efficiency reduction. However, soft-switching dc-dc converters with quasi-resonant pulse-width modulated (PWM) switching operation can overcome above limitations even operating at high switching frequency. This work presents a new softswitching DC-DC boost converter for extracting maximum power from SPV array. The proposed converter uses an auxiliary network (AN) to operate the main and the auxiliary switch of the proposed converter either under zero voltage switching (ZVS) and/or zero current switching (ZCS) conditions. The proposed converter has been designed, simulated in MATLAB/Simulink platform and its real time performance has been verified in the laboratory. A simple and cheap PIC microcontroller operating with P&O algorithm has been used to generate the switching PWM signals for the maximum power point tracking (MPPT) operation. The converter was operated with a switching frequency of 45 kHz and the measured efficiency was 95.23%.