Performance Analysis of High Step-Up Dc-Dc Converter for PV System fed BLDC Motor drive

Abstract

In this paper, the conventional DC-DC converter is replaced with a High Step-up Converter for the solar power applications. The performance of converter-inverter technology to drive a brushless DC motor is analyzed. The high step-up dc-dc converters are used to produce high step-up gain. Theoretically the boost converter can provide the high voltage gain at large duty cycle. But in practice the voltage gain is reduced, due to losses in utilized components like rectifier diode, power switch, inductor and capacitor. Hence the converter using coupled inductor technique was introduced. However, the leakage inductor cause voltage transients on main switch and also reduce the conversion efficiency. To mitigate the voltage stress on the main switch due to voltage spike/transients, the coupled inductor with active clamp circuit based converters are introduced. They are different from other existing DC_DC step up converter and possess obivious advantages, mainly including fewer switches, clear conversion processes and a high voltage with simple ripples. The speed of the BLDC motor is controlled by varying the dc-link voltage source inverter (VSI). A low-frequency switching of the VSI is used for achieving the electronic commutation of BLDC motor for reduced switching losses. The voltage transformation is doubled. The simulations are done with MATLAB/SIMULINK and the results are exhibited.