A standalone BLDC based solar air cooler with MPP tracking for improved efficiency

Abstract

This article proposes the idea of using Solar Energy (SE) as a source of power for designing and developing a standalone air-cooling system. This type of application is particularly suited for rural areas that have a considerable amount of solar radiation and have no access to grid systems. The proposed system is comprised of a photovoltaic (PV) array, DC-DC boost converter and DC-DC buck converter. Two Permanent Magnet Brushless Direct Current (PMBLDC) motors are employed to drive a centrifugal water pump and an air blower coupled to their individual shafts. The air blower is connected with a DC-DC boost converter that ensures a maximum power point (MPP) operation. A centrifugal water pump is connected with a DC-DC buck converter. The challenging task in an air cooling system is to maintain the constant speed of the blower under variable irradiance conditions. The power provided by the solar PV array can be shared between the two DC-DC converters in such a way that the BLDC motor connected with the blower will maintain a constant speed by maintaining the constant voltage of the DC-DC boost converter. The rest of the available PV power will be handled by the pump. The suitability of the proposed system for various perturbations is evaluated by simulating the proposed system using a MATLAB/Simulink and is validated by conducting experiments. Case studies have been performed with a variable PV irradiance and the results are explored.