A Self-Sustaining Photovoltaic Power System with High-Gain Boost Converter for DC Nanogrid Equipped with Hybrid Storage Unit

Abstract

This paper presents the design and control of a high gain boost converter (HGBC) for a stand-alone solar photovoltaic system supported by a battery-ultracapacitor (UC) based hybrid storage unit (HSU). It achieves a higher voltage conversion ratio compared to a conventional boost converter by stepping up the input voltage, which is especially useful when the solar panel output voltage is low or when specific output voltages are required for various applications. This extended voltage range provides more flexibility in system design and allows for compatibility with a wider range of devices. The implementation of maximum power point tracking (MPPT) algorithms play a crucial role in accurately tracking the maximum power point (MPP) and effectively responding to dynamic changes in environmental conditions. This PV system with HSU is integrated to the DC bus through two bidirectional converters for regulating the grid voltage to the desired value using a filtration-based dual-loop control strategy. The entire nanogrid power management along with bus voltage regulation is achieved under irradiance and load change scenarios. This system stands out because of its simple design, enhanced efficiency and substantial gain to achieve higher output voltages without the need of isolation stages. The uniqueness of the complete system can be a promising solution for PV-based water pumps and EV charging stations.