ABSTRACT
This study focuses on the design, implementation, and testing of a 1.5 KVA hybrid sine wave solar inverter system aimed at powering a refrigerator in Benin City, Nigeria, where grid power is unreliable and typically available for only 8 hours per day. Given the frequent power outages in the region, the inverter was designed to ensure continuous operation of the refrigerator during periods of grid failure by seamlessly switching to solar power. The design process included analyzing refrigerator power consumption patterns, factoring in both startup surge currents and steady-state operation, which are crucial for ensuring the system's efficiency and reliability. The project utilized advanced power electronics components such as MOSFETs, capacitors, and transformers, selected for their ability to facilitate efficient power conversion. Additionally, the system incorporated MPPT (Maximum Power Point Tracking) technology, which dynamically adjusted the solar panels’ operating point to maximize energy harvest. A detailed block and schematic diagram outlined the system's architecture, while simulations and modeling helped optimize performance before fabrication. The inverter system was also equipped with safety mechanisms such as overload and short-circuit protection to ensure safe and reliable operation. A workflow diagram was used to streamline the development process, ensuring efficient communication and resource allocation. The project yielded promising results. The hybrid sine wave solar inverter was able to provide continuous power to the refrigerator for approximately 8 hours per day, effectively bridging the gap during periods of grid unavailability. The solar panels, coupled with a 75 Ah battery, harnessed and stored sufficient energy during daylight hours to sustain the refrigerator overnight. The inverter’s MPPT feature optimized energy collection from the solar panels, contributing to its high efficiency. Testing showed that the system could power the refrigerator consistently for over 8 hours, validating the calculated battery discharge time. No-load and load tests confirmed the inverter's stable output voltage, efficient power conversion, and safe operation under varying conditions. This highlights the project's success in providing a sustainable and cost-effective power solution for regions with limited grid access.
