DESIGN AND CONSTRUCTION OF 3KVA OF PURE SINE WAVE INVERTER WITH INBUILT CHARGE CONTROLLER

ABSTRACT This project presents the design and construction of a 3KVA pure sine wave inverter with an inbuilt charge controller. The system was developed to provide an alternative and reliable source of electrical power due to the unstable nature of public electricity supply in Nigeria. The inverter converts 12V direct current (DC) from a battery source into 220V alternating current (AC) suitable for powering domestic and office appliances. The project consists of major units which include the input unit, processing unit, driving unit, transforming unit, output unit, and charging control unit. The processing unit was implemented using a PIC16F876A microcontroller programmed in C-language to generate Pulse Width Modulation (PWM) signals required for producing a pure sine wave output. The driving stage utilized IRF3205 MOSFETs for switching operations, while the transformer section stepped up the low DC voltage to the required AC output voltage. The inverter was designed to deliver a maximum output power of 3KVA at 220V AC and 50Hz frequency. Various tests were conducted on the system units, and the results obtained showed stable output voltage ranging between 220V and 224V AC. The inbuilt charge controller enhanced battery charging efficiency and ensured proper battery management during operation. The completed system was found to be portable, noiseless, efficient, and suitable for homes, offices, churches, laboratories, and small business applications. The project successfully achieved its aim of constructing a reliable pure sine wave inverter capable of providing uninterrupted power supply during power outages.