ANALYSIS AND DESIGN EVALUATION OF A DC POWER INVERTER

ABSTRACT An inverter is an electronic device that takes a direct current input and produces a sinusoidal alternating current output. The power electronic device called inverter which is used to convert the dc power to ac power at desired output voltage. It maintains a continuous supply of electric power to connected equipment’s or load by supplying power from a separate source, like battery, when utility power is not available. It is inserted between the source of power and the load is protecting. In this project, the design, construction and evaluation of a DC to AC inverter (1.5 KVA square wave, push-pull pulse width modulation inverter) the methods implemented for the design were DC to AC inverter topology, the DC to AC inverter circuit made use of a microprocessor to digitally pulse the transistors on the inverter side of the circuit. The project was broken down into smaller components and tested individually at every different stage of the design by the oscilloscope and digital multi-meter for their unique specification. After component tests, they were incorporated for final assembly and integration. It is designed to meet up with the power demand in the offices and in homes in the absence of power supply from the national supply authority, NEPA. In order words the device / item serves as a substitute for NEPA which almost monopolize the power supply to people. It is designed in such a way that it will take up 12v DC from battery and inverts it to an output of 220v, 50H2 AC. It makes no noise during operation and no hazardous carbon monoxide is generated in the surrounding. This is a feature that makes it safe to use any were when compared to generator. Also, the circuit is capable of charging the battery (i.e. 12v source) when the power from the supply authority is on. This greatly reduces the cost of operation of the system.