Design and Construction of an Inverter for University ICT Loads

Abstract

In trying to restore a stable power generation in this part of the world for effective research studies and to improve administrative duties in the University of Nigeria Nsukka, this paper discusses the design and construction of a single phase inverter for information communication and technology equipment’s (ICT) which includes printers, computers, and network switches etc. The inverter system converts the DC voltage from a battery to AC voltage. The output is a pure sine wave, with the voltage and frequency of the standard grid (50Hz, 230V). A pulse width modulated (PWM) switching scheme together with a full bridge converter and filter is use to realize this design. The sinusoidal pulse width modulation (SPWM) switching scheme is the main logic control circuit of this inverter and provides a PWM output using operational amplifiers and microcontroller. This logic circuit is connected to a driver circuit to ensure sufficient gate driving current and voltage for the full bridge converter (H-bridge) switches (power MOSFET). The pulse signals are used to drive MOSFET in a H-bridge configuration to produce an output that is bipolar The output of this inverter switches from positive to negative (bipolar). This output from the MOSFET when filtered produces a sine wave output. This project is implemented and simulated using MATLAB simulation software.