Standalone Single Phase DC-AC Inverter with FPGA-based Pulse Modulated Generator Unit

This paper presents the design of a pulse modulation signal generator using a Field Programmable Gate Array (FPGA) to control the power switch devices used in an inverter that are arranged in full bridge configuration. A single-phase inverter is designed for stand-alone operation mode in renewable energy-based power supply system. FPGA is an electronic device that works digitally and has the advantage of being able to work at high frequency and high concurrent computing capability. The modulated pulse signal is generated by comparing a sinusoidal wave and triangular wave generated digitally using the Look-Up Table (LUT) method to retrieve an amount of voltage data at some points of sampling. The data obtained is then stored in the FPGA internal memory. To test the hardware, an LC filters are used to reduce harmonic caused by the switching process and produce pure sinusoidal output quality. System validation is made using two methods, i.e. SPICE simulation and testing on the real inverter unit. Total harmonic distortion (THD) of the inverter hardware is measured and analyzed.