This project presents a development of a software for a three-phase islanding inverter. Islanding inverters are used in off-grid systems (i.e. when a connection to the main grid isn’t available), the inverters are supposed to supply the load with the voltage and current it needs, to achieve this task, a Proportional-Integral (PI) controller was designed and software was written for the “TMS320F28069 DSP” that is the brain of "AMER" extra low voltage power electronics kit available at the department of Control Engineering and Informatics at Budapest University for Technology and Economics.
The main goal of the project was for the TMS320F28069 DSP to generate three-phase voltages and perform AC current and voltage regulation which was measured and confirmed by both, a software recorder and an oscilloscope. Further enhancement for the output waveform was carried out using a dead-time compensation technique and symmetric waveform modulation.
A drawback of PI controller is the inability to control the output for asymmetric loads, another controller called “Resonant PI Controller” was developed and a software was written for it. The software wasn’t tested and left for future development and testing.