Investigation of DC-AC converter with microcontroller control of inverter frequency

The paper discusses the key aspects of the development of a frequency-controlled direct current to alternating current (DC-AC) converter based on a microcontroller. Electric energy converters play an important role in ensuring energy stability, especially in the conditions of frequent and unpredictable power outages, which are characteristic of Ukraine. Emphasis is placed on improving the parameters of the inverter to increase its efficiency, stability of operation, and the possibility of using alternative energy sources, such as batteries and solar panels. The work investigates the structure and principle of operation of the inverter, which includes such main components as a direct current source, a MOSFET bridge, a low-frequency filter, and an output transformer. A voltage frequency control circuit using an ATmega328P microcontroller is proposed, which allows for maintaining a stable output voltage under conditions of changing input voltage parameters. The research methodology involved conducting an experimental analysis based on a symmetric non-composite Box-Benkin plan, which made it possible to optimize the design of the device. In particular, the influence of the parameters of the secondary winding of the transformer, the power of the transistors, and the input voltage on the output power of the device was studied. The obtained results demonstrated the efficiency of the device with a rational choice of element base. In the course of the research, a mathematical model of the process of optimizing the converter parameters was developed. It was concluded that increasing the power of field-effect transistors and changing the geometrical parameters of the transformer contribute to increasing the performance of the device. Prospects for further research include modernization of the microcontroller software, integration of protective sensors, and adaptation of the device to work with different types of loads.