Nonlinear Modeling of Three-Phase Inverters for Advanced Control Applications

This paper presents the modeling and analysis of a three-phase, two-level voltage source inverter connected to a photovoltaic system and the electrical grid. The study begins with a detailed review of the Park transformation and Pulse Width Modulation (PWM), essential tools for controlling and analyzing the inverter's operation. The dynamic model of the inverter is developed, incorporating state-space representations to capture the system's behavior under various operating conditions. The model considers key factors such as synchronization with the electrical grid, the effects of filtering components, and the role of photovoltaic current as an input. This mathematical framework serves as a foundation for implementing advanced nonlinear control strategies and can be extended to different inverter applications beyond photovoltaic systems.