Modeling of voltage source inverter having active split DC-bus for supply of four-wire electrical utility systems

The proposed paper deals with the modeling, analysis, and validation of an active split DC-bus configuration to be intended for three-phase four-leg inverters. By State Space Averaging technique, the active split DC-bus topology is analyzed to derive the mathematical model that is suitable to represent both steady state and dynamic behavior, taking into account main converter non-idealities. The mathematical model has been validated by comparing the obtained transfer functions and system responses, with the switching model based simulations achieved with the aid of Matlab/Simulink and finally with a properly designed inverter. Proposed analysis allows to obtaining the guidelines on passive components sizing, according to a three-phase plus neutral converter topology working in isolated power distribution systems.