Control of Grid-tied Three-level Four-leg Inverter Using Sliding Mode Controller Based on Fryze Current Minimization Technique

Topologically advanced power inverters are required to efficiently and economically integrate renewable distributed generators into the electricity grid while meeting the local load demand. The developed control system of these inverters is required to manage the injected active and reactive power from the distributed source according to the changes in the supply level and grid contribution. Furthermore, the controller is required to accurately and promptly track the generated reference currents for each phase. For these purposes, a sliding mode controller based on Fryze power theory is proposed to regulate the operation of a three-level four-leg inverter. The two incorporated methods are adopted because of their simplistic design procedure and their dependency on time measurements with minimal tunning. The achieved results demonstrated the effectiveness of the proposed design that offered low harmonic distortion and rapid tracking.