DC ripple regulation of single-phase converters with reduced harmonic impact

Single-phase power converters are commonly employed to integrate renewable sources, such as solar PV or fuel cells, among other applications. However, they typically require large and limited lifetime electrolytic capacitors to filter large DC side ripple components, representing a limit for the power density and durability of converters, potentially making the technology unpractical for some applications. Alternatively, active filtering methods can be used to lower DC capacitor requirements and enable the use of durable film capacitors with minimum sizing. This paper presents a closed loop control strategy that applies single-input space vector theory in order to increase component utilization, and decrease AC harmonic content. A systematic approach is introduced to achieve DC side harmonic mitigation without increasing the DC side capacitance requirement. Simulation results are presented in Matlab/Simulink™ to compare two active filtering topologies using the proposed control with a conventional DC-AC single-phase topology.