Modified split-source inverter with single-phase dual power decoupling

Split-source inverter (SSI) is a topology developed for flexibly stepping up and down its ac output voltage using only a standard inverter bridge. However, when configured as a single-phase inverter, it is still burdened by common second-order ripples. This study, therefore, proposes a modified SSI (MSSI) that can perform dual power decoupling. Unlike existing schemes, dual power decoupling makes use of both dc- and ac-side capacitors for diverting second-order ripples away from the dc source, which may be solar or other types of sources that do not work well with sizable ripples. Dual power decoupling, however, requires careful topological changes, before its effective realisation can be achieved with only a standard inverter bridge and a very small overall capacitance. Design of this capacitance and its comparison with passive decoupling have then been analysed, before testing the MSSI in experiments. Results obtained have verified the MSSI as an enhanced single-phase inverter with both buck and boost abilities while using no extra switches.