A control mechanism to compensate nonlinearity of discontinuous modulation based grid-connected differential-mode Ćuk inverter

The differential-mode Ćuk inverter (DMCI), with outstanding features, has a good chance to replace the conventional topologies in grid connected application for renewable energies. Two modulation schemes have been introduced for the inverter in literature. Discontinuous-modulation scheme (DMS) uses one module in each half line cycle, whereas the continuous-modulation scheme (CMS) continuously uses both the inverter modules. The DMS suits the switched mode power supply applications because of better efficiency and lower device ratings. But, the DMS shows nonlinear control-to-output relation, which translates to more current distortion or need for complicated controller in grid-connected mode. This paper introduces a static-linearized DMS (SLDMS) scheme. It mitigates the control-to-output nonlinearity of the DMCI. It uses the input and output voltages as feed forward to generate the needed modulating signal. The results demonstrated in this digest provide the validity to the new mechanism.