In multilevel inverters, unused energies are created due to the asynchronous use of the input DC sources. when the input DC sources are replaced by renewable systems such as photovoltaic arrays, some of the input energies remain unused. This paper presents a new multilevel inverter topology that can harvest the unused energies and return them to another output which leads to the harvest of the maximum input energy. The harvest of maximum energy (HME) based multilevel inverter structure consists of two terminals. One is connected to AC-load and another is joined to DC-load or rechargeable batteries. Another merit of the proposed multilevel inverter is that the number of its switches is comparable to other structures where unused energies cannot be harvested. Selective harmonic elimination (SHE) has been used as the switching strategy in the proposed multilevel structure. To verify the performance of the HME-based multilevel inverter topology, the experimental results for a type seven-level inverter were performed by the TMS320F28379D DSP.

This paper presents a new symmetrical switched-capacitor (SC) multilevel inverter topology which can convert the input DC voltage to a step-up multilevel AC waveform on the load. This proposed multilevel inverter consists of one T-type and several cross-capacitor modules. The structure of the generalized multilevel inverter is such that the peak inverse voltage (PIV) remains constant as the number of crosscapacitor modules increases which leads to reduce the total standing voltage (TSV) of the switches and cost function compared to other traditional topologies. The introduced structure can inherently generate the positive, negative, and zero voltage levels on the output without the back-end H-bridge section. The capacitor's voltages in the T-type and cross modules are inherently balanced, simplifying the control system under the nearest level control (NLC) switching strategy. To verify the performance of the proposed topology, several simulations and experimental results for a type 13-level inverter are provided by MATLAB and TMS320F28379D DSP, respectively.