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Summary In electric vehicles (EVs), considerable battery cells are cascaded in series for motor driving to improve the output voltage. The series combination of battery cells causes challenges like isolation of faulty cells, voltage unbalance, and slow charge equalization. Therefore, state‐of‐charge (SOC) and voltage equalization circuits are often used in industries to protect the battery cells. A nine‐level inverter circuit with a double voltage boost is proposed to reduce the above issues based on the switch‐capacitor (SC) principle. Unique features like self‐balancing, voltage boosting are attained, which cannot be achieved through traditional inverters. The proposed topology can operate at a wide range of modulation indices (ma) to produce different voltage levels. The absence of a back‐end H‐bridge in the proposed circuit offers low voltage stress across the semiconductors. The operating principle, capacitor sizing, and modulation approach are presented. Further, experimental tests are conducted at different loading conditions to verify the performance of the proposed circuit.

Summary A novel multilevel inverter (MLI) configuration with the hybrid switching technique is presented in this paper. The proposed MLI consists of the H‐bridge combination with unidirectional switches, half‐bridges, and transformers. The suggested MLI with the additional cascaded connection increases to higher voltage levels. The number of employed components in this topology is drastically minimized. Therefore, the complexity, cost, and volume of the proposed topology are also reduced. The operation of the suggested topology is tested through the improved novel switching technique. This modulation method reduces the total harmonic distortion (THD) and produces high root mean square (RMS) voltage. Further, a comprehensive comparison with the recent MLI topologies is performed to validate the merits of the suggested inverter. Simulation and experimental results verify the suggested topology performance using the new modulation technique at different loading conditions and modulation indices.

Summary Due to their remarkable performance, capacitor‐based inverters have recently gained attention. Hence, a new capacitor‐based multilevel inverter is presented in this paper for electric and hybrid electric vehicle (EV and HEV) applications. EV systems are quite well for their use of two‐level inverters; however, the generated load voltage comprises substantial undesirable harmonic content. It is regarded as one of the most efficient methods since replacing a two‐level inverter with a multilevel inverter improves the power quality despite significantly reducing total harmonic distortion. Therefore, the recommended filter dimension will also be minimized. A flurry of reliability concerns has arisen due to the increased number of devices, circuit complexity, and stress on the circuit devices. A nine‐level voltage waveform is created with only ten IGBTs, a DC‐Source, and two capacitors. In the proposed nine‐level inverter, the capacitor voltage is balanced utilizing a simple control approach to regulate the flying capacitor (FC) voltages actively. Here described a simple logic gate‐based pulse‐width modulation technique that ensures capacitor power balancing. The proposed inverter operation and capability are validated by experimental results derived from a laboratory prototype. Finally, by contrasting the new and standard inverter topologies, the virtues of the suggested architecture by the number of devices and price of the equipment are highlighted, and it is a simpler structure that requires less space and footprint area.

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