Summary Induction motors are typically promoted in industrial applications by adopting energy‐efficient power‐electronic drive technology. Multilevel inverters (MLI) have been widely recognized in recent days for high‐power, medium‐voltage‐efficient drives. There has been vital interest in forming novel multilevel inverters with reduced switching elements. The newly proposed reduced‐switch five‐level inverter topology extends with fewer switches, low dv/dt stress, high efficiency, and so on, over the formal multilevel inverter topologies. The multilevel inverter's reputation is greatly affected due to several faults on switching elements and complex switching sequences. In this paper, a novel fault identification process is evaluated in both healthy and faulty conditions using discrete‐wavelet transform analysis. The discrete wavelet transform utilizes the multi‐resolution analysis with a feature extraction methodology acquired for fault identification over the classical methods. A novel fault identification scheme is implemented on reduced‐switch five‐level MLI topology using the Matlab/Simulink platform to increase the drive system's reliability. The effectiveness of simulation outcomes is illustrated with proper comparisons. The proposed topology's hardware model is implemented using a dSPACE DS1103 real‐time digital controller and the results of the experiment are presented.

In order to improve the voltage levels and reducing the total harmonic distortions (THDs), a symmetrical hybrid multilevel converter (MLC) topology with different sources, that is, a photovoltaic (PV) source and a constant DC source for electric drive applications are proposed in this article. The presented topology comprises of distinctive converters for each phase, is coupled to a 3∅ asynchronous motor. The two converters are operated with low voltage, high frequency, and high voltage, which are fundamental to increase the output voltage. A modified phase‐shifted pulse width modulation technique helps to control the power of semiconductor devices. The reduced component count and THD of the hybrid MLC are assessed using the conventional topologies. It was found that the THD is 15.10% in voltage and 1.97% in current for the proposed system and exhibits better performance in relative to the PV source. Finally, the simulation outcomes accompanied by comparative analysis are also discussed in the article.

The multilevel inverter-based drive system is greatly affected by several faults occurring on switching elements. A faulty switch in the inverter can potentially lead to more losses, extensive downtime and reduced reliability. In this paper, a novel fault identification and reconfiguration process is proposed by using discrete wavelet transform and auxiliary switching cells. Here, the discrete wavelet transform exploits a multiresolution analysis with a feature extraction methodology for fault identification and subsequently for reconfiguration. For increasing the reliability, auxiliary switching cells are integrated to replace faulty cells in a proposed reduced-switch 5-level multilevel inverter topology. The novel reconfiguration scheme compensates open circuit and short circuit faults. The complexity of the proposed system is lower relative to existing methods. This proposed technique effectively identifies and classifies faults using the multiresolution analysis. Furthermore, the measured current and voltage values during fault reconfiguration are close to those under healthy conditions. The performance is verified using the MATLAB/Simulink platform and a hardware model.

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