This article describes a modified structure 9-level inverter (MS9LI) with a dual dc link and eight switches. The dual dc links are different dc voltage sources with a 1:3 ratio. To generate high-quality nine-level output, the alternative phase opposition and disposition pulsewidth modulation (APODPWM) technique has been used. Most reported reduced device multilevel inverters (MLIs) include several underutilized dc sources and much more active switches. The designed MS9LI is more efficient since it uses fewer conducting switches. The proposed configuration furthermore does not need a backend H-bridge, and voltage stress is not more than the input dc voltage. A series connection of the proposed configuration can also be used to extend the topology. To prove the superior performance of the proposed MS9LI configuration, a detailed comparison with the foremost configurations in terms of the essential number of sources, switches, and drivers is made. In order to confirm the viability and functionality of the MS9LI configuration, various simulation and experimental findings are presented.

This paper presents different multi-carrier unipolar trapezoidal pulse width modulation strategies for a reduced switch asymmetrical multilevel inverter. The different strategies are phase disposition, alternative phase opposition and disposition, and carrier overlapping and variable frequency that involve triangular waves as carriers with a unipolar trapezoidal wave as a reference. The reduced switch, asymmetrical multilevel inverter operation was examined for generating the seven-level output voltage using Matlab/Simulink 2009b and the results were verified with a real-time laboratory-based experimental setup using a field-programmable gate array. Different parameter analyses, such as total harmonic distortion, fundamental root mean square voltage, and distortion factor, were analyzed with different modulation indices to investigate the performance of the selected topology. Unipolar trapezoidal pulse width modulation provides a higher root mean square voltage value.

The conventional multilevel inverter necessitates more active switching devices and high dc-link voltages. To minimalize the employment of switching devices and dc-link voltages, a novel topology has been proposed. In this paper, a novel minimum switch multilevel inverter is established using six switches and two dc-link voltages in the proportion of 1 : 2. In addition, the proposed topology is proficient in making seven-level voltages by appropriate gate signals. The PWM signals were produced using several inverted sine carriers and a single trapezoidal reference. When compared to other existing inverters, this configuration needs fewer components, as well as fewer gate drives. Furthermore, this module can generate a negative level without the use of a supplementary circuit such as an H-Bridge. As a result, overall cost and complexity are greatly reduced. The proposed minimum switch multilevel inverter operation is validated through simulations followed by experimental results of a prototype.

The switched reluctance motor (SRM) has more salient features such as high starting torque, isolation of phase windings, and no rotor windings. Similarly, a permanent magnet brushless direct current (BLDC) motor possesses numerous merits such as high power density, and low torque ripple. However, this SRM and permanent magnet BLDC motor suffer from torque ripple and cogging torque, respectively. Therefore, this research article enriches the design procedure and characteristics of a 3-kW, 60-V hybrid reluctance motor with minimum torque ripple and vibration. Furthermore, this proposed motor is modeled and analyzed with various laminating core materials such as 47F165, Arnon 7, M420-50D, M300-35A, 36F155, and M-27 24Ga for identifying the superior material by considering the relevant parameters such as losses and torque. In the proposed doubly salient motor, a vibration analysis is also performed to predict its natural frequency. A laboratory arrangement is implemented to examine the proposed motor at no-load conditions. Then no-load current and vibration frequency were measured by a digital storage oscilloscope and accelerometer, respectively. These experimental outcomes are compared with finite-element analysis and analytical equations to validate findings.

The article presents a seven-level reduced switch asymmetrical multilevel inverter with two different methods of pulse width modulation (PWM) techniques. Phase disposition (PD) PWM and hybrid variable-frequency phase disposition PWM (HVFPD-PWM) are the two different PWM methods for making the quality of output voltage waveform. In the first method, the unipolar sine reference with triangular carriers is used. In the second method, the hybrid unipolar reference (sinusoidal with trapezoidal) is proposed with variable frequency carriers to generate the switching pulses for asymmetric multilevel inverter (MLI). The main objective of this proposed method is to reduce the total harmonic distortion in the output voltage waveforms. A comprehensive comparison of the proposed HVFPD-PWM and the conventional PD-PWM with asymmetrical seven-level inverter is presented to show the enriched performances of the proposed method. The performance and viability of the suggested PWM are evaluated through simulation and experimental results using an asymmetrical seven-level inverter. The total harmonic distortion for the proposed PWM method (16.95%) is significantly reduced as compared with the conventional PWM method (18.01%) at the modulation index of one.

The permanent magnet synchronous motor (PMSM) has a more efficiency, high torque density, and high power density, but it suffers from torque ripple. This article describes the electromagnetic (EM) behavior of M19 29Ga material assists PMSM for 310 V, 5 A, and 1500 r/min. In addition, various materials as Losil 34050, Arnon 5, 50M290, M19 USS Transformer 72–29 gauge, and TR80 USS Transformer 80–29 gauge incorporated PMSM and which material has superiority, and with the superiority kept constant, changed the various magnet materials. The EEC 26-T350, MQP-14–12 835995, N45M, Recoma 22, Samarium Cobalt 20/30, Vacodym 890TP, and Vacomax 240 incorporated PMSM also investigated for EM finite-element analysis. The results of this study of the variable as torque ripple forecast the highest torque ( $T_{\mathrm {max}})$ , lowest power output ( $T_{\mathrm {min}})$ , and overall torque ( $T_{\mathrm {avg}})$ . The superior motor among various materials unified PMSM by its ripple and field characteristics. The outcomings of the modeled motor are validated with numerical equations.