Performance analysis and control of a novel 7-level active neutral point clamped (ANPC) topology

This paper introduces a novel 7-level active neutral-point clamped (ANPC) switched capacitor multilevel inverter (SCMLI) with voltage-boosting capabilities. The proposed converter can produce seven levels and a voltage boosting of 1.5 times with a single dc source. For boosting the voltage, two self-balanced switched capacitors and two dc link capacitors with active neutral point are used with nine switches. For controlling the output voltage, the level-shifted modulation technique and modified nearest level control technique is used. The performance of the converter is evaluated with both modulation techniques. The operation of the proposed SCMLI and the design of capacitors for the proposed circuit is discussed in detail. The proposed topology can eliminate the leakage current and has reduced voltage stress across switches which makes it suitable for solar photovoltaic applications. The proposed converter is compared with some other recently introduced converters in terms of voltage gain, the number of components used, and the voltage stress across the switches. For verifying the performance of the proposed circuit, the experimental and simulation results are presented in the paper. The experimental results closely agree with the simulation and theoretical studies. The total harmonic distortion (THD) in the output voltage and efficiency is compared with both modulation techniques. 2023 The Authors. IET Power Electronics published by John Wiley & Sons Ltd on behalf of The Institution of Engineering and Technology.Scopu

Artificial jellyfish search algorithm-based selective harmonic elimination in a cascaded h-bridge multilevel inverter

This paper used an artificial jellyfish search (AJFS) optimizer suitable for selective harmonic elimination-based modulation for multilevel inverter (MLI) voltage control application. The main objective was to remove the undesired lower-order harmonics in the output voltage waveform of an MLI. This algorithm was motivated by the behavior of jellyfish in the ocean. Jellyfish have the ability to find the global best position where a large quantity of nutritious food is available. The paper applied AJFS algorithm on five, seven, and nine levels of CHB-MLI. The optimum switching angle was calculated for the entire modulation range for the desired lower-order harmonics elimi-nation. The problem formulated to achieve the objective was solved in a MATLAB environment. The total harmonic distortion (THD) values of five-, seven-, and nine-level inverters for various modulation indexes were computed using AJFS and compared with the powerful differential evolution (DE) algorithm. The comparison of THD results clearly demonstrated superior THD in the output of CHB-MLI of the AJFS algorithm over DE and GA algorithm for low and medium values of modulation index. The experimental results further validated the better performance of the AJFS algorithm.</p