Design and analysis of novel optimal harmonic elimination strategy based on MOPSO to obliterate low‐order harmonics of odd‐nary cascaded transformers‐based multilevel inverter

Abstract

Creating a high‐step staircase sinusoidal voltage taking into account of low number of switches is recognized as a significant challenge ahead of inventors of power electronics. This paper suggests a maiden cascaded transformer‐based multilevel inverter to effectively develop and solve the abovementioned challenge. Hence, via appending the bidirectional switches to the capacitors of submultilevel inverter as well as low‐frequency transformers, the proposed inverter structure can flexibly operate as so‐called “odd‐nary asymmetrical multilevel inverter.” From the perspective of low‐order harmonics produced by all inverter structures, apart from inverter type, it is essential that an effective strategy to be implemented to eliminate these harmonics. Toward this subject, kerf‐style Selective Harmonic Elimination Pulse Width Modulation (SHEPWM) has been scheduled as an optimization problem. Because of nature of multiobjective state of the problem, application of the multiobjective optimization technique is inevitable. Considering significant performance of Multi Objective Particle Swarm Optimization (MOPSO) for solving the nonlinear objectives, the elimination of fifth, seventh, and 11th harmonics is formulated by relevant fitness functions based on MOPSO. Putting it all together, the relevant analytical study accompanying both the simulation and experimental results has transparently verified the performance of the proposed multilevel inverter. Furthermore, elimination of all three designated low‐order harmonics, ie, fifth, seventh, and 11th harmonics using MOPSO‐based kerf‐style SHEPWM strategy has been well confirmed.

Robust fractional‐order super‐twisting sliding mode control to accurately regulate lithium‐battery / super‐capacitor hybrid energy storage system

“…As for the multilevel inverter part of the DVR, many different structures have been introduced to participate in the power quality improvement. As a case in point, an innovative asymmetric odd‐nary MLI is proposed for DVR to provide a high‐step staircase sinusoidal voltage with low switch counts to reduce its cost‐price, 24 and then its harmonic components have been significantly diminished using kerf‐style selective harmonic Scheme 25 . In addition, a half‐cascaded based multilevel inverter along with brain emotional learning based intelligent controller is proposed for DVR to ride‐through the disturbance conditions and meet the grid codes 26 .…”

Comparative analysis of switching angle calculation methods for multilevel inverters

“…The inverters have become an integral part of various systems such as motor drives, renewable energy integration to grid, and power system apparatus like FACT devices, etc. because they impart better control ability to the system 1‐11 . An inverter is used with some control technique to obtain desired output voltage.…”