Cascaded Multilevel Inverter Research Articles

Retraction Note: Artificial intelligent controller-based power quality improvement for microgrid integration of photovoltaic system using new cascade multilevel inverter

Retraction Note: Artificial intelligent controller-based power quality improvement for microgrid integration of photovoltaic system using new cascade multilevel inverter

A Novel NR-DA-Based ANN for SHEPWM in Cascaded Multilevel Inverters for Renewable Energy Applications

Harmonics is the major power quality problem caused by nonlinear devices, leading to malfunction or operational halt of the system. Low-order harmonics increase vibration and heat generation in motors. Therefore, controlling harmonics in the output waveform is the prime target for industrial applications to avoid economic loss. Selective harmonic elimination pulse width modulation (SHEPWM) is one of the techniques used for eliminating or minimizing selected harmonics in the output voltage waveform. This paper utilizes the Newton-Raphson method and Dragonfly Algorithms to calculate optimum switching angles for a Cascaded H-bridge Multilevel inverter (CHBMLI). The algorithms use non-linear equations to calculate the Switching Angles of MLI. The Dragonfly algorithm requires several iterations to reach an optimum solution. For complex problems, this algorithm becomes computationally expensive and time-consuming. A lookup table addresses the limitation by offline training an Artificial Neural Network (ANN) to generate the optimum switching angle for a given modulation index. Neural Fitting Tool in MATLAB software is used to train the ANN model. The simulation is performed using MATLAB SIMULINK software for both 5-level and 7-level CHBMLI configuration. The Dragonfly algorithm-based ANN achieves THD 8.84% when the modulation index (M) equals 0.8 for a 7-level inverter and THD 14.91% for a 5-level inverter and effectively minimizes third and fifth-order harmonics.

A New Cascaded Multilevel Inverter for Modular Structure and Reduced Passive Components

In high-power applications, achieving adequate power quality in power converter design is accomplished by utilizing multilevel inverters instead of using two-level and three-level inverters. The device generates a sinusoidal output voltage, which results in reduced total harmonic distortion and lower voltage stress on the switches and leads to lower electromagnetic interference, making it suitable for use in renewable energy applications. However, to illustrate the advantages mentioned above, a significant number of switching devices and DC sources are necessary while raising the voltage levels. This article proposes an asymmetrical voltage generation method, which operates in a ratio of 1:5 and generates 25 levels using 11 power switches. The topology is modular in structure, and each module has a lower component count, which significantly reduces the overall cost. The proposed topology is capable of generating negative output voltage levels without the use of an H-bridge configuration, where only three switches are used to generate any voltage levels. The functionality of the developed module is amended by fixing different voltage values in DC sources. This article also presents a comprehensive examination of the circuit and the functioning of various voltage levels. The advantages of the proposed inverter have been demonstrated by comparative research with the currently existing MLI topologies. Ultimately, both the simulation and experimental findings validated the practical capabilities.

Evaluation of a multiphase cascaded H-bridge inverter for induction motor operation

Multi-phase systems are becoming more popular for applications requiring high power and precise motor control, even if single-phase AC power is still frequently utilized in households and some enterprises. While both systems have benefits over single-phase, there are trade-offs associated with each. Because of its balanced operation and effective power transfer, the three-phase (3-Φ) system is the most widely used multi-phase system. Nevertheless, different phase values can be investigated for particular applications where reducing torque ripple and harmonic content is essential. Using odd numbers of phases (such as 5-Φ) that are not multiples of three is one method. This design has the ability to reduce torque ripple by producing a more balanced magnetic field as compared with even-numbered phases. But adding more phases also makes the system design and control circuitry more complex. Systems with five phases (5-Φ) provide a compromise between performance and complexity. Applications such as electric ship propulsion, rocket satellites, and traction systems may benefit from their use. Nevertheless, choosing a multi-phase system necessitates carefully weighing the requirements unique to each application, taking into account elements like cost, power transmission, control complexity, and efficiency. The increasing popularity of electric vehicles and renewable energy technologies has led to the need for inverters in current electric applications. Conventional inverters provide square wave outputs, which cause the drive system to become noisy and cause harmonics. Multi-phase multilevel inverters can be used to enhance inverter functioning and produce an improved sinusoidal output. This study focuses on an induction motor drive powered by a five-phase multilevel cascaded H-Bridge inverter. With less torque and current ripples in the motor rotor, the power conversion harmonics are reduced and the switching components of the inverter are under less stress. However, in comparison to traditional inverters, it does require a greater number of legs. Because the switches needed for the cascaded H-Bridge inverter are less expensive in five-phase systems, they are favoured over higher phase orders. Furthermore, the suggested inverter removes 5th order harmonics, something that is not possible with traditional inverters. A five-phase induction motor appropriate for variable speed driving applications is also suggested by this research. Lastly, utilizing pulse width modulation (PWM) converters and an FPGA controller, an experimental study is carried out to assess the dynamic performance of the suggested induction motor drive. Particular attention is paid to the In-Phase Opposition Disposition (IPD) PWM technique.

Drive Control using Multilevel Inverter for Electric Vehicle Application: A Hybrid SCSO-SNN Technique

This manuscript proposes a hybrid method for drive control using a multilevel inverter (MLI) for electric vehicle (EV) applications. The proposed technique is the joint execution of spiking neural network (SNN), and sand cat swarm optimization (SCSO), hence it is named as SCSO-SNN technique. The primary goal of the proposed technique is to improve the speed tracking performance and, energy efficiency and lessen the torque ripple of the EV. The set of control signals is generated by SCSO and the SNN is used to forecast the optimal control signal of the cascaded multilevel inverter (CMLI). The proposed technique is implemented in the MATLAB software and is evaluated their performance with various present methods. The results show that the proposed method can achieve better performance than current techniques based on speed tracking, energy efficiency, and torque ripple. The proposed method enhanced the total efficiency of the system (96%) and reduced the torque ripple (0.5%) when contrasted with current techniques like Genetic Algorithm (GA), Spotted Hyena Optimizer (SHO), Particle Swarm Optimization (PSO). The proposed method shows a mean of 1.269, a median of 1.212, and a standard deviation of 0.015, indicating high stability and consistency. It also demonstrates lower switching losses (0.159 W) and conduction losses (0.370 W) compared to existing methods, underscoring its superior energy efficiency and effectiveness.

Review of Multilevel Level Inverter Using Different Topologies

This paper provides a concise overview of various multilevel inverter (mli) topologies. The conventional two-level voltage source inverter (vsi) necessitates a filter to generate sinusoidal output waveforms, which can be challenging at high frequencies due to switching losses. To address this issue, multilevel inverters offer lower switching frequencies and reduced total harmonic distortion (thd), eliminating the need for filters and large transformers. Moreover, a few advantages of mli inverters are reduced switching losses, better performance at high switching frequencies, and higher power quality (almost pure sinusoidal). Nevertheless, adding to the complexity of the system is the requirement for each switch to have its own gate driver in order to perform mli. Thus, it's imperative to decrease the mli's number of switches. In order to reduce the number of switches needed, this paper reviews some of the various current topologies. Applications such as voltage regulation, var compensation, harmonic filtering in power systems, and user interface for renewable energy have led to the development of cascaded h-bridge multilevel inverters. For solar applications, a modified cascaded h-bridge multilevel inverter (mli) is used. Cascaded h-bridge topology multilevel inverter will aid in reducing the number of switches. Comparing this concept to other multilevel inverters, the switching complexity is reduced.

Fault Diagnosis of Asymmetric Cascaded Multilevel Inverter using Ensemble Machine Learning

Fault Diagnosis of Asymmetric Cascaded Multilevel Inverter using Ensemble Machine Learning

Design Procedure of Cascaded Multilevel Inverter for High-Power Amplifier in SONAR System

In recent years, there has been a trend toward expanding the operating frequency range and increasing the output power of Sound Navigation and Ranging (SONAR) systems to enhance their acoustic detection capabilities. However, due to this increase in operational power, the electrical capacity of amplifiers for SONAR system operation also increases, necessitating High-Power Amplifiers. When configured with a single amplifier, as in conventional methods, the volume of amplifiers increases due to volumetric increases in heat dissipation, components, and windings. These issues are detrimental to SONAR amplifier installation, mobility, maintenance, and equipment lifespan due to stress on individual components. Additionally, amplifiers for SONAR systems are comprised of power conversion devices, transformers for LC filters and matching, necessitating consideration of LC filters and matching transformers for enhancing voltage quality and efficiency to improve amplifier performance transmitted to SONAR transducers. However, previous research has focused on single-amplifier design methods, neglecting such considerations. Therefore, this paper proposes a design technique that overcomes the drawbacks of using the conventional design method by configuring multiple H-bridge inverters in a cascade format and utilizes one of the optimization algorithms, Particle Swarm Optimization (PSO), to derive amplifier design techniques that optimize component parameters for enhancing high-capacity amplifier performance. Subsequently, theoretical analysis, simulations, and experimental results comparing the proposed high-power amplifier design method with conventional single-amplifier design methods demonstrate similar error rates in operational frequency bands.

An intelligent approach for cascaded multi-level inverter (CMLI) with grid-connected hybrid system

An intelligent approach for cascaded multi-level inverter (CMLI) with grid-connected hybrid system

Phase modulation of carriers for cascaded multilevel three-phase inverters

Cascaded multilevel three-phase inverters are commonly used in industrial applications and the quality of these inverters is highly dependent on the modulation techniques. The common mode voltage is one of the factors affecting the quality of the three-phase inverter output voltage. This paper proposes a carrier phase modulation method for cascade multilevel inverters to reduce the magnitude of common-mode voltage magnitude and harmonics. In the proposed method, the carrier phase modulator is considered as an adaptive controller and the phase of carrier is completely controlled by the magnitude of control signal. The phase modulation has a high immunity to the noises compared with the modulations of frequency and amplitude because it is difficult for noises to intrude into the phase of carrier. In addition, the algorithm of carrier phase modulation is simple and requires little memory. Moreover, the number of switching commutations of the proposed method also reduces significantly. Simulation and experiment results based on a cascaded five-level three-phase inverter system have confirmed the effectiveness of the proposed method compared with that of the popular methods using unmodulated carriers such as phase disposition (PD) and phase opposite disposition (POD).

Solar Fed 15 Level Cascaded Multilevel Inverter with ANFIS Control Strategy for Enhancement of Power Quality

Solar PV energy conversion systems suffer from degraded power quality issues because of harmonics in the system. In order to eliminate harmonics, this paper focuse on a solar-powered 15-level cascaded inverter. A number of controllers such as PI, Fuzzy Logic Neural Network and ANFIS are used in this study in order to manage the PWM frequency (Proportional Integral, Fuzzy Logic, NN and Adaptive Neuro Fuzzy Inference System, respectively). A PV-fed 15-level cascaded multilevel inverter for power quality improvement will be developed by using an ANFIS controller. The suggested ANFIS controller has a lower harmonic distortion than conventional controllers; hence the quality of the power improves. The PI, FL, ANN, and ANFIS controllers simulated results are analysed in MATLAB.

Notice of Violation of IEEE Publication Principles: A Hybrid ANFIS/ABC-based Online Selective Harmonic Elimination Switching Pattern for Cascaded Multi-level Inverters of Microgrids

Notice of Violation of IEEE Publication Principles A Hybrid ANFIS/ABC-based Online Selective Harmonic Elimination Switching Pattern for Cascaded Multi-level Inverters of Microgrids, by H. R. Baghaee; M. Mirsalim; G. B. Gharehpetian; H. A. Talebi; A. Niknam-Kumle, in the IEEE Transactions on Industrial Electronics After careful and considered review of the content and authorship of this paper by a duly constituted expert committee, this paper has been found to be in violation of IEEE’s Publication Principles. This authorship of this paper was revised without providing attribution to, or permission from, the coauthors of an earlier version of the manuscript. Alireza Niknam-Kumle was responsible for removing the original coauthor names and replacing them with new coauthors, and then resubmitting the content in a new manuscript to IEEE Transactions on Industrial Electronics Due to the nature of this violation, reasonable effort should be made to remove all past and future references to this paper. Control of electronically-coupled distributed energy resources and topology/switching strategy of power converters have the essential roles to provide high quality power for microgrids including unbalanced and nonlinear loads. Multi-level inverters (MLIs) are used to act as high quality converters with more conversion efficiency, and less switching-frequency/switching-losses. Nevertheless their nonlinearity, complexity, and solvability features of selective harmonic elimination strategy that has affected its industrial applications, it can provide desirable output waveform by keeping fundamental component in its desired value as well as eliminating/minimizing of low-order harmonics. This paper presents adaptive neuro-fuzzy inference system (ANFIS) as a switching angle estimator for harmonic optimization problem in cascade MLIs, which is trained based on the database including optimal switching angles obtained for inverter with non-equal DC sources by artificial bee colony (ABC) algorithm. The reliable search ability, accuracy and convergence time of ABC have been compared with particle swarm optimization algorithm. Also, performance of ANFIS is compared with artificial neural network based on correlation coefficient and root mean square error. Simulation results, experimental tests and real-time simulations reveals the effectiveness of proposed estimator for online elimination of low-order harmonics of MLIs in microgrids and its superiority over other methods.

A Symmetric Multi-Level Cascaded H-Bridge Inverter for Renewable Energy Integration

The advanced multi-level cascaded H-Bridge inverter system described in this paper is novel and intended for effective integration of renewable energy sources. Phase-displacement pulse width modulation (PD-PWM) control has been employed in the proposed five-level topology to produce output voltage with better quality. The system incorporates proficient filtering methods with a low total harmonic distortion (THD) desired outcome. With a stable output of 230 V at 50 Hz and a 2.3 kW capacity, the inverter system has been satisfied the exacting IEEE 519 standards for power quality. The MATLAB/Simulink is implemented to simulate and model the entire system, exhibiting its superior performance in terms of harmonic reduction and grid compliance. The innovative design offers a dependable respond to for integrating renewable energy, ensuring smooth and high-quality power injection into the grid.

A hybrid control topology for cascaded H-bridge multilevel inverter to improve the power quality of smart grid connected system: NBO-RERNN approach

This manuscript proposes a hybrid control technique for the grid-connected photovoltaic (PV) generation system with a cascaded multilevel inverter (CMLI). The proposed hybrid approach integrates the Namib beetle optimization (NBO) and recalling-enhanced recurrent neural network (RERNN) approach, known as the NBO-RERNN technique. The cascaded multilevel inverter (MLI) is intended to increase the optimum control signal using the proposed controller. The cascaded multilevel inverter (MLI) is designed by using the minimum count of switches. The key purpose of the proposed approach is to improve power regulation or maximal solar energy conversion system (SECS) and to achieve good power quality (PQ) of the system. The proposed NBO technique generates the optimum control signal dataset offline. Based on the fulfilled dataset, the RERNN generates the best CMLI control signals inonlinemanner. The resultant control signals are used to regulate cascaded multilevel inverter insulated gate bi-polar switches (IGBT). For this purpose, the proposed NBO-RERNN control topology defines converter switching states by modeling generation system operating modes. The parameter variations of the system and external disturbances are mitigated, and the load demands are fulfilled optimally by using this control technique. The NBO-RERNN control topology is implemented in MATLAB, and its performance is compared with existing approaches. The simulation reveals that the proposed method has lower THD than the existing one.

A Novel Multiport Embedded DC Current Flow Controller Based on a Cascaded Multilevel Inverter

A Novel Multiport Embedded DC Current Flow Controller Based on a Cascaded Multilevel Inverter

Improved power quality for photovoltaic grid integration power system using an intelligent controller fed SL–SC boost converter supplied reduced switch cascade multilevel inverter

Improved power quality for photovoltaic grid integration power system using an intelligent controller fed SL–SC boost converter supplied reduced switch cascade multilevel inverter

A New Level Shifted Carrier Based PWM Technique for a Cascaded Multilevel Inverter Based Induction Motor Drive

The pulse width modulation (PWM) techniques are becoming the game changer for multi-pulse power converter fed multilevel inverter-based induction motor drive (IMD) due to their significant impacts on power quality. In this paper, a new level shifted carrier-based PWM technique is proposed for a 5-level cascaded H-bridge (CHB) multilevel inverter driven by a 36-pulse ac-dc converter based IMD. To meet the power quality demand of IEEE-519 at grid side, a modular transformer is used, and the transformer is coupled to form a 36-pulse ac-dc converter. A 5-level CHB multilevel inverter is utilized on the motor side, which uses the proposed carrier based PWM technique for switching action to ensure superior performance of the IMD. The proposed PWM technique is named as third-harmonic injected inverted sinusoidal carrier PWM (THI2SCPWM), which utilizes 3 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">rd</sup> harmonic injection principle with inverted sinusoidal signal to form the proposed carrier signal. The 5-level CHB inverter used in the IMD shows less power loss and total harmonic distortion (THD) with the proposed THI2SCPWM technique. Moreover, the IMD with the THI2SCPWM shows low stator voltage THD, stator current THD, and smooth dynamic response. Apart from these, the THI2SCPWM mitigates the torque ripple of the IMD. The motor drive system with the THI2SCPWM technique is modeled and its performance is simulated on MATLAB/Simulink environment. A scaled down experimental setup is utilized to validate the superiority of the proposed PWM technique.

Comparison of Pulse Width Modulation Techniques for Diode-Clamped and Cascaded Multilevel Inverters

Multilevel inverter technology has become the most significant method of energy conversion from DC to AC for uninterrupted power supply. The quality of the power supply depends on the appearance of harmonics, which is considered a problem that needs to be overcome. This paper demonstrates the use of a new modulation technique to reduce the harmonics in both diode-clamped and cascaded multilevel inverters, examining its Total Harmonic Distortion (THD) compared to other PWM methods. Simulations were carried out in MATLAB/Simulink for five-level diode-clamped and cascaded multilevel inverters. The simulation results of both multilevel inverters using the sinusoidal PWM, modified reference PWM, modified carrier PWM, and modified reference and modified carrier PWM methods showed that the latter had the best THD performance for both inverter types, especially for the cascaded multilevel inverter.

A Matching Scheduling Control Strategy Based on Modulation Wave Reconstruction for the Single-Phase Photovoltaic Cascaded Multilevel Inverter

The single-phase cascaded multilevel inverter (CMI) becomes an attractive solution for grid-connected photovoltaic (PV) power generation owing to its several advantages, such as the scalable modularity, the ability to reach the component level maximum power point tracking (MPPT), and the multilevel output voltage. However, the PV power of each H-bridge (HB) is uneven due to unequal illumination and partial shading of the PV panels, which may lead to overmodulation and further deteriorate the power quality of the grid-connected current. Existing methods to address this issue have not considered the effects on various operating conditions, and their application scope is limited. Therefore, this paper proposes a matching scheduling control strategy based on modulation wave reconstruction (MSMR). The relatively optimal modulation waveform of each HB is reconstructed scheduledly to match its PV power by detecting the operating conditions. Meanwhile, the PV power of each HB is adjusted to improve the ability to cope with the power unevenness. Finally, the proposed strategy is validated on a down-scaled experimental test bench.

Grid Connected Photovoltaic System with Modified Quasi Z-Source Based Cascaded Multilevel Inverter (MQZS-CMLI) Using RENCO Approach

This paper introduces a Multi-Level Cascade Inverter (MLI) based on Enhanced Quasi-Z Source Inverter (MQZSI) to connect photovoltaic (PV) systems based on the proposed method. Usually the interface among PV power supply and load is completed with MQZS-CMLI. In this paper, the proposed control scheme is comprehensive implementation of Recalling Enhanced Recurrent Neural Network (RERNN) and Quasi-Opposite Chemical Reaction Optimization (QOCRO) named as RENCO. The main objective of proposed method is to decide the efficiency of the PV system by the maximal power extraction. Here, MQZS-CMLI’s modeling design contains suitable number of components, other than their capacitors and semiconductors comply with low-voltage stress. It is improved for providing that maximum power of the PV power generation system. At first, the goal function is described according to the parameters and limitations of controller (like voltage, current, power, modulation index, so on). These parameters apply to recommend RENCO technology input. The proposed RENCO technology improves voltage distribution, power transmission, and minimizes power fluctuations while sharing power with load. The proposed MPPT-based technology ensures that the maximum power is provided to load. The proposed method adjust the duty cycle of MQZS-CMLI and reduces the modulation load. Finally, the proposed technology is executed on the MATLAB/Simulink platform, and its output efficiency is compared to existing systems under dissimilar load circumstances.