Hybrid Modulation Research Articles

Efficient n-M-PAWM hybrid modulation scheme for high data transmission in visible light communication system

Visible-Light Communications (VLC) is a new wireless communication technology, which has attracted particular attention as a promising solution for very high speed 5G, and 6G wireless networks in indoor environments. Intensity modulation (IM) is considered as the most appropriate modulation technique for VLC. This paper proposes to study a visible light communication (VLC) system with intensity modulation and direct detection (IM/DD). A channel modulation scheme is designed and encoded either in L-level pulse amplitude modulation (PAM), pulse position modulation (PPM), or pulse width modulation (PWM). In order to improve transmission efficiency, Hybrid Pulse Amplitude Position Modulation (PAPM) and Pulse Position Width Modulation (PPWM) are proposed in optical wireless communication (OWC), especially in VLC technologies. In this Paper, we propose a novel combination between PAM and PWM modulation schemes, called Pulse Amplitude Width Modulation (PAWM). The proposed modulation decreases the bit error ratio (BER) of VLC system, approximately 10−8 at Signal Noise Ratio (SNR) equal 12dB, and increases the system's transmission data rate to 210.8Mb/s at BER 10−7 for 2−4−PAWM. The normalized power and bandwidth requirements will be developed. The results show, from number M=32pulses per symbol, the transmission information rate ratio (IRR) is increased to3,75. Furthermore, a study of the Peak-to-Average Power Ratio (PAPR) for various hybrid modulations is conducted. Finally, the analytical expressions for power requirements and bandwidth, PAPR, and IRR expression of the proposed modulation scheme are investigated. The results show that the proposed hybrid modulation scheme could lower the BER and increase the data rate, and demonstrates the high potential implementation for VLC technology.

A Dual Arm Complementary Hybrid Modulation Strategy Combining NL-SPWM for MMC Applications

In the medium voltage direct current (MVDC) transmission system, a small number of MMC sub modules will reduce the power quality. In this paper, based on the research background of Photovoltaic Medium Voltage Direct Current (PV-MVDC) system, a Hybrid Modulation Strategy based on the Decoupled Double Synchronous Reference Frame (DDSRF) control strategy is proposed. The dual arm complementary hybrid modulation combining nearest-level-SPWM (NL-SPWM) can keep the number of SMs in the ON state constant. Then, the corresponding voltage sharing control algorithm of sub module (SM) is introduced. Through theoretical calculation, the modulation strategy can be found to stabilize the DC voltage and reduce the harmonic content. A 32-level MMC system has been developed to verity that the proposed hybrid modulation strategy and its SM voltage sharing algorithm have the advantages of restraining circulating current and maintaining capacitor voltage balance.

ПОСТРОЕНИЕ МОЩНЫХ ШИРОКОПОЛОСНЫХ УСИЛИТЕЛЕЙ ПОСТОЯННОГО ТОКА МОДУЛЯЦИОННОГО ТРАКТА ПЕРЕДАТЧИКОВ С РАЗДЕЛЬНЫМ УСИЛЕНИЕМ СОСТАВЛЯЮЩИХ

Increasing transmission path efficiency, as the largest consumer of electricity, is relevant for any wireless communication devices, digital television, and radio broadcasting. A number of methods are used to improve efficiency, including Envelope Tracking (ET) and Envelope Elimination and Restoration (EER, or Kahn method). Increasing the bandwidth of used frequencies in 5G radio systems requires expanding the modulation path DC amplifiers bandwidth to 250…500 MHz or more. The possibility of using amplifiers with input signal quantization (AISQ) as an alternative to the most common broadband hybrid modulators combining linear and switching (with PWM) amplification channels is considered. It is shown that in order to obtain AISQ high energy characteristics, it is advisable to perform, according to the scheme with output channels parallel connection, the switching of the amplifying cells along the input circuits and to reduce the saturation voltage on the output transistors. An approach has been developed for the AISQ characteristics optimizing according to the criterion of minimum losses. The example of AISQ parameters optimization and its energy characteristics calculation for a linearly increasing signal showed that, compared with a class B amplifier (n = 1), already with three-level quantization, the loss power in the AISQ decreases by 2...2.5 times (depending on the residual transistor voltage). A further increase in n leads to a less sharp decrease in the relative loss power, which, with the obvious complication of the circuitry implementation of such AISQ, makes the use of three-four-level quantization the most expedient. With these parameters, the AISQ becomes competitive with hybrid modulators and does not create electromagnetic interference from the PWM path.

Power Scheduling Method for Grid Integration of a PV-BESS CHB Inverter With SOC Balancing Capability

The paper deals with a single-phase photovoltaic (PV) inverter based on the Cascaded H-Bridge (CHB) topology for Low Voltage (LV) grid. A distributed architecture of PV sources integrated with battery energy storage systems (BESS) is proposed with the particularity of avoiding the use of dc-dc converters. A method of compensating for the short-term daily variability of PV energy is also presented. The control implements power scheduling to ensure that constant active power is fed into the grid at every predetermined time interval (e.g., every quarter of an hour). Furthermore, a dedicated hybrid modulation scheme based on a sorting algorithm for balancing the state of charge (SOC) of the single cells is proposed. Numerical investigations are carried out on a 19-level CHB inverter implemented in a PLECS®(i.e., the simulation platform for power electronic systems from Plexim) environment to validate the feasibility and effectiveness of the proposed control strategy.

Joint Radar and Communications for Frequency-Hopped MIMO Systems

Contention in the frequency spectrum has seen the emergence of Dual-Function Radar Communications (DFRC) systems, enabling frequency-hopped (FH) multiple-input-multiple-output (MIMO) waveforms to carry communication symbols. While a variety of novel signaling strategies have been developed to facilitate the communication function, their implementation in slow-time results in the achievable data rate being limited by the radar pulse repetition interval. We develop a generalized framework for performing information embedding in DFRC systems by exploiting the fast-time structure of the transmitted radar waveform. By defining a unified formulation, we show that a variety of existing signaling strategies can be accommodated, including FH index modulation, FH permutation, quadrature amplitude modulation (QAM), M-arry PSK (MPSK) modulation and/or frequency carrier index modulation. In addition, we use this framework to propose hybrid modulation strategies constructed using combinations of the aforementioned schemes to produce significant improvements in the achievable data rate over the individual signaling schemes. Simulation results demonstrate that the hybrid schemes can deliver significantly higher bit rates with only small increases in the required <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$E_b/N_0$</tex-math></inline-formula> . They also show that, in terms of the impact on the radar operation, the frequency hopping code selection has the highest range sidelobes whereas the PSK schemes suffer from significant spectral leakage. Finally, we also give a discussion of the issues and open problems that remain unaddressed.

Design and synthesis of chromophores with enhanced electro-optic activities in both bulk and plasmonic-organic hybrid devices.

This study demonstrates enhancement of in-device electro-optic activity via a series of theory-inspired organic electro-optic (OEO) chromophores based on strong (diarylamino)phenyl electron donating moieties. These chromophores are tuned to minimize trade-offs between molecular hyperpolarizability and optical loss. Hyper-Rayleigh scattering (HRS) measurements demonstrate that these chromophores, herein described as BAH, show >2-fold improvement in β versus standard chromophores such as JRD1, and approach that of the recent BTP and BAY chromophore families. Electric field poled bulk devices of neat and binary BAH chromophores exhibited significantly enhanced EO coefficients (r33) and poling efficiencies (r33/Ep) compared with state-of-the-art chromophores such as JRD1. The neat BAH13 devices with charge blocking layers produced very large poling efficiencies of 11.6 ± 0.7 nm2 V-2 and maximum r33 value of 1100 ± 100 pm V-1 at 1310 nm on hafnium dioxide (HfO2). These results were comparable to that of our recently reported BAY1 but with much lower loss (extinction coefficient, k), and greatly exceeding that of other previously reported OEO compounds. 3 : 1 BAH-FD : BAH13 blends showed a poling efficiency of 6.7 ± 0.3 nm2 V-2 and an even greater reduction in k. 1 : 1 BAH-BB : BAH13 showed a higher poling efficiency of 8.4 ± 0.3 nm2 V-2, which is approximately a 2.5-fold enhancement in poling efficiency vs. JRD1. Neat BAH13 was evaluated in plasmonic-organic hybrid (POH) Mach-Zehnder modulators with a phase shifter length of 10 μm and slot widths of 80 and 105 nm. In-device BAH13 achieved a maximum r33 of 208 pm V-1 at 1550 nm, which is ∼1.7 times higher than JRD1 under equivalent conditions.

An integrated approach of VIKOR and teaching learning based optimization algorithm for milling machinability computations

The significance of producing Carbon nanomaterials (CNMs) reinforced polymer composites are increasing in manufacturing trades due to their exceptional performances. CNM modified composites are primarily employed in structural component needs due to expanded physicomechanical properties. This paper highlights a coherent approach of the VIšekriterijumsko KOmpromisno Rangiranje(VIKOR) and Teaching learning-based optimization algorithm (TLBO) to evaluatethe Milling efficiency. The machining was performed for the Milling process of0-D carbon nano onion (CNO) reinforced polymer (Epoxy) composite at four different levels of Box Behnken Design (BBD). The Milling performances such as Material Removal Rate (MRR) and Surface roughness (SR) were optimized to enhance product quality and productivity. The control of varying process constraints, viz. Weight % of CNO filler content(A), cutting speed (B), feed rate (C) and depth of cut (D), was used to optimize the machining response. The conflicting response is aggregated through the VIKOR method to develop the fitness function for an algorithm. The process constraints play a significant role in influencing the cost and productivity ofthe machined components. The objective function derived from VIKOR was supplied as input into the TLBO algorithm. The results demonstrated that the spindlespeed, feed rate, and weight % of CNO filler are the most contributing factors for machining indices. Also, the hybrid VIKOR-TLBO module shows a lower error percentage than the conventional VIKOR method. The microstructural investigation of the machined surface reveals the feasibility of the proposed hybrid module in a production environment.

A 100 Gbaud On-off-Keying Silicon-Polymer Hybrid Modulator Operating at up to 110°C

We demonstrate 100-Gbaud on-off-keying (OOK) transmission driven at a low voltage using an electro-optic (EO) polymer modulator combined with a silicon Mach-Zehnder interferometer waveguide. Various types of organic- and polymer-based modulators have been reported to perform efficient EO modulation and high-speed data transmission at over 100 Gbaud. However, there are critical concerns regarding the practical application of polymer devices in terms of environmental stability. In particular, long-term thermal storage and stability during operation require improvements before EO polymer modulators can be applied in practical systems. We have developed an EO polymer with enhanced thermophysical stability and used it to fabricate an efficient EO polymer modulator. In this study we extend our earlier work on high-speed EO polymer modulators by performing fiber-link 100-Gbaud OOK transmission at various operating temperatures. A thermal stability test revealed that the EO polymer modulator can survive high-temperature exposure up to 110°C. Error-free signal transmissions over a distance of 2.0 km was successfully demonstrated with a driving voltage of 1.9 V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">pp</sub> and a bit error rate below the 7% overhead forward error correction threshold. The driving voltage, bandwidth, bit error rate, and fiber-link performance of the device are presented.

Power Distribution Control Framework for Renewable Energy Architecture with Battery-Supercapacitor Based Hybrid Energy Storage Systems

Due to the intermittence and randomness of the renewable energy, hybrid energy storage system is widely adopted to suppress the power fluctuation. Power distribution is crucial for the robust and efficient operation of hybrid energy system. This paper proposes an innovative framework for hybrid energy storage system power distribution combining main circuit topology, modulation method and power distribution strategy. Firstly, hybrid modulation strategy to realize power distribution in a single-phase inverter is introduced. Then, power load prediction and low frequency filter are utilized to generate references for power distribution. Finally, the simulation model is established to test the framework and the result demonstrates the superiority of the proposed framework. The mean absolute percent error of the proposed SSA-LSTM mdoel is 0.0955 and the prediciton error by 40% compared with conventional LSTM model. Additionally, the energy management framework can adjust the port power distribution ratio flexibily to significantly suppress the power fluctuation of the grid and the operation cost of the hybrid energy storage system by reducing the charge and discharge cycle of the battery.

Sparsity-Exploiting Blind Receiver Algorithms for Unsourced Multiple Access in MIMO and Massive MIMO Channels

We propose new transmission schemes and receiver algorithms for unsourced multiple access (UMA) in MIMO and massive MIMO channels. Each active transmitter’s information bits are first channel encoded. The coded bits are divided into sub-blocks and each sub-block is modulated and transmitted. For both MIMO and massive MIMO channels, the conventional nonlinear modulation can be employed where each sub-block of coded bits is mapped to a transmitted signal vector. For the massive MIMO channel, we propose a new hybrid modulation scheme to reduce the receiver complexity, where the first sub-block is nonlinearly modulated, and the subsequent sub-blocks are linearly modulated and spread by the first sub-block signal. We also propose sparsity-exploiting blind receiver algorithms. Specifically, for the MIMO case, we exploit the codeword sparsity inherent in the UMA system, and a channel clustering technique, to estimate the channel and the transmitted signal of each transmitter. For the massive MIMO, in addition to the codeword sparsity, we further exploit the channel sparsity and user sparsity in estimating the channel and transmitted signal of each transmitter. The proposed receiver algorithms for both MIMO and massive MIMO channels output either hard or soft estimates of the coded bits, and therefore single-user channel decoding of the information bits can be performed for each transmitter. Extensive simulation results are provided to demonstrate the performances of the proposed algorithms.

Modulation and voltage balancing control of dual five-level ANPC inverter for ship electric propulsion systems

Open-end winding motors are used extensively in ship electric propulsion systems, in which medium-voltage high-power inverters are a critical component. To increase the system voltage and power density, a dual five-level active neutral-point clamped (ANPC) inverter is proposed herein to drive medium-voltage open-end winding motors for ship electric propulsion. Each phase of this inverter comprises two five-level ANPC bridges and all the phases are powered by a common direct-current link. A hybrid modulation method is proposed to control this inverter. The series-connected switches in all the five-level ANPC bridges are operated at the fundamental frequency, and the other switches are controlled with a phase-shifted pulse-width modulation (PWM), which can achieve a natural balance between the neutral-point voltage and flying capacitor voltages in a carrier period. A closed-loop capacitor voltage balancing method based on adjusting the duty ratios of the PWM signals is proposed. The neutral-point voltage and flying capacitor voltages can be controlled independently and balanced without affecting the output phase voltage. Simulation and experimental results are presented to demonstrate the validity of this method.

Multifrequency and Multiload MCR-WPT System Using Hybrid Modulation Waves SPWM Control Method

To satisfy independent and controllable power supply requirements for loads with different frequencies and power levels, a multifrequency and multiload (MFML) magnetic coupling resonant wireless power transfer (MCR-WPT) system using hybrid modulation waves sinusoidal pulsewidth modulation (HMW-SPWM) control method is proposed in this article. Based on SPWM, loading a hybrid modulation wave formed by superimposing multifrequency modulation waves to drive the inverter, so the multifrequency hybrid current on the primary side can be obtained. According to the principle of mutual inductance coupling, inductive power with different frequencies is obtained and then separated by multiresonant networks on the secondary side for loads with different frequencies. First, the structure and working principle of a MFML MCR-WPT system controlled by HMW-SPWM are introduced. Then, taking a dual-frequency and dual-load MCR-WPT system as an example, the system is mathematically modeled. Besides, parameters design criteria for reducing interfrequency interference is studied. After that, load characteristics and power factor are analyzed to select appropriate parameters. Furthermore, dynamic characteristics are analyzed. Finally, theoretical results are validated by experiments. The experimental results show that the MFML MCR-WPT system controlled by HMW-SPWM realizes independent and controllable wireless power supply for loads with different frequencies and power levels.

Tuning the Optical Properties of Au Nanoclusters by Designed Proteins

AbstractGold nanoclusters (AuNCs) are nanomaterials with interesting photoluminescent properties that can be endowed with biomolecular recognition and biocompatibility when stabilized with proteins. The interplay between the optical features of AuNCs and the function added by the protein makes them perfect candidates for generating hybrid protein‐inorganic nanomaterials. Focusing on protein stabilized‐AuNCs, hitherto most of the work has covered the use of natural proteins for in situ growth of AuNCs. However, the exploitation of design proteins for such endeavors enables fine‐tuning of the photoluminescent assets of AuNCs. In this work, rational protein engineering of modular protein scaffolds is applied for capping of non‐emissive, non‐passivated naked AuNCs, resulting in a fast and easy method for the synthesis of customizable and emissive protein‐AuNC nanomaterials. Tuning of the photoluminescent properties of the final hybrid module is obtained by appropriate choice of the coordination residues grafted on the same protein scaffold. The effects of ligands and coordination bonds are studied using time‐resolved photoluminescence and X‐ray absorbance spectroscopies, shedding light on the mechanisms behind the emerging properties of these hybrid materials. Moreover, the described versatile strategy opens new avenues for the synthesis of on‐demand photoluminescent hybrids for a wide spectrum of optical applications.

Ant Lion Optimizer (ALO) algorithm for machinability assessment during Milling of polymer composites modified by zero-dimensional carbon nano onions (0D-CNOs)

This article highlights a hybrid methodology of Grey theory and the Ant Lion Optimizer algorithm (Grey-ALO). The proposed module aggregated the multiple responses such as Cutting force (Fc) and Surface roughness (SRa) into a single objective function. The effect of varying constraints, namely, nano-filler content (CNO Wt.%), cutting speed (S), feed (F) and depth of Cut (D), is examined using Taguchi experimental design. The optimal condition from the Grey-ALO hybrid module are found as W3-S3-F1-D1, i.e., 1.5 wt.% CNO, Spindle Speed at 1500 rpm, Feed at 50 mm/min, and 1 mm of cutting depth. The validation test reveals that the overall assessment values significantly improved from 0.9136 to 0.9156, which indicates the improved prediction performance of ALO with 0.2189% error. The finding confirms that the feed rate and weight% of CNOs are the highly influencing factor for Milling performances. It can be recommended to the manufacturing sector for quality and production control.

Performance Enhancement of DWDM-FSO Optical Fiber Communication Systems Based on Hybrid Modulation Techniques under Atmospheric Turbulence Channel

In this paper, we enhance the performance efficiency of the free-space optical (FSO) communication link using the hybrid on-off keying (OOK) modulation, M-ary digital pulse position modulation (M-ary DPPM), and M-pulse amplitude and position modulation (M-PAPM). This work analyzes and enhances the bit error rate (BER) performance of the moment generating function, modified Chernoff bound, and Gaussian approximation techniques. In the existence of both an amplified spontaneous emission (ASE) noise, atmospheric turbulence (AT) channels, and interchannel crosstalk (ICC), we propose a system model of the passive optical network (PON) wavelength division multiplexing (WDM) technique for a dense WDM (DWDM) based on the hybrid fiber FSO (HFFSO) link. We use eight wavelength channels that have been transmitted at a data rate of 2.5 Gbps over a turbulent HFFSO-DWDM system and PON-FSO optical fiber start from 1550 nm channel spacing in the C-band of 100 GHz. The results demonstrate (2.5 Gbps × 8 channels) 20 Gbit/s-4000 m transmission with favorable performance. In this design, M-ary DPPM-M-PAPM modulation is used to provide extra information bits to increase performance. We also propose to incorporate adaptive optics to mitigate the AT effect and improve the modulation efficiency. We investigate the impact of the turbulence effect on the proposed system performance based on OOK-M-ary PAPM-DPPM modulation as a function of M-ary DPPM-PAPM and other atmospheric parameters. The proposed M-ary hybrid DPPM-M-PAPM solution increases the receiver sensitivity compared to OOK, improves the reliability and achieves a lower power penalty of 0.2–3.0 dB at low coding level (M) 2 in the WDM-FSO systems for the weak turbulence. The OOK/M-ary hybrid DPPM-M-PAPM provides an optical signal-to-noise ratio of about 4–8 dB of the DWDM-HFFSO link for the strong turbulence at a target BER of 10−12. The numerical results indicate that the proposed design can be enhanced with the hybrid OOK/M-DPPM and M-PAPM for DWDM-HFFSO systems. The calculation results show that PAPM-DPPM has increased about 10–11 dB at BER of 10−12 more than the OOK-NRZ approach. The simulation results show that the proposed hybrid optical modulation technique can be used in the DWDM-FSO hybrid links for optical-wireless and fiber-optic communication systems, significantly increasing their efficiency. Finally, the use of the hybrid OOK/M-ary DPPM-M-PAPM modulation schemes is a new technique to reduce the AT, ICC, ASE noise for the DWDM-FSO optical fiber communication systems.

A new ABER approximation of FSO system using PPM–GMSK hybrid modulation scheme under weak turbulence

In this paper, free space optical communication system (FSO) employing a hybrid modulation technique called pulse position modulation–Gaussian minimum shift keying (PPM–GMSK) technique, is investigated by considering log–normal as the channel fading statistics under weak turbulence. The analytical average bit error rate (ABER) and closed form expression of the proposed hybrid modulation scheme are derived. Simulation results depict the excellent agreement of the derived closed form expression with those obtained using Gauss–Hermite approximation and with the Monte Carlo simulations.

Induction Heating in Domestic Cooking and Industrial Melting Applications: A Systematic Review on Modelling, Converter Topologies and Control Schemes

In the current scenario, power electronic device-based induction heating (IH) technologies are widely employed in domestic cooking, industrial melting and medical applications. These IH applications are designed using different converter topologies, modulation and control techniques. This review article mainly focuses on the modelling of half-bridge series resonant inverter, electrical and thermal model of IH load. This review also analyses the performance of the converter topologies based on the power conversion stages, switching frequency, power rating, power density, control range, modulation techniques, load handling capacity and efficiency. Moreover, this paper provides insight into the future of IH application, with respect to the adaptation of wide band-gap power semiconductor materials, multi-output topologies, variable-frequency control schemes with minimum losses and filters designed to improve source-side power factor. With the identified research gap in the literature, an attempt has also been made to develop a new hybrid modulation technique, to achieve a wide range of power control with high efficiency. A 100 W full-bridge inverter prototype is realised both in simulation and hardware, with various modulation schemes using a PIC16F877A microcontroller. The results are compared with existing techniques and the comparisons reveal that the proposed scheme is highly viable and effective for the rendered applications.

Predictive Modeling and Correlated Response Optimization of Polymethylmethacrylate (PMMA)-Based Bio-Nano-Composite Material Using a Hybrid Module

Polymethylmethacrylate (PMMA) is commonly known as bone cement, having good biocompatibility, mechanical qualities. It is extensively used in the biomedical sector as a synthetic bone material, orthopedic surgery and dental applications. However, some primary machining is required to achieve the tailored shape, size and finish before application in the human body. This study focuses on the machining (drilling) behavior of the developed PMMA-based Hydroxyapatite (PMMA-HA) bio-nano- composites. The machining efficiency and parametric control were estimated using a combined principal component analysis (PCA) module and evaluation based on distance from average solution (EDAS). The Hydroxyapatite (HA) weight percentage (wt.%), spindle speed (SPEED) and tool material (TOOL) viz. HSS, Carbide and TiAlN are chosen according to the Taguchi-based experimental array. The objective is to get the best possible machining responses, such as the material removal rate (MRR), mean surface roughness (Ra) and circularity error ([Formula: see text] using the PCA-EDAS hybrid module. The optimal condition is found as the HSS drilling bit, 10%[Formula: see text]wt.%, SPEED-1428[Formula: see text]rpm with an improvement of 30.53%, 21.15% and 41.9% in MRR, Ra and [Formula: see text]-ERROR, respectively. The microstructural investigation scanning electron microscope (SEM) shows the excellent morphology and quality of the drilled hole in the proposed composites. Also, an X-ray diffraction (XRD) analysis of the prepared sample was done to ensure the proper reinforcement. The flexural test shows a significant expansion in the mechanical property due to the presence of HA in PMMA

CFD Numerical Modelling of a PV–TEG Hybrid System Cooled by Air Heat Sink Coupled with a Single-Phase Inverter

This study presents full transient, three-dimensional numerical models of a PV–TEG hybrid module coupled with single-phase inverter by co-simulation. The influence of factors, such as wind speed, solar radiation intensity, or ambient temperature on the PV–TEG system, was also examined. The numerical model was implemented using Ansys software which accounted the phenomena of Thomson, Seebeck, and Joule’s heat place on the TEG system. Furthermore, its impact on total electrical efficiency was studied. The heat transfer surface of the passive heat sink and forced air circulation positively affected the total heat transfer, and therefore helped to maintain the electrical efficiency at a higher level. Simulation of the single-phase inverter with a PV–TEG system allows the determination of the power characteristics of the system in real time. The results of the study presented may provide a basis for performance optimization of a practical PV–TEG-inverter hybrid system co-design.

Improved 25-level inverter topology with reduced part count for PV grid-tie applications

&lt;span lang="EN-US"&gt;A new bidirectional multilevel inverter topology with a high number of voltage levels with a very reduced number of power components is proposed in this paper. Only TEN power switches and four asymmetric DC voltage sources are used to generate 25 voltage levels in this new topology. The proposed multilevel converter is more suitable for e-mobility and photovoltaic applications where the overall energy source can be composed of a few units/associations of several basic source modules. Several benefits are provided by this new topology: Highly sinusoidal current and voltage waveforms, low Total Harmonic Distortion, very low switching losses, and minimum cost and size of the device. For optimum control of this 25-level voltage inverter, a special Modified Hybrid Modulation technique is performed. The proposed 25-level inverter is compared to various topologies published recently in terms of cost, the number of active power switches, clamped diodes, flying capacitors, DC floating capacitors, and the number of DC voltage sources. This comparison clearly shows that the proposed topology is cost-effective, compact, and very efficient. The effectiveness and the good performance of the proposed multilevel power converter (with and without PWM control) are verified and checked by computational simulations.&lt;/span&gt;