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Fault classification is crucial in fault mitigation to maintain selectivity in tripping only the faulted phase or zone in power system networks. However, inverter-interfaced renewable energy sources' unique fault current profile poses challenges to classifiers designed for conventional systems, which are inadequate in the presence of renewable energy resources such as inverter-interfaced photovoltaic (PV) or wind turbine systems in the grid. The inverters have internal protection schemes that trip during unbalanced conditions; however, in grids with high penetration of renewable energy, the inverter must ride through the fault and let relays protect the system. Moreover, the different control strategies for inverters can make the fault current small enough to be unreliable to use as a parameter in fault classifications. This study proposes a reliable fault classification method that can accurately identify faults in power systems with high penetration of renewable energy sources. This paper discusses a machine learning (ML)-based classifier using phase current and voltage magnitude to classify faults. The performance of the proposed classifier is validated against different fault scenarios in power systems like the IEEE 9-bus system. The classifier discussed in this paper achieved a satisfactory accuracy of 99.78% with voltage measurements for test conditions within three-quarters of a cycle. The classifier can be used for any three-phase system to provide correct faulted phase information to other protection components. The same methodology is extended to identify evolving faults, achieving an accuracy of 99.6% in determining the evolving fault type. Thus, the proposed ML-based classifier provides a reliable and accurate method for fault classification in power systems with high penetration of renewable energy sources. [ABSTRACT FROM AUTHOR]

This letter presents a technique that enables very fine tunability of the frequency of ring oscillators (ROs). Multiple ROs with different numbers of tunable elements were designed and fabricated in a 65-nm CMOS technology. A tunable element consists of two inverters under different local layout effects (LLEs) and a multiplexer. LLEs impact the transient response of inverters deterministically and allow to establish a fine tunable mechanism even in the presence of large process variation. The entire RO is digital and its layout is standard-cell compatible. We demonstrate the tunability of multistage ROs with post-silicon measurements of oscillation frequencies in the range of 80–900 MHz and tuning steps of 90 kHz. [ABSTRACT FROM AUTHOR]

The increasing demand for integrating renewable energy sources necessitates inverter topologies with boosting capabilities. Using inverters with boosting capability and a low number of components to integrate renewable energy sources can reduce costs. This study describes a three‐phase multilevel inverter based on extendable switching capacitors. The use of voltage‐doubling modules permits the development of the inverter's capability. By increasing the number of doubling modules, the number of output voltage levels and boost factor are increased. Furthermore, the study introduces and implements a line voltage‐based pulse width modulation approach developed for the proposed inverter. The operation of the proposed multilevel inverter, along with the pulse width modulation scheme, common mode voltage, and power loss analysis are thoroughly discussed. Additionally, a comparative analysis is provided; highlighting the advantage of reducing the number of power switches in the proposed three‐phase inverter compared to other existing topologies. Finally, a laboratory prototype is developed, operating at a 4 kHz switching frequency and with a 120 V DC‐link voltage. The experimental results corroborate the efficiency and performance of the proposed multilevel inverter, thereby validating its practical applicability. [ABSTRACT FROM AUTHOR]

Single‐component ambipolar polymers are highly desirable for organic electrochemical transistors (OECTs) and integration into complementary logic circuits with reduced process complexity. However, they often suffer from imbalanced p‐type and n‐type characteristics and/or stability issues. Herein, a novel single‐component ambipolar polymer, namely, gIDT–BBT is reported based on indacenodithiophene (IDT) as the electron donor, benzobisthiadiazole (BBT) as the electron acceptor and oligo ethylene glycol (OEG) as the side chain. Benefitting from the extended backbone planarity and rigidity of IDT, pronounced electron‐withdrawing capability of BBT, favored ionic transport from OEG together with vertical OECT device structure, a nearly balanced ambipolar OECT performance is achieved for gIDT–BBT, revealing a high transconductance of 155.05 ± 1.58/27.28 ± 0.92 mS, a high current on/off ratio >106 and an excellent operational stability under both p‐type and n‐type operation conditions. With gIDT–BBT in hand, furthermore, vertically stacked complementary inverters are successfully fabricated to show a maximum voltage gain of 28 V V−1 (VIN = 0.9 V) and stable operation over 1000 switching cycles, and then used for efficient electrooculogram recording. This work provides a new approach for the development of ambipolar single‐component organic mixed ionic–electronic conductors and establishes a foundation for the manufacture of high‐performance ambipolar OECTs and associated complementary circuits. [ABSTRACT FROM AUTHOR]

Abstract The increasing demand for integrating renewable energy sources necessitates inverter topologies with boosting capabilities. Using inverters with boosting capability and a low number of components to integrate renewable energy sources can reduce costs. This study describes a three‐phase multilevel inverter based on extendable switching capacitors. The use of voltage‐doubling modules permits the development of the inverter's capability. By increasing the number of doubling modules, the number of output voltage levels and boost factor are increased. Furthermore, the study introduces and implements a line voltage‐based pulse width modulation approach developed for the proposed inverter. The operation of the proposed multilevel inverter, along with the pulse width modulation scheme, common mode voltage, and power loss analysis are thoroughly discussed. Additionally, a comparative analysis is provided; highlighting the advantage of reducing the number of power switches in the proposed three‐phase inverter compared to other existing topologies. Finally, a laboratory prototype is developed, operating at a 4 kHz switching frequency and with a 120 V DC‐link voltage. The experimental results corroborate the efficiency and performance of the proposed multilevel inverter, thereby validating its practical applicability.

Abstract 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.

Summary: Multilevel inverters are known as essential converters in renewable sources. First, in this paper, a new submodule is presented, and based on it, a new sub‐multilevel inverter is presented. The proposed sub‐multilevel inverter consists of several unidirectional and bidirectional switches and DC voltage sources. Then, the generalized topology, developed in two modular and cascaded modes, is presented to increase production levels. The proposed submodules are connected in series in the modular topology, increasing production levels. The proposed topology to produce the maximum output levels has the minimum number of IGBTs, drivers, DC voltage sources, etc. Mathematical analyses for conduction and switching losses are provided, and mathematical analyses for the number of devices and voltage across the switches are also presented. In addition to the mathematical analysis of losses, the simulation results are also presented. A general comparison of proposed topology components is presented to demonstrate their advantages. This comparison shows that the proposed topology has the minimum number of power electronic devices. In this paper, nearest level modulation is used to control the proposed topology. The simulation and experimental results of the proposed sub‐multilevel verify the performance of the proposed topology. [ABSTRACT FROM AUTHOR]

Photovoltaic power generation and energy storage technology are current hotspots in the clean energy industry. As a core piece of equipment, an inverter is subjected to higher demands for its voltage regulation range and output performance. A differential boost inverter features a boosting function not found in traditional inverters, effectively widening the input voltage range, with characteristics of a single-stage structure and simple modulation. However, the differential boost inverter faces the issue of high common-mode voltage. Considering that the magnitude of the common-mode voltage changes with different modulation methods, a novel modulation strategy with a flexible common-mode voltage is proposed, which can effectively suppress the common-mode voltage under the same gain without affecting the output power quality. This article first introduces the topology, working principle, and traditional modulation methods of the differential boost inverter. Then, the new modulation strategy is defined, and the gain equation is derived. The new modulation method's applicable scenarios are discussed and compared to other modulation methods based on the gain curve, concluding that the new method has advantages in terms of common-mode voltage amplitude and power quality under low boost gain. Finally, the effectiveness of the proposed method is verified through simulation and experiments. [ABSTRACT FROM AUTHOR]

A Rectangular core–shell (RCS), employed to three fins vertically stacked with gate oxide stack junctionless nanosheet, along with doping and gate/dielectric engineering, is explored. This paper proposes an N-type three fins vertically stacked with gate oxide stack junctionless nanosheet with opposite core doping in the channel referred to as RCS. The simulation results show that three fins vertically stacked with gate oxide stack with RCS junctionless nano-sheet exhibit reduced Ioff is 6.913E-21, increased Ion is 2.408E-07, Ion/Ioff ratio is 0.418×106, DIBL is 6.9mV and SS is 60.65 mV/dec, respectively. Furthermore, the P-type of three fins vertically stacked with gate oxide stack junctionless nanosheet and combined -type and P-type three fins vertically stacked with gate oxide stack junctionless nano-sheet were stimulated to construct the inverter circuit. The Voltage Transfer Characteristics (VTC) of three fins vertically stacked with gate oxide stack junctionless nano-sheet with RCS have HfO2 as the gate-oxide based inverter has been notably improved compared to SiO2, al2O3 as a gate oxide and conventional three fins vertically stacked with gate oxide stack junctionless nano-sheet inverter. [ABSTRACT FROM AUTHOR]

This paper presents a single-phase Full-Bridge (FB) inverter with a hybrid commutation technique designed to reduce the harmonic distortion caused by the loss of the controller capability around the zero-crossing point in the unipolar commutation region. The hybrid modulation changes from unipolar to bipolar commutation under the loss of the reference control, improving the robustness and efficiency of the method. The commutation technique improves the switching performance and reduces the switching losses. Simulation models are developed in MATLAB/Simulink R2023b to evaluate their performance under different operating conditions. The results show that the proposed commutation technique can achieve high efficiency, low total harmonic distortion (THD), and fast dynamic response. The experimental implementation of sliding mode control (SMC) implemented in an STM32 microcontroller confirms that the hybrid commutation technique can reduce the THD by 0.96 percentage points for local (off-grid) loads and up to 2.45 in an industrial grid-tie network, compared with unipolar commutation. These findings highlight the potential of the proposed modulation technique for applications like solar panels and offer crucial insights for ongoing research and development in this field. [ABSTRACT FROM AUTHOR]

The main contribution of this paper is to present a simple algorithm that theoretically and numerically assesses the switching angles of an inverter operated with the SPWM technique. This technique is the most widely used for eliminating harmonics in DC-AC converters for powering motors, renewable energy applications, household appliances, etc. Unlike conventional implementations of the SPWM technique based on the analog or digital comparison of a sinusoidal signal with a triangular signal, this paper mathematically performs this comparison. It proposes a simple solution to solve the transcendental equations arising from the mathematical analysis numerically. The technique is validated by calculating the total harmonic distortion (THD) of the generated signal theoretically and numerically, and the results indicate that the calculated angles produce the same distribution of harmonics calculated analytically and numerically. The algorithm is limited to single-phase inverters with unipolar SPWM. [ABSTRACT FROM AUTHOR]

For applications involving the implantation of organic thin‐film transistors (OTFTs) in flexible environments, maintaining uniform device performance and ultrathin profiles with excellent mechanical stability is crucial for dynamic deformable conditions. This study presents high‐performance, mechanically flexible ultrathin OTFTs with a thickness under 5 µm, designed to be scalable for utilization in large areas. The OTFTs utilized an organosilicon polymer dielectric layer synthesized via initiated chemical vapor deposition combined with the crystalline organic semiconductor 2‐Decyl‐7‐phenyl[1]benzothieno[3,2‐b][1]benzothiophene (Ph‐BTBT‐10). Compared with conventional organic transistors, the OTFTs exhibited exceptional features, such as a charge carrier mobility of up to 7 cm2 V−1 s−1 and a near‐zero threshold voltage. Their performance is showcased across 900 devices on a 10 cm × 10 cm substrate to ensure uniformity and scalability. Additionally, the OTFTs demonstrate remarkable resilience to mechanical deformation, with a 97.4% mobility retention rate under a 20% tensile compression. After 1000 cycles of repeated deformation stress, they maintain a robust 94.6% performance level compared with the initial state. In summary, the ultrathin flexible OTFTs exhibit exceptional resilience to mechanical deformation, extended air exposure, uniformity in large arrays, and high mobility. This makes them promising for diverse applications, such as in vivo organ monitoring and skin displays. [ABSTRACT FROM AUTHOR]

With the rapid development of global energy transformation and new power system, ensuring the stability of distributed energy grid connections is the key to maintaining the reliable operation of the whole power system. This paper constructs detailed impedance models of grid-following (GFL) and grid-forming (GFM) inverters using a harmonic linearization method and thoroughly investigates the mechanisms of resonance when inverters are connected to the grid, as well as the impact of model parameters on the stability of the grid system. This paper also briefly analyzes the scenario where distributed energy and electric vehicles are integrated into the grid simultaneously, demonstrating that grid system stability can be ensured in complex grid situations through reasonable parameter design. Lastly, the accuracy of the proposed impedance models and analysis is verified through MATLAB/Simulink simulations. [ABSTRACT FROM AUTHOR]

Abstract Single‐component ambipolar polymers are highly desirable for organic electrochemical transistors (OECTs) and integration into complementary logic circuits with reduced process complexity. However, they often suffer from imbalanced p‐type and n‐type characteristics and/or stability issues. Herein, a novel single‐component ambipolar polymer, namely, gIDT–BBT is reported based on indacenodithiophene (IDT) as the electron donor, benzobisthiadiazole (BBT) as the electron acceptor and oligo ethylene glycol (OEG) as the side chain. Benefitting from the extended backbone planarity and rigidity of IDT, pronounced electron‐withdrawing capability of BBT, favored ionic transport from OEG together with vertical OECT device structure, a nearly balanced ambipolar OECT performance is achieved for gIDT–BBT, revealing a high transconductance of 155.05 ± 1.58/27.28 ± 0.92 mS, a high current on/off ratio >106 and an excellent operational stability under both p‐type and n‐type operation conditions. With gIDT–BBT in hand, furthermore, vertically stacked complementary inverters are successfully fabricated to show a maximum voltage gain of 28 V V−1 (VIN = 0.9 V) and stable operation over 1000 switching cycles, and then used for efficient electrooculogram recording. This work provides a new approach for the development of ambipolar single‐component organic mixed ionic–electronic conductors and establishes a foundation for the manufacture of high‐performance ambipolar OECTs and associated complementary circuits.

Purpose – Traditional level inverter technology has drawbacks in the aspect of Total harmonic distortion (THD) and switching losses for higher frequencies. Due to these drawbacks, two-level inverters have become unprofitable for high-power applications. Multilevel inverters (MLIs) are used to enhance the output waveform characteristics (i.e. low THD) and to offer various inverter topologies and switching methods. Design/methodology/approach – MLIs are upgraded versions of two-level inverters that offer more output levels in current and voltage waveforms while lowering the dv/dt and di/dt ratios. This paper aims to review and compare the different topologies of MLI used in high-power applications. Single and multisource MLI's working principal and switching states for each topology are demonstrated and compared. A Simulink model system integrated using detailed circuit simulations in developed in MATLAB®–Simulink program. In this system, a constant voltage source connected to MLI to feed asynchronous motor with squirrel cage rotor type is used to demonstrate the efficacy of the MLI under different varying speed and torque conditions. Findings – MLI has presented better control and good range of system parameters than two-level inverter. It is suggested that the MLIs like cascade-five-level and NPC-five-level have shown low current harmonics of around 0.43% and 1.87%, respectively, compared to two-level inverter showing 5.82%. Originality/value – This study is the first of its kind comparing the different topologies of single and multisource MLIs. This study suggests that the MLIs are more suitable for high-power applications.

Abstract As the penetration of distributed generation (DG) systems in the grid is increasing, the challenge of combining large numbers of DGs in the power systems has to be carefully clarified and managed. The control strategy and management concept of the interconnected systems should be flexible and reliable to handle the various types of DGs. This can be suitably met by microgrids. This paper introduces the microgrid structure and elements and states the main objectives that should be achieved by the microgrid controllers and each DG controller in both operation modes (grid‐connected and island mode). It also presents the challenges of having multiple DG units in a microgrid in terms of accurate power control/sharing, voltage and frequency regulation, power management between DGs, different renewable energy sources integration and deployment, seamless mode transfer, and the modeling issues. The centralized and decentralized control techniques as potential solutions have been discussed and compared by highlighting the advantages and disadvantages of each. Furthermore, the recent control techniques for drooped alternating current microgrids and the main proposed solutions and contributions in the literature have been exposed to finally overcome the droop control limitations and obtain a flexible and smart distributed power system.

Volt-VAR and Volt-Watt functionality in photovoltaic (PV) smart inverters provide mechanisms to ensure system voltage magnitudes and power factors remain within acceptable limits. However, these control functions can become unstable, introducing oscillations in system voltages when not appropriately configured or maliciously altered during a cyberattack. In the event that Volt-VAR and Volt-Watt control functions in a portion of PV smart inverters in a distribution grid are unstable, the proposed adaptation scheme utilizes the remaining and stably-behaving PV smart inverters and other Distributed Energy Resources to mitigate the effect of the instability. The adaptation mechanism is entirely decentralized, model-free, communication-free, and requires virtually no external configuration. We provide a derivation of the adaptive control approach and validate the algorithm in experiments on the IEEE 37 and 8500 node test feeders.

This paper presents the experimental results of nMOS quantum dot gate field-effect transistor (QDG-FET) based four-state inverter fabricated and tested with Si/SiO2 and Ge/GeO2 quantum dots. The site-specific self-assembly of SiOx-cladded Si and GeOx-cladded Ge quantum dot layers in the gate region implements both the driver and load FETs in enhancement nMOS inverters. A four-state inverter will allow the reduction of FET count in logic block in microprocessors. [ABSTRACT FROM AUTHOR]

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In literature, to generate gate pulses for any inverter topology, most of the authors are using a single modulating signal with (level-1) or (level-1)/2 carrier-based pulse width modulation (PWM) techniques and single carrier (SC) signal with (level-1)/2 modulating signal based PWM techniques. Then, while going to higher-level inverter topologies, the complexity of the PWM control approach in both cases can increase. To reduce the control complexity, few authors have reported a single modulating signal with single carrier-based PWM techniques. However, these techniques need more mathematical equations and if-else loops. This article proposes a new single-modulating and single-carrier signal-based generalized PWM control approach using floor function (FF). This technique has been verified by considering one of the single-phase conventional symmetrical and asymmetrical multilevel inverter (MLI) topologies. Generally, FF rounds the value to the nearest integer towards the negative infinity. The proposed PWM control implementation process is very simple and suitable for both high switching frequency (HSF) and low switching frequency (LSF) operations. The proposed control technique (PCT) has been experimentally verified with different steady-state and transient-state studies of results under standalone operation. [ABSTRACT FROM AUTHOR]

Voltage-source inverter is a significant part of power supply for various applications. In hard working conditions, the inverter is prone to failure, such as open-circuit (OC) faults, which bring great risk to the safe operation. Therefore, a simple and robust fault diagnosis method for OC faults of voltage-source inverter is proposed. First, the fault principle of OC fault is studied, and a rule of voltage sequence is found that the sequence of positive and negative abnormal voltages is related to the fault position. Then, available line voltages are used as fault diagnosis variables, the fault phase is detected by abnormal values of line voltages, and the fault switch is located according to the fault phase and the rule of voltage sequence. Different from existing OC fault diagnosis methods, the proposed method is immune to phase to phase short-circuit fault, which has not been referred to or discussed in existing literatures yet but can lead to the false diagnosis of OC fault diagnosis methods. Moreover, the proposed method is robust to load variation, switching and fundamental frequencies. The experimental tests are carried out on a dSPACE platform, and the proposed method is verified. [ABSTRACT FROM AUTHOR]

As the penetration of distributed generation (DG) systems in the grid is increasing, the challenge of combining large numbers of DGs in the power systems has to be carefully clarified and managed. The control strategy and management concept of the interconnected systems should be flexible and reliable to handle the various types of DGs. This can be suitably met by microgrids. This paper introduces the microgrid structure and elements and states the main objectives that should be achieved by the microgrid controllers and each DG controller in both operation modes (grid‐connected and island mode). It also presents the challenges of having multiple DG units in a microgrid in terms of accurate power control/sharing, voltage and frequency regulation, power management between DGs, different renewable energy sources integration and deployment, seamless mode transfer, and the modeling issues. The centralized and decentralized control techniques as potential solutions have been discussed and compared by highlighting the advantages and disadvantages of each. Furthermore, the recent control techniques for drooped alternating current microgrids and the main proposed solutions and contributions in the literature have been exposed to finally overcome the droop control limitations and obtain a flexible and smart distributed power system. [ABSTRACT FROM AUTHOR]

Copyright of Gazi Üniversitesi Fen Bilimleri Dergisi Part C: Tasarım ve Teknoloji is the property of Gazi University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Nowadays, the high penetration of inverter-interfaced distributed energy resources (DERs) has raised a well-founded concern regarding the interaction of these devices with the upstream grid. The harmonic interaction phenomenon between these players can be described by time-domain simulations, using high computational effort switched and/or average models often impractical for large power systems. This paper proposes an innovative low-computational-burden model named passive impedance network (PIN), capable of accurately representing DERs in electric power systems (EPSs). Through passive RLC components, the PIN model can describe DER dynamic behavior at a certain frequency of interest, making it able to represent harmonic flow within the EPS nodes. The proposed model is compared with the switched model, average model, and an experimental setup under different grid distortions and injected current profiles. A comparison of the total demand distortion (TDD) between the proposed PIN model and the experimental results is carried out. The effect of DER parameter deviations on PIN model accuracy is addressed, in which the absolute error of the PIN model TDD values are 0.65% and 0.06% for the experimental and switched model, respectively. Besides, the PIN model presents an improved computational performance compared to the time-domain-based switching model, requiring 99% less computational burden.

Abstract For applications involving the implantation of organic thin‐film transistors (OTFTs) in flexible environments, maintaining uniform device performance and ultrathin profiles with excellent mechanical stability is crucial for dynamic deformable conditions. This study presents high‐performance, mechanically flexible ultrathin OTFTs with a thickness under 5 µm, designed to be scalable for utilization in large areas. The OTFTs utilized an organosilicon polymer dielectric layer synthesized via initiated chemical vapor deposition combined with the crystalline organic semiconductor 2‐Decyl‐7‐phenyl[1]benzothieno[3,2‐b][1]benzothiophene (Ph‐BTBT‐10). Compared with conventional organic transistors, the OTFTs exhibited exceptional features, such as a charge carrier mobility of up to 7 cm2 V−1 s−1 and a near‐zero threshold voltage. Their performance is showcased across 900 devices on a 10 cm × 10 cm substrate to ensure uniformity and scalability. Additionally, the OTFTs demonstrate remarkable resilience to mechanical deformation, with a 97.4% mobility retention rate under a 20% tensile compression. After 1000 cycles of repeated deformation stress, they maintain a robust 94.6% performance level compared with the initial state. In summary, the ultrathin flexible OTFTs exhibit exceptional resilience to mechanical deformation, extended air exposure, uniformity in large arrays, and high mobility. This makes them promising for diverse applications, such as in vivo organ monitoring and skin displays.

A Rectangular core-shell (RCS) is analyzed on vertically stacked gate oxide junctionless nanosheet along with doping and gate/dielectric engineering. This paper also proposes an N-type three fins vertically stacked with gate oxide stack junctionless nanosheet with opposite core doping in the channel known as RCS. The simulation results show that gate oxide stack with RCS junctionless nanosheet exhibit reduced $I_{\mathrm {OFF}}$ is 6.913E-21, increased $I_{\mathrm {ON}}$ is 2.408E-07, $I_{\mathrm {ON}}$ / $I_{\mathrm {OFF}}$ ratio is $0.418\times 10^{6}$ , DIBL is 6.9mV and SS of 60.65 mV/dec respectively. The core shell width variations with various gate oxide dielectric towards better $I_{\mathrm {ON}}$ , $I_{\mathrm {OFF}}$ and $I_{\mathrm {ON}}$ / $I_{\mathrm {OFF}}$ are analyzed. Interestingly, it is noted that for smaller shell thickness, the thickness of core should be equivalent to shell thickness and for larger shell thickness, thicker core is required. The device robustness towards analog and RF metrics are also evaluated with varied gate dielectrics. It has been observed that RCS architecture with opposite doping with HfO2 as gate oxide material has given outstanding outcomes compared to other gate oxide materials and without RCS method. Further, simulated the P-type of three fins vertically stacked with gate oxide stack junctionless nanosheet and combined both N-type and P-type three fins vertically stacked with gate oxide stack junctionless nanosheet to construct the CMOS inverter circuit. The voltage transfer characteristics (VTC) characteristics of junctionless nanosheet with RCS having HfO2 as gate-oxide based inverter has been notably improved as compared to the SiO2, Al2O3 and conventional three fins vertically stacked with gate oxide stack junctionless nanosheet inverter.

This paper describes the effects of power device characteristics on the harmonics of the inverter output voltage and magnetic field leakage in a wireless power transfer system for electric vehicles with phase shift control and the suppression method of the haemonics. Even when the phase shift angle is theoretically set to minimize harmonics, the experimental results have confirmed the existence of the remaining harmonics, which have dead-time dependence. Harmonics with dead-time dependence include those caused by changes in the pulse width depending on the dead time, which have been conventionally compensated for by dead-time compensation. However, the targeted harmonics have a dead-time dependence even when the pulse widths are matched. Therefore, we focused on the difference between the dead-time period and other periods. Further, as the conduction resistance differs between these two periods, we performed a circuit analysis, also considering the conduction resistance. From the results, it was theoretically clarified that harmonics are generated because of the difference in resistance in the forward and reverse directions of power devices. Furthermore, the theoretically calculated dead time dependence of the device-induced harmonics was confirmed by experimental measurements of the harmonics of the inverter output voltage waveform and the magnetic field leakage. This confirms that one of the factors responsible for the harmonics is the difference in the device conduction resistance before and after the dead-time period. The main contributions of this paper are the revelation of unconventional dead-time-dependent harmonics and the proposal of a method for suppressing them.

A novel control scheme applicable to in-road inductive wireless charging pads in a dynamic system is presented. Primary inverter current sensing allows the primary pad to detect an approaching secondary pad. Zero-crossing detection of the same current allows the primary to synchronize to the secondary, functioning as a synchronous inverter with dual-active switching. Such primary synchronous inverters allow for independent primary pads. Necessary measures to ensure stable operation of the design are discussed. The control scheme only adds an analog filter to the bare-bones open-loop design. The design is validated through simulation and hardware experimentation, with a strong demonstration of robustness.

Modern electric railway vehicles are faced with the challenge of achieving electromagnetic compatibility (EMC) compliance with railway signaling systems. Currently, no established countermeasures or design methods that guarantee passing the EMC compliance test are available. Therefore, the enhancement of EMC management during vehicle manufacturing processes is imperative. This study devised a pre-accreditation method to be implemented at the vehicle completion stage, prior to the EMC compliance test. The proposed method entails the substitution of real ground signaling devices, whose parameters are difficult to obtain, with unified coils. The effectiveness of this approach is validated by observing whether the gain difference remains consistent when using both an exciting coil and a test train. To illustrate this method, we selected the platform screen door (PSD) balise as a representative signaling device, which is widely utilized in various railway stations. The unified coil employed in this study can be easily fabricated. First, we measured the gain difference (the ratio between the induced voltage of coils and the exciting coil current) between the PSD balise and unified coil. Next, we measured the unknown magnetic flux induced by an 8-car electric multiple unit test train by utilizing the PSD balise and unified coil. Finally, we calculated the measured difference between them. The gain and measured differences properly agreed (within 6 dB) across a wide frequency range of 200 kHz to 4 MHz.

This study presents a novel, integrated approach to investigating and characterizing the impact of humidity on Insulated-Gate Bipolar Transistors (IGBTs) within large-scale inverter systems. Combining meticulously designed experimental setups and advanced finite element simulations, we delve deep into the complex dynamics of moisture transfer within IGBT modules. Our research demonstrates a meticulously designed experimental setup within a controlled climate chamber, enabling a comprehensive characterization process of the humidity transfer into the IGBT module. The proposed method allows for a detailed study of the moisture distribution as well as the effect of the temperature on the moisture within an IGBT module. We leverage the advanced capabilities of commercial finite element software to complement our experimental findings. These simulations enable a deeper understanding of the moisture distribution's symmetries and provide invaluable insights into simplifying the complex simulations. By integrating these diverse methodologies, we develop a comprehensive approach that deciphers the spatial distribution of humidity within the module and its real-time responses to environmental conditions. This integrated approach holds an immense potential for analyzing optimal system performance and facilitating self-optimization of the inverter by predicting stress induced by humidity.

An inexact 6-transistor full adder (FA) cell is presented. It is low-power and gives full-swing outputs because of the applied gate diffusion input (GDI) along with the dynamic threshold (DT) techniques. The FA which has three errors is used in a 10-transistor inexact 4:2 compressor based on the stacking circuit idea. The implementation by a 16-nm carbon nanotube field-effect transistor (CNTFET) technology shows a small area of 0.027 and $0.045~\mu \text{m}^{\mathrm{ 2}}$ for the FA and compressor, respectively. A new approximate sum of absolute differences (SADs) block is presented by the FA and compressor. The average power, power-delay-product (PDP), and peak signal-to-noise ratio (PSNR) of the SAD are 6.80 mW, 33.86 nJ, and 42.98 dB, respectively, which confirm its efficiency for bioimages difference detection. [ABSTRACT FROM AUTHOR]

The application of electrochemical cells as a source unit of electrical energy is rapidly growing—used in electric vehicles and other electric mobility devices, as well as in energy supply systems—as energy storage, often together with renewable energy sources. The key element of such systems is the power electronic converter used for DC energy storage and AC grid interfacing. It should be bidirectional to charge and discharge the battery when it is necessary. Two-stage battery interface converters are the most common; their DC-DC stage controls the battery current and adjusts voltage, but the DC-AC stage (inverter or frontend) controls the current in the grid. The use of unfolding inverters in two-stage battery interfaces can have some advantages. In this case, the DC-DC converter produces half-sinewave pulsating voltages and currents, but the unfolding circuit changes the polarity of the voltages and currents and produces no switching losses. Another trend of modern power electronics is the principle of partial power processing. In this case, power electronic converters deal only with a part of the total power; therefore, losses in such converters are reduced. This paper considers combining unfolding frontends with partial power DC-DC converters that enable the further reduction in losses. In this paper, it is shown that such implementation of the partial power conversion principle in semi-DC-AC systems is really possible based on the real-time matching of the voltage of the partial-power DC-DC converter, battery voltage (which depends on its state of charge) and the rectified instantaneous voltage of the AC grid. [ABSTRACT FROM AUTHOR]

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A quadratic converter is now a days being investigated for high boost topologies. This paper presents the quadratic converter-based single-phase grid-connected system. For this system, the DC side control loop is regulated using a symmetrical shoot-through (SST)-based PWM. AC side current controller is implemented by the variation of modulation index in a nearly decoupled manner. The advantage of the suggested system is in terms of several controls particularly for input variations and load changes which are most beneficial in the case of grid application. The experimental results are presented to support the simulation results. The simulation results are achieved using MATLAB/SIMULINK. [ABSTRACT FROM AUTHOR]

1ϕ Z/quasi-Z source (ZSI/qZSI) inverters are nowadays increasingly used in a variety of power applications like renewable energy. During the rectification process of AC to DC side, the low-frequency ripples (2ω) are present in the DC side inductor current, capacitor voltage and also in DC-link voltage. These low-frequency ripples are the double line frequency power ripples that occur at two times the fundamental frequency i.e. at 100 Hz. In the case of renewable energy applications such as PV and fuel cells, these ripples are most hazardous. Due to current and voltage (2ω) ripples, the extraction of power from PV/fuel cell reduces. It also decreases its lifetime. These low-frequency ripples also increase the output current and voltage distortion. Ultimately it affects the performance of a system and degrades its power quality. Passive power decoupling techniques are used to eliminate/reduce low-frequency power ripples (2ω). The primary contribution of this article is to show a comprehensive overview of the passive power decoupling technique for the second harmonic (2ω) power elimination over two decades. This article also provides a proposed modified control strategy that achieves the elimination/reduction of (2ω) ripple in inductor current and capacitor voltage at the lowest values of qZS inductor and capacitor. The simulation and experimental results are also obtained for the proposed model. [ABSTRACT FROM AUTHOR]

Voltage source inverters are currently gaining popularity in a variety of power system applications, including renewable energy, HVdc, and microgrid. Among all the renewable energy applications, multilevel inverters (MLIs) are the most popular converters for high- and medium-power industries. This article reviews and compares many of the recently developed topologies for renewable energy integration with energy storage systems (ESSs). In addition, a new design of a seven-level inverter is proposed. It utilizes only six power electronic switches in its design of which four have unidirectional voltage-blocking capability and two have bidirectional voltage-blocking capability. Various simulation results of the proposed topology along with the total harmonic distortion (THD) contents of voltage and current are presented in detail under different loading conditions. Afterward, a new factor of comparison is proposed in which component ratings are also considered. Finally, a hardware prototype is built to check the authenticity of the proposed design, and satisfactory results are presented. [ABSTRACT FROM AUTHOR]

This paper conducts a comprehensive analysis of offshore wind-photovoltaic hybrid systems, presenting autonomous components tailored for maritime applications. Focusing on the critical role of these systems in supplying electricity to regions with limited infrastructure, particularly maritime zones, the study explores economic advantages over traditional power line installations, emphasizing remote areas. Key components, including battery storage, autonomy, battery selection (with a spotlight on lead-acid batteries), charge controllers, inverters, and the integration of Automatic Identification System (A.I.S.) for maritime safety, are discussed. The article concludes by underscoring the significance of power supply buoys for ship safety and efficient refueling near hybrid systems. [ABSTRACT FROM AUTHOR]

This paper Techno-economic design of a standalone solar PV system with case study, TY Danjuma conference building, Rivers State University (RSU) Port-Harcourt provides alternative electric power services to the building. The area or building under consideration uses the off-grid power generation model having identified the inadequacy and irregular power supply which causes man-hour loss during the working period. There is enough solar energy to generate emission-free power. In literature, it has been seen that researchers are advocating for the utilization of these abundant natural resources to generate power. The long-run operational benefits cannot be neglected. To achieve the aim and objectives of this research, an analytical (components-wise) method was adopted. The various components required to provide green energy services were thoroughly and chronologically computed. The analysis provides specifications for the components as mentioned in the materials section and concerning the load demanded. Without a thorough load audit, the required solar PV and its delivery gadgetry would not be adequate. Hence, load survey, assumption and design calculations, etc., to achieve the 42kWp with 140 numbers of panels; 48 numbers of 200Ah, 12V deep cycle batteries, 25kVA inverter (or with two sets of inverters, 15kVA and 10kVA, 48Vdc/220Vac), 6 numbers of 150Amp, 48V solar charge controllers or a single 900Amp,48V solar charge controller was evaluated. The specification evaluated and presented was based on the load computed and the prevailing market for available components. From the techno-economic viewpoint of using solar-powered systems or diesel-powered generators, it was obvious that the solar-powered system has many more advantages in terms of daily, monthly or yearly running and maintenance costs as comparable to diesel-generator systems. Thus, it will be interesting to note that adequate utilization of renewable energy for electricity generation will be the best practice in the socioeconomic development of a state or a nation.

Photovoltaic power generation and energy storage technology are current hotspots in the clean energy industry. As a core piece of equipment, an inverter is subjected to higher demands for its voltage regulation range and output performance. A differential boost inverter features a boosting function not found in traditional inverters, effectively widening the input voltage range, with characteristics of a single-stage structure and simple modulation. However, the differential boost inverter faces the issue of high common-mode voltage. Considering that the magnitude of the common-mode voltage changes with different modulation methods, a novel modulation strategy with a flexible common-mode voltage is proposed, which can effectively suppress the common-mode voltage under the same gain without affecting the output power quality. This article first introduces the topology, working principle, and traditional modulation methods of the differential boost inverter. Then, the new modulation strategy is defined, and the gain equation is derived. The new modulation method’s applicable scenarios are discussed and compared to other modulation methods based on the gain curve, concluding that the new method has advantages in terms of common-mode voltage amplitude and power quality under low boost gain. Finally, the effectiveness of the proposed method is verified through simulation and experiments.

This paper presents a single-phase Full-Bridge (FB) inverter with a hybrid commutation technique designed to reduce the harmonic distortion caused by the loss of the controller capability around the zero-crossing point in the unipolar commutation region. The hybrid modulation changes from unipolar to bipolar commutation under the loss of the reference control, improving the robustness and efficiency of the method. The commutation technique improves the switching performance and reduces the switching losses. Simulation models are developed in MATLAB/Simulink R2023b to evaluate their performance under different operating conditions. The results show that the proposed commutation technique can achieve high efficiency, low total harmonic distortion (THD), and fast dynamic response. The experimental implementation of sliding mode control (SMC) implemented in an STM32 microcontroller confirms that the hybrid commutation technique can reduce the THD by 0.96 percentage points for local (off-grid) loads and up to 2.45 in an industrial grid-tie network, compared with unipolar commutation. These findings highlight the potential of the proposed modulation technique for applications like solar panels and offer crucial insights for ongoing research and development in this field.

The main contribution of this paper is to present a simple algorithm that theoretically and numerically assesses the switching angles of an inverter operated with the SPWM technique. This technique is the most widely used for eliminating harmonics in DC-AC converters for powering motors, renewable energy applications, household appliances, etc. Unlike conventional implementations of the SPWM technique based on the analog or digital comparison of a sinusoidal signal with a triangular signal, this paper mathematically performs this comparison. It proposes a simple solution to solve the transcendental equations arising from the mathematical analysis numerically. The technique is validated by calculating the total harmonic distortion (THD) of the generated signal theoretically and numerically, and the results indicate that the calculated angles produce the same distribution of harmonics calculated analytically and numerically. The algorithm is limited to single-phase inverters with unipolar SPWM.