High-performance Converters Research Articles

Efficient Integration of PV Panels and Electrolysis through a High-Performance Converter for Clean Hydrogen Generation

Green power generation revolves around producing clean hydrogen. This is achieved through a process of generating hydrogen by electrolysis, which draws power from renewable energy sources. In this manuscript, a high performance step-down isolated dc-dc converter is proposed to interface the Photovoltaic (PV) panels and the electrolysis. This converter is highly efficient and capable of toggling on and off with minimal power consumption. The primary function of the electrolyser is to generate hydrogen, and the quantity of hydrogen produced correlates with the amount of electricity (current) it receives. To ensure seamless operation, a control system is employed. This system monitors the current and voltage of the electrolyser, ensuring it remains within optimal levels. To assess the efficacy of the proposed configuration, the system is simulated in MATLAB platform and a complete hardware in the loop test is performed using OPAL-RT OP4510.

Adaptive TS-ANFIS neuro-fuzzy controller based single phase shunt active power filter to mitigate sensitive power quality issues in IoT devices

The emergence of Internet of Things (IoT) offers numerous functions, such as intelligent sensor integration, remote sensing, and high-speed data transmission, which have found widespread applications in the smart industry and commercial applications. The associative nonlinear effects of a variety of undesirable power quality concerns were resolved by using harmonic mitigation in nonlinear loads and high-performance converters were built on power electronics in conventional systems. Among other performance objectives, total harmonic (THD) distortion analysis and higher order harmonics mitigation is given main concern in smart electronics equipment. This paper proposes an approach to minimize higher-order harmonics due to nonlinear load disturbances in smart IoT devices using the Takagi–Sugeno (TS) Neuro Fuzzy (TS-ANFIS) supervised shunt APF. The proposed work elicits the novel adaptive harmonic mitigation technique in hybrid IoT embedded systems to protect from malfunctioning and to deal with the uncertainty of harmonic signal stimuli in sensitive sensors-based IoT systems. Hysteresis current control is used for the ignition of reference signal under uncertainty of harmonic stimuli. The single phase shunt APF is used to mitigate higher-order harmonics from supply mains, while the implementation of TS-ANFIS supervises the controller action to generate a trigger signal for adequate single phase APF gate excitation. The higher order harmonic current data set is used for error deviation for training neural networks and adaptive control. The estimated adoption of the neuron's empirical weight reduces the total THD to a significant reduction rate of 72.8 % to 0.78 %. The control mechanism is feasible for a range of smart IoT systems to adhere to the standard of 519 (IEEE).

High-Performance Thermionic Energy Converters Based on Cd3As2 Anode

The unusual electronic properties of 3-D topological Dirac semimetals have led to intensive research efforts focusing on their potential applications in high-performance electronic, photonic, and optoelectronic devices. In this work, we propose a conceptual design of thermionic energy converters (TECs) based on a Cd <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> As <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> anode with significantly improved performance. Using the electronic properties of Cd <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> As <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> —an air-stable topological Dirac semimetal—from first-principle density functional theory (DFT) calculation, such a device can achieve a maximum output power density and conversion efficiency of 10.96 W/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> and 57.29% at 1800 K, respectively. The advantages of topological Dirac anode over conventional metal- and graphene-based TECs are revealed. This work opens an exciting route toward high-performance energy converters via the union of topological material and thermionic devices.

An optimized design approach for 8-bit pipelined ADC using high gain amplifier

Demand of high-performance converters with integrated circuits with combined features and specifications of power consumption, resolution and speed have become very dominant in many emerging applications. Pipelined ADC mixed signal system consists of Sample and Hold, Flash ADC, DAC and Gain amplifier in all the stages. In the present work, a pipeline ADC architecture has 3-stages, with each stage of 3-bits with 3-bit flash ADC followed by a 3-bit binary weighted DAC at each stage. A novel approach to design a 8-bit ADC is implemented, and this design offers less number of comparators compared to flash ADC with less circuit complexity, and 8-bit ADC is designed with improvement in resolution. It is simulated first in MATLAB, but applying 1.8Volts sinusoidal and sampling time of 40 MSPS and clock frequency 10MHz the individual blocks are implemented in LT-spice 180 nm technology with bandwidth of 40 MHz. Then a high gain amplifier is implemented by using Diode connected load differential amplifier with 10mv input voltage and 18Mhz input frequency.

Prospects of Wireless Energy-Aware Sensors for Smart Factories in the Industry 4.0 Era

Advanced sensors are becoming essential for modern factories, as they contribute by gathering comprehensive data about machines, processes, and human-machine interaction. They play an important role in improving manufacturing performance, in-factory logistics, predictive maintenance, supply chains, and digitalization in general. Wireless sensors and wireless sensor networks (WSNs) provide, in this context, significant advantages as they are flexible and easily deployable. They have reduced installation and maintenance costs and contributed by reducing cables and preinstalled infrastructure, leading to improved reliability. WSNs can be retrofitted in machines to provide direct information from inside the processes. Recent developments have revealed exciting possibilities to enhance energy harvesting (EH) and wireless energy transmission, enabling a reliable use of wireless sensors in smart factories. This review provides an overview of the potential of energy aware WSNs for industrial applications and shows relevant techniques for realizing a sustainable energy supply based on energy harvesting and energy transfer. The focus is on high-performance converter solutions and improvement of frequency, bandwidth, hybridization of the converters, and the newest trends towards flexible converters. We report on possibilities to reduce the energy consumption in wireless communication on the node level and on the network level, enabling boosting network efficiency and operability. Based on the existing technologies, energy aware WSNs can nowadays be realized for many applications in smart factories. It can be expected that they will play a great role in the future as an enabler for digitalization in this decisive economic sector.

Constant-Current Gate Driver for GaN HEMTs Applied to Resonant Power Conversion

New semiconductor technology is enabling the design of more reliable and high-performance power converters. In particular, wide bandgap (WBG) silicon carbide (SiC) and gallium nitride (GaN) technologies provide faster switching times, higher operating temperature, and higher blocking voltage. Recently, high-voltage GaN devices have opened the design window to new applications with high performance and cost-effective implementation. However, one of the main drawbacks is that these devices require accurate base current control to ensure safe and efficient operation. As a consequence, the base drive circuit becomes more complex and the final efficiency is decreased. This paper presents an improved gate driver circuit for GaN devices based on the use of a constant current regulator (CCR). The proposed circuit achieves constant current regardless of the operating conditions, solving variations with temperature, aging and operating conditions that may degrade the converter performance. Besides, the proposed circuit is reliable and cost-effective, being applicable to a wide range of commercial, industrial and automotive applications. In this paper, its application to a zero-voltage switching resonant inverter for domestic induction heating was performed to prove the feasibility of this concept.

Modeling and Design of High Performance Converters for Optimal Utilization of Interconnected Renewable Energy Resources to Micro Grid with GOLRS Controller

This paper proposes a bidirectional Z-source dc-dc converter topology for the optimal utilization of renewable energy sources to the microgrid with the proposed control technique. Compared to the existing dc-dc converter circuits, they can reduce in-rush and harmonic current, provide larger range of output dc voltage and improve reliability. It can operate in voltage-fed and current-fed when the place of the source and load is exchanged each other, and it can be perform buck-boost function in these two conditions. Its power flow can be bidirectional. The bidirectional Z-source dc-dc converter is revealed with the consideration of enhanced converter efficiency, effective utilization of renewable energy sources and reduced switching losses. The proposed control technique is the combination of both the grasshopper optimization algorithm (GOA) and local random search (LRS) and hence it is known as GOLRS controller. Here, the searching behaviour of the GOA is enhanced by LRS with the help of two operators named as crossover and mutation. In the proposed technique, the GOLRS is used to generate the optimal gain dataset based on the minimum error objective function and select the exact gain parameter of the PI controller. Batteries are used as an energy source to balance out and allow the renewable power system units to continue running at a steady and stable output power. The proposed technique is executed in the MATLAB/Simulink working platform and compared with various existing techniques.

Robust optimal utilization with a grid‐connected microgrid using EFO‐GBDT based controller technique with integrated converters

AbstractThis paper proposes the model and design of optimal utilization of grid connected Micro Grid (MG) system with Enhanced Fruit fly Optimization with Gradient Boosting Decision Tree (EFO‐GBDT) based controller technique. The integration (modeling and design) of high performance converter topology is formulated with the consideration of enhanced converter efficiency, effective implementation, source of renewable energy and reduced swapping loss. In the proposed technique the control scheme is used to consolidate the performance of both an EFO algorithm and also GBDT. In the proposed technique, the EFOA plays out an estimate method to initiate an exact control signal systems and accumulates the control signal database, an offline way of light in power variety between the source side (source of renewable energy and battery) and load side. The performance of dataset used to work as the GBDT mode for an online way and it leads to the control procedure in less performance time. In this proposed technique, an objective function is determined by the system, data subject to be an equality and inequality restrictions. The restrictions are the sources of renewable energy, power require the storage of an charged elements. A battery is implemented as source energy and it is used to permit and balance the renewable power system units and to keep running at a steady and balance output power. At that point the proposed model is performed based on MATLAB/Simulink, its working platform and the performance is assessed based on the existing techniques.

Modulated Model Predictive Control for Four-Leg Inverters With Online Duty Ratio Optimization

Conventional finite control set (FCS) predictive load-voltage control for four-leg inverters features simplification in digital implementation compared to its complex counterpart, three-dimensional space vector modulation. However, the FCS approach is typically characterized by a variable switching frequency, low steady-state performance, and a higher average switching frequency in the neutral leg than the other three legs. To overcome these shortcomings, an online duty-cycle-optimization based model predictive control technique is proposed in this article. The performance of the inverter is evaluated experimentally in terms of load voltage tracking in different operating conditions such as nonlinear loads and balanced/unbalanced references. The proposed technique fulfills the requirement of a high-performance converter, constant switching frequency, and enhanced load voltage tracking at a lower sampling rate and, thus, solves the drawbacks of the conventional FCS model predictive control for a four-leg inverter. Furthermore, the proposed approach can facilitate the overmodulation operation, which is desirable for this type of power converters under nonlinear and unbalanced loading conditions.

Design of High Performance Converter for PMSM Applied to Flywheel Energy Storage Array

A multi-objective visual design method of permanent magnet synchronous motor (PMSM) drive system which is applied to flywheel energy storage array is proposed. D-partition technique is applied to obtain the parameters stable region. Besides, frequency-domain specifications such as gain margin and phase margin, time-domain specifications such as overshoot and settling time are considered. Furthermore, a parameters design method is proposed and the optimized performance can be derived which meets the time- and frequency-domain specifications simultaneously. Simulation and experimental results verify the effectiveness and practicability.

Online Fault Diagnosis Method for High-Performance Converters Using Inductor Voltage Polar Signatures

Recently, the high-performance converter with wide range and high gain has been widely used in these cases such as PV power generation. On the other hand, there are more highly variable stresses on switch and diode in high-performance converter than the traditional DC-DC converters due to the wide range and high gain. Therefore, it is necessary to diagnose switch and diode faults in high-performance converter. In this paper, the switch and diode fault are analyzed and compared with traditional DC-DC converters. Then, an online diagnosis technique based on the inductor voltage polarity of the DC-DC converter is proposed. This technique only uses the inductor voltage polarity and the switch gate drive signal as signatures to diagnose short-circuit or open-circuit fault of the switch and diode. The technique is cost-effective and simple because it uses simple auxiliary windings to sense the inductor voltage polar and uses some logic circuit to generate indicators. The details of the technique are discussed through an example of the quadratic Boost converter. Experiments illustrate the correctness of the proposed technique and show its capability for switch and diode fault diagnosis.

High-Performance Converters for Optimal Utilization of Interconnected Renewable Energy Resources: A Proposed AGORNN Controller

In most of the industrial applications, an interleaved buck converter is used due to its limited requirements of filter and the enhanced converter dynamic. However, it suffers from an extremely small duty ratio when the high voltage ratio is required. To overcome the above drawbacks, a series capacitor buck converter was introduced. Based on the series capacitor converter model, a high-performance buck converter is proposed in this paper. In this paper, a high-performance converter is designed for the optimal utilization of interconnected renewable energy sources with the proposed control technique. The model and design of high-performance converter is revealed with the consideration of enhanced converter efficiency, effective utilization of renewable energy sources and reduced switching loss. The proposed control technique is the organized execution of both the adaptive grasshopper optimization algorithm and recurrent neural network (AGORNN). Here, the searching behavior of the grasshopper is modified by using the search functions like crossover and mutation. In the proposed technique, the adaptive grasshopper optimization algorithm (AGOA) is utilized to generate the optimal gain dataset based on the objective of minimum error function. The accomplished dataset is used to train the recurrent neural network (RNN) and it leads to predict the exact gain parameter for the PI controller. Batteries are used as an energy source, to balance out and allow the renewable power system units to continue running at a steady and stable output power. The proposed model is executed in MATLAB/Simulink working platform, and the execution is assessed with the existing techniques.

Stability Analysis and Auto-Tuning of Interlinking Converters Connected to Weak Grids

This paper presents an adaptive multi-loop control scheme for inverters interlinking dc voltage sources to single-phase, low-voltage ac grids. Control self-adaptation is particularly useful in the case of weak grids that, due to frequent physical modifications (e.g., network reconfigurations and disconnection of generators/loads) and intrinsic lack of inertia, present strongly time-variant characteristics. The solution presented in this paper is based on a high-performance converter controller with auto-tuning capabilities. It is shown that the applied auto-tuning method can significantly widen the stability region of the interlinking converter, covering a broad range of grid impedance values. In addition, within the stable region, the controller maintains the nominal performance. Experimental results are reported validating the proposed approach in realistic operating conditions, including grid voltage distortion and variations of amplitude and frequency.

Wide-Bandwidth, High-Linearity, 2.8-GS/s, 10-bit Accurate Sample and Hold Amplifier in 130-nm SiGe BiCMOS

This paper presents a highly linear BiCMOS sample and hold amplifier (SHA) providing 2.8-GS/s intermediate frequency (IF) sampling for a 1-GHz input bandwidth spanning from 1.5 to 2.5 GHz. A single-transistor hold-mode feedthrough cancellation technique is implemented to remove distortion resulting from the nonlinear parasitic capacitance at the sampling node. The SHA is designed in a mainstream 130-nm BiCMOS technology using SiGe heterojunction bipolar transistors to buffer and sample the wideband input. The proposed SHA enables monolithic integration with a high-speed analog-to-digital converter core to realize a high-performance converter solution. This independent sampling front end occupies a core chip area of 0.6 mm2 and consumes an average power of 1.26 W. The SHA is a pseudo-differential open-loop design that includes two cascaded track-and-hold amplifiers, a high-speed clock driver, and externally adjustable current mirror biases. The high-speed clock drivers and buffers add 170 mW to the total power consumption. The measurements of the fabricated SHA show a 10-bit effective resolution across the 1-GHz IF bandwidth and < −61-dBc HD2 and HD3.

Fully digital routing logic for single-photon avalanche diode arrays in highly efficient time-resolved imaging

Time-correlated single-photon counting (TCSPC) is a powerful optical technique, which permits recording fast luminous signals with picosecond precision. Unfortunately, given its repetitive nature, TCSPC is recognized as a relatively slow technique, especially when a large time-resolved image has to be recorded. In recent years, there has been a fast trend toward the development of TCPSC imagers. Unfortunately, present systems still suffer from a trade-off between number of channels and performance. Even worse, the overall measurement speed is still limited well below the saturation of the transfer bandwidth toward the external processor. We present a routing algorithm that enables a smart connection between a 32×32 detector array and five shared high-performance converters able to provide an overall conversion rate up to 10 Gbit/s. The proposed solution exploits a fully digital logic circuit distributed in a tree structure to limit the number and length of interconnections, which is a major issue in densely integrated circuits. The behavior of the logic has been validated by means of a field-programmable gate array, while a fully integrated prototype has been designed in 180-nm technology and analyzed by means of postlayout simulations.

Development of a Wireless Low Power Datalogger with High Performance Converter

In this work, a low power datalogger with a wireless connection is described. The datalogger can be used as a portable and stand-alone device, as well as a wireless sensor network node. A flexible architecture, which combines a microcontroller with external local buses (data and address) and a complex programmable logic device (CPLD), has been used. The system has two special characteristics: one of them is the high resolution of A/D converters; the second is based on the incorporation of a non-volatile random-access memory (NVRAM) that allows fast access to stored data and a low consumption. Storing data in an NVRAM implies an extra security level for the maintenance of data even when the batteries of the system have been exhausted. The complete glue logic has been integrated into a Zero-Power CPLD in order to reduce size. In addition, in each specific application, the CPLD allows the implementation through hardware of some interfaces to sensor module, saving computation time.DOI: http://dx.doi.org/10.5755/j01.eee.21.3.10044

Comparative Performance Analysis of High Density and Efficiency PFC Topologies

In this paper, the efficiency and power factor performance of improved power factor correction (PFC) topologies suitable for a high density and efficient design are compared. Several topologies, including a conventional average current mode control boost PFC, an interleaved boost PFC, a back-to-back bridgeless boost PFC, and a semi-bridgeless boost PFC, are assessed through loss analysis and simulation using whole height 1 U and 2 kW class prototypes. Based on this, an optimal topology is selected for which an additional comparative analysis involving input line measure improvement control is conducted. The results of these experiments can be adapted for use in the circuit selection of high-performance converters with power factor improvement circuits.

Multi-Input Boost Converter for Hybrid PV and Wind Generator Systems

A renewable energy source that works alone can’t achieve customers’ requirements for a stable power supply. Therefore, the paper proposes a multi-input converter for hybrid renewable energy system. This converter is designed for two input sources, PV and wind generator in order to design high efficiency and high performance converters for renewable energy applications. The proposed multi-input converter is composed by interleaved technique with two step-up converters and the two inputs are accommodated with some extra semiconductors, inductances and diodes. The modes of operation based on the status of the four switches, where S1 and S2 operate as main switches in order to deliver energy from both voltage sources. A constant output power to the load is provided by switching S3 switch, which guarantied the appropriate output voltage by reduce the ripple and improve the reliability. Simulations of multi-input converter has been performed using MATLAB/SIMULINK. The simulation results confirm the validity of the proposed method, which can be seen as a promising new topology that ensure multi-input converter suitable for renewable energy applications.

Development of a High-performance Optical System and Fluorescent Converters for High-resolution Neutron Imaging

Abstract Two novel devices for use in neutron imaging technique are introduced. The first one is a high-performance optical lens for video camera systems. The lens system has a magnification of 1:1 and an F value of 3. The optical resolution is less than 5 μm. The second device is a high-resolution fluorescent plate that converts neutrons into visible light. The fluorescent converter material consists of a mixture of 6 LiF and ZnS(Ag) fine powder, and the thickness of the converter is material is as little as 15 μm. The surface of the plate is coated with a 1 μm-thick gadolinium oxide layer. This layer is optically transparent and acts as an electron emitter for neutron detection. Our preliminary results show that the developed optical lens and fluorescent converter plates are very promising for high-resolution neutron imaging.

Research on ultrafast wavelength conversion device by using tellurite glass

In the wavelength-division multiplexing network, high-performance optical wavelength converters are desired. This article will report very stable second harmonic generation by using tellurite glasses, second harmonic generation comparison in glass materials, and time-dependent change of second harmonic generation. We obtained 9 times larger second harmonic generation using TeO2 (60 mol%)–WO3 (30 mol%)–Bi2O3 (10 mol%) than using TeO2 (60 mol%)–WO3 (30 mol%)–PbO (10 mol%) glass. This value corresponds to 4.6 times higher than d11 constant of Y-cut quartz (0.4 pm/V). We have succeeded permanent poling by measurement of time-dependent change of second harmonic generation because there could not be found second harmonic generation intensity change after 6 months of poling at room temperature, and there was no decay of second harmonic generation intensity after 4 h of heating at 100°C.