Mode Power Converters Research Articles

Performance optimization of MASnI3 perovskite solar cells: Insights into device architecture

Recent research has focused an extensive amount of attention on the lead-free substance lead-free methylammonium tin(Sn) tri-iodide (MASnI3), which has emerged as a highly potential absorber layer in the structure of the device. Because it has a larger visible absorption spectrum and a shorter band gap of 1.3 eV than the lead halide perovskite, MASnI3 is a potential alternative to MAPbX3. Through numerical simulation, the different parameters on the device performances are fully investigated. We achieved an open-circuit voltage (Voc) of 0.93 V, a short-circuit current density (Jsc) of 22.20 mA/cm2, a fill factor (FF) of 78.81 %, and a power conversion efficiency (PCE) of 16.39 % using the optimised conditions. It demonstrates the huge potential of recently created lead-free perovskite solar cells and opens up a large dimension of opportunities for the creation of novel perovskite solar cells with a variety of photovoltaic applications. The amalgamation of the Tungsten Disulfide (WS2) material layer between the electron transport layer (ETL) and the absorber layer raised the device module's power conversion efficiency to 20.36 %.

Examining the effect of different photovoltaic modules on cucumber crops in a greenhouse agrivoltaic system: A case study

Agrivoltaic systems, a fusion of agriculture and photovoltaic (PV) technology, have emerged as a sustainable solution to optimise land use by enabling simultaneous solar energy and agricultural harvesting. The experiments were conducted in a polytunnel greenhouse in Kfar Qara, Israel, deploying three types of semi-transparent solar PV panels—bifacial glass-encapsulated silicon, bifacial plastic-encapsulated silicon, and semi-transparent organic photovoltaics (OPVs) installed above the plant canopy. The impact of these PV treatments on cucumber crops was evaluated and juxtaposed against a control greenhouse with no panels, over the spring season from February to June 2022. Key growth and yield metrics were recorded during 17 harvests between April 10 and June 2, 2022. The findings revealed a negligible decline in crop yield across PV panel treatments compared to the control. Notably, the control and glass-encapsulated silicon PV treatments demonstrated an increase in yield, growth, and fruit quality. Moreover, the glass-encapsulated silicon PV panels outperformed the plastic-encapsulated and OPV module power conversion in the high heat and humidity of the greenhouse environment. This study accentuates the potential of integrating glass-encapsulated silicon PV panels in polytunnel greenhouses, heralding a promising avenue for bolstering agrivoltaic applications by ensuring a harmonious balance between agricultural yield and electrical energy production.

PwrSoC’23 Focuses on Miniaturization of Power Conversion Solutions On-Chip, In-Package, and Module

PwrSoC’23 Focuses on Miniaturization of Power Conversion Solutions On-Chip, In-Package, and Module

Extended Physics-Informed Neural Networks for Parameter Identification of Switched Mode Power Converters with Undetermined Topological Durations

Extended Physics-Informed Neural Networks for Parameter Identification of Switched Mode Power Converters with Undetermined Topological Durations

A Delta-Sigma Modulated Power Converter With Inherent Zero-Voltage Switching

A Delta-Sigma Modulated Power Converter With Inherent Zero-Voltage Switching

Design and Implementation of Closed Loop SEPIC Converter for PV System Based Smart Home Application

The design, simulation, and analysis of the Single- ended primary-inductor converter (SEPIC), one of the least known Switch mode power converters, are presented in this study. By adjusting the switching element's duty cycle, this dc-dc converter may be utilized as a buck-boost converter. With minimal strain on components, SEPIC offers the specific benefit of offering positive polarity output voltage and ripple-free input and output current. This contrasts with conventional buck-boost converters, which have negative polarity output voltage along with extremely irregular currents and increased component stress. This makes it perfect for both commercial and personal uses, such as smart home gadgets that use PV energy. Under various input circumstances, extensive simulation has been performed in continuous conduction mode (CCM) utilizing SIMULINK-MATLAB. A PI controller has been added to optimize the responsiveness, reduce steady state error, and keep the output voltage constant. The SEPIC converter's hardware implementation verifies the simulation's findings.

A self-stabilizing point absorber wave energy converter with a top-shaped buoy and non-linear power take-off for oceanographic applications

Point absorber wave energy converters (PA-WECs) are considered an independent renewable energy resource in oceanographic research to study wave climate data, ocean navigation and maritime security. Their performance enhancement through optimally designed floats and power take-off (PTO) is a crucial challenge. The proposed study investigates the combined PA-WEC model, including (i) the hydrodynamic of the optimally designed top-shaped buoy, (ii) non-linear characteristics of power take-off and (iii) self-stability of PA-WEC under the real-time wave climate of XiaoMaiDao wave station, Shandong, China. The proposed mechanical power take-off comprises a double-sided rack with gear transmission and three-phase DC generators. The components of the power take-off are symmetrically oriented on both sides of the rack to make it statically and dynamically balanced for the self-stability of the PA-WEC. The floating buoy absorbs kinetic energy from waves relative to a fixed point and transfers it to the PTO system. The PTO module alters the forward and reverted strokes of heaving motion into uni-directional rotations on the output shaft, employing a mechanical gearing mechanism with one-way bearings. Subsequently, supercapacitors store the rectified electrical energy in the power conversion and storage modules. The mechanical power take-off was initially modeled in MATLAB/Simscape and verified through experimental investigations using mechanical testing and sensing machine. Secondly, the hydrodynamics of the floating buoy was studied using frequency- and time-domain simulations in ANSYS AQWA. Thirdly, the wave tank tests were performed on a 1:25 scaled buoy in a wave tank, and the test results were validated against the time-domain simulations. Finally, the combined effects of power take-off and buoy were studied on the prototype scale, and it is concluded that at 1m significant wave height, the power take-off system integrated with the Cyl-AS buoy can generate 247.76W (RMS) with PTO efficiency of ηpto_rms = 76.37% at PA-WEC efficiency of ηwec_rms = 12.10%. Installing the proposed point absorber wave energy converter system along the offshore platforms can promote the UN-SDG-2030 Agenda, specifically the 7 and 14 goals, by supplying electricity for oceanographic applications.

Development of high-precision hardware and software tools for automated determination of the characteristics of thermoelectric devices

In this work, a high-accuracy setup was developed for the characterization of thermoelectric devices in the temperature range of 300-900 K. The output parameters of the thermoelectric devices, including the thermoelectric efficiency Z, Seebeck coefficient S, and internal resistance r, were measured. A technique, block diagram, and computer tools for automated measurement and preliminary processing of experimental data were developed for automated studies of the properties of semiconductor materials and thermoelectric power conversion modules. The developed tools were shown to have high efficiency. The complexity of the process of measuring the main electrical parameters of semiconductor materials was significantly reduced, and the accuracy of the obtained results was increased.

Design of a Power Converter for Solar Energy Storage System

This paper presents a single-stage three-port isolated power converter that enables energy conversion among a renewable energy port, a battery energy storage port, and a DC grid port. The proposed converter integrates an interleaved synchronous rectifier boost circuit and a bidirectional full-bridge circuit into a single-stage architecture, which features four power conversion modes, allowing energy adjustment for both the renewable energy and the battery storage energy ports when power is supplied by the renewable energy port. It also features bidirectional functionality that allows the battery storage energy port to provide energy storage through the DC grid port, thereby providing uninterrupted power supply functionality. The converter uses four power switches and two inductors to boost and convert energy from the renewable energy port to the battery storage energy port or to the DC grid port through the bidirectional full-bridge circuit. The converter is also capable of 1 kW power energy conversion by utilizing an adjustable duty cycle with a fixed frequency of 100 kHz and phase-shift control through a built-in pulse width modulation control module of a TMS320F28 series digital signal processor. According to the experimental results, the converter developed in this study can achieve a conversion efficiency of up to 94%.

Design and Optimization of an Integrated Resonant Inductor With High-Frequency Transformer for Wide Gain Range DC–DC Resonant Converters in Electric Vehicle Charging Applications

Large-scale adoption of wide band gap semiconductors in switched mode power converters enables miniaturization of power electronic systems. With switching frequencies approaching a few hundred kilohertz - megahertz range, efficient and compact design of magnetic components are crucial for future generation power supplies in data centers or electric vehicle (EV) applications. In a typical two-stage AC-DC power supply, the DC-DC stage is often constructed using a resonant converter with galvanic isolation provided by a high-frequency transformer. In such systems, the integration of an inductor in the resonant network with the transformer helps improve power density and reduces component count and cost. However, the integration of magnetic components can result in increased losses, deteriorating the performance of the power conversion system. In this paper, a magnetic structure along with an optimization methodology is presented to integrate a predefined resonant inductor as leakage inductance of the high-frequency transformer achieving minimum penalty on converter efficiency using planar core geometry and printed circuit board (PCB) based windings. The proposed methodology is applied to integrate a <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$7.8 \mu \rm{H}$</tex-math></inline-formula> inductor with a 2:1 transformer for a 6.6 kW, 500 kHz LCL-T resonant DC-DC stage utilizing GaN transistors in an onboard battery charging converter. On the prototype converter using the optimized integrated magnetic component, a peak efficiency of 98.4% was obtained using PCB windings. Furthermore, the integrated magnetic component achieved 64 kW/L power density in the demonstrator prototype.

A Reconfigurable Setup for the On-Wafer Characterization of the Dynamic RON of 600 V GaN Switches at Variable Operating Regimes

Charge-trapping mechanisms observed in high-voltage GaN switches are responsible for the degradation of power converter efficiency due to modulation of the effective dynamic ON-resistance (RON) with respect to its static value. Dynamic RON degradation is typically dependent on the blocking voltage and the commutation frequency and is particularly significant in new technologies under development. The possibility to characterize this phenomenon on GaN switch samples directly on-wafer, under controlled operating conditions that resemble real operations of the DUT in a switching mode power converter is extremely valuable in the development phase of new technologies or for quality verification of production wafers. In this paper, we describe a setup that allows this characterization: dynamic RON degradation of on-wafer 600 V GaN switches is characterized as a function of the VDS blocking voltage, the VGS driving voltage, and at different temperatures. The dependency on the switching frequency is identified by measuring the current recovery of the switch after the application of blocking voltages of different durations.

Bidirectional Power Converter Module (PCM) for Advanced Vehicle Electrification

This research paper shows a Bidirectional Power converter Module (PCM) with an isolation transformer capable of performing diverse functionalities critical for vehicle electrification. The PCM is designed to enable Charging in systems involving grid-connected topologies for its regenerative capabilities, and bidirectional power flow functionality. This versatile converter is capable of giving various types of power outputs. Through modular configurations of PCMs, a wide range of voltage and power ratings can be achieved. The paper thoroughly elucidates the control algorithms for each operational mode, encompassing various grid functions. The simulation results aim to verify the performance of the converter. To attain high power density, the design incorporates SiC MOSFET power modules with high-frequency switching, complemented by an isolation transformer featuring a nanocrystalline core. In essence, this article presents a promising converter topology that provides many practical and relevant capabilities for the advancement of electric vehicles.

Research on Displacement Measurement and Self-detecting Circuit Based on LVDT

A Liner Variable Differential Transformer (LVDT) measuring system and self-detecting circuit are proposed for micro-displacement measurement, which can detect the displacement of LVDT and monitor the fault signals simultaneously. The circuit is composed of a focusing mechanism, a displacement measurement module, a correction module, a monitoring module, an AD conversion module, a drive module, a control module and a power conversion module. Due to the requirements of high reliability and long life of space remote sensing system, as well as the radiation influence in space, LVDT measurement and control data need to be monitored and validated. The displacement signal output of LVDT is an important signal quantity for fault detection and closed-loop control of the system. By analysing the displacement signal and drive output signal of LVDT, fault modes such as mechanism stuck-up and mechanism disconnection are detected. Aiming at the limitation of current detection methods, this paper proposes a method of detecting LVDT signal. Circuit protection is added to the circuit to improve the reliability of the circuit. The linearity and fault detection ability of the circuit are tested and analysed.

Design of Spaceborne Stepper Motor Driver Based on FPGA

In order to meet the specific application requirements of stepper motor in space optical remote sensor, such as large load current, low operating frequency, sufficient safety margin, anti radiation and other space environment indicators, a spaceborne stepper motor driver based on antifuse Field Programmable Gate Array (FPGA) is designed. The driver consists of power conversion module, control module, drive module, and position detection module. Using P-channel Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET) and N-channel MOSFET to design bipolar drive circuit, the driver hardware circuit is simple and the software resource occupancy rate is low. Through the experiments of the dual functions of logic protection circuit in hardware and dead zone protection in software, it is verified that the design of spaceborne stepper motor driver based on FPGA meets the requirements of space optical remote sensor mechanism control.

Which Came First? Part II [White Hot

<fig orientation="portrait" position="float" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <graphic orientation="portrait" position="float" xlink:href="rober-3218356.tif"/> </fig> In my previous column, I started by asking which led the way in the advancement of power electronics technology—devices or topologies? I then reviewed the early history of “switched mode power conversion,” given that converters that used electromechanical switches like vibrators were switched mode power. That column ended with a discussion of the developments in power electronics in the 1960s after the first solid state switches started becoming generally available.

A High-Performance Pll Observer for Sensorless Three-Phase Induction Motor Control

This paper presents an enhanced estimation algorithm based on the PLL (phase-locked loop) approach, which is used to estimate the rotor speed in induction motors (IM) drives. It can be challenging to obtain an accurate estimate during frequency ramps using existing PLL schemes. Thus, the performance of PLL schemes can be degraded during the acceleration and deceleration operations when applied to motor drives. In addition, the performance of conventional PLL scheme estimation is negatively affected by disturbances, for example, DC offsets. One of the novelties of the proposed speed observer (HPPO - High-Performance PLL Observer) is error normalization, which is based on the currents and a mechanism of variable gain based on the reference speed. The reference speed is also used to build an additional feedforward adjustment action. These modifications improve estimator results during load insertions and at low rates. In order to validate the proposed HPPO algorithm, it is implemented experimentally in a laboratory prototype using a 2.2kW IM. The motor is driven by a three-phase pulse width modulation (PWM) power converter, which is controlled by a DSP TMS320F28069. Numerical analysis and experimental results are carried out to validate the proposed scheme's high performance.

Ammonia for post-healing of formamidinium-based Perovskite films

Solvents employed for perovskite film fabrication not only play important roles in dissolving the precursors but also participate in crystallization process. High boiling point aprotic solvents with O-donor ligands have been extensively studied, but the formation of a highly uniform halide perovskite film still requires the participation of additives or an additional step to accelerate the nucleation rate. The volatile aliphatic methylamine with both coordinating ligands and hydrogen protons as solvent or post-healing gas facilitates the process of methylamine-based perovskite films with high crystallinity, few defects, and easy large-scale fabrication as well. However, the attempt in formamidinium-containing perovskites is challenged heretofore. Here, we reveal that the degradation of formamidinium-containing perovskites in aliphatic amines environment results from the transimination reaction of formamidinium cation and aliphatic amines along with the formation of ammonia. Based on this mechanism, ammonia is selected as a post-healing gas for a highly uniform, compact formamidinium-based perovskite films. In particular, low temperature is proved to be crucial to enable formamidinium-based perovskite materials to absorb enough ammonia molecules and form a liquid intermediate state which is the key to eliminating voids in raw films. As a result, the champion perovskite solar cell based on ammonia post-healing achieves a power conversion efficiency of 23.21% with excellent reproducibility. Especially the module power conversion efficiency with 14 cm2 active area is over 20%. This ammonia post-healing treatment potentially makes it easier to upscale fabrication of highly efficient formamidinium-based devices.

Development of a Fault-Diagnosis System through the Power Conversion Module of an Electric Vehicle Fast Charger

The supply of electric vehicles (EVs), charging infrastructure, and the demand for chargers are rapidly increasing owing to global low-carbon and eco-friendly policies. As the maintenance of charging infrastructure varies depending on the manufacturer, fault detection and maintenance cannot be conducted promptly. Consequently, user inconvenience increases and becomes an obstacle to EV distribution. Recognizing charger failure after occurrence is a management method that is not economically effective in terms of follow-up. In this study, a data collection system was developed to diagnose EV fast-charger failure remotely in advance. The power module failure-prediction and management system consists of an AC sensor, DC sensor, temperature and humidity sensor, communication board, and data processing device. Furthermore, it was installed inside the fast charger. Four AC inputs, four DC outputs, and temperature and humidity data were collected for 12 months. Using the collected data, the power conversion efficiency was calculated and the power module status was diagnosed. In addition, a multilayer perceptron neural network was used as an algorithm for training the classification model. Charging patterns according to normal and failure were trained and verified. Based on results, the pre-failure diagnosis system demonstrated an accuracy of 97.2%.

Scott-Tied Magnetically Linked Solar Multilevel Converter in Varying Environmental Conditions

Recently, multilevel converters (MLCs) have given promising solutions for medium-power and high-power renewable energy systems. However, voltage level enhancement leads to a higher device count, especially for three-phase configurations. A megawatt-scale three-phase 27-level converter with a Scott-connected arrangement is used for medium-voltage applications to address such issues. The Scott transformer uses 1:3:9 turn ratios between the windings to have 27-level output converter voltage with the advantage of two-phase to three-phase conversion. Moreover, the transformers enable the converter output voltage to medium-voltage levels (typically 11 to 33 kV). Traditional three-phase systems have cascaded power converter modules in each phase. However, this system provides an alternative solution for solar power injection into the grid with minimum cascaded voltage source converters forming a two-phase network. The quadrature displaced nearest level modulation strategy fundamentally switches phase A and B legs. Moreover, the solar photovoltaic (SPV) system is modeled at a megawatt-scale and tested in various environmental conditions. Thermal, cost, and leakage-inductance models are presented for the Scott-tied solar MLC. Obtained results demonstrate the satisfactory observation and control of the SPV system for renewable energy applications.

Design and Implementation of Synchronous Buck converter for Space Applications

Abstract: The synchronous Buck converter is used to step down voltage from higher to lower level. Now a days, Efficiency is the major concern in designing any converters hence power converter design must be optimized to increase the performance of converter and to meet the requirement of load demand. The proposed work aims at design and Implementation of 6W synchronous buck converter using LT3845 synchronous step-down controller IC which is suitable for High Efficiency application. The compactness of device is also a major concern for proposed work, hence the current mode topology makes the power converter module more compatible and efficiency. The proposed work is designed for output power 12V/0.5A(6W) for an Input voltage from 24-30V.The system frequency of converter is 150Khz.The results are obtained for Hardware Implementation using LT3845 IC.