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Last Updated: 10 January 2023

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AC/DC Electric-Field-Assisted Growth of ZnO Nanowires for Gas Discharge

Using ZnO nanowires as needle anodes in a gas discharge is a smart way to ensure continuous discharge at a relatively low voltage. It is important that the ZnO nanowires are spaced enough apart to ensure no electric field erosion is occurring, and that the nanowire anodes are easy to assemble together with the discharging units. The study that focused on growing ZnO nanowires on PCBs showed that for the first time, ZnO nanowires on PCBs did not comply with the requirements of gas discharge; however, the ZnO nanowire growth parameters were not determined in this study.

Source link: https://doi.org/10.3390/ma16010108


Voltage Stability Assessment of AC/DC Hybrid Microgrid

Since many types of power generators and loads coexist at the power distribution level, coordination between AC sub-microgrids and DC sub-microgrids enhances operational effectiveness. However, the voltage stability analysis and software validation of AC/DC hybrid microgrids is a critical concern, particularly with the increasing use of power electronics devices and various forms of power generation. We look at the simulation of AC/DC hybrid microgrids with grid-forming and grid-following power converters in this paper. To minimize simulation runtimes with acceptable errors, we recommend a rapid simulation system that minimizes the simulation runtime.

Source link: https://doi.org/10.3390/en16010399


AC-DC DAB Converter with Power Factor Correction

The converter converts behave as a resistive load when maintaining the output voltage constant when achieving a high power factor and low input current THD, according to the used modulation. The conversion is straightforward, as only two voltage sensors are required and no inner current loop is used.

Source link: https://doi.org/10.3390/en16010320


Coordination Control of a Hybrid AC/DC Smart Microgrid with Online Fault Detection, Diagnostics, and Localization Using Artificial Neural Networks

A solar and wind renewable energies-based hybrid AC/DC microgrid is suggested in this paper for minimizing the number of DC/AC/DC power conversion steps. MG volatility rises as a result of high penetration rates of renewable energy. Because of its high gain at the resonant frequency, the PR controller plays a key role as a digital filter with infinite impulse response characteristics, thereby lowering harmonics. Power electronic converters may experience excessive current in short circuit failures due to the usage of converter-connected DG units in MGs. Fault detection is critical for MG control and operation because it allows the system to quickly identify and recover from failures. Because of its flexibility, robustness, and quickness, this paper suggested an intelligent online fault detection, diagnosis, and localization information for hybrid low voltage AC/DC MGs using an artificial neural network.

Source link: https://doi.org/10.3390/electronics12010187


Power management with BMS to modified interlinking converter topology in hybrid AC/DC microgrid

In a hybrid AC/DC microgrid, this paper describes a battery management device for a modified interlinking converter. The power management scheme uses the BMS to prevent the battery operation in hazardous environments, thus increasing the battery bank's life cycle. The PMS for a hybrid microgrid operating in both grid-connected and standalone modes is based on this report. According to the operation mode, the upgraded interlinking converters are composed of an interlinking converter and a two-stage interlinking conversion-energy storage device. In the grid-connected mode, the ILC acts as a grid-support unit for both microgrids, while TSILC-ESD acts as a grid-support unit for both microgrids. In addition, the TSILC-ESD supports the AC microgrid. The results reveal an acceptable performance for the hybrid microgrid in both grid-connected and standalone modes, as well as a prompt BMS response under operating constraints.

Source link: https://doi.org/10.1016/j.egyr.2022.12.082


Effect of Electric-Field Components on the Flashover Characteristics of Oil-Paper Insulation Under Combined AC-DC Voltage

Two electrode models were investigated in this research, investigating the effects of electrical field and DC voltage components on the creepover characteristics of oil-paper insulation under combined AC-DC voltage is investigated. The flashover voltage under the influence of a strong parallel electric field component is about 1. 2 times higher than that under the influence of a high normal electric field component, according to the study. When the DC voltage component value rises under the influence of a robust normal electric field component, the value of the corresponding AC voltage component of the creepage flashover voltage trend follows a decreasing trend. The distribution of carbonized particles on the surface of the insulating pressboard after creepage flashover is variable under the influence of the DC voltage component and the presence of space charge on the insulating pressboard.

Source link: https://doi.org/10.1109/ACCESS.2022.3233082


Modified average‐value model for high‐performance fault transient simulation of AC‐DC hybrid power networks

The analysis of AC/u2010DC hybrid power systems requires both effective and precise electromagnetic transient simulation, due to the complex transients and the possibility of transition from a minor fault in AC subsystems to a catastrophic blocking event of a high-voltage directu2013current transmission line. This paper discusses the model's deficiency and discusses the application of the averageu2010value model in the computerization of the LCC's 2010HVDC system. In the transition between normal and defective operation, a modified interface and the associated softu2010switching procedure are suggested for increasing the simulation results of the LCC-HVDC model.

Source link: https://doi.org/10.1049/rpg2.12437


Equal‐area criterion and analytical model for transient stability assessment of hybrid AC–DC transmission system using voltage sourced converter

The equal u2010area criterion, as reported from the transient stability analysis of AC power systems, has been redeveloped for ACu2013DC power systems based on the voltage sourced converter and, in particular, the modular multilevel converter. Through symbolic measurements for the most common DC and AC short circuit faults, the most demanding resolution angle and the critical clearing time are determined. The effect of scheduled power flows on DC versus AC lines on the transient stability is investigated as an illustrative example.

Source link: https://doi.org/10.1049/rpg2.12574


Investigating the input power quality of multi-pulse AC-DC power converter fed induction motor drives

It's always a difficult problem to determine the current total harmonic distortion of multi-pulse AC-DC power converter fed induction motor drive. The input power quality of IMD decreases as a result of the higher amount of supply. The production of current THD should be monitored in such a way that it meets IEEE-519's power quality requirement. With the increase of the pulse number of a multi-pulse AC-DC converter, current THD is increasing. This work will inform the industrial community of the correct choice of AC-DC power converter for IMD applications considering power quality and circuit configuration issues.

Source link: https://doi.org/10.1016/j.heliyon.2022.e11733


Analysis and Simulation Research of Cascading Faults in AC/DC Hybrid Grid

The traditional AC power grids are gradually evolving into AC/DC hybrid grids as a result of the introduction of power systems. Simulations based on PSCAD/EMTDC hardware were carried out to demonstrate the typical cascading fault scenario, including HVDC commutation loss, DC blocking, power flow transfer, incorrect relay protection, and network outage. Both analysis and simulation results indicate that the “stiffen; poor DC's poor AC” design and inaccurate coordination of relay protection and stability control equipment are among the key causes of cascading errors.

Source link: https://doi.org/10.1109/OAJPE.2022.3213242

* Please keep in mind that all text is summarized by machine, we do not bear any responsibility, and you should always check original source before taking any actions

* Please keep in mind that all text is summarized by machine, we do not bear any responsibility, and you should always check original source before taking any actions