Parallel Resonance Research Articles

Enhancing power quality: An Adaline algorithm for direct resonance current extraction in shunt active power filter

This paper presents an adaptive linear neuron (Adaline) algorithm designed to extract resonance current from the supply current directly. It aims to reduce the computation burden while upholding efficacy in the extraction process. The approach involves establishing the primary power system, evaluating harmonic and resonance current impacts, formulating efficient extraction strategies based on current waveform characteristics, employing the Adaline algorithm for extraction, and constructing a single-phase shunt active power filter (SAPF) to address harmonic currents and parallel resonance effects. Comparative analysis demonstrates the Adaline algorithm’s precision in extracting current amplitudes pre- and post-SAPF implementation. However, observed disparities in extracted resonance current amplitude may stem from the algorithm’s limitations in capturing low-amplitude signals. While a gain adjustment effectively boosts amplitude. However, it introduces considerable ripple and inconsistency, likely linked to parallel resonance effects. Notably, the SAPF exhibits simultaneous harmonic compensation and resonance damping capabilities. Results affirm the SAPF’s effectiveness in reducing harmonic components across all frequencies, including resonance frequency. Furthermore, resonance damping is crucial for further improving SAPF performance and reducing resonance current. This results in significantly improved waveform quality and reduced total harmonic distortion (THD) and individual harmonic distortion (THDi) values of compensated supply current.

Analysis of active impedance characteristics and harmonic deterioration of multiple grid connected inverters considering nonlinear factors

AbstractThe harmonic problems caused by non‐linear factors of the grid connected inverter (GCI) system are more complicated, including both non‐characteristic harmonics emitted by the dead‐time and the changes in harmonic impedance characteristics. Harmonics interact with the changing impedance, and even cause harmonic amplification and resonance. The harmonic deterioration of the multiple GCIs system is serious. To analyse the mechanism and way of harmonic deterioration in grid‐connected system caused by nonlinear factors, the active impedance models of single inverter and multiple GCIs system including dead‐time effect and digital control delay are established first. In view of this, the influence mechanism of non‐linear factors on system stability is explored. The improved modal analysis method is used to traverse the network series parallel resonance caused by nonlinear factors. The results show that both the dead‐time effect and digital control delay reduce phase margin of the system, resulting in the resonant frequency shift and the resonant peak increase. When the harmonic excitation source interacts with the complex network under the influence of nonlinear factors, it will lead to further deterioration of harmonics. Finally, based on the MATLAB and RT‐LAB hardware‐in‐the‐loop simulation platforms, a multiple GCIs system model is built to verify the correctness of the established active impedance model and harmonic deterioration analysis.

Resonance Suppression Method Based on Hybrid Damping Linear Active Disturbance Rejection Control for Multi-Parallel Converters

The parallel operation of multiple LCL-type converters will result in a deviation of the resonant frequency and resonance phenomena. The occurrence of harmonic resonance can cause problems such as an increase in harmonic voltage and current. This can lead to the malfunction of relay protection and automatic devices, causing damage to system equipment. In severe cases, it can cause accidents and threaten the safe operation of the power system. A hybrid damping active disturbance rejection control (HD-ADRC) method is proposed in this paper to suppress the harmonic resonance of parallel LCL-type converters. First, a third-order linear disturbance rejection controller (LADRC) including the linear extended-state observer and the error-feedback control rate is designed based on LCL-type converter model analysis. The proposed method considers the resonance couplings caused by both internal and external disturbances as the total disturbance, thus improving the anti-disturbance capabilities as well as the operational stability of converters in parallel. Then, a hybrid damping control is proposed to reconstruct the damping characteristics of converters to suppress the parallel resonance spike and reduce the resonance frequency offset. And the parameter selection of the control system is optimized through a stability analysis of the tracking performance and anti-disturbance performance of the HD-ADRC controller. Finally, all the theoretical considerations are verified by simulation and experimental results based on the Matlab/Simulink 2018B and dSpace platform. The simulation and experimental results show that the PI controller gives a THD of 5.33%, which is reduced to 4.66% by employing the HD-LADRC, indicating an improved decoupling between the converters working in parallel with the proposed control scheme.

Study on the suppression of parasitic resonance of film bulk acoustic wave resonators

To suppress the parasitic resonance of a film bulk acoustic resonator (FBAR) and meet the high-frequency requirements of 5G communication, an FBAR model was established based on COMSOL Multiphysics simulation software. The effects of the piezoelectric materials, electrode lateral size, electrode shape (rectangle, circle, trapezoid, and regular pentagon), and apodization angle (30°, 36°, 40°, and 45°) on parasitic resonance were studied, and the suppression effect of the step-load structure on lateral acoustic wave leakage was discussed. The simulation results show that the best suppression effect on parasitic resonance is achieved when the piezoelectric material is AlN, the electrode shape is a non-regular pentagon, and the apodization angle is 40°; when the resonant area is 3600μm2, its non-circularity is 6.45 %, which is equivalent to the rectangular electrode when the resonant area is 10000μm2. The designed electrode step-load structure improved the quality factor at the parallel resonance point. When the electrode lateral size is 60 μm, the quality factor of the second-order electrode load structure is 1378, which is 10.07 % higher than the quality factor of the electrode-free load structure.

Nonlinear metamaterials enhanced surface coil array for parallel magnetic resonance imaging

Magnetic resonance imaging (MRI) is a crucial medical imaging modality, with parallel MRI accelerating scans but often reducing the signal-to-noise ratio (SNR). Recent advances in metamaterials have shown considerable potential in enhancing the SNR of MRI and consequently improving the quality of parallel MRI. In this study, we present a nonlinear metamaterial comprising nonlinear meta-atoms designed to selectively enhance the radio-frequency reception field in MRI, while minimizing interference with the radio-frequency transmission field. We develop an electromagnetic field-circuit joint simulation process for analyzing and optimizing the nonlinear response. Experimental validation confirms that nonlinear metamaterial integration in a surface coil array delivers a 3-fold SNR increase for parallel MRI compared to using the surface coil array alone. This research advances our understanding of such metamaterials and demonstrates their potential for practical utilization in MRI and clinical settings, thereby promising substantial enhancements in imaging capabilities.

A Multiphase LCC-S Compensated Wireless Power Transfer System Based on Integrated Inversely Coupled Inductors and Parallel Resonance

A Multiphase <i>LCC</i>-S Compensated Wireless Power Transfer System Based on Integrated Inversely Coupled Inductors and Parallel Resonance

A digital twin for parallel liquid-state nuclear magnetic resonance spectroscopy

One approach to increasing nuclear magnetic resonance measurement sample throughput is to implement multiple, independent detection sites. However, the presence of radio frequency interference poses a challenge in multi-detector systems, particularly in unshielded coil arrays lacking sufficient electrical isolation. This issue can lead to unwanted coupling of inductive coils, resulting in excitation pulse interference and signal transfer among multiple detection sites. Here we propose a theoretical framework that combines electromagnetic simulation with spin-dynamic calculations. This framework enables the evaluation of coil coupling effects, the design of parallel pulse sequences to mitigate inter-channel coupling, and the separation of composite free induction decays obtained from multiple detectors. The parallel pulse compensation scheme was validated by a 2-channel parallel spectroscopy experiment. These results provide valuable insights for the design of parallel nuclear magnetic resonance hardware and for exploring the limits of parallelization capacity within a fixed magnet system.

Harmonic impedance optimization scheme for multi‐resonance systems to suppress resonance

AbstractHarmonic resonance is caused by harmonic source matching resonance frequency and presents the characteristics of decentralization and whole network in modern grids. The current resonance suppression methods mainly focus on reducing the harmonic source, and are suitable for single‐site and small‐scale grids. This paper presents a new method for suppressing parallel resonance at system level. The holistic harmonic resonance is suppressed by reducing the harmonic impedance. In addition, new resonances are prevented by weakening the coupling between resonance and non‐resonance frequencies. The resonance modal analysis and resonance frequency shift (RFS) are employed to optimize harmonic impedance. Simulation results indicate that the capacitance parameter has higher sensitivity and is theoretically more suitable for RFS. Considering the accuracy of modal frequency sensitivity, a variable‐limit genetic algorithm for iteration is proposed. The validity of the proposed method was verified using an IEEE 14‐bus test network.

Battery‐free ultra‐low‐power radio‐frequency receiver for mm‐wave applications using 130‐nm CMOS technology with harvested DC supplies

SummaryThis paper presents a battery‐free ultra‐low‐power (ULP), highly integrated, and wide‐bandwidth low‐IF radio‐frequency (RF) receiver designed for millimeter‐wave (mm‐Wave) applications, utilizing 130‐nm CMOS technology. The suggested RF receiver is suitable for K‐band (n258) at 26 GHz, Ka‐band (n261 and n257) at 28 GHz, and the LMDS band at 28 GHz in fifth‐generation applications. The proposed radio receiver consists of a low‐noise driver stage implemented using a complementary current‐reuse common gate with an active shunt feedback configuration and an in‐phase/quadrature‐phase (I/Q) demodulator. The proposed RF receiver employs transformer coupling to isolate the DC path between the transconductance stage (RF stage) and the switching stage (IF stage). The driver stage expands the RF input impedance while maintaining acceptable linearity and gain with ultra‐low DC power dissipation. The DC supplies for the proposed mm‐Wave RF receiver are generated using two novel energy‐harvesting voltage doubler circuits to provide positive and negative voltages. The proposed mm‐Wave radio receiver consumes 0.475 mW from a 1.1 V DC supply and exhibits a power conversion gain (CG) of 6.3 dB, with a 3 dB frequency bandwidth extending from 22 to 32 GHz. The input 1‐dB compression point (P1dB) of the RF receiver is −2.65 dBm, and the input third‐order intercept point (IIP3) is 7.35 dBm. With a sensitivity of −66.5 dBm at a 100 MHz channel bandwidth and a dynamic range of 63.85 dB, the suggested receiver demonstrates notable performance characteristics. The proposed radio receiver boasts an excellent figure of merit (FoM) at 215 dB, surpassing published works by a margin of 8–31 dB. The primary positive supply voltage is derived from a double‐band positive voltage doubler with series resonance feedback and parallel resonance networks, efficiently achieving the desired DC voltage and output current (1.1 V and 450 μA). Meanwhile, the negative gate bias is provided by a negative voltage doubler, ensuring the necessary negative voltage (−0.5 V) without any current conditions.

Experimental analysis of a multi-phase resonance-based fault current limiter prototype under symmetrical and asymmetrical faults

Expansion of power systems and involving more distributed generation cause to increase in fault current levels. This paper presents a three-phase resonance-based solid-state fault current limiter (FCL) prototype that has series and parallel resonance modes developed to suppress fault currents of power systems. The laboratory-scaled prototype is located on a three-phase test circuit and has been examined with the fault types of three-phase, three phase-to-ground, two phase-to-ground, and phase-to-ground. The performance and effectiveness of the proposed series-parallel resonance-type fault current limiter (SPRFCL) are validated with the comparison of Matlab/Simulink simulations and experimental test results. Fault currents in different types of faults are limited to an allowable value at high rates and experimental results are considerably close to current values obtained from each fault simulation. Fault currents of faulted phases are restricted with the limiting rates ranging from 75 % to 85 % concerning prospective fault currents in the non-FCL situations. Short-circuit test results of the prototype of SPRFCL that is supplied from a 380 V grid revealed that it acts stable and successful operation regardless of fault type. Accordingly, it has a favorable circuit design for power system applications.

DFUSNN: zero-shot dual-domain fusion unsupervised neural network for parallel MRI reconstruction

Objective. Recently, deep learning models have been used to reconstruct parallel magnetic resonance (MR) images from undersampled k-space data. However, most existing approaches depend on large databases of fully sampled MR data for training, which can be challenging or sometimes infeasible to acquire in certain scenarios. The goal is to develop an effective alternative for improved reconstruction quality that does not rely on external training datasets. Approach. We introduce a novel zero-shot dual-domain fusion unsupervised neural network (DFUSNN) for parallel MR imaging reconstruction without any external training datasets. We employ the Noise2Noise (N2N) network for the reconstruction in the k-space domain, integrate phase and coil sensitivity smoothness priors into the k-space N2N network, and use an early stopping criterion to prevent overfitting. Additionally, we propose a dual-domain fusion method based on Bayesian optimization to enhance reconstruction quality efficiently. Results. Simulation experiments conducted on three datasets with different undersampling patterns showed that the DFUSNN outperforms all other competing unsupervised methods and the one-shot Hankel-k-space generative model (HKGM). The DFUSNN also achieves comparable results to the supervised Deep-SLR method. Significance. The novel DFUSNN model offers a viable solution for reconstructing high-quality MR images without the need for external training datasets, thereby overcoming a major hurdle in scenarios where acquiring fully sampled MR data is difficult.

Numerical Extraction of the Equivalent Circuit for a Basic Magnetoelectric Dipole Antenna

Magnetoelectric dipoles have attracted global research attention due to its broadband, unidirectional, and high front-to-back ratio characteristics. This study implemented a co-simulation between a basic magnetoelectric dipole and its front feeding circuit through the step-by-step numerical extraction of its equivalent circuit model equipped with lumped and frequency-independent components. First, the series resonance subcircuit was derived from the series resonance point in the impedance of the magnetoelectric dipole. Second, the parallel resonance sub-circuit was achieved based on the parallel resonance point. By combining the series and parallel sub-circuits according to the sequence of their resonance frequency, the final form of the equivalent circuit for the basic magnetoelectric dipole was realized. Furthermore, to obtain the component values of the proposed circuit, a numerical fitting technique was adopted to accurately match the input impedance of the antenna and its equivalent circuit. A comparison of the circuit and antenna electromagnetic simulations showed that they agreed well with each other. Hence, the correctness and feasibility of the extraction process were verified. The overall results showed that the proposed circuit model can easily substitute for a basic magnetoelectric dipole in the implementation of antenna/circuit cosimulation in circuit simulators.

Design, Fabrication and Performance Analysis of a Portable, Antenna Analyzer Based, Quartz Crystal Microbalance Measuring System with Energy Dissipation

Impedance measurements play a critical role in analyzing the electrical behavior of piezoelectric biosensors in general. Antenna analyzers are engineered to measure the specific case of input impedance for antenna systems. In this study small form factor antenna analyzer is repurposed to work as driving circuit for a Quartz Crystal Microbalance (QCM) biosensor in combination with a single board computer as an indication of how small and portable an impedance measuring system can be made, while allowing monitoring of important parameters of series and parallel resonance frequencies together with dissipation factor. A QCM crystal with a 10 MHz fundamental resonance frequency is employed to determine the limit of detection of the system in Bovine Serum Albumin (BSA) and glycerol solutions. Dissipation factor and phase angle were monitored during the experiments. Limit of detection is 20 µg/ml BSA in phosphate buffer saline (PBS) and 250 µl of glycerol in 100 ml of deionized water.

Determination of Electrical and Mechanical Properties of Liquids Using a Resonator with a Longitudinal Electric Field

The possibility of determining the elastic modules, viscosity coefficients, dielectric constant and electrical conductivity of a viscous conducting liquid using a piezoelectric resonator with a longitudinal electric field is shown. For the research, we chose a piezoelectric resonator made on an AT-cut quartz plate with round electrodes, operating with a shear acoustic mode at a frequency of about 4.4 MHz. The resonator was fixed to the bottom of a 30 mL liquid container. The samples of a mixture of glycerol and water with different viscosity and conductivity were used as test liquids. First, the frequency dependences of the real and imaginary parts of the electrical impedance of a free resonator were measured and, using the Mason electromechanical circuit, the elastic module, viscosity coefficient, piezoelectric constant and dielectric constant of the resonator material (quartz) were determined. Then, the container was filled with the test sample of a liquid mixture so that the resonator was completely covered with liquid, and the measurement of the frequency dependences of the real and imaginary parts of the electrical impedance of the loaded resonator was repeated. The dependences of the frequency of parallel and series resonances, as well as the maximum values of the electrical impedance and admittance on the conductivity of liquids for various viscosity values, were plotted. It was shown that these dependences can be used to unambiguously determine the viscosity and conductivity of the test liquid. Next, by fitting the theoretical frequency dependences of the real and imaginary parts of the electrical impedance of the resonator loaded with the liquid under study to the experimental dependences, the elastic module of the liquid and its dielectric constant were determined.

Heuristic Algorithms for Power Quality Analysis in IEEE-33 &amp; IEEE-57 Bus Systems Using Fact Devices and Tracking

DGs have become increasingly important to the grid in connection with renewable energy systems as fossil fuels run out and pollution is on the rise. The integration of renewable energy sources into low-and medium-voltage distribution networks has opened up a new field of study. To ensure that distributed generation (DG) connections to the grid meet power quality standards, electronic power converters are a common component of renewable energy systems. In this case, major power quality issues will always occur if the inverters' switching frequencies are not appropriately location. On the other hand, power quality reductions can cause acute problems inpower networks, such as decreased performance, decreased useful life and efficiency of electrical and electronic equipment in the network, and series and parallel resonance caused by inductors and capacitors in some harmonics, which corrupts the distribution voltage. The present work focuses on quality assurance with compensation using nature inspired algorithms with DG placement after tracking. It compensates by adding fact devices. MBO, GWO and Cuckoo search algorithms are used in the present research and devices like DVR and Dstat.Com are added along with DG. The quality parameters are compared with the existing and in order to increase the robustness hybrid algorithms with any two are suggested.

Nonmonotone variable metric Barzilai-Borwein method for composite minimization problem

&lt;abstract&gt;&lt;p&gt;In this study, we develop a nonmonotone variable metric Barzilai-Borwein method for minimizing the sum of a smooth function and a convex, possibly nondifferentiable, function. At each step, the descent direction is obtained by taking the difference between the minimizer of the scaling proximal function and the current iteration point. An adaptive nonmonotone line search is proposed for determining the step length along this direction. We also show that the limit point of the iterates sequence is a stationary point. Numerical results with parallel magnetic resonance imaging, Poisson, and Cauchy noise deblurring demonstrate the effectiveness of the new algorithm.&lt;/p&gt;&lt;/abstract&gt;

Mode restrictions in the power supply system of industrial induction equipment

The article investigates the frequency features of the power supply of induction heaters designed for aluminum extrusion. Mode regulation is performed by local connection of capacitor banks with the creation of parallel resonance. The scheme of the power supply system is built on the basis of an adjustable frequency converter. To study the induction complex, a mathematical model was created in the frequency and time domains. The calculation showed the possibility of a resonant mode with a deterioration in the frequency regulation of currents with an unsuccessful choice of design. In the course of modeling using a modified nodal analysis, a set of parameters that create a resonance is considered. The frequency characteristics and vector diagrams of the induction device are obtained, which reveal the unfavorable mode. Based on the results of the study, recommendations are proposed for correcting the algorithms for controlling the inverter of the power supply system and overcoming the limitations.

Исследование резонаторов с продольным и поперечным электрическим полем с различными поперечными размерами

The influence of the diameter of a disk resonator with a radial electric field made on the basis of PZT-19 piezoceramics and the shear dimensions of a resonator with a lateral electric field (LFE) based on PZTNV-1 piezoceramics on their main characteristics, such as the frequencies of parallel and serial resonances and maximum values of the real parts of electrical impedance and admittance has been studied experimentally and theoretically.

Huanglian Jiedu Wan intervened with “Shi-Re Shanghuo” syndrome through regulating immune balance mediated by biomarker succinate

With increasing stress in daily life and work, subhealth conditions induced by “Shi-Re Shanghuo” syndrome was gradually universal. “Huanglian Jiedu Wan” (HLJDW) was the first new syndrome Chinese medicine approved for the treatment of “Shi-Re Shanghuo” with promising clinical efficacy. Preliminary small-sample clinical studies have identified some notable biomarkers (succinate, 4-hydroxynonenal, etc.). However, the correlation and underlying mechanism between these biomarkers of HLJDW intervention on “Shi-Re Shanghuo” syndrome remained ambiguous. Therefore, this study was designed as a randomized, double-blind, multicenter, placebo-controlled Phase II clinical trial, employing integrated analysis techniques such as non-targeted and targeted metabolomics, salivary microbiota, proteomics, parallel peaction monitoring, molecular docking and surface plasmon resonance (SPR). The results of the correlation analysis indicated that HLJDW could mediate the balance between inflammation and immunity through succinate produced via host and microbial source to intervene “Shi-Re Shanghuo” syndrome. Further through the HIF1α/MMP9 pathway, succinate regulated downstream arachidonic acid metabolism, particularly the lipid peroxidation product 4-hydroxynonenal. Finally, an animal model of recurrent oral ulcers induced by “Shi-Re Shang Huo” was established and HLJDW was used for intervention, key essential indicators (succinate, glutamine, 4-hydroxynonenal, arachidonic acid metabolism) essential in the potential pathway HIF1α/MMP9 discovered in clinical practice were validated. The results were found to be consistent with our clinical findings. Taken together, succinate was observed as an important signal that triggered immune responses, which might serve as a key regulatory metabolic switch or marker of “Shi-Re Shanghuo” syndrome treated with HLJDW.

Detection of single line to ground fault and self-extinguishing by using a variable and a fixedable inductance in distribution grid in power

This paper tackled the method for determining the number of Peterson coil which is can compensate with the capacitance because it is important in determining the state of parallel resonance, which in turn control the ground fault current and make the approximate value of the current equal to the current in the sound phases. In this way, we can protect the electrical devices and equipment from being damaged by residual current resulting from the arc due to ground fault, which increases the temperature of conductors which are to a breakdown of insulators and damaging them. Ground fault current equals three times the actual current, and its effect depends on two types of variables which are the first: the number of Peterson coils (which specify the inductance value and compensated) and second: the period time of extinguishing electric are in the ground fault. we obtain, by experimental in the lab where it using the servo motor to control the number of Peterson coils which in turn specify the variable and invariable inductance. We have obtained optimal results for the value of ground-fault current, detect the ground fault and treat it without effect of network load and without power cut off for consumer.