This paper studies the definition and calculation method of power grid strength in the environment of high-proportion nonsynchronous-machine sources, focusing on the effect of nonsynchronous-machine sources on voltage support strength and frequency s...
In a constantly and rapidly changing global environment, one of the main priority tasks for every country is preserving, maintaining, and operating an independent and individually robust and stable energy system. This paper aims at researching electr...
The beat signal obtained from frequency-modulated continuous-wave (FMCW) radar is a waveform that is corrupted by noise and requires filtering out interference components for frequency calibration. Traditional FFT methods are affected by the fence ef...
This paper proposes a multi-objective collaborative optimization method based on a two-layer optimization framework to address the problem of difficult coordinated optimization of multi-parameter coupling in the frequency regulation performance of he...
This work investigates the natural vibration characteristics of free-form shells when considering the influence of uncertainties, including initial geometric imperfection, shell thickness deviation, and elastic modulus deviation. Herein, free-form sh...
Recently, virtual synchronous generators (VSGS) are a hot topic in the area of microgrid control. However, the traditional fixed-parameter-based VSG control methods have an obvious disadvantage. Namely, if the damping value is set to be small, the am...
As research into data centers progresses, the importance of resonant switched-capacitor converters in power supply design becomes more evident. Practical applications reveal that the values of resonant capacitors and inductors may deviate from their...
The paper features the development of multi-dimensional mathematical models used for evaluating the impact of selected factors on the vibration generated by 6304ZZ type rolling ball bearings from three manufacturers in the aspect of the wear process....
Frequency estimation of a sinusoidal signal is a fundamental problem in signal processing for the Internet of Things. The frequency interpolation estimation algorithm based on the fast Fourier transform is susceptible to being disturbed by noise, whi...
This paper presents a new grid-forming strategy for hybrid AC/DC microgrids using bidirectional virtual inertia support designed to address weak grid conditions. The stability of hybrid AC/DC microgrids heavily relies on the AC mains frequency and th...
As the penetration rate of wind power systems is rising, which causes the overall system’s inertia to decline, the power system’s capacity to regulate frequency will be negatively affected. Therefore, this paper investigates the inertia c...
With the increasing penetration of renewable energy, frequency stability issues in new-type power systems have become increasingly prominent due to reduced system inertia and weakened primary frequency regulation capability. To address the insufficie...
A synthetic aperture radar (SAR) raw signal simulator is useful for supporting algorithm innovation, system scheme verification, etc. Trajectory deviation is a realistic factor that should be considered in a SAR raw signal simulator and is very impor...
In the applications of rail transit and electric vehicles, sensorless control of interior permanent magnet synchronous motor (IPMSM) usually uses high frequency (HF) signal injection in low speed or zero speed. Rotating HF signal injection based on t...
The utility factor (UF) of a plug-in hybrid electric vehicle (PHEV) refers to the ratio of miles traveled in electric mode to the total miles traveled. Standard UF curves provide a prediction of the expected achievable UF by a PHEV given its all-elec...
As a ranging sensor, a continuous transmission frequency modulation (CTFM) sonar with its ability for range finding and range profile formation works effectively under stationary conditions. When a relative velocity exists between the target and the...
The vibration problem influences the precision of the equipment. However, some vibration isolation systems (VISs) with the perfect theoretical and simulation results are still unable to suppress the vibration well, resulting in the damage during the...
In power systems, high renewable energy penetration generally results in conventional synchronous generators being displaced. Hence, the power system inertia reduces, thus causing a larger frequency deviation when an imbalance between load and genera...
In this study grape must fermentation is monitored using a self-actuating/self-sensing piezoelectric micro-electromechanical system (MEMS) resonator. The sensor element is excited in an advanced roof tile-shaped vibration mode, which ensures high Q-f...
Large photovoltaic stations, wind farms and high-voltage direct current (HVDC) transmission systems are being integrated into the grid, which is causing the stability of frequency and voltage of new power systems to decline, thereby imposing high req...
In this paper, the non-ideal factors, which include spatial noise and temporal noise, are analyzed and suppressed in the high-speed spike-based image sensor, which combines the high-speed scanning sequential format with the method that uses the inter...
The paper presents a novel linear, high-fidelity millimetre displacement-to-frequency transducer, based on the resistive conversion of displacement into a proportional voltage, and then frequency. The derivation of the nonlinearity, fidelity and sens...
The time maintenance accuracy of the navigation constellation determines the user positioning and timing performance. Especially in autonomous operation scenarios, the performance of navigation constellation maintenance time directly affects the dura...
Detection of the vibration trajectories of MEMS micromirrors is crucial for ensuring their application performance. This study investigates key factors influencing micromirror vibration trajectories. When actuated by a square-wave signal containing h...
This paper presents an investigation of the influence of higher-order harmonics on the frequency-response characteristics of a full-bridge series-resonant DC-DC converter. A Fourier series-based analytical method is developed to include these harmoni...
A high-efficiency frequency multiplier is presented in 65-nm CMOS with a core area of 0.06 mm2. A low-cost five-segment triangular-resistance phase interpolation scheme is proposed. By performing resistive interpolation on four-path orthogonal triang...
The dimensional and geometrical quality of additively manufactured parts must be increased to match industrial requirements before they can be incorporated to mass production. Such an objective has a great relevance in the case of features of linear...
With the high-proportion integration of renewable energy into the power grid, the fast-response capabilities of demand-side flexible resources (DSFRs), such as electric vehicles (EVs) and thermostatic loads, have become critical for frequency stabili...
This paper investigates harmonic compensation for an LCL-filtered cascaded H-bridge (CHB) STATCOM operating in medium-voltage distribution networks under grid-frequency deviations and nonlinear loads. A hybrid current control strategy is proposed by...
The Young’s modulus and internal friction are two important parameters of materials. Self-mixing interferometry (SMI) is an emerging non-destructive sensing method that has been employed for various applications because of its advantages of simple st...
This paper proposes a coordinated control scheme for wind turbine generators (WTGs) and energy storage in microgrids with high wind power penetration. The proposed scheme aimed to reduce the system frequency deviation caused by variations in wind pow...
Recently, high frequency bands (above 6 GHz) have attracted more attention for the next generation communication systems due to the limited frequency resources below 6 GHz. To reveal the influence of frequency on propagation channels, channel charact...
The frequency regulation problem of the power system under the scenario of a high proportion of new energy access has attracted attention. It has become an important technical means for new energy to reserve a certain amount to participate in system...
In this study, a dynamic equation for a micromechanical resonant accelerometer based on electrostatic stiffness is analyzed, and the parameters influencing sensitivity are obtained. The sensitivity can be increased by increasing the detection proof m...
As a system of ranging and positioning based on time transfer, the timekeeping ability of a navigation satellite constellation is a key factor for accurate positioning and timing services. As the timekeeping performances depend on the frequency stabi...
The high penetration of renewable energy brings significant power fluctuations and operational uncertainties to distribution networks. Traditional power allocation methods for hybrid energy storage systems (HESSs) exhibit strong parameter dependency,...
High penetration of converter-based wind generation reduces system inertia. It poses challenges to frequency stability in modern distribution networks, particularly in doubly fed induction generator (DFIG)-based wind-energy-conversion systems (WECSs)...
In this paper, the characterization and analysis of a silicon micromachined Quad Mass Gyroscope (QMG) in the rate mode of operation are presented. We report on trade-offs between full-scale, linearity, and noise characteristics of QMGs with different...
This paper presents a novel dual-band substrate integrated waveguide (SIW) sensor that is designed to measure the complex permittivities of liquids or solid powders at two industrial, scientific, and medical (ISM) frequencies simultaneously. Resonant...
The large-scale integration of renewable energy generation into the grid has led to increased frequency fluctuations in the power grid. Distributed energy storage systems, with their rapid response times, serve as a critical resource for primary freq...
Deception jamming of synthetic aperture radar (SAR) has attracted extensive attention due to its low power consumption and high fidelity advantages. However, existing SAR deception jamming algorithms assume that SAR operates on a linear trajectory. I...
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This study aimed to investigate prevalence and correlates of alcohol consumption frequency in a sample of Swiss conscripts (n=25,611) in order to identify factors that predispose for frequent consumption. A self-report of drinking frequencies, as wel...
The propulsion systems of hybrid electric ship output and load demand have substantial volatility and uncertainty, so a hierarchical collaborative control energy management scheme of the ship propulsion system is proposed in this paper. In a layer of...
The crosslinked polyethylene (XLPE) cable safety is affected by environmental factors and artificial defects during operation. This work proposes an improved locating method based on broadband impedance spectrum (BIS) to locate local defects in XLPE...
Interference recognition from time–frequency images requires lightweight models that can maintain recognition performance when signal parameters deviate from their nominal settings. We propose ASD-Net, a decreasing-group fully connected archite...
Building a mathematical model of uneven illumination and contrast is difficult, even impossible. This paper presents a novel image balancing method for a satellite image. The method adjusts the mean and standard deviation of a neighborhood at each pi...
Pre-defined motion command profiles enable precise positioning and dynamic control in mechanical and mechatronic systems, maximizing efficiency and reliability. Real-world applications introduce dynamic factors like mechanical compliance, friction, a...
We review recent experimental progress concerning the 87Sr optical lattice clock at the National Time Service Center in China. Hertz-level spectroscopy of the 87Sr clock transition for the optical lattice clock was performed, and closed-loop operatio...
Frequency tuning nonlinearities in semiconductor lasers constitute a critical factor that degrades measurement precision and spectral resolution in frequency-modulated continuous-wave (FMCW) LiDAR systems. This study systematically investigates the i...
In this study, frequency locking technology is investigated for high-stability microwave frequency standards based on diamond nitrogen-vacancy (NV) centers. Conventional locking methods typically utilize the side peaks induced via Zeeman splitting; h...
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