Effect Of Higher Harmonics Research Articles

The effect of higher harmonics on gravitational wave dark sirens

ABSTRACT The gravitational wave (GW) signal from the merger of two black holes can serve as a standard sirens for cosmological inference. However, a degeneracy exists between the luminosity distance and the inclination angle between the binary system’s orbital angular momentum and the observer’s line of sight, limiting the precise measurement of the luminosity distance. In this study, we investigate how higher harmonics affect luminosity distance estimation for third-generation (3G) GW detectors in binary black hole mergers. Our findings demonstrate that considering higher harmonics significantly enhances distance inference results compared with using only the (2, 2) mode. This improved accuracy in distance estimates also strengthens constraints on host galaxies, enabling more precise measurements of the Hubble constant. These results highlight the significant influence of higher harmonics on the range estimation accuracy of 3G ground-based GW detectors.

Effect of higher harmonics on electric power quality in supply systems in mines

Effect of higher harmonics on electric power quality in supply systems in mines

A fully nonlinear BEM-beam coupled solver for fluid–structure interactions of flexible ships in waves

A fully nonlinear hydroelastic numerical method is proposed for the fluid–structure interactions of elastic ships. The boundary value problem is solved by the three-dimensional boundary element method. To simulate the instantaneous evolution on the free surface, an effective mesh optimization solution consisting of the local coordinate system and an elastic mesh technique has been developed. The mixed Eulerian–Lagrangian method is implemented to update the fully nonlinear free surface conditions in the local coordinate system. The hull structure is simplified as a non-uniform Timoshenko beam, and the modal superposition approach is adopted to analyse the symmetric responses in the head sea. Convergence of the model is evaluated for mesh resolutions and the time step size, and then comprehensive investigations of vertical motions as well as vertical bending moment are carried out for an advancing ship in a range of wave frequencies. The numerical solutions are compared with the experimental data and a satisfactory agreement is demonstrated. The distribution of high-order harmonics and whipping responses are predicted by the amplitude spectrum, in which the water entry and water exit are considered. The high-frequency vertical bending moments are investigated, in which the effects of higher harmonics and whipping responses are addressed.

New achievement of the global sheath-bulk model for the collisionless radio-frequency using in scale industries

Plasma processing is extensively utilized in enormous industries products like semiconductor devices, textile fabrics, modifying polymers, and seed treatments. One of the most significant enhancements to this technology is the low pressure of capacitively coupled plasma (CCPs). Contrary to other plasma processes like atmospheric pressure plasma jet, low-pressure plasma under vacuum is the best choice for scale industrial applications, including etching, semiconductor IC fabrication, and seed processing for agricultural use. This is due to its full soft control and complete ionization chamber. It is quite difficult to analyze the dynamics of the plasma sheath theory. Despite being among the most relevant models, the step approximation model does not fully account for all nonlinear dynamics, particularly high harmonic effects, the particle density singularity between the sheath and bulk regions, and the absence of an ambipolar field in the bulk zone. We provide a significant solution to this issue in this study. The numerical fluid model for collisionless self-consistency is solved. As a result, the sheath charge distribution V(Q), which is considered as the main factor of control all nonlinear dynamics of the sheath, is estimated. Strong agreement between experimental data from the Ziegler et al. [7] study and our cubic fitting formula for the V(Q) distribution. Additionally, by compared the results of step approximation with the non step model, theoretical advancements like handling the particle density singularity and the merging of the sheath-bulk zone are further illustrated. Moreover, the most simple but effective solution at a minimal computing cost, the global model, is solved. By applying accurate sheath charge distribution, which controls all nonlinear dynamics, the global model's accuracy is established. As a result, more nonlinear dynamics are achieved, including distributions of currents, densities, charges, and power. Finally, excellent calculations of average power and sheath distance in case of collisionless region are calculated. Our study can find a more accurate physical and engineering approach which may help in industry applications.

Harmonic-Balance-Based parameter estimation of nonlinear structures in the presence of Multi-Harmonic response and force

Testing nonlinear structures to characterise their internal nonlinear forces is challenging. Often nonlinear structures are excited by harmonic forces and yield a multi-harmonic response. In many systems, particularly ones with strong nonlinearities, the effect of higher harmonics in the force and responses cannot be ignored. Even if the intended excitation is a single frequency sinusoidal force, the interaction of the shaker and the nonlinear structure can lead to harmonics in the applied force. The effects of these higher harmonics of the input force on nonlinear model identification in structural dynamics are often neglected. The objective of this study is to introduce an identification method, motivated by the alternating frequency/time approach using harmonic balance (AFTHB), which is able to consider both multi-harmonic forces and multi-harmonic responses of the system. The proposed AFTHB method can include all significant harmonics by selecting an appropriate time step and sampling frequency to guarantee the accuracy of the results. An analytical harmonic-balance-based (AHB) approach is also considered for comparison. However, the inclusion of all significant harmonics of the response in the analytical expansion of the nonlinear functions is often cumbersome. Furthermore, the AFTHB method can easily cope with complex nonlinearities such as Coulomb friction and with multi-degree of freedom nonlinear systems. Including the effect of higher harmonics in the identification process reduces the approximation error due to truncation and very accurate approximation of the balanced equations of each harmonic is obtained. The proposed identification method requires prior knowledge or an appropriate estimation of the type of system nonlinearities. However, the method of model selection may be used for a set of candidate models, and avoiding a dictionary of arbitrary candidate basis functions significantly reduces the computational costs. This paper highlights the important features of the AFTHB method to ensure accurate estimation using four simulated and two experimental examples. The effects of the number of harmonics considered, the modelling error, measurement noise and the frequency range on the quality of the estimated model are demonstrated.

On the influence of electric power quality on the decimation of currents and voltages of utility frequency

The electric power industry cannot develop without analyzing the factors that affect the shape of currents and voltages when determining the parameters of the electric network mode in the context of the introduction of modern means of intellectualization into the structure of power supply systems. The share of equipment affecting the electric power quality reaches 90% in modern electrical networks. This leads to the appearance of noise in the network that reduces the quality of electrical energy, voltage distortion by higher harmonic components in particular, and affects the adequacy of the parameters of the electrical network adopted by automatic control devices. The article presents the results of digital signal processing containing distortions in the form of a harmonic component with a decrease in the sampling frequency. It is shown that a decrease in the sampling frequency does not exclude the effect of higher harmonics on the result of processing signals, including high-frequency distortions.

Effect of higher harmonics on electric power metering in a steel maker’s power networks

This paper describes the results of a study that looked at how harmonic voltage and current distortions affect the power metering equipment of an aluminium plant. Aluminium industry power supply circuits and power consumers have been analyzed. The main requirements are specified with regard to power monitoring systems designed for major consumers. It is shown that when calibrating commercial-type digital power meters no testing is required for the conditions of voltage or current distortions. At the same time, it is in these conditions that such devices are utilized at feeder points with non-linear loads. As a result of a series of laboratory studies, it was found that the number of the considered harmonics, their amplitude and the phase displacement angle at 50 Hz produce most effect on the active and reactive power monitoring error. The authors also analyzed mathematical models of the power and electric power meters in relation to the active and reactive power calculated in the presence of higher harmonics. It is shown that different mathematical equations can be used to calculate the reactive power using the current metering devices. The paper presents some measurement data on the electric power quality and the power consumption parameters from the compressor stations and the process water plants of an aluminium plant. The data show that the total voltage harmonics go beyond the allowable limit, and the distortions in that point are caused by variable frequency converters of the electrolysis facility. The measured parameters were used as the basis for estimating the error of the electric power meters for various mathematical models implemented in the meters. It was found that the discrepancy between the first harmonic method and the geometry method in the reactive power calculation can reach 6%.This research was funded by the Russian Science Foundation, Project No. 18-79-00127.

ВЛИЯНИЕ ВЫСШИХ ГАРМОНИК НА РАБОТУ ПРЕОБРАЗОВАТЕЛЯ ЧАСТОТЫ В УСЛОВИЯХ ПОДЗЕМНОГО РУДНИКА

Актуальность исследования обусловлена необходимостью выявления причин выхода из строя узлов и деталей преобразователя частоты, а также конденсатора фильтрокомпенсирующего устройства в системе электропривода скиповой подъемной установки. Выход из строя этого узла при отработке алгоритма защиты приводит к наложению предохранительного тормоза на подъемную машину, обладающую достаточно большой кинетической энергией, которая в свою очередь, рассеиваясь в узлах и деталях подъемной машины, приводит к сокращению их срока службы. Цель: определить степень влияния высших гармоник в системе электроснабжения подземного рудника на элементы преобразователя частоты системы электропривода скиповой подъемной установки и предложить методы по их снижению. Объекты: преобразователь частоты, система электропривода подъемной установки, система электроснабжения подземного рудника, другие технологические установки и их системы электропривода, влияющие на генерацию высших гармоник. Методы: инструментальный контроль показателей качества электрической энергии в соответствии с требованиями ГОСТ 32144-2013; математическая обработка и анализ полученных результатов при помощи программного обеспечения MathCAD; компьютерное моделирование режимов работы системы электропривода в среде MatLab. Результаты. Дана характеристика скиповой подъемной машины слепого скипового ствола и её системы электропривода. Проанализированы результаты обследования системы электропривода, полученные как до, так и после ввода установки в промышленную эксплуатацию. Исследованы причины выхода из строя фильтрокомпенсирующего устройства, а также проанализированы причины отказов в работе преобразователя частоты. Сделаны выводы о влиянии высших гармоник на работу преобразователя частоты в условиях подземного рудника. Предложены меры защиты электроустановок от высших гармоник и методы по их снижению.

HIGH CURRENT HARMONICS INFLUENCE ON THE CHOICE OF CONDUCTORS OF CRANE POWER SUPPLY SYSTEMS

Purpose. To study the effect of high current harmonics on the power and voltage losses in the conductive lines of the crane power supply systems and the development of an account method for this influence in practical calculations. Methodology. For research analytical methods and methods of simulation are used. Results. Analytical calculations have been performed for power losses and voltage losses for the conductors of crane power supply systems in the conditions of high harmonic generation for frequency-controlled drives. Originality. For the first time, the authors have obtained the analytical expressions and graphical dependencies in relative units for practical calculations that allow determining the effect of high harmonics to the values of power losses and voltage losses for crane supply systems, while the parameters of steel conductors are nonlinear for load current and frequency. We have established that the values of power losses and voltage losses increase for crane power supply systems. It is shown that the power losses lead to a decrease the efficiency of crane supply systems up to 7 %, which must be taken into account when choosing electric drive systems and its payback period. Practical value. The obtained theoretical expressions can be used for calculations, design, optimization of crane power supply systems in terms of high harmonic generation.

Effect of Higher Harmonics on the Accurate Calculation of Dynamic Phase-Locked-Loop Characteristics Using the Quasi-Harmonic Method

Abstract—The effect of higher harmonics on the accurate calculation of the dynamic characteristics of piecewise-linear phase-locked-loop frequency control using the quasi-harmonic method has been demonstrated at exactly known values of the lock-in range and the frequency of rotational motions.

Effect of higher harmonics in the area-ratio pulsed neutron source technique

The area-ratio pulsed neutron source technique, which can yield a subcriticality in dollar units, is given by Ap/Ad, the area ratio of the prompt neutron component to the delayed neutron component. In this paper, both components are reconstructed by the summation of the spatial harmonics that are obtained by solving the α–mode eigenvalue equations based on the neutron transport and diffusion theories. Monte Carlo simulations for the area-ratio method in a one-dimensional slab are performed. The reconstructed prompt and delayed components agree well with the simulation results. The areas Ap and Ad contain a higher harmonic effect, and the ratio Ap/Ad differs from the true subcriticality. The effect of the higher harmonics in Ap can be reduced by the extrapolated area-ratio method if the earlier period after the pulse generation is successfully excluded from the fitting period. However, there is no way to remove the effect of the higher harmonics from the delayed neutron component, but it alleviates itself because it is given by the subtraction of the prompt component from the total (delayed and prompt) component. The subcriticality in dollar units adjusted by the extrapolated area-ratio method is considerably improved compared with the unadjusted Ap/Ad. The improvement is remarkable for a near-critical system in which the denominator Ad is relatively large, and the effect of the higher harmonics in Ad is minor.

Energy harvesting from a piezoelectric slipper during walking

In this article, we study energy harvesting during human walking from a slipper that hosts a piezoelectric energy transducer. Specifically, we demonstrate the feasibility of energy harvesting when a human wearing a slipper without a heel counter walks on a treadmill. In contrast to other work, we focus on the bending of the slipper instead of the heel strike and foot pressure as an energy source. We analyze the deflection and electrical behavior of the slipper through video analysis and voltage output measurement, respectively. We observe the oscillation of the slipper after its toe-off and the effect of high harmonics on the slipper bending. Additionally, we predict the harvested power delivery to load resistances from the piezoelectric slipper using a model and compare it with the experimental results. We find that the harvested power increases and optimal load resistance decreases with walking speed.

Three-dimensional measurement of object surface by using ellipse binary defocusing projection

BackgroundThe accuracy of three-dimensional measurement of object surface is always affected by the nonlinear gamma of the projector. The defocusing binary projection can overcome the nonlinear gamma distortion of the projector and reduce the effect of high harmonics without gamma calibration. Although researches have already reduced the errors to get a clear sinusoidal curve, there still leave room for improvement, especially when wide stripes are applied during the measurement.MethodsThis paper presents a kind of ellipse binary pattern. By analyzing the property and spectrum, the binary pattern can produce high quality sinusoidal curve and produce smaller errors. It has a better effect to use an ellipse pattern to overcome the nonlinear gamma distortion of the projector and it is suit to be used as wide stripes.ResultsSimulation and comparison experiments plus three-step phase shifted method are conducted to verify feasibility and accuracy of this binary pattern. The experimental results have indicated that this binary pattern can increase the accuracy of 3D measurement and reduce phase errors caused by the nonlinear gamma of the projector. The defocusing ellipse pattern is superior to traditional methods. In addition, the defocusing binary stripe is robust and suit to measure object with large period.ConclusionsIn this paper, an binary ellipse pattern is proposed for high-accuracy 3D measurement profilometry. It is easy to generate high-quality sinusoidal fringe pattern. Experiment results have demonstrated the feasibility and accuracy of the improved binary pattern besides it proved that the period of fringe pattern has little impact on the accuracy of measurement.

Compensation of the reactive power in the presence of higher voltage harmonics at coke plants

The capacitive compensation of reactive power in the presence of harmonic distortion in the supply voltage is considered. Such distortion may be introduced both by factors in the external grid and by factors within the enterprise. That must be taken into account in selecting systems for reducing the effect of higher harmonics on compensating capacitor banks and improving the power quality at coke plants.

Prediction of the Voltage Quality in an Overhead Transmission Line with Distributed Parameters

The present work is devoted to investigation of an electrical transmission line with allowance for distributed parameters. From the results of voltage measurements at terminals of an actual transmission line, effective values of the voltage are calculated for every line section. Special attention is given to higher harmonics and asymmetry. Spectral composition of the voltage is presented and changes in values of harmonic components are analyzed. The effect of higher harmonics on the equipment operation is analyzed.

Harmonic Generation of Externally Applied Signal in a Biased Photoconductive Terahertz-Wave Emitter

A generation effect of higher harmonics for an externally applied signal in a photoconductive (PC) terahertz (THz)-wave emitter has been found. This effect is applicable to accurately measuring for frequencies of THz waves. This paper describes reasons why higher harmonics are generated in a PC device. The dependence of the photoconductance on the applied voltage in the PC device consists of a flat range and a negative slant range, and one sharply bending point is then formed at the boundary between the flat and slant ranges. When the PC device is irradiated by two laser beams with slightly different optical frequencies, the photoconductance is strongly modulated at the optical beat frequency in the THz region by photomixing the two laser beams. As a result, three bending points are formed in the average photoconductance (introduced as the average of the temporal photoconductance varying at the THz frequency). The slants comprised of the three bending points are different from each other. When the variation range of the applied voltage driven by the signal input on the biased voltage covers the voltage of one of the bending points, the photoconductance (or the average photoconductance in optical beating) varies along the different two slopes, the resultant temporal photocurrent is largely distorted, and then the harmonics of the signal input are generated in the photocurrent. The following features are clarified: (1) the harmonics of the signal input are generated by appropriately adjusting the bias voltage and the amplitude of the signal input, regardless of the presence/absence of optical beating; (2) the efficiency of the harmonic generation is about 10-4-10-5; and (3) the harmonics over 35th order with almost flat amplitudes (-3.8dB/octave) are generated.

多段歯車系の歯打ち現象における駆動トルクの高次成分の影響(機械力学,計測,自動制御)

多段歯車系の歯打ち現象における駆動トルクの高次成分の影響(機械力学,計測,自動制御)

Bounding the mass of the graviton with gravitational waves: effect of higher harmonics in gravitational waveform templates

Observations by laser interferometric detectors of gravitational waves from inspiraling compact binary systems can be used to search for a dependence of the waves' propagation speed on wavelength, and thereby to bound the mass or Compton wavelength of a putative graviton. We study the effect of including higher harmonics, as well as their post-Newtonian amplitude corrections, in the template gravitational waveforms employed in the process of parameter estimation using matched filtering. We consider the bounds that could be achieved using advanced LIGO, a proposed third generation instrument called an Einstein telescope and the proposed space interferometer LISA. We find that in all cases, the bounds on the graviton Compton wavelength are improved by almost an order of magnitude for higher masses when amplitude corrections are included.

241 多段歯車系の歯打ち現象における駆動トルクの高次成分の影響

241 多段歯車系の歯打ち現象における駆動トルクの高次成分の影響

Band structure of a parallel-plate waveguide filter having phase-shifted square-wave corrugations

In this paper, we study the effect of harmonics of phase-shifted square-wave corrugations on the different stopbands of a corrugated parallel-plate waveguide supporting TM waves. The stopbands are characterized by simultaneous occurrence of first-order and higher-order Bragg interactions. Coupled mode equations of two or four modes are derived via the method of multiple scales. Above cutoff of a higher-order mode, it is found that three resonance conditions must be satisfied: a first-order Bragg condition for the higher-order mode and a higher-order Bragg condition for the dominant TM10 mode, and a third condition coupling the two modes. A design of a multiple stopband filter for interference suppression in UWB applications is given showing all stopbands above cutoff of the TM10 and higher-order modes up to TM50 by including effects of higher harmonics of the structure. The bandwidth of each stopband is controllable by varying the phase shift between corrugations on the two walls of the waveguide. The fundamental matrix method is used to solve the filtering problem numerically.