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1.
介绍了霍尔传感器的原理以及工程应用中的霍尔传感器种类 ,举例说明了开关型霍尔传感器在重力加速度测量实验中的应用 ,同时给出了具体的应用电路  相似文献   

2.
在不同环境温度下,对霍尔位移传感器的静态特性进行了测试.结果表明,随着环境温度的变化,霍尔传感器的静态特性差异明显,从理论上分析了产生差异的原因.并对其应用实例进行了说明.  相似文献   

3.
高性能石墨烯霍尔传感器   总被引:1,自引:0,他引:1       下载免费PDF全文
黄乐  张志勇  彭练矛 《物理学报》2017,66(21):218501-218501
本文回顾了石墨烯霍尔传感器的相关研究工作.通过改善石墨烯生长转移和霍尔元件的微加工工艺,石墨烯霍尔元件和霍尔集成电路都展示出超越传统霍尔传感器的优异性能.石墨烯霍尔元件的灵敏度、分辨率、线性度和温度稳定性等重要指标都优于传统商用霍尔元件.通过开发一套钝化工艺,霍尔元件的稳定性有了明显提升.结合石墨烯材料的特点,展示了石墨烯在柔性磁传感和多功能传感领域的新颖应用.此外,成功实现了石墨烯/硅互补型金属-氧化物-半导体(CMOS)混合霍尔集成电路,并进行了应用展示.通过发展一套低温加工工艺(不超过180℃),将石墨烯霍尔元件制备在硅基CMOS芯片的钝化层上,从而与硅基CMOS电路实现了单片集成.本文的研究结果表明石墨烯在霍尔磁探测方向拥有重大的性能优势,在产业化应用中有巨大发展潜力.  相似文献   

4.
为精确测量伺服动力装置变量柱塞泵的转速,为其设计了一种小型化、高灵敏、抗干扰、高可靠、宽温域的霍尔型转速传感器。针对电感式转速传感器对较低转速测量不灵敏、易受磁场干扰等缺点,提出了一种霍尔型转速传感器的设计方法:利用霍尔电路对磁场信号反应灵敏的特性,另外在转速变换电路中配合以较高的阈值电压,使其具有灵敏度高和抗干扰能力强的特点;并结合整体任务要求,对其进行了小型化设计、宽温域材料选用及元器件的降额设计等措施。经试验验证,霍尔型转速传感器可以精确测量电机全量程(从低到高)的转速,灵敏度不随转速的变化而变化,且不受外界磁场的干扰,参数性能满足整体要求,具有广泛的应用前景。  相似文献   

5.
实验探究并验证了新型霍尔传感器在高精度直流隔离传送与检测中的应用,实验发现在直流隔离传送与检测中,霍尔传感器相比于其他传感器或互感器,具有传感精度高、非线性好等突出优点,能够满足高精度隔离传送与检测的要求.实验除具有实际应用价值外,还适合在高校物理基础试验中开设相关课程.  相似文献   

6.
通过自制的位移传感器演示装置可以对霍尔磁阻效应、 一种小位移测量传感器原理和方法进行演示和 探究. 在课堂教学、 课程设计等场合,直观显示霍尔元件的各种效应和技术应用, 有着良好的教学效果  相似文献   

7.
霍尔传感器作为一种半导体器件,其灵敏度随着温度变化而产生漂移的特性,限制了其在高精度磁场测量场合的应用。传统的温度补偿方法虽然对温度变化的一次项进行了完全补偿,但是却引入了温度变化二次项的误差。因此,对于温度变化显著的高精度测量场合,传统温度补偿法将不再适用。设计了一种闭环反馈电路,通过温度传感器采集温度信号,与信号处理电路的最终输出信号进行运算后送回信号处理电路的输入端进行补偿,而并不是简单地将温度信号与霍尔信号的输入信号进行相加后送入信号处理电路。仿真分析结果表明,通过调节补偿电路的反馈比例系数与霍尔芯片温度漂移系数,可以完全补偿霍尔芯片的灵敏度漂移。因此,这种闭环补偿方法可以不引入与温度变化二次项有关的误差,消除因温度变化产生的漂移,不仅适用于霍尔传感器,也适用于其他会随着温度漂移的传感器。  相似文献   

8.
霍尔效应在直流电压隔离传送中的应用   总被引:2,自引:1,他引:1  
瞿华富  唐涛 《物理实验》2007,27(2):16-18
应用基于霍尔效应的磁平衡原理设计了直流电压高精度隔离传送传感器,并与光耦传感器进行了比较,结果表明:在温度变化的环境中,该传感器隔离传送直流电压的精度优于光耦传感器28倍.  相似文献   

9.
本文介绍了半导体材料的霍尔效应及磁阻效应,讨论了霍尔磁阻元件的特性,提出位移传感器的工作原理、结构设计,并详细说明安装和调试过程.演示装置结构简单、物理概念清晰、易于操作.它将磁场的变化无接触转化为材料的电阻变化,从而把与磁场变化相联的位移形式转化为电信号输出,形成位移传感器.由实验数据和图示曲线表明:测量桥路输出电压随磁钢和霍尔片之间的距离变化而变化;另外,测量桥路的测量灵敏度随工作电流IC增加而提高.通过本装置可以对霍尔磁阻效应、一种小位移测量传感器原理和方法进行演示和探究.在课堂教学、课程设计等场合,直观显示霍尔元件的各种效应和技术应用,有着良好的教学效果.  相似文献   

10.
新型霍尔传感器的特性及在测量与控制中的应用   总被引:11,自引:2,他引:9  
张欣  陆申龙 《大学物理》2002,21(10):28-31
简述新型霍尔传感器的特性及在自动控制、信息处理和物理量测量中的应用。  相似文献   

11.
Iodine release in potassium iodide solution has been investigated under the irradiations of ultrasound and visible light respectively and simultaneously. We have observed that the amount of iodine liberated under the combined irradiation of ultrasound and visible light is larger than the sum of that under the respective irradiations of ultrasound and visible light, indicating a synergistic effect of ultrasound and visible light irradiations. Based on the investigation of the reaction kinetics of iodine liberated, we have ascribed the synergistic effect to the perfect stirring of the photochemical reactor induced by the applying simultaneous ultrasound. The ideal stirring can result in the homogenization of the primary light effect in the whole reaction medium, which induces the acceleration of the photochemical reaction. On behavior of our knowledge, there are few reports on the investigations of utilizing the combination of ultrasonic energy and light energy to accelerate the reaction yield and rate as well as the kinetics of the reaction.  相似文献   

12.
Fourier transform infrared spectroscopy (FTIR) was employed to study the human epidermis larynx carcinoma cell lines (Hep-2) which were irradiated by different doses of X-ray.The results show that (1) the irradiation of X-ray damages the structure of the CH3 groups of the thymine in DNA,which restrains the reproduction of Hep-2 cells effectively,(2) the 8 Gy dose of X-ray irradiation changes the framework and the relative contents of some proteins,lipids and the nucleic acid molecules intercellular in the greatest degree,and (3) the 8 Gy dose of X-ray irradiation is the best irradiation dose for lowering the degree of the cancerization of Hep-2 cells according to the criteria for the degree of the cancerization reported recently.Meanwhile,the apoptosis of these cells were detected by using flow cytometry (FCM) primarily.It shows that the apoptotic ratio of the Hep-2 cells depends on the irradiation dose to some extent,but is not linearly.And the apoptotic ratio of the 12 Gy dose group is the maximum (20.36%),but the apoptotic ratios of the 2 to 8 Gy dose groups change little.  相似文献   

13.
The electromagnetic ultrasound is used in the detection of interfaces of the adhesive multilayer structures to solve the unstable coupling problem in ultrasonic testing by traditional piezoelectric transducers. Based on the analysis of the transforming mechanism of electromag-netic ultrasound energy and the resultant dead zone from mutual inductance of the transducer, the wavelet filtering by soft-thresholding and adaptive noise canceling methods are used simul-taneously to the detected electromagnetic ultrasonic signals to overcome the drawbacks of the low signal to noise ratio (SNR) and the wide intrinsic dead zone of the transducer. Processed results in the interface detection of a three layered adhesive sample of steel and rubber materials demonstrate that the wavelet filtering enhances the SNR about 12dB while the adaptive noise canceling narrows the dead zone effectively.  相似文献   

14.
The formation of Saturn and its disk is simulated using a new N-body self-gravitational model. It is demonstrated that the formation of the disk and the planet is the result of gravitational contraction of a slowly rotated particle cloud that have a shape of slightly deformed sphere. The sphere was flattened by a coefficient of 0.8 along the axis of rotation. During the gravitational contraction, the major part of the cloud transformed into a planet and a minor part transformed into a disk. The thin structured disk is a result of the electromagnetic interaction in which the magnetic forces acting on charged particles of the cloud originate in the core of the planet. The simulation program gives such parameters of Saturn as the escape velocity of about 35 km/s at the surface, density, rotational velocities of the rings and temperature distribution.  相似文献   

15.
In high gain harmonic generation (HGHG) free electron laser (FEL), with the right choice of parameters of the modulator undulator, the dispersive section and the seed laser, one may make the spatial bunching of the electron beam density distribution correspond to one of the harmonic frequencies of the radiator radiation, instead of the fundamental frequency of the radiator radiation in conventional HGHG, thus the radiator undulator is in harmonic operation (HO) mode. In this paper, we investigate HO of HGHG FEL.Theoretical analyses with universal method are derived and numerical simulations in ultraviolet and deep ultraviolet spectral regions are given. It shows that the power of the 3rd harmonic radiation in the HO of HGHG may be as high as 18.5% of the fundamental power level. Thus HO of HGHG FEL may obtain short wavelength by using lower beam energy.  相似文献   

16.
In order to ease the pass-band response distortion of the matrix pre-filter,a simple approach for designing matrix spatial filter is proposed,which minimizes the sum of the k maximal distortion norm(k is the number of the constraint points)within the pass-band,while constraining the filter response within the stop-band.Considering the costly amount of calculation of the high-resolution methods,an algorithm with small amount of calculation based on matrix pre-filtering and subspace fitting using acoustic vector array(MF-VSSF)is proposed.Through joint processing of signal subspace of both pressure and particle velocity,the pre-filtering matrix and the signal subspace is decreased to M-dimensional(M is the number of array-element),hence reduces the time-consumption of the matrix pre-filter design and DOA searching.Simulation results show that,the method offers the same performance as MUSIC with pre-filtering,but has much lesser amount of calculation.Moreover,the designed prefilter can efficiently suppress the interference in the stop-band and improve the estimation and resolution performance of successive DOA estimators.  相似文献   

17.
The beam dynamic code PARMELA was used to simulate the transportation process of accelerating electrons in S-band SW linacs with different energies of 2.5, 6 and 20 MeV. The results indicated that in the ideal condition, the percentage of electron beam loss was 50% in accelerator tubes. Also we calculated the spectrum, the location and angular distribution of the lost electrons. Calculation performed by Monte Carlo code MCNP demonstrated that the radiation distribution of lost electrons was nearly uniform along the tube axis, the angular distributions of the radiation dose rates of the three tubes were similar, and the highest leaking dose was at the angle of 160° with respect to the axis. The lower the energy of the accelerator, the higher the radiation relative leakage. For the 2.5 MeV accelerator, the maximum dose rate reached 5% of the main dose and the one on the head of the electron gun was 1%, both of which did not meet the eligible protection requirement for accelerators. We adopted different shielding designs for different accelerators. The simulated result showed that the shielded radiation leaking dose rates fulfilled the requirement.  相似文献   

18.
In order to understand the viscoelasticity of material, this research has been conducted to study the propagation characteristics of viscoelastic Rayleigh wave theoretically. A model is presented for the pulsed laser generation of ultrasound on viscoelastic medium surface. Referred to the Kelvin model, the frequency equation and the normal displacement of viscoelastic Rayleigh wave were derived, the influence of the viscoelastic modulus on dispersion and attenuation was discussed. From the theoretical calculation, it is shown that the effect of viscoelasticity on the attenuation of Rayleigh wave is more than that on its dispersion. In the case of a weak viscosity, the attenuation of viscoelastic Rayleigh wave is directly proportional to viscosity modulus; the effect of shear viscosity on the attenuation is much more than that of bulk viscosity. The transient response of viscoelastic Rayleigh wave was also simulated using Laplace and Hankel inversion transform, which are showed in good agreement with the theoretic predictions. The model provides a useful tool for the determination of viscoelastic parameters of medium.  相似文献   

19.
Spectral characteristics of stochastic fields and their spatial derivatives in various planar structures composed by lossy materials described by realistic dielectric functions are numerically calculated based on solutions to the problems of multipolar electromagnetic fields in a plane layered geometry. A displacement of the maximum of the spectral power densities for spatial derivatives of fluctuating fields to the high-frequency domain, a resonant increase in the density of states of the fluctuating fields at the frequencies of interface excitations and interference modes for the radiative part of the spectra, the influence of geometry on the density of states, and other peculiarities are found by numerical calculations and graphically demonstrated. Interpretations of the above effects are provided.  相似文献   

20.
In a capillary discharge experiment for the neon-like argon lasing, we have proposed an experimental scheme to verify that the multi-spike of X-ray diode (XRD) signal is a multi-pulse laser or is a reflection of the laser pulse in the XRD.The ceramic capillary has an inner diameter of 3mm and a length of 200mm.At the gas pressure of 28Pa and discharge current of 27kA, stable lasing has been realized.The experimental results prove that the multi-spike of XRD signal is a reflection of the electromagnetic signal produced by the laser pulse in the XRD.The improved electrocircuit scheme of the XRD to minimize the reflection phenomena is also found.  相似文献   

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