1、 毕业论文 (设计 )外文资料翻译 学 院 ： 专 业： 电子信息工程 姓 名： 学 号： 07418502 外文出处： （用外文写） 附 件： 1、 外文资料翻译译文； 2、 外文原文。 指导教师评语： 该同学的外文资料翻译，紧扣论文主题，语句较通顺，翻译较准确。说明前期准备阶段的文献调研做了一定的工作，达到了预期的目的 。 签名： 2011 年 5 月 20 日 The piezoelectric acceleration sensor and its application Abstract: in recent years the piezoelectric acceleration
2、sensor got bigger development, this article expounds the piezoelectric acceleration sensor principle and constitute element, and the analysis of its frequency characteristics and sensitivity, exploring the error formation factors, summarizes its application in the field of engineering control. One,
3、the piezoelectric acceleration sensor principle The piezoelectric acceleration sensor and says piezoelectric accelerometer. It also belongs to the inertial sensor. It is the use of certain substances, such as quartz crystals piezoelectric effect, in the accelerometer, quality by vibration of piezoel
4、ectric element and in the force changed also. When measured vibration frequency is far lower than the natural frequency of the accelerometer, the change of force by using is proportional to the acceleration. Because of the piezoelectric sensor output signal is weak charge, and sensor itself has a gr
5、eat internal resistance, so little, the output energy behind the circuit to bring certain difficulties. Therefore, usually the sensor signal to lose to high input impedance of the preamplifier. After impedance transformation can be used in the future, amplification, detection circuit will signal los
6、s to indicating meter or recorder. Second, the piezoelectric acceleration sensor constitute elements (a) center installation compression type (b) ring shear (c) triangle shear Commonly used the piezoelectric accelerometer structure form shown in figure 13.18. S is spring, M is the mass, B is base, P
7、 is piezoelectric element, R is clamping ring. Figure 13.18 a is the central Ann loaded compressed type, piezoelectric element-quality piece of-spring system installed in the circular center struts, supports and base connection. This structure has high resonant frequency. However base B and the test
8、ing to like connection, if base B are the deformation will directly influence the vibration system output up. In addition, the test object and environment temperature change will affect piezoelectric element, and make preloaded force change, easy cause temperature drift. Figure 13.18 c to the triang
9、le shear form, by clamping ring piezoelectric element will be the clip in triangle center column in prison. Accelerometer feel axial vibration, bearing the piezoelectric element by shear stress. This structure deformation and temperature changes to the base have extremely good isolation effect, have
10、 higher resonance frequency and good linear. Figure 13.18 b ring, simple structure, shear can make it very small, high resonance frequency accelerometer, the ring of quality stuck to pack in the center of the ring on the pillar piezoelectric element. Due to the binder will increased with temperature
11、 become soft, so the highest working temperature is limited. Three, the piezoelectric acceleration sensor amplitude frequency characteristics The use of accelerometer ceiling depends on the amplitude frequency curve frequency resonant frequency map (figure 13.19). General small damping (z = 0.1) of
12、the accelerometer, upper limit for the resonant frequency if the frequency of a third, can guarantee amplitude error is less than 1 dB (12%)； If take for 1/5 of the resonant frequency are guaranteed amplitude error is less than 0.5 dB (6%), and phase shift less than 30. But the resonant frequency an
13、d accelerometer fixed condition, accelerometer related factory the amplitude frequency curve is given in the rigid connection get fixed. Of the actual use of the fixed method is often difficult to reach, and rigid connection resonance frequency and use frequency will cap fell. The accelerometer and specimen of fixed method is shown in figure 13.20.
