【作者】 殷红彩；

【导师】 葛立峰；

【作者基本信息】 安徽大学 ， 检测技术与自动化装置， 2007， 硕士

【摘要】 压电加速度传感器是振动与冲击测量的核心部件，在现代工业和自动化生产过程中具有非常重要的作用，特别是在精度、长时间稳定性等方面具有独到之处。压电加速度传感器可以看作是能产生电荷的高内阻发电元件，其产生的电荷量很小，而一般的测量电路的输入阻抗较小，压电片上的电荷通过测量电路时会被输入电阻迅速泄漏而引入测量误差。因此压电加速度传感器要有与之配套的测量电路一起使用，否则其使用就要受到很大的限制。电荷放大器是目前最常用的压电加速度传感器的测量电路，它能得到与输入电荷成比例的电压输出，其特点之一就是传感器的灵敏度与电缆长度无关。本文提出了一种用集成芯片来取代大量分离元件的电荷放大器的设计方法，所设计的电荷放大器由电荷转换级、归一化放大级、高低通滤波级、输出级、稳压电源和过载指示级等六个部分组成。并在电荷转换部分的灵敏电容的切换和输出放大级的增益切换电路中提出一种程控方法解决的方案，并进行了详细的理论分析，从而解决了手动调节容易给系统带来误差和干扰的问题。同时本文对电路系统中存在的干扰信号及引入的误差作了细致的理论分析，并采取了相关的办法进行解决。最后，和标准的电荷放大器的性能进行对比，验证了本设计的可行性。作者完成的主要工作包括：(1)通过对压电加速度传感器的测量电路的各种实现方案的深入调研，提出了一种用集成芯片取代大量分离元件的电荷放大器的实现方案；(2)制作了完整的电路板；(3)在电荷转换部分的灵敏电容的切换和输出放大级的增益切换电路的实现上提出了程控的方案；(4)进行了实验验证，给出了实验结果；(5)在实验结果的基础上，结合电荷放大器原理对系统作了误差分析。更多还原

【Abstract】 Piezoelectric accelerometer is at the very core of the measurement in the vibration and strike, and it is very important in modern industry and automatic production. Especially in precision, long-time stability it has very fine quality. Piezoelectric accelerometer can be regarded as the component that can produce charge with the high impedance. But this charge amount is very small, and the input impedance of general measurement circuit is always small, the charge of the piezoelectricity slice would be leaked easily through this measurement circuit, and it can bring in inaccuracy of the measurement. So the piezoelectric accelerometer has been matched with its related measurement circuit, or else the wide application has been greatly restricted.At present, most popular measurement circuit used for piezoelectric accelerometer is charge amplifier. It can get a kind of voltage output which is proportional to the input charge. One of its characteristics is to make the sensitivity of the sensor have nothing to do with the length of the cable. A design of charge amplifier which used integrated chip replace a large number of leave components has been developed in the paper. It contains six parts of charge convert, normalization magnify, high and low pass filter, output amplifier stage, stabilized voltage power supply and overload indicator. In order to solve the problem of error and interfere to the system by manual regulation, a programme-controlled scheme in sensitivity throw-over of charge convert and gain throw-over of output amplifier has been proposed in this paper. The principle analysis of error and undesired signal has been done at great length, and relevant way to solve it has been adopted in the paper, too. Finally the system is contrasted with the standard charge amplifier, the experimental result indicated that it is feasible to original design.Main works of the author:(1) Has developed a design of charge amplifier which using a kind of integrated chip replace a large number of leave components, though all the realized proposal of measurement circuit for the piezoelectric accelerometer;(2) Has made the circuit board;(3) Has proposed a programme-controlled scheme in the sensitivity throw-over of charge convert and gain throw-over of output amplifier;(4) Has done the experiment, give the experimental result;(5) Has done the error analysis based on the experimental result and the principle of the charge amplifier.更多还原