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1、Principle of Sensors传感器原理传感器技术基础Fundamentals of Sensor Technology 2.2.2、传感器的动态特性Dynamic characteristics of sensors Definition:Definition:The response characteristic of the response sensor to the time-varying input when the input changes rapidly with time.定义：定义：当输入量随时间较快地变化时，反应传感器对随时间变化的输入量的响应特性。传感器的
2、动态特性 传感器的动态特性 Dynamic characteristics of sensors Dynamic characteristics of sensors 多数传感器输入信号是随时间变化的，只是变化的快慢不同而已。缓慢变化的信号容易跟踪，变化较快的信号跟踪性能会下降。(Most sensor input signals change with time,but the speed of change is different.Slowly changing signals are easy to track,while fast changing signals will degr
3、ade their tracking performance.)一个动态性能好的传感器输入与输出应具有相同的时间函数，但除理想状态外，输出信号一定不会与输入信号有相同时间函数。(The input and output of a sensor with good dynamic performance should have the same time function,but the output signal must not have the same time function as the input signal except for the ideal state.)这种输入输出
4、之间的差异就是 动态误差 动态误差。(This difference between input and output is the dynamic error dynamic error.)传感器的动态特性 传感器的动态特性 Dynamic characteristics of sensors Dynamic characteristics of sensors 动态测温的几种情况：动态测温的几种情况：1、被测温度随时间快速变化；2、传感器突然插入被测介质中Several situations of dynamic temperature measurement:Several situat
5、ions of dynamic temperature measurement:1、The measured temperature changes rapidly with time;2、The sensor is suddenly inserted into the measured medium传感器突然插入被测介质中，设环境温度为T0，水槽中水的温度为T,而且 T T0；传感器在t0时刻突然插入被测介质中；理想情况测试曲线是阶跃变化的，实际温度传感器输出值是缓慢变化，存在一个过渡过程，这一过程与阶跃特性的误差就是动态误差。The sensor is suddenly inserted
6、into the measured medium Let the ambient temperature be T0,the temperature of water in the sink be T,and T T0;The sensor is suddenly inserted into the measured medium at T0 time;The test curve changes step by step ideally The output value of the actual temperature sensor changes slowly,and there is
7、a transition process.The error between this process and the step characteristic is the dynamic error.瞬态误差 瞬态误差 Transient error Transient error 稳态误差 稳态误差 Steady-state error Steady-state error 动态特性的研究主要包括两个部分：(The study of dynamic characteristics mainly includes two parts)：常用输入信号（Common input signals）
8、：微分方程 微分方程Differential equations Differential equations正弦周期信号和阶跃信号 正弦周期信号和阶跃信号Sinusoidal periodic signal and step signal Sinusoidal periodic signal and step signal 定义：定义：将各种频率不同而幅值相等的正弦信号输入传感器，其输出正弦信号的幅值、相位与频率之间的关系。Definition:Definition:Input sinusoidal signals with different frequencies and equal a
9、mplitudes into the sensor,and the relationship between the amplitude,phase and frequency of the output sinusoidal signals其表达式为：其表达式为：Its expression is:Its expression is:频率响应特性 频率响应特性 Frequency response characteristics Frequency response characteristics 为一复数，它可用代数形式及指数形式表示，即is a complex number,which
10、can be expressed in algebraic form and exponential form,namely 式中 分别为 的实部和虚部；分别为 的幅值和相角；Where is the real part and the imaginary part of respectively;is the amplitude and phase angle of,respectively;频率响应特性 频率响应特性 Frequency response characteristics Frequency response characteristics 幅频特性 幅频特性Amplitud
11、e-frequency characteristics Amplitude-frequency characteristics 相频特性 相频特性Phase frequency characteristic Phase frequency characteristicK 值表示了输出量幅值与输入量幅值之比，即 动态灵敏度 动态灵敏度，K 值是 的函数，称为 幅频特性 幅频特性，以K()表示。K value represents the ratio of output amplitude to input amplitude,that is dynamic dynamic sensitivity sensitivity.K value is a function of,which is called amplitude-frequency amplitude-frequency characteristic characteristic,is expressed by K().