风扇性能测试系统设计论文.doc

题 目 风扇性能测试检测系统设计 学 院 工业制造学院 专 业 测控技术与仪器 2013年 6 月 4 日风扇性能测试检测系统设计 专 业：测控技术与仪器 摘要：介绍风扇性能测试检测系统设计方案，对其软硬件的实现方法进行了介绍，该系统在实际工程应用中，具有较好的稳定性和精度。电机扇热风扇转速是电动机重要的基本状态参数，在很多运动系统的测控中，都需要对风扇转速进行测量，测量的精度直接决定测试系统的可行性，只有转速的高精度检测才能得到准确的风扇性能指数。目前工业中测量转速的方式主要有两种。一种是将转速转化为模拟信号，对模拟信号进行测量。如测速发电机是将转速直接转换为电压信号，然后测量其电压。这种方法的缺点是被测信号易受电磁干扰和温度变化的影响。另一种是将转速信号转化为脉冲信号，然后用数字系统内部的时钟来对脉冲信号的频率进行测量。这种方法的优点在于抗干扰能力强、不受温度变化影响、稳定性好。工业现场往往存在许多的干扰因素，因此工业测控系统中普遍采用数字式转速测量方法。目前plc因其高可靠性已经成为工业控制的一个重要设备。采用plc测量风扇和电机转速可以保证测量的稳定性和高精度。 关键词：PLC；转速测量；稳定性；高精度 The Design of Fan Performance Testing Detection System Specialty：easurement and Control Technology and Instrumentation Student Number： Student： Supervisor： Fan performance testing detection system design scheme, the hardware and software implementation method are introduced, the system in practical engineering applications, has a good stability and accuracy. Motor heat fan fan speed is an important basic state of motor parameters, in a lot of movement system of measurement and control, need for fan speed measurement, the accuracy of measurement directly decide the feasibility of the test system, can only get the exact fan rotational speed high precision detection performance index. Measuring speed in the industry there are two main ways: one is the rotating speed is converted into analog signals, the analog signal is measured. Such as tachogenerator is speed directly converted to voltage signal, and then measuring the voltage. The disadvantage to this approach is the measured signal is susceptible to electromagnetic interference and the impact of temperature change; Another kind is the rotational speed signal into pulse signal, and then use digital system internal clock to measure the frequency of pulse signal. The advantage of this approach lies in the anti-interference ability is strong, is not affected by changes in