采用热线法的高温粉体材料导热系数自动测试仪

Automatic Test Instrument for Measuring Thermal Conductivity of High Temprature Powder Material With Heat Wire Method

利用matlab对系统进行辨识、建模和降维后得到电阻炉的模型,然后依据该模型进行仿真寻优确定采用单片机模糊PID控制程序控制电阻炉的温度,进而使系统快速升温后保持所需初始恒温;在此初始恒温基础上利用热线通以恒流产生一个阶跃温度激励信号,系统自动采集该阶跃响应信号,并求取导热系数;采用模糊PID控制算法,缩短了测试周期,提高导热仪的测试效率,由于选择虚拟仪器平台,提高了测量处理的自动化和智能化程度;经试验证明,应用此测试仪可较大提高高温粉状材料的导热系数的测试精度与效率。

The author will apply Matlab to the system identification,dimension reduction and modeling cf resistance furnace model, then using SCM fuzzy Pid algorithms to control the temperature of furnace based on the model simulation, then rapid wanning, make sisterm to maintain constant temperature. Produce a step-temperature incentive signal in this initial temperature. The collection system automatically step response signals, and to strike a thermal conductivity. Due to fuzzy Pid algorithms, the test cycle will be shorten and the thermal efficiency of the testing instrument will be improved. As the choice of virtual instrument platform, the measurement automation and intelligence will be improved. The results of the tests show that the accuracy and efficiency of tests for high-temperature thermal conductivity can be improved.