Based On Fuzzy-pid Complex Temperature Control System Of Indium Point Blackbody Source Development

With the development of the level of radialization measurement (from 10-2 to 10-5), radialization metrology becomes the base of luminosity metrology and radialization thermometric scale. full irradiance benchmark of 500K-1000K is the base of radiology. As the national norm, it has been widely used in measuring infrared detector and blackbody radiation both in military and civil field, transmitting full Irradiance. The improvement and modernization of the norm devices will promote the modernization of radialization thermometric scale. As a result, we developed the In-freezing point blackbody radiation, extended thermometric range on the basis of tradition, improved our national system of full irradiance traceability, reached the goal of benchmark replicable and expand the transfered range.According to the requirement of subject, this paper designed and planed the whole system from the technologic reality and theory base. In development,we used the high purity In of 99.9999%.According cavity theory,we increased the area of radiant cavity, improved the uniformity of temperature in cavity and materials emissivity. Used the Nickel resistance wire cautery with the 0.5mm diameter, We can calculate the density of resistance wire and the energy according to the Joule - Lenz's Law. It has not a good effect by used the traditional PID control or Fuzzy control on the nonlinear long time-delay and time-varying object such as electric furnace. We used the combinated method both traditional PID control and Fuzzy control. We called it Fuzzy-PID control.It has many advantages such as the strong robustness,the fast response and the small overshot in Fuzzy control and the dynamic tracing steady-state accuracy in PID control.According to the control characteristics of Fuzzy and PID control, we used Fuzzy-PID control.It is used Fuzzy control in the dynamic process and turns to Fuzzy-PID control automatically in the steady process. It works automatically according to the setted deviation range. And it has the advantages of fast response in dynamic process and the good stability through the tiny control of PID. It's important to set the parameters of PID. It's trouble to set the parameters of PID and can't satisfy the require of different daviations and daviations rate if used the stationary PID control. And the robustness will be decrease.In measurement,we use the Platinum resistance thermometer with good stability,wide range and linear。And designed the circuit,got the results with high-precision and stability.According to the actual conditions, we made the correspond design. And we arrange the whole finished system in experiment field, analyze the characteris of vertical geothermal field, repeatability, etc so as to accord with the requirement of experiment. Evaluate the uncertainty of blackbody radiation, and the result corresponds the designed request.