摘要: |
为满足液氮直接蒸发制冷系统大温区范围内的高精度温度控制需求,本文提出一种应用于该类型系统控制需求的模糊PID控制策略,并建立了液氮直接蒸发制冷系统的一维动态分布参数模型,分别进行了﹣50、﹣80、﹣140 ℃等不同目标温度工况下的数值模拟与实验,结果表明:模拟与实验结果最大相对误差为7.8%,提出的模糊PID控制策略取得了较好的控制效果,在﹣50、﹣80、﹣14 ℃目标温度下,其温度波动范围分别为±0.5、±1.0、±2.0 ℃,实现了较宽低温区的高精度控温。 |
关键词: 直接蒸发 超低温 温度控制 模糊PID 数值模拟 |
DOI: |
投稿时间:2018-11-22 修订日期:2019-01-17
|
基金项目: |
|
Numerical Simulation and Experimental Study of Fuzzy-PID Control Method for Liquid Nitrogen Direct Evaporation Refrigeration System |
Hong Xing,Wu Jingyi,Wang Shanshan |
(Institute of Refrigeration and Cryogenics, Shanghai Jiao Tong University;Shanghai Institute of Spacecraft Equipment) |
Abstract: |
More presetting tasks for parameters in traditional PID controlling are required, thereby leading to complex processes, unsatisfied control effects, and poor adoption for system condition changing. In the liquid nitrogen direct evaporation refrigeration system, a fuzzy-PID control strategy was proposed based on the dynamic distributing parameter model of the systemto meet the requirements of the high-precision temperature controlling. Simulations were performed to analyze the effect of the control strategy in combination with the proposed model, indicating the sound adoption of the control strategy on the system. Experiments for the application of the control strategy were designed to investigate the control effect under the condition of target temperature ?50 ℃, ?80 ℃, or ?140 ℃. Experiment results showed that the maximum relative deviation of the simulation results on the experiment results reached 7.8%, and that the temperature fluctuations under different conditions are ±0.5 ℃, 1.0 ℃, or 2.0 ℃, which increased as the target temperature decreased. |
Key words: direct evaporation ultra-low temperature temperature control fuzzy PID numerical simulation |