【作者】 刘长敏；

【导师】 陈照章； 徐晓斌；

【作者基本信息】 江苏大学 ， 控制理论与控制工程， 2006， 硕士

【摘要】 伴随着人类在低温生物学领域的探索过程，低温显微技术应运而生并得以不断的发展。人们可以借助这一技术观察到生物样品在冷冻和复温过程中的形态变化，以及溶液相变的过程，从而分析生物材料的相关特性，并以此为依据客观的解释实验结果、修正理论模型和制定合理的治疗或保存方法。 本文简要介绍了目前低温显微镜及温控智能算法的研究与发展，并在此基础上设计了一种以半导体制冷器为控温元件，采用分段式智能控制的微机温控显微系统，温控范围达到-10℃～+40℃，最大降温速率达到5℃／min，最大升温速率达到10℃／min，稳态精度达到±0.5℃。 本文所做主要工作如下： 1．结合使用需要，对温控显微系统的总体平台进行设计。确定系统核心采用PC机作为主控单元，利用数据采集卡采集温度信号，并对普通生物显微镜的改装进行了介绍。 2．设计并实现了系统的硬件部分。包括铂电阻传感器的选择，热电阻信号调理板以及H桥可逆驱动电路的设计。 3．设计并实现了系统软件的各模块。软件采用Visual Basic 6.0编写，具有友好的人机界面。实现了对硬件的接口编程，数据采样，数字滤波，数据处理和PWM波输出等功能。 4．由于半导体制冷器温控系统具有大惯性、纯滞后、结构参数时变的特点，难于建立其精确的数学模型。因此，结合系统对于降温速率控制及恒温控制的需要，本文设计了一种分段式两级控制器，第一级采用模糊控制，适应性强，不需要精确的数学模型，动态性能较好，第二级采用模糊自整定PID控制，具有较高的稳态精度，鲁棒性好，可靠性高。 通过对试样的实验结果可以看出，本文所提出的分段式智能控制器对大惯性、具有纯滞后环节对象的控制是很有效的，能很好的完成速率控制及恒温控制的设计要求。并具有较好的可移植性，可用于具有类似特性的被控对象。更多还原

【Abstract】 Cryomicroscope is an important tool in the research of low temperature biology and medicine. With the help of cryomicroscope, the dynamic, micron-scale, visual investigation of freezing and thawing processes in living tissues and individual cells can be carried out.In this essay, the historical development and current status of cryomicroscope and the tempareture control algorithms are briefly introduced. A microscope system with computer-controlled temperature based on semiconduct cooler and a piecewise fuzzy intergal control algorithms are anaylzed. For this cryomicroscope, the arrange of temperature reaches -10℃ ～ +40℃, the minimum cooling rate can reach 5℃/min and the maximum warming rate can reach 10℃/min, the static precision can reach ± 0.5 ℃The following is about the main work of this task:1. According to the requirment of user, give a design of the platform of the whole system. PC is elected as a contol unit. The temperature signal is gathered by A/D data collection card. The common microscope is also being refited.2. The part of hardware is designed and realised. Such as Pt100 temperature sensor, hot resistance signal conditioning and H bridge reversible driver.3. The part of software is designed and realised. It’s written by Visual Basic 6.0 with a friendly Man-machine interface, and consisted of hardware interface programming, data sampling, digital filter, data processing, PWM output, etc.4. Due to the characteristics of the controlled object are big delay lag and big inertia, a kind of control arithmetic named piecewise fuzzy intergral control is designed. Because of good adaptability and dynamic performance, fuzzy control without accurate mathematic model is applied on the first level. The second level is applied with self-adjust fuzzy PID control. It has good static precision, robust and reliability.From the results of experiments, they are substatiated that the piecewise fuzzy intergral control presented in this paper is effective for更多还原