液体流量串级控制系统方案设计书.docVIP

北京化工大学 毕 业 设 计 题 目：流体流量plc控制系统设计 专 业： 生产过程自动化 班 级： 甘自专131 姓 名： 张秀娟 学 号： 131056 指导老师： 完成时间： 年月日 摘 要 随着现代工业生产过程向着大型、连续和强化方向发展，对控制系统的控制品质提出了日益增长的要求。在这种情况下，简单的单回路控制已经难以满足一些复杂的控制要求。串级控制系统是过程控制中的一种多回路控制系统，是为了提高单回路控制系统的控制效果而提出来的一种控制方案。串级控制系统把两个单回路控制系统以一定的结构形式串联在一起，它不仅具有单回路控制系统的全部功能，而且还具有许多单回路控制系统所没有的优点。串级控制系统采用了两个调节器，因此它的调节器的参数整定更复杂一些。 本论文论述了一个液位——流量串级控制系统的设计方法和步骤，介绍了它的参数整定方法。在此过程中，介绍了对液位和流量进行检测和转换的常用元件，应用阶跃响应曲线推导了广义对象的传递函数，简单地论述了串级控制系统的优点，讨论了它对控制效果的改善作用，并使用仿真软件对该系统进行了仿真，最后用组态软件编制程序来实现控制。 关键词：PLC控制系统；液位；流量；PID ABSTRACT Along with the modern industry production process to large-scale,continuously is developing with the strengthened direction, proposed to the control system control quality day by day grows request. In this kind of situation, the simple single return route control already with difficulty satisfied some complex control requests. The cascade control system is in the process control more than one kind of return routes control system, is for enhance one kind of control plan which the single return route control system the control effect proposes.The cascade control system two single return routes control system by the certain structural style connects in together, it not only has the single return route control system the complete function, moreover also has many single return routes control system no merit. The cascade control system has used two regulators, therefore it is more complex to set its regulator parameter. The present paper elaborated a fluid position —current capacity cascade control system design method and the step, introduced its parameter set method. In this process, introduced carries on the examination and the transformation commonly used part to the fluid position and the current capacity, has inferred the generalized object transfer function using the step leap response curve, simply elaborated the cascade control system merit,