【作者】 张明；

【导师】 郝迎吉；

【作者基本信息】 西安科技大学 ， 机械电子工程， 2008， 硕士

【摘要】 注塑设备多点温度控制是拉丝机系统的重要组成部分,其控制性能的好坏、多点温度的准确调节、反应速度的快慢等直接影响拉丝机输出产品的质量。本文设计了一种基于单片机的温度监控系统,用于对拉丝机注塑设备中的温度进行监控。该温度监控系统的下位机由8051F与AVR两种类型的单片机构成,包括温度传感器组、功率加热系统等部分,远程操作系统由计算机通过CAN总线来实现。为了实现高精度温度测量,本系统采用了8051F350内部集成的24位高速率A/D转换器;每路超过20KW的大功率可控硅控制部分采用高速低功耗、抗干扰性强的Atmega48作为控制芯片,发出控制脉冲改变可控硅的导通,从而控制加热模块的输出功率以实现恒温控制;因加热系统是一个具有滞后、热惯性的多变量非线性时变系统,因此在控制过程中使用了PID (比例、积分、微分)算法对温度偏差(即温度给定值和温度过程变量值的差)进行运算以得出控制数据。同时,在软、硬件设计中采用的抗干扰措施提高了系统的可靠性。系统的软件设计包括计算机软件和单片机软件。计算机软件以Lab Windows/CVI6.0为开发平台,实现了单片机和计算机之间的可靠通信,并且完成了对数据的处理及实时显示,同时具有数据存储、曲线显示、打印输出等功能。单片机软件主要实现A/D转换、PID控制算法及输出控制脉冲等功能,编程中将温度采集、PID计算过程与计算结果的处理有机结合,实现了多路温控点的恒温控制。该系统已按期交付给用户,经过这段时间的实际使用,该系统软、硬件运行良好,各项技术指标均达到设计要求。更多还原

【Abstract】 The multi-point temperature control for plastic injection device is the important constituent part of wire drawing machines. Its functions of control, Multi-point temperature accuracy-tuned and the speed of response influence the product’s quality which is output from wire drawing machines. This article designs a temperature collecting and controlling system based on the single-ship, and it is used to collecting and controlling the temperature in the plastic injection device of wire drawing machines.The multi-point temperature collecting and controlling system uses a hardware part which consists of 8051F and AVR the two kinds of single-ships, and it is combined by temperature sensor and power heating system. The long-distance operating system is carried out by computer through CAN bus. This system uses 24 bit high speed A/D converter which is integrated in the 8051F350 so as to realize its high precision in temperature measure. The temperature controlling part uses Silicon Controlled Rectifier to control every way which is over 20KW high-power, and we choose Atmega48 which has high-speed, low-power, and strong antidisturbance character as the MCU, changing the breakover of the Silicon Controlled Rectifier by sending out the control pulse to control the export power of the heating system and realize constant temperature controlling. Because of the heating system is a multivariable and nonlinear system with large time delay and heat inertia, in the process we use the PID Method (proportion, integral, differential) to calculate the temperature error (the difference between the given temperature value and the collected temperature value) and gain the control data. At the same time, the antidisturbance method what we have used in the software and hardware improves the fail-safe nature of the system.The software design of the system includes computer software and the single-ship software. Computer software takes Lab Windows/CVI6.0 as the developing platform to realize the dependable communication between single-ship and computer, and it copes with the data and displays it in time. It also has other functions, such as, memories data, displays curve, prints out and so on. The single-ship software chiefly realizes A/D conversion, PID control method, and the controlling pulse output functions and so on. In the program, we realize multi-point temperature control by combining the temperature collecting, PID computing process and computing result reasonably.The system has been delivered to the users on time, and has been used in a period of time. This system works well and steadily, so it can satisfy the demands both manufacturers and users.更多还原