摘 要
随着科学技术的发展，PLC控制系统在工业控制系统中的应用越来越广泛。在工业数字化生产的过程当中，PLC控制系统的可靠性直接影响到工业企业的安全生产和经济运行，系统的抗干扰能力是系统可靠运行的关键所在。应用于工业中的控制系统大多是在强电路和强电设备所形成的恶劣电磁环境中运行的，所以设备在运行过程中会受到各种各样的干扰。有来自控制系统内部的干扰，也有来自外部的干扰。在使用时如果装配不当，将会使控制电路因受到干扰而无法正常工作。因此，要提高PLC控制系统的可靠性，一方面要求PLC生产厂家提高设备的抗干扰能力；另一方面，要求在工程设计、安装施工和使用维护中高度重视，多方面配合才能完善PLC的应用，有效增强系统的抗干扰能力，将干扰的影响控制在最小。
本文从控制系统抗干扰设计的常用措施入手，首先分析了电磁干扰的形成及传播的基本理论。其次从硬件方面来分析抗干扰措施，从器件使用中的抗干扰措施、电路设计抗干扰措施两方面入手，并对其进行适当的展开分析。最后从控制系统装配方面介绍了一些抗干扰措施，如电场屏蔽、磁场屏蔽、电磁场屏蔽。
虽然控制系统的抗干扰措施种类很多，但是每项措施都有很强的针对性，所以在选择抗干扰措施的时候应当结合实际情况，合理采取抗干扰措施，这样才能使抗干扰的效果发挥到最好，否则就会适得其反。
关键字：控制系统 电磁干扰 屏蔽技术 设计
Oil cooler assembly control system anti-interference design
Abstract
With the development of science and technology, PLC control system is more and more widely used in industrial control system. In the industrial production process of digital, the reliability of PLC control system directly affects the safety of industrial enterprises and economic operation, system anti-jamming capability is the key to reliable operation. The control system which used in industry is mostly in the strong and strong electrical circuit formed by devices running harsh electromagnetic environment, therefore, the process equipment will be running a variety of interference. Not only from the interference of the internal control system, but also from external interference. If the assembly when used improperly, it will make the circuit can not be due to disruption of normal work. Therefore, to improve the reliability of PLC control system, one side we should ask the PLC manufacturers to improve equipment, anti-jamming capability; the other side, we should require engineering design, installation and construction and use of high priority maintenance, it can perfect the application of PLC only coordinate with in many different areas, effectively enhance the system's anti-jamming capability, the interference of control to a minimum.
This article from the control system commonly used anti-interference measures designed to start, first analyzed the formation and propagation of electromagnetic interference of the basic theory, the second, from hardware to analyze the anti-interference measures in this regard, anti-interference measures both circuit design aspects, and to analyze its appropriate from the device using the anti-interference measures. Final assembly area from the control system introduces a number of anti-interference measures, such as electric field shielding, magnetic shielding and electromagnetic shield.
Although the control system of many kinds of anti-interference measures, but each of these measures is highly relevant, therefore, interference in the choice of measures should be combined when the actual situation of reasonable measures taken to interference, the effect of anti-interference play to the best only on this way, otherwise, it will backfire.
Keyword: control system; electromagnetic interference; shielding; design
