风机PLC系统端口电磁兼容及可靠性设计

发布时间：2018-04-15 03:37

本文选题：风机主控系统 + 可编程控制器　；参考：《湘潭大学》2017年硕士论文

【摘要】：作为风能资源利用最有效的方式,风电已成为我国可持续发展和经济增长的重要组成部分。可编程控制器(PLC)作为风力发电系统的核心部件,需适应复杂的工作环境,且风机控制系统对PLC的稳定性和可靠性要求更高。在工业控制中,通常用电磁兼容性能优良来衡量PLC系统的稳定可靠性是否满足要求。本文结合“风机主控PLC系统国产化”项目,针对国产化PLC系统在风机试运行阶段出现的各种EMI干扰问题,提高国产化PLC系统的电磁兼容性能迫在眉睫。本文在电磁兼容理论分析的基础上,提出了一整套针对国产化PLC电磁兼容问题的解决方案,并将这套方案成功的融入到国产化PLC设计流程中。在综合分析现有电磁兼容设计技术的前提下,吸取其中有利于提高国产化PLC电磁兼容可靠性的设计方案,利用仿真工具对设计方案进行分析;最后,通过工程仪器对整套国产化PLC系统进行电磁兼容可靠性验证。本文主要完成的工作有:(1)PLC电磁兼容技术研究难点与关键技术。结合国内外PLC电磁兼容现状,分析了PLC进行电磁兼容设计存在的问题;本文分析了风力发电控制器机组中的干扰源和干扰信号,包括其传播途径和耦合方式,将干扰方式分解为弱磁场耦合和弱电场耦合,建立各自的二端口电路模型计算干扰电压和电流。对常用的电磁兼容技术包括屏蔽、滤波、接地、隔离等技术特点进行分析,提出适合于本文的电磁兼容设计拓扑结构;(2)电磁兼容原理图设计和仿真实现。对国产化PLC系统的通信端口包括以太网端口、CAN端口、总线适配器端口、电源端口、数字、模拟传感器信号端口进行电磁兼容原理图设计。使用Altium Designer软件对PCB板进行电磁兼容设计和仿真验证。文中分析了两种器件建模的优缺点,得出IBIS模型的优势,并对PCB进行了信号完整性和电源完整性仿真验证;(3)实例验证。通过浪涌信号发生器、脉冲群信号发生器对本文所设计的电磁兼容解决方案进行验证,使用上位机软件显示验证结果,对不完善的设计分析其原理,更改设计方案,然后再次进行验证;本文所讨论的电磁兼容方案已取得3C认证证书,应用于郴州大冲风电场,提高了PLC运行的安全性和可靠性,具有良好的应用前景。
[Abstract]:As the most effective way to utilize wind energy, wind power has become an important part of sustainable development and economic growth in China.As the core component of wind power system, PLC (Programmable Logic Controller) needs to adapt to the complex working environment, and the stability and reliability of PLC are higher in the fan control system.In industrial control, EMC performance is usually used to evaluate the stability and reliability of PLC system.In this paper, according to the project of "nationalization of main control PLC system of fan", it is urgent to improve the EMC performance of home-made PLC system in view of the various EMI interference problems that occur in the trial operation stage of domestic PLC system.Based on the analysis of EMC theory, this paper puts forward a set of solutions to the domestic PLC EMC problem, and successfully integrates this scheme into the domestic PLC design process.On the premise of synthetically analyzing the existing EMC design technology and absorbing the design scheme which is helpful to improve the reliability of EMC in domestic PLC, the design scheme is analyzed by simulation tools. Finally,The electromagnetic compatibility reliability of the whole PLC system is verified by engineering instruments.The main work of this paper is to study the difficulties and key technologies of EMC technology.Combined with the current situation of PLC EMC at home and abroad, the problems in EMC design of PLC are analyzed, and the interference sources and interference signals in wind power controller unit are analyzed, including its propagation path and coupling mode.The interference mode is decomposed into weak magnetic field coupling and weak electric field coupling, and their respective two-port circuit models are established to calculate the interference voltage and current.The characteristics of electromagnetic compatibility (EMC) technology, including shielding, filtering, grounding and isolation, are analyzed, and the design and simulation of EMC schematic diagram suitable for this paper are put forward.The communication ports of home-made PLC system including Ethernet port can port bus adapter port power port digital port and analog sensor signal port are designed for EMC schematic design.Altium Designer software is used to design and verify the EMC of PCB board.This paper analyzes the advantages and disadvantages of two kinds of device modeling, obtains the advantages of IBIS model, and verifies the signal integrity and power integrity of PCB by simulation.The EMC solution designed in this paper is verified by surge signal generator and pulse group signal generator. The software of upper computer is used to display the verification result. The principle of imperfect design is analyzed and the design scheme is changed.The EMC scheme discussed in this paper has obtained 3C certification and has been applied to Chenzhou Dachong wind farm, which improves the security and reliability of PLC operation and has a good application prospect.
【学位授予单位】：湘潭大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TP273;TN03;TM315

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