基于BP神经网络算法的粉碎机自适应控制系统设计

针对饲料加工行业中锤片式粉碎机控制系统存在启动时间长、响应速度慢及负载变化时出现的稳定性差等问题,提出了一种基于BP神经网络算法PID控制方法。首先,建立变频器和饲料粉碎机驱动电机组合系统传递函数的参考模型,并对其进行稳定性分析。然后在分析常规PID和模糊PID控制算法的基础上,将自适应神经网络算法PID应用到饲料粉碎机驱动系统的控制过程当中。通过搭建饲料粉碎机控制电机的仿真模型,利用MATLAB软件中的Simulink图形化编程功能对其进行仿真分析,并基于LABVIEW软件搭建了粉碎机测控系统试验平台进行实验测试分析。结果表明：对于饲料粉碎系统所给定的速度参考模型,设计的BP神经网络PID控制器能够实现较好的自适应追踪,对阶跃信号的响应更加迅速、超调更小,抗干扰能力更强。设计的自适应控制器能够根据工况变化自动调节PID参数,吨料电耗平均降低5.16%、生产率平均提高2.08%,对粉碎机主轴转速的控制更加精确,误差更小,兼具了较高的控制精度和较强的鲁棒性,满足饲料粉碎机驱动系统的自适应控制要求。     

大型H型钢生产线轧机主传动系统选型

交-交变频传动系统和交-直-交变频传动系统在轧钢生产领域的应用较为广泛,以大型H型钢生产线轧机主传动选型为基础对两种系统进行了研究.通过对比两种传动方式在系统结构、工作原理、性能指标等方面的不同,确定了系统应用的方向.大型H型钢主传动系统依据这些研究数据进行了选型并成功地在生产线上进行了应用.     

Evaluation of mill drive options

Mill drives in the cement industry cover a wide range of mechanical drive and motor applications. This paper includes an overview of the various mill drive options with an emphasis on single motor drives. A more detailed review of the most recent drive development, the compact drive, is featured. In addition, a case study of a mill application is presented to show the effects on voltage drop. The paper concludes with comparative costs on the various combinations of drives and motors     

球磨机节能策略与控制方法

球磨机是水泥、陶瓷、冶金以及塑料粉末生产等企业中物料粉碎不可缺少的重要设备.目前有相当多球磨机及其拖动系统还处于非经济运行状态.球磨机启动的大电流,运行的低效率,是造成球磨机工作时电能严重浪费的主要因为.针对球磨机工作特点和要求,研究球磨机节能的策略,分析并给出影响球磨机用电效率的3个关键因素:电压、转差和功率因数;在...     

A High-Performance Cycloconverter-Fed Synchronous Machine Drive System

A high-performance variable-speed drive system using a cycloconverter-fed synchronous machine is described. The principle of the drive control is based on the field-oriented control method. For operating the synchronous machine drive system with high dynamic performance and excellent static characteristics over a wide range from zero to top speed, accurate field orientation and high response current control are particularly important problems to be solved. New methods of solving these problems are presented. This systems was manufactured for a 2500-kW reversible rolling mill drive system, using a six-pulse three- phase cycloconverter and an ordinary rotating field type synchronous machine without any special requirements. The expected performance was successfully obtained.     

球磨机新型控制策略研究与应用

球磨机制粉系统是电厂除锅炉燃烧系统外的又一重要调节系统。该系统具有多变量强耦合、非线性严重以及生产工况变化大等特性,采用常规控制策略很难奏效。在对球磨机动态特性分析的基础上,提出了一种新型控制策略。该控制策略采用软测量技术获取磨负荷信息,通过协调器实现对球磨机的磨负荷和出口温度的有效控制。通过控制热、冷风量的比值实现对球磨机入口负压的控制。控制器均采用模糊PID控制算法,以确保动态响应和稳态精度。实际运行效果表明,该控制策略具有简单、可靠、实用等特点。     

MPS-170HP-Ⅱ型磨煤机工作特性试验研究

通过对MPS-170HP-Ⅱ型中速磨煤机的工作特性试验,得出了磨煤机出口静态分离器特性、磨煤机液压加载压力特性和磨煤机通风量特性。根据工作特性试验的结果,提出了磨煤机的运行调整方法,对锅炉和磨煤机的经济运行具有一定的指导作用。     

ABB中压传动系统在钢管轧制中的应用

在天津钢管公司168新型钢管厂钢管轧制中,穿孔机主传动同步电机驱动应用了ABB公司先进的ACS6000中压变频调速传动系统。该系统是以IGCT为功率元件的一种中性点钳位整流变换器。详细介绍了该厂ACS6000中压变频传动系统的组成结构、送电、停机操作和在轧钢系统的应用以及常见的故障处理方法,提供了运行曲线。经过实践,证明了该系统具有响应速度快,控制精度高,运行稳定,可靠性好等特点,并提高了生产效率。     

Multiengine electric drive of pipe cold-rolling mill

The article discusses the requirements for electric drives for feeding and rotating a billet in a pipe cold-rolling mill, selecting types of electric drives, developing a control system, and conducting experimental studies of electric drives in an operating cold-rolling mill.     

Selection criteria for SAG mill drive systems

The various options available for large-horsepower semiautogenous grinding (SAG) mill drive systems are examined, together with their impacts on mill design and relative capital and operational costs. A brief history of large-mill drive systems is given. State-of-the-art mill design and mechanical design considerations are also discussed. A design for fixed-speed or variable-speed operation is presented, and the capital and operational cost factors that influence design are considered. The choice of a drive system is independent on the size of the mill, its critical speed, and the horsepower required. Several areas of concern are outlined for each drive-system design. A criterion for selecting the best design for large mills is developed     

有限能量电源供电复杂工况电驱动系统

电动车的研发为电驱动系统的研究提供了一个新领域。电动车电驱动系统不是一个简单的电拖动系统．而是有限能量电源供电，复杂工况下工作的电驱动系统。文中阐述了电动车电驱动系统的工作条件、供电电源的特性、电动车运行的工况特性．以及在这种工作条件下电驱动系统的设计特点。     

Synchronous and slip-ring induction motors drive cement mills

In the process of selecting a suitable motor for a cement mill, there are several issues to consider that, for the purpose of analysis, can be grouped into two distinct categories. The first category is the technical analysis, which is based on engineering considerations that evaluate the merits of either a synchronous or a slip-ring induction motor installation. The second category is the economical analysis, which follows closely the results of the technical evaluation with emphasis on the original investment cost and the cost of operating and maintaining the equipment over its useful lifespan-estimated as 30 years. Among the technical issues, the first should be identifying the torque requirements and initial power system limitations. The choice of motor design will largely depend on these requirements. The other issues relate to electrical energy savings. With the cement mill being the largest single power consumer in the plant, the choice of motor and drive will directly influence these savings, which can be significant. Several cement mill installations in operation today are discussed     

300MW燃煤机组混燃秸秆成型燃料的试验研究

该文利用已有制粉系统对成型生物质进行磨制并送入炉内燃烧,在300MW煤粉炉内实现了生物质的规模化利用。试验对生物质可磨性及磨煤机安全性进行分析;研究生物质混燃对火焰、温度、锅炉效率及污染物排放的影响。研究表明:辊式磨煤机和直吹式制粉系统,可用于成型生物质的磨制输送;生物质燃烧器喷口火焰稳定;生物质混燃工况下的炉膛上部温度分布和排烟温度,均比纯烧煤粉时更低;煤粉炉在混燃生物质的工况下运行时,锅炉效率略有下降;生物质混燃相对于纯烧煤粉,NOx和SO2均有所降低。该文研究对生物质在我国现有大容量煤粉炉上的直接混燃具有指导意义。     

具有不确定性参数的轧机主传动系统自抗扰控制器设计

轧机主传动系统通常由直流电机驱动,其性能好坏直接影响板带材的产量和质量.针对轧机主传动系统存在不确定性负荷扰动和未建模动态的特点,首先建立了轧机主传动系统的模型,将不确定性负荷扰动和未建模动态视为一个综合扰动项,然后利用扩张状态观测器对综合扰动项进行观测和补偿,基于自抗扰控制技术设计了一个不依赖于对象模型的轧机速度鲁棒控制器.仿真结果表明:该控制器不仅有效地抑制了不确定负荷扰动的影响,同时对系统内部参数如电机转动惯量、电枢电阻等的摄动也具有较强的鲁棒性.     

Large Grinding Mill Drives Update

The trend to larger grinding mills with the attendant increase in motor drive horsepower has affected the options for drive equipment. Also the development of large adjustable speed drives has created new possibilities for mill drives. Grinding mill torque characteristics, drive requirements, and torsional excitations of the various types of available drives will be briefly reviewed.     

Human-machine interfaces

Increased system complexity, reduced personnel, and tighter operating margins have made a AC or DC drive-system trending HMI not just a possibility, but a necessity in today's paper mill. Each new paper machine, coater, supercalender, or winder drive system should be installed with a modern user-friendly HMI. Existing analog and digital drive systems can be retrofitted with an HMI. This HMI should be used by operations and maintenance personnel to troubleshoot drive system, mechanical, and process issues. The majority of the issues that will be resolved with the HMI are process or mechanical related issues. The HMI should have trending capability, an overview screen, an event-history page, a sheet-break status screen, an alarm/fault-history page, and a permissive-screen page. The historical information that the HMI offers is what makes the tool invaluable.     

Rotary Grinding Mill and Drive Motor Torque Relationships

An understanding of torque relationships in the operation of rotary grinding mills necessitates a complete analysis of the mill, gear train, and drive motor insofar as torsional load, inertia, and frictional losses are concerned. Ability of a drive motor to develop the required torque is dependent upon its inherent torque characteristics in combination with its electrical supply system. A complete evaluation of both the drive motor and power system is therefore necessary to assure that proper torque will be supplied by the drive motor for the mill requirements.     

The method for determining the ball load and the grinding capacity of a ball-tube mill from the power consumed by its electric motor

The method for determining the ball load and the grinding capacity from the power consumed by the ball-tube mill under operating and emptying conditions is presented. The implementation of this method when grinding gas coals in the ball-tube mill of the ShBM 370/850(Sh-50a) type is discussed.     

15000-HP gearless ball mill drive in cement-why not!

Over recent years, there has been a clear trend toward higher capacity cement production units. Five to ten years ago 2500 tons per day was large. Nowadays in Asia, lines are built for 10000 tons per day. The development of ball mill grinding units has not shown the same trend; output and ratings have remained more or less constant perhaps due to the success of pregrinding with high pressure grinding roll technology. This lack of movement toward larger mills is somewhat surprising since in the same period the drive rating of ball mills for similar duties such as ore grinding has shown an increase in drive ratings from 3000-15000 hp. Ball mills in this power range are equally, when not more, efficient than their smaller counterparts and are capable of processing the total daily production within the overnight low-tariff period for electrical energy. Significant energy and cost economies can be achieved with a gearless mill drive working with a ball mill in these upper power ranges. This prospect should also be of interest to the cement industry. The technology is available for an up-sizing of cement grinding installations and the gearless mill drive is a proven, reliable drive     

可逆冷轧机电控系统几个问题的探讨

讨论了设计一套经济、高效的可逆冷轧机组电控系统应注意的几个问题。并以西门子直流调速装置6RA70和交流调速装置6SE70为例,介绍了可逆冷轧机组卷取系统供电方案、主机系统负荷平衡的实现、卷径计算的方法,探讨可逆冷轧机组电控系统设计和调试可优化改进的地方。