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1.
电抗器线匝的分布电流不均会导致局部过热,从而降低绝缘性能,进行电抗器的分布电流监测工作有助于及时发现故障隐患.从工程现场出发,运用多只传感器实时监测电抗器每一层包封的分布电流数据,并以无线发包方式将数据回传人监测系统.经实验证明:该系统能在电抗器工作环境下准确测得分布电流变化值,将为变电站内干式空心电抗器实时监测提供重要的理论依据和设备支持.  相似文献   

2.
《工矿自动化》2013,(11):45-49
在分析有源电力滤波器拓扑结构的基础上,研究了直流母线电压和进线电抗器的选择对有源电力滤波器无功补偿效果的影响,提出了基于电压平均值的电抗器改进选择策略。实验结果表明,直流母线电压为720V、APF侧电抗器值为1.5mH时,电网电流畸变率小,系统动态性能良好。  相似文献   

3.
研究输电线路中电抗器优化问题是提高输电效率的保证.为了克服传统数学物理方法计算电抗器电感量的繁琐和精度不高的缺点,同时直观地描述电抗器周围磁场的分布,针对特种水冷磁屏蔽电抗器,为保证输电系统的可靠性和电抗器的精确性.采用ANSYS软件仿真电抗器产生的磁场分布,并采用能量法计算出电抗器线圈的电感值.实验结果表明,ANSYS软件仿真电抗器磁场分布非常形象准确;计算电感值相当精确;能提高设计效率,有效降低研发成本,具有良好的工程应用价值,给出三维电磁场分析中建立双层空气模型的新方法,为设计提供了科学依据.  相似文献   

4.
为了使试验安全快速准确的进行,设计了一套简单实用的电抗器参数测试系统。采用异步串行通信,使用DWC-2多路温度测试仪采集8路温度信号,使用GDW3001三相电参数仪采集三相的电压、电流信号,并可显示功率、功率因数等。利用组态王编程,由PLC控制,完成对电抗值、损耗值等的优化计算,实现了保存数据到数据库、绘出实时温度曲线、统计报表、诊断故障、显示报警等功能。  相似文献   

5.
为了改善电网无功功率不平衡导致的电网电压巨大波动、功率因数低落等问题,设计了一种基于磁阀式可控电抗器的无功控制系统。该系统采用多变量控制策略,通过控制电抗器的输出感性无功,实现功率因数控制、母线无功功率和母线电压的连续调整。试验结果表明,多变量控制策略能有效应用于系统目标参数控制,达到了预期的效果。  相似文献   

6.
米娟芳  康朝红 《软件》2013,(10):126-126,137
针对电抗器的匝间短路提出了一种自适应补偿的短路保护方法,由系统零序回路零序源的所在位置来决定故障产生的位置,以提高匝间短路保护动作的灵敏度,同时克服了传统保护在系统无穷大时电抗器内部故障的死区问题,而在外部任何非正常运行工况下不会误动。  相似文献   

7.
介绍了磁控式可控电抗器的控制调节机理,并根据其系统的需求提出了一种基于光电转换的高电位整流器的监控系统,并给出了其硬件和软件的设计和实现。  相似文献   

8.
艾朝阳  章健  李耀 《微计算机信息》2008,24(11):160-161
提出了基于TMS320F2812的磁控电抗器的新型动态无功补偿方案.介绍了TMS320F2812的特点和磁控电抗器的原理,给出了基于TMS320F2812的磁控电抗器的软、硬件设计.  相似文献   

9.
针对能量回馈变流器并联模块间的环流问题,分析了并联模块之间不均流产生的原因及均流电抗器的工作原理,提出了一种抑制并联模块间环流的均流电抗器绕制新方法。详细阐述了均流电抗器的电气参数计算与选型方法,并对均流电抗器的运行工况进行了模拟仿真分折,实现了均流电抗器的合理化设计。DC 750 V能量回馈装置研制项目的试验结果证明了该均流设计方案的可行性。  相似文献   

10.
电力机车主变压器综合自动测试系统足具有多功能的综合大型试验设备,在本系统中,采用工业控制计算机作为上位机控制测试系统的所有试验过程和试验数据记录,可编程序控制器PLC完成各试验功能模块的切换,智能数字化仪表实现模拟量的转换和传输,系统工作稳定、准确,自动化程度高,能够完成SS7系列、SS3B、SS6B、SS4G等多种车型主变压器、功率补偿电抗器、滤波、平波电抗器、电流互感器的半成品试验和出厂试验;综合自动测试系统的使用大大提高了电力机车主机厂的生产效率,同时也提升了试验过程的科学性和试验操作的安全性。  相似文献   

11.
This paper presents a mathematical analysis of the unusual dynamics found in a coupled reactor/preheater process. The outlet temperature of the reactor exhibits inverse response (wrong-way behaviour) for a change in the inlet reactor temperature and a large deadtime. The coupling of the preheater with the reactor produces positive feedback, which makes the coupled process openloop unstable. Both theoretical linear analysis and simulation studies reveal some unusual dynamics and some interesting frequency response plots. The Nyquist plot of the openloop characteristic equation of the reactor itself is used to determine the number of poles in the right half of the s-plane (RHP) of the openloop characteristic equation of the coupled reactor/preheater system. For small values of reactor gain and small values of the positive-zero time constant, there is one pole; so the closedloop system is stable if the total openloop system (process plus controller) Nyquist plot encircles negatively the (−1,0) point. As the gain and positive-zero time constant are increased, a point of discontinuity is reached. This occurs when the Nyquist plot of the openloop reactor indicates two poles instead of one in the RHP. Now there must be two negative encirclements of the (−1,0) point for closedloop stability. For small values of the positive-zero time constant and reactor gain, the Nyquist plot of the coupled system does show two encirclements. However, for a given deadtime, there are maximum values for the positive-zero time constant and the reactor gain beyond which the closeloop system cannot be stabilized. One of the most unusual dynamic features of this system is the effect that reset (integral action) in the controller has on closedloop stability. Conventional wisdom says that adding integral action in a feedback controller always degrades dynamic stability and performance. However, in this coupled reactor/preheater process the addition of integral action can improve closedloop stability.  相似文献   

12.
为了提高核电厂反应堆冷却剂系统旁路温度的测量精度,建立了铂电阻温度计的温度-电阻特性曲线拟合模型和电阻-温度特性曲线模型,采用递推最小二乘法对样本数据进行拟合以确定特性曲线的模型参数。该方法根据铂电阻温度计的测量电阻值即可高精度计算出相应的温度。仿真结果表明,与现有方法相比,温度测量精度有明显提高,在温度检测领域具有重要的理论和应用价值。  相似文献   

13.
通过对Borstar双峰聚合反应过程产品性质实验分析,Borstar双峰聚乙烯技术超临界环管反应器生产聚合物熔融指数相对于分子量呈指数规律变化,气相反应器生产的聚合物熔融指数随分子量增加而呈一定规律的减少,聚合物分子量继续增加聚合物熔融指数减少趋势缓慢;在实验分析的基础上,基于聚合反应机理应用MATLAB软件建立工业装置聚合过程聚乙烯熔融指数及密度等产品性质计算模型和确定模型参数,通过模型拟合值和实际值的比较,模型能够准确预测熔融指数和密度的变化趋势,有关聚乙烯在环管中的熔融指数、在流化床内的熔融指数和密度的质量模型相对平均误差分别为2.4%,0.5%和0.3%。通过产品质量预测模型的推导和分析,环管部分熔融指数主要受温度、[H2]/[C2H4]影响;而气相部分熔融指数既受环管聚合物来料性质影响,又受气相反应器温度和[H2]/[C2H4]和[C4H8]/[C2H4]的影响  相似文献   

14.
A two-compartment four-cell model is developed for the adiabetic slim type autoclave reactor for free radical polymerization of low density polyethylene (LDPE). It is possible to determine not only the reactor performance represented by the monomer conversion and the reaction temperature but also the properties of the polymer product characterized by the average molecular weight and the polydispersity. It turns out that the reactor performance predicted is in good agreement with the plant data and the properties of the polymer product are estimated within reasonable ranges of actual values. The steady state multiplicity is found to exist and is examined by constructing the bifurcation diagram. The effects of various operation parameters on the reactor performance and the polymer properties are investigated systematically to show that the temperature distribution plays the central role for the properties of the polymer products. Therefore, it is essential to establish a good control strategy for the temperature in each compartment. The adaptive pole-placement control algorithm is applied to the temperature control of the adiabatic slim type autoclave reactor. The recursive least square method is used for the model identification. To accomplish a satisfactory control, the estimator and controller are initialized during the period of start-up. It is shown that the reactor system can be adaptively controlled by the pole-placement control algorithm, especially when the reactor temperature distribution is changed.  相似文献   

15.
本文提出了一种全新的聚合反应釜温度控制算法,用于解决实际生产过程中反应釜温度具有的纯滞后、大惯性、多变量耦合等特点。考虑冷却水管网压力、冷却水温度和进料流量等多个变量对反应釜温度的影响,建立更加准确的数学模型进行控制,控制效果更加精确。基于该算法的聚合反应釜温度控制系统已经开发成功,并在实际聚合反应釜生产上投入使用,取得了比较满意的控制效果,验证了该算法的有效性。  相似文献   

16.
The efficient control of an exothermic packed bed reactor is demonstrated in concert with the distributed parameter state estimation of temperature and concentration profiles and on-line estimation of the catalyst activity profile. The position-dependent catalyst activity is estimated using recursive least squares with a variable forgetting factor, a distributed mass balance model and the current estimated temperature profile. The temperature level in the reactor is regulated through control of the maximum estimated reactor temperature using the reactor coolant temperature as the manipulated variable. These methods are demonstrated both through closed-loop simulation and experiments with a laboratory-scale reactor for the partial oxidation of methanol. The experiments included both setpoint changes and disturbance rejection. The estimation and control system effectively overcomes errors in initial conditions, heat transfer parameters and kinetic parameters.  相似文献   

17.
在间歇反应过程的温度跟踪控制问题中,为了实现全工况范围内反应器温度设定值的精确跟踪,设计了一种改进的预测控制算法.在反应自身产热对系统输出影响未知的情况下,用带有输入干扰的系统模型来建模夹套温度与反应温度之间关系,并将该干扰项增广为状态变量,然后结合线性卡尔曼滤波器估计出干扰的大小及其时系统输出的影响;结合估计出的干扰,在DMC控制算法对其加以补偿.最后在半实物的仿真环境中,验证了该控制算法在间歇温度控制中的效果,结果表明,该控制方法在一定程度上克服了反应产热对温度跟踪精度的影响,改善了控制效果.  相似文献   

18.
反应釜炉温控制是化工生产过程中主要的控制系统之一,其温度控制具有大滞后、时变、非线性等特点.针对常规PID控制效果不佳的缺点,提出一种改进的模糊RBF神经网络智能控制方法.将系统的输入误差及误差变化率进行模糊化,并利用RBF神经网络算法对PID控制参数进行在线学习、运算和整定.在RBF神经网络控制算法中,设定初始权值在一定范围内服从高斯分布和均匀分布,对权值不断优化,使得反应釜温度达到良好的控制效果.经Matlab仿真验证,结果表明和常规PID相比,该方法提高了系统的控制精度并具有较强的鲁棒性.  相似文献   

19.
《Journal of Process Control》2014,24(7):1076-1084
In this paper an approach based on system identification is used for fault detection in a nuclear reactor. A continuous-time Extended Kalman Filter (EKF) is presented, which allows the parameters of the nonlinear system to be estimated. Also a fault tolerant control system is designed for the nuclear reactor during power changes operation. The proposed controller is an adaptive critic-based neuro-fuzzy controller. Performance of the controller in terms of transient response and robustness against failures is very good and considerable.  相似文献   

20.
A new chemical reactor, the Open Plate Reactor, is being developed by Alfa Laval AB. It combines good mixing with high heat transfer capacity into one operation. With the new concept, highly exothermic reactions can be produced using more concentrated reactants. A nonlinear model of the reactor is derived and a control system is developed. For temperature control a cooling system is designed and experimentally verified, which uses a mid-ranging control structure to increase the operating range of the hydraulic equipment. A Model Predictive Controller is proposed to maximize the conversion under hard input and state constraints. An extended Kalman filter is designed to estimate unmeasured concentrations and parameters. Simulations show that the designed control system gives high conversion and ensures that the temperature inside the reactor does not exceed a pre-defined safety limit.  相似文献   

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