某机组ETS系统DCS系统一体化改造

针对某厂1号机组ETS系统设备老化,可靠性低以及系统本身无历史追忆等情况,对ETS系统DCS系统一体化进行可行性研究,选用由主机DCS厂家生产的硬逻辑实现汽机保护ETS-V系统,利用机组停机检修机会对ETS系统进行改造,结合改造对三重冗余LPC模件的ETS系统进行说明,取消单点保护,所有保护信号采用冗余配置,对改造后的ETS系统进行各项性能测试和各工况试验。结果表明,ETS系统可靠性和稳定性大大提高,和主机DCS实现无缝衔接,ETS系统DCS系统一体化得到成功应用。     

ETS系统常见故障及可靠性研究

介绍了双PLC控制的ETS系统的硬件构成及逻辑功能,对ETS系统的典型故障进行了分析,并提出了提高ETS系统可靠性的一些建议。     

探究ETS系统存在的问题及解决对策

在大型单元机组中,ETS系统发挥着关键作用,一旦汽轮机出现危急跳闸,ETS系统便会成为发挥出口的作用,对机、炉等一体化实施保护,因此,ETS系统是发电厂中重要组成部分,同时也是对系统可靠性和安全性要求较高的部分,对汽轮机的重要参数起着监视的作用,然而,在汽轮发电机组中,ETS系统也存在着诸多问题。对此,本文通过对ETS系统存在的问题进行了详细分析,并提出了相应的解决策略,为大型发电机组的安全运行提供了可靠保障。     

汽轮机危急跳闸系统设计研究

汽轮机危急跳闸系统(ETS)是保护汽轮机组安全的重要设备。为了保证ETS系统设计的可靠性,文中从ETS系统的设计原则,典型机组保护参数,ETS系统的实现方案入手,对ETS系统的设计进行了阐述,对ETS系统的设计具有一定的指导意义。     

300MW汽轮机危急遮断系统优化

为提高现有300 MW发电机组汽轮机危急遮断保护系统(ETS)的可靠性,将成熟的PLC控制等技术应用到保护系统控制逻辑的实现中。首先从危急遮断保护系统的原理入手进行了分析,建立了被测点和控制量之间的逻辑关系,采用了PLC控制等技术,来对双网双机双电源热备进行了优化。最后,对吴泾热电厂2台300 MW机组汽轮机危急遮断保护系统进行了优化。研究结果表明:采用该技术进行优化能极大地避免由于单点测量故障、单控制回路和单电源引起的发电机组汽轮机危急遮断保护系统的非正常保护动作。     

浅谈DCS系统中重要保护的故障类型及安全措施

从FSSS系统中2台DPU故障、ETS系统中2台DPU故障、FSSS系统中任一台DPU故障、ETS系统中任一台DPU故障FSSS或ETS系统2路交流电源故障5个方面，对DCS系统中重要保护的故障类型及安全措施进行了介绍和分析。     

某燃机电厂5#汽机ETS系统的DCS一体化改造

介绍了汽轮机ETS系统的DCS一体化改造工作,ETS系统改造前后硬件对比及改造后的调试试验,改造后的ETS系统性能更加可靠、功能更加完善。     

核电汽轮机安全仪表系统设计优化

分析了国内汽轮机安全仪表系统涉及标准规范的推荐性和强制性要求。采用某型核电汽轮机及其相关工艺系统HAZOP分析结果,编制风险矩阵进行LOPA量化分析,对ETS保护回路进行固有风险数据分析、独立层识别、剩余风险计算以及可接受性判断,完成了作为SIS系统的ETS保护回路功能安全的合理分配与优化,具有一定的工程实际应用价值。     

第四十六讲:功能安全型控制系统在1000MW机组ETS系统的应用

本文介绍了功能安全型控制系统在1000MW汽轮机危急遮断系统(ETS)中的实践应用,并针对汽轮机ETS项目进行危险与可操作性(HAZOP)分析和安全完整性等级(SIL)评估,同时首次将功能安全概念运用到发电厂汽轮机控制系统。     

KNX中国组织成功举办了2016“KNX新技术培训研讨会”暨“KNX中国应用奖颁奖典礼”

正2016年3月在德国法兰克福Light+Building展会上,KNX国际协会隆重推出了继KNX智慧城市后的KNX IoT物联网城市、KNX网络安全以及硬件集成ETS等新思想、新概念。如何解决将KNX安装和英特网中的所有物体(设备)即物联网连接?如何实现KNX网络安全?如何简化ETS应用?以及大家关心的KNX RF无线控制等问题,成为目前所有KNX从业人员关注的焦点。为了将这些新热点、新技术推广给中国的KNX制造商,为他们在未来的KNX产品开发上提供     

飞机电动机轮设计及电动滑行系统仿真研究

为进一步提高飞机的地面滑行效率,节省滑行时间和燃油消耗,基于飞机电动滑行系统构想,提出了一种改造飞机主机轮为电动机轮的方案。介绍了飞机电动滑行系统的工作原理及组成结构,制定了飞机电动滑行系统传动方案,并在主起落架原有模型基础上进行部分改造,重新设计电动机轮驱动结构和安装方式。采用永磁同步电动机的空间矢量控制技术, 通过MATLAB/Simulink对电动滑行系统建立仿真模型,分析系统滑行性能。仿真结果表明：飞机自动滑行速度满足要求,传动方案合理可行。     

汽车主动悬架几种控制策略的比较研究

根据汽车二自由度主动悬架模型,结合振动控制的理论和技术,着重研究了被广泛应用的模糊控制、最优控制和模糊PID控制,并利用M atlab进行仿真,与被动悬架进行了比较。对车身加速度、悬架动挠度和轮胎动荷载3个性能指标进行了评价,不仅讨论了上述3种控制方法用于主动控制的优点,还指出了这些控制策略存在的不足。     

Control of nonlinear processes by using linear model predictive control algorithms

Most chemical processes are inherently nonlinear. However, because of their simplicity, linear control algorithms have been used for the control of nonlinear processes. In this study, the use of the dynamic matrix control algorithm and a simplified model predictive control algorithm for control of a bench-scale pH neutralization process is investigated. The nonlinearity is handled by dividing the operating region into sub-regions and by switching the controller model as the process moves from one sub-region to another. A simple modification for model predictive control algorithms is presented to handle the switching. The simulation and experimental results show that the modification can provide a significant improvement in the control of nonlinear processes.     

Model predictive control with amplitude and rate actuator saturation

In this work we show that the anti-wind-up-bumpless-transfer controller emerges from the structure of model predictive control (MPC) with quadratic objective and input constrains. The key to establish that relationship is the application of optimality conditions to the equivalent optimal control problem. The proposed framework employs a model of physical constraints as part of the controller architecture to ensure that the commands sent to the actuator do not exceed their specific limits and the internal states of the controller are well updated. Numerical examples are presented for illustrating the proposed control design methodology.     

高速电主轴联合矢量直接转矩控制建模与仿真

矢量控制和直接转矩控制是高速电主轴的高性能驱动控制方法,由于其良好的动态控制性能,被广泛应用于高速机床的核心部件高速电主轴的驱动中。根据高速电主轴矢量控制和直接转矩控制的基本方程,对这两种控制方法的共性进行了深入探讨。在此基础上,建立了联合矢量直接转矩控制系统原理框图及其Simulink仿真模型,并对额定转速为15000转的170MD15Y20型高速电主轴进行了联合矢量直接转矩控制仿真。仿真结果验证了所建模型的正确性,并具有优良的动态性能。     

Modeling,simulation and experimental validation of flow rate of electro-hydraulic hitch control valve of agricultural tractor

Advances in non-linear control theory have made it possible to develop controllers for non-linear dynamic systems in their nature. The low-cost proportional control valves of the hydraulic control system are examples of such a system where there is no linearity due to the structure of the valves and the flaws in the spool. However, the non-linear analysis and regulation of these hydraulic systems cannot be done without a proper valve model. This paper presents a methodology for the development of an efficient unified model of a three-point hitch (TPH) electro-hydraulic proportional control valve control system for agricultural tractors by means of a parameter estimation technique. Modeling and simulation of the proportional control valve was performed using MATLAB Simulink software. Parameter estimation methodology was used to optimize the effective orifice opening of the solenoid valve to meet the flow characteristics available in the manufacturer's technical data sheet for the proportional control valve model parameters. Such unified Simulink models are useful for simulation, practical capability testing, and non-linear control design. Modeling and simulation of electro-hydraulic hitch (EHH) control valve were made and simulation results were compared with actual experimental results. The simulation results of the TPH lifting and lowering time were found to vary 4 and 12.5 %, respectively with the experimental results. This type of parameterized valve models facilitates their implementation in dynamic simulation models of complex hydraulic systems.     

汽车悬架控制系统研究动态与展望

综述汽车悬架控制系统的基本类型，半主动控制和主动控制的控制策略。由于智能阻尼装置具有机械结构简单，动态范围大，能耗低等特点，是一种非常有前途的半主动减振装置。介绍电流变液体及磁流变液体和装置的主要特点与优点，并给出智能阻尼器的模型。着重论述几种控制方法在汽车悬架控制系统中的应用，探讨今后的研究方向和发展趋势。     

Robust output feedback distributed model predictive control of networked systems with communication delays in the presence of disturbance

In this work, an output feedback cooperative distributed model predictive control is developed for a class of networked systems composed of interacting subsystems interconnected through their states, in which it handles bounded disturbances and time varying communication delays. A distributed buffer based prediction strategy is used to compensate bounded delays and predict those states, which are coupled between subsystems that their actual values may not available due to delays. In the design of robust distributed model predictive control, distributed moving horizon estimation is employed so that convergence and boundedness of the estimation error are ensured. Furthermore, robust exponential stability of the closed loop system is established. The effectiveness of the proposed method is illustrated using two interconnected continuous stirred tank reactors.     

Nonlinear Model-Based Predictive Control Using a Generalised Hammerstein Model and its Application to a Semi-Batch Reactor

In recent years, much attention has been focused upon predictive control of nonlinear systems. The implementation of such a control strategy for real processes has greatly improved their performance. This paper deals with a model-based predictivecontrol (MBPC) strategy using a generalised Hammerstein model and its application to the temperature control of a semibatch reactor. Both unconstrained and constrained adaptive control problems are considered. A simple identification method based on the weighted recursive least squares method (WRLS) is used to estimate the model parameters on-line. An indirect adaptive nonlinear controller is designed by combining the predictive controller with an indirect parameter estimation algorithm. This adaptive scheme has been applied for the control of a semi-batch chemical reactor. Experimental results show that the performance of the generalised Hammerstein MBPC (NLMBPC) was significantly better than that of a linear model predictive controller (LMBPC). ID="A1"Correspondance and offprint requests to: Dr F. M'sahli, Department of Electrical Engineering, ISETKH, Avenue Hadj Ali Soua, 5070, Ksar Hellal, Monastir, Tunisia. E-mail: msahli-fn@iyahoo.fr     

Implementation of an adaptive fuzzy compensator for coupled tank liquid level control system

In this paper, an adaptive fuzzy control (AFC) system is proposed to realize level position control of two coupled water tanks, often encountered in practical process control. The fuzzy control system includes an adaptive model identifier and controller. The gains of AFC are obtained by using the fuzzy identifier model which is defined by real system outputs and control inputs. The parameters of fuzzy identifier model are adjusted online by using recursive least square algorithm. Because the controller has a recursive form it treats model uncertainties and external disturbances in an implicit way. Thus there is no need to specify uncertainty and disturbances for this controller design in advance. A well-tuned conventional proportional integral (PI) controller is also applied to the two coupled tank system for comparison with the AFC system. Experimentation of the coupled tank system is realized in two different configurations, namely configuration #1 and configuration #2 respectively. In configuration #1, the water level in the top tank is controlled by a pump. In configuration #2, the water level in the bottom tank is controlled by the water flow coming out of the top tank. Experimental results prove that the AFC shows better trajectory tracking performance than PI controller in that the plant transient responses to the desired output changes have shorter settling time and smaller magnitude overshot/undershoot. Robustness of the AFC with respect to water level variation and capability to eliminate external disturbances are also achieved. Experimental results show that AFC is a strong and a practical choice for liquid level control.