白石水库尾水渠水位～流量关系曲线率定与分析

为率定白石水库尾水渠水位-流量关系曲线,以白石水库尾水渠为研究对象,利用实测数据计算出渠道的断面尺寸,根据渠道的实际情况选定理论流量计算公式和比降、糙率等系数,经过计算得出水位-流量关系理论曲线,再通过对水库渠道内低、中、高水位下测流方法的选择,确定在低水位和高水位下采用浮标法,在中水位下采用流速仪法,并将多次实测结果与理论值进行比较,发现两者差值均在误差范围内,吻合度非常高,最终验证所绘制的白石水库尾水渠水位-流量理论关系曲线采用的理论公式和参数准确、合理,曲线精确度符合水库的实际需求,以此为水库流量测验提供可靠的技术支持,同时也为同类型水库的尾水渠计算下泄流量提供宝贵经验,可用于今后的泄洪流量测算。     

基于多断面水位-流量法的渠道流量测量技术

由于受到闸门启闭造成的回水影响,渠道水位-流量测量模型由单值模型变为了多值模型,常规测流方法不再适用。针对存在回水问题的渠道流量测量,提出了多断面水位-流量测量方法,利用神经网络逼近任意非线性函数的特性,建立了基于神经网络的多断面水位-流量关系模型。通过实测数据表明,所建立的多断面水位-流量关系模型的流量预测精度比常规水位-流量关系法更高。根据所建立的关系模型,设计了基于无线传输的水位采集装置和流量测量装置,并应用于渠道流量测量。     

浙江省灌区计量设施率定中的问题与对策

灌区用水计量设施率定是实现灌区取用水监控由水位/电量向水量转化的关键,为保证率定工作的正常开展和率定数据的真实可靠,在总结浙江省335处用水计量设施率定工作中遇到的困难的基础上,从率定技术路线,率定数据采集和保存,率定数据计算和分析等方面提出相对应的解决方案,以期为同类率定工作的开展提供经验借鉴。     

基于电话网的灌区水情数据远程监测系统

介绍了用电话网实现灌区水情数据远程监测系统的设计方案,根据水位-流量曲线法测量原理计算出水位、流量数据,给出测点单片机控制Modem远程通信接口电路和软件设计框图。阐述了上位机与单片机的通信协议、上位机设计思路和实现方法。最后给出灌区水位、流量实时监测的运行结果。     

移动雷达波测流系统在松柏水文站的运用

针对松柏水文站在发生暴雨洪水时河流陡涨陡落,高洪时漂浮物多,采用流速仪或ADCP测流不安全的问题,应用移动雷达波测流系统进行流量测验。在分析测流系统组成、工作原理、管理软件的基础上,按照不同水位级布置测次,采用同期测流系统施测流量与转子式流速仪人工实测流量进行比测,建立2种流量相关关系,率定测流系统流量系数,并进行误差分析评判,验证移动雷达波测流系统测流精度。比测率定结果表明:两者相关关系良好,移动雷达波测流系统测得的水面流速经率定后,推算的断面流量精度较高,满足水文资料整编精度及水资源管理要求,可提高水文资料时效性和准确性,解决山溪性河流流量测验安全问题。     

基于TCP／IP的水利试验测控系统设计

本文介绍一种基于TCP／1P协议的新型水力物理模型试验测控系统，该系统将目前最先进、最流行的工业以太网技术应用到物理模型试验研究的测控系统中，实现多点水位、流速和流量等水力学重要参数的实时采集、处理、储存、显示及打印，并具有在线查询及数据分析功能。     

中小型水库蓄泄关系探讨

以双树寺水库为例探讨中小型水库蓄泄规律。在各种类型的水库建筑物上设置合理的水文要素关系观测设施,配合水文站测验断面的实测资料进行参数分析。率定了水电站单机功率～效率关系,锥形阀出流量与库水位及开启度之间的关系,溢洪道弧形闸门闸孔出流流量系数关系及泄流曲线。为中小型水库蓄泄关系率定寻找一种有效途径。     

基于PLC和LabVIEW的液压式定重装载监控系统设计

针对箕斗提升采用压磁定重装置存在现场使用效果不理想的问题,提出了一种基于PLC和LabVIEW的液压式定重装载监控系统的设计方案;给出了液压式定重装载的工作原理,详细介绍了该系统的硬件、软件设计及LabVIEW与PLC的通信实现。实际应用表明,该系统运行稳定、可靠,适合现场使用。     

上海浦东水闸过闸流量和水量率定方法研究

上海地区受河道感潮、地势平坦等自然情况影响,采用传统的流量率定方法,一般难以得到稳定的相关关系曲线。为此探讨上海浦东地区过闸流量、水量率定方法,重点将水力学堰闸过流公式与水文统计学多元回归方法相结合,对过闸水量作率定分析。并根据率定公式,实现对三甲港水闸过闸水量的推求,实际应用说明,基于堰闸公式并结合多元回归方法对于推算水量更为实用。     

落差指数法在大湟江口水文站流量在线监测的探讨

河流水能资源梯级开发对水文站水文监测造成了较大的影响,水位流量关系变得散乱,在洪水涨落过程或水利工程回水影响期,现用的综合水位流量关系法推算的实时流量可能出现较大偏差。为应对受水利工程回水等因素影响下的水文监测难题,探讨用落差指数法对受影响水文站水位流量关系进行单值化处理,用实测水位信息推算出实时流量,从而实现流量在线监测。以珠江流域西江干流大湟江口水文站为例,用该站 2017 年以来的实测资料,对落差指数法有关参数进行率定,以单值化关系推算流量。分析结果表明：所推算流量的精度满足规范要求,基本解决大湟江口水文站受影响后的流量实时在线监测和水文资料整编定线难题,可为开展西江干流浔江河段水情预警、生态流量监控、水文分析评价提供良好的实时流量信息支撑。     

SCADA system with predictive controller applied to irrigation canals

This paper applies a model predictive controller (MPC) to an automatic water canal with sensors and actuators controlled by a PLC network (programmable logic controller), and supervised by a SCADA system (supervisory control and data acquisition). This canal is composed by a set of distributed sub-systems that control the water level in each canal pool, constrained by discharge gates (control variables) and water off-takes (disturbances). All local controllers are available through an industrial network managed by the SCADA system, where the centralized predictive controller runs.In this paper a complete new platform connecting the SCADA supervisory system and the MATLAB software (named SCADA–MATLAB platform) is built, in order to provide the usual SCADA systems with the ability to handle complex control algorithms. The developed MPC-model presents a novelty in the control of irrigation canals as it allows the use of industrial PLCs to implement high complex controllers, through the new developed SCADA–MATLAB platform.Experimental results demonstrate the reliability and effectiveness of the proposed strategy in real-life typical situations, including gate malfunctioning and extreme water off-take conditions.     

智能浮子式水位计

智能浮子式水位计是为引黄灌渠斗口流量自动测量而研制的。它基于双微机协同工作,将粗测和精测相结合,具有较大的量程,较高的分辨力,可作为自记式和远传式水位监测仪器单独使用,也可通过RS-485总线联入智能测量网络,是引黄灌渠斗口流量自动测量装置中理想的智能水位传感器。     

A hierarchical distributed model predictive control approach to irrigation canals: A risk mitigation perspective

This paper presents a hierarchical distributed model predictive control approach applied to irrigation canal planning from the point of view of risk mitigation. Two levels in optimization are presented. At the lower level, a distributed model predictive controller optimizes the operation by manipulating flows and gate openings in order to follow the water level set-points. The higher level implements a risk management strategy based on the execution of mitigation actions if risk occurrences are expected. Risk factors such as unexpected changes in demand, failures in operation or maintenance costs are considered in the optimization. Decision variables are mitigation actions which reduce risk impacts that may affect the system. This work shows how model predictive control can be used as a decision tool which takes into account different types of risks affecting the operation of irrigation canals.     

Fractional robust control of main irrigation canals with variable dynamic parameters

A new method is proposed for controlling main irrigation canals with variable dynamical parameters based on robust fractional order controllers. A methodology for designing PID controllers robust to changes in the time delay and the gain is presented first. Then this method is generalized to design fractional controllers that exhibit the same robustness as the previous PID to time delay and gain changes, but are noticeably more robust to variations in the dominant time constant of the process. This method is applied to control main irrigation canals. Extensive numerical simulations using the dynamic model of a real canal were carried out. Then experimental results were obtained in a prototype canal that proved the effectiveness of the proposed control method in terms of performance and robustness.     

Water balance study and conjunctive water use planning in an irrigation canal command area: A remote sensing perspective

Water budgeting of the D-36 and D-36 A distributaries confined between Pedda Vagu, Korutla Vagu and Kakatiya main canal of the Sri RamSagar Project (SRSP) Command area was conducted using remote sensing derived crop areas, land cover information, irrigation tank inventory and source-wise distribution of irrigated areas, together with conventional meteorological, canal flows and well inventory data. A semi-empirical water balance model was developed and validated using remote sensing derived objective information of the command area and the validated model used for predicting the groundwater table under normal rainfall conditions. Recharge and water balance in the study area indicated that the net recharge to the aquifer is negative to the tune of 2.54 Mm³ resulting in a fall of the groundwater table by 0.79 m during 1992-93. However, normalized groundwater recharge and water balance estimates indicate an impending waterlogging problem with an annual groundwater table rise of 0.35 m. In view of existing water management practices, a conjunctive water use plan of rotational operation of aquifers and canals is suggested.     

感潮闸控口门引排水量计算研究

针对上海市平原感潮河网地区闸控河流复杂的水流过程,为获得完整、准确、可靠的引排水量数据,通过对大治河东闸站和三甲港闸站现有监测分析获得的水位、水量、闸门运行工况等数据进行多元相关分析,得到引排水量与水位、引排时间、水闸过水断面面积的相关关系,并进行回归计算。回归计算结果与实测结果的误差分析结果表明：这种相关关系是比较可靠的,相对误差和标准偏差等均在可接受的范围内。说明用这种方法插补计算缺测期间的引排水量具有一定的可行性,可弥补因各种原因导致缺测带来的水量成果缺失的不足。该方法具有一定的普适性,可用于其他闸控河流水量计算分析,也可避免水位流量关系不显著、不稳定带来的困扰。     

航空发动机矢量推力测量系统的静态校准及不确定度评定方法研究

介绍了航空发动机矢量推力测量系统的静态校准原理,建立了静态校准的数学模型,并通过多元回归分析方法得到了各阶模型的校准系数.在此基础上,针对目前矢量推力测量系统缺少精度评定规范的问题,提出了一种基于校准系数误差传递的不确定度评定方法,并与传统的校准残余误差方法和验证残余误差方法进行了比较.校准实验结果表明,由于加载条件不...